LASIK Guider

Cataract Surgery Animation

noreply@blogger.com (LASIK Guider) — Wed, 22 May 2024 18:00:00 +0000

Refractive surgeries like LASIK and PRK usually aim to correct vision problems like nearsightedness, farsightedness, and astigmatism by reshaping the corne using excismer laser or by implanting artificial lens, called an intraocular lens (IOL).

Cataract surgery is performed to restore vision impaired by clouding of the eye's natural lens. During cataract surgery, the cloudy natural lens is removed and replaced with an artificial intraocular lens.

For some patients, particularly those with certain types of refractive errors, choosing a specific type of IOL can provide additional refractive benefits beyond just correcting the cataract. For example, if a patient also has significant nearsightedness or farsightedness, a multifocal IOL can potentially reduce their dependence on glasses for both distance and near vision. Similarly, toric IOLs can correct astigmatism, improving overall visual quality.

Though cataract surgery might be beneficial for refractive errors, it is not considered as a primary refractive procedure like LASIK or PRK. Any refractive benefits are secondary to the primary goals of cataract surgery, which are to remove the cataract and improve vision.

Cataract surgery is usually performed as an outpatient procedure under local anesthesia. Eye drops will be used to numb your eye, and you might also be given a light sedative to aid with relaxation. The clouded lens will be broken up by ultrasonic energy and suctioned out of the eye. The IOL is then implanted in its place.

Watch the video to learn how Cataract surgery is performed.

Can LASIK Fix Astigmatism?

noreply@blogger.com (LASIK Guider) — Fri, 26 Apr 2024 16:50:00 +0000

LASIK eye surgey is a popular laser vision correction procedure that correct refractive errors by reshaping the cornea, the transparent dome in front of the eye. LASIK surgery has changed the field of vision correction, offering patients the opportunity to achieve clearer vision and reduce their dependence on glasses or contacts.

For those with astigmatism , LASIK offers an effective treatment. To understand how LASIK can fix astigmatism, it is essential to first understand what astigmatism is and how it affects your vision.

What is astigmatism?

Astigmatism is a common refractive error caused by an irregularly shaped cornea or lens, which prevents light from focusing properly on the retina, the light-sensitive layer at the back of your eye. This results in blurred or distorted vision at all distances, making it difficult for individuals to see objects clearly. Astigmatism can range from mild to severe and can be present alone or in combination with other refractive errors as myopia or hyperopia.

Symptoms of astigmatism

Astigmatism can cause a variety of symptoms, which may vary in severity depending on the degree of astigmatism and other factors. Common symptoms include blurred or distorted vision at all distances, discomfort, headache, difficulty with Night Vision, redness of the eyelids margin and tearing. Persons with astigmatism may also try to improve vision by squinting, especially when trying to focus on distant objects.

Causes of astigmatism

Corneal Astigmatism: when the cornea is irregularly shaped.
Lenticular Astigmatism: when the lens is irregularly shaped.

Candidacy for LASIK with astigmatism

It is important to note that while LASIK is a highly effective treatment for astigmatism, not all patients may be suitable candidates for the procedure. Certain types of astigmatism, such as irregular astigmatism caused by corneal scarring or other eye conditions, may not be completely corrected with LASIK alone. Factors such as the severity of astigmatism, corneal thickness, and overall eye health may influence your eligibility for LASIK surgery. To be eligible for LASIK for astigmatism, you must meet certain requirements

You must be 18 years of age or older

Your vision must be stable

Your vision prescription must be within certain limits

Your eyes must be healthy

Your cornea must have sufficient thickness

You must be in good health

You must have realistic expectations

If you are not eligible to LASIK surgery for astigmatism, you may still be eligible for LASIK alternatives such as PRK (photorefractive keratectomy) for astigmatism or Implantable Collamer Lens (ICL). These LASIK alternative procedures can also effectively correct astigmatism and provide patients with clear vision.

How LASIK eye surgery works?

During LASIK surgery, a thin flap is created on the cornea using a handheld microkeratome blade in traditional LASIK or a femtosecond laser in All-laser LASIK. The flap is lifted and the underlying tissue is reshaped with the excimer laser to correct the refractive error. The flap is then replaced, and the cornea heals naturally, resulting in improved vision.

How LASIK can correct astigmatism?

LASIK works by reshaping the cornea to correct refractive errors. In the case of astigmatism, the cornea is irregularly shaped, causing light to focus unevenly on the retina, leading to blurred or distorted vision.

For astigmatism correction, corneal laser reshaping; is performed in a manner that addresses the irregular shape of the cornea, making it more spherical to properly focus light on the retina, resulting in clear vision.

Customized LASIK treatments , such as wavefront-guided LASIK or wavefront-optimized LASIK, can provide tailored corrections based on each patient's unique eye characteristics. Unlike traditional LASIK, which corrects nearsightedness, farsightedness, and astigmatism based solely on the patient's glasses prescription, customized LASIK takes into account the unique irregularities of the patient's cornea. This enables precise correction of astigmatism and other refractive errors with improved visual outcomes and fewer side effects.

How successful is LASIK for astigmatism

LASIK is safe and effective in correcting both low and high degrees of astigmatism with high success rates. The majority of patients experiencing significant improvement in their vision without the need for glasses or contact lenses. However, as with any surgical procedure, there are potential risks and side effects, so it's essential to discuss the benefits and potential complications with your eye surgeon before undergoing LASIK for astigmatism.

LASIK for astigmatism recovery

LASIK is known for its quick recovery time and minimal discomfort. The recovery time after LASIK for astigmatism can vary from person to person, but most patients experience significant improvement in their vision within the first few days after the procedure. Most Lasik patients can resume normal activities within a day or two after surgery. For the best results, it's important to follow your surgeon's instructions and attend all follow-up appointments for the best possible outcome.

If you are considering laser eye surgery for astigmatism , it is important to to know that your medical history, eyeglasses prescription, and other health factors are taken into consideration while determining your eligibility for laser eye surgery. You should consult your LASIK surgeon to discuss your specific needs and determine which vision correction procedure is right for you.

LASIK vs PRK which is better?

noreply@blogger.com (LASIK Guider) — Tue, 02 Apr 2024 23:56:00 +0000

PRK (Photorefractive keratectomy) and LASIK (Laser-assisted in situ keratomileusis) are popular laser-assisted corrective eye surgeries that correct refractive errors by reshaping the cornea, the transparent dome in front of the eye. They can treat common vision problems like

Shortsightedness (myopia): inability to see distant objects clearly
Farsightedness (hyperopia): inability to see close objects clearly
Astigmatism: irregular curvature of the eye that causes blurred distance and near vision.

Both LASIK and PRK are performed on both eyes during the same session as an outpatient procedure. Only topical anesthetic eye drops are used for numbing the surface of the eye during your surgery.

Eligibility for LASIK surgery and PRK surgery

To be eligible for a PRK or LASIK, you must meet certain requirements

You must be 18 years of age or older

Your vision must be stable

Your vision prescription must be within certain limits

Your eyes must be healthy

Your cornea must have sufficient thickness

You must be in good health

You must have realistic expectations

How LASIK laser surgery is performed?

LASIK involves creating a thin flap in the cornea using a handheld microkeratome blade in traditional LASIK or a femtosecond laser in All-laser LASIK. The flap is lifted, allowing the excimer laser to reshape the underlying corneal tissue. The flap is then folded back into place and heals naturally, which is why LASIK offers a much faster recovery time, typically within a few days.

How PRK laser surgery is performed?

Unlike LASIK, a PRK doesn’t involve cutting a flap in your cornea. Instead of a flap, the outermost layer of the cornea, called the epithelium, is removed with a femtosecond laser or a specialised brush. The excimer laser then reshapes the cornea. A bandage contact lens is placed over the eye to promote a new epithelial layer to grow back naturally. This healing process takes longer than LASIK, from one week to a month.

The main differences between LASIK and PRK

While both procedures have proven to be effective in improving vision, there are key differences between the two that you should be aware of when considering which option may be best for you.

	LASIK Eye Surgery	PRK Eye Surgery
Flap creation	Yes	No, epithelium is removed
Postoperative Symptoms discomfort, burning, light sensitivity and blurry vision	Minimal	More
Recovery time	Faster (within days)	Slower (within weeks)
Suitability	Not suitable for people with thin corneas	An option for people with thin or irregular corneas
Occupation and Lifestyle	Not suitable for people who participate in contact sports with a high risk of eye injuries	Better option for people who participate in contact sports with a high risk of eye injuries
Cost	Higher cost	Slightly cheaper

LASIK vs. PRK: Which Laser Eye Surgery Is Right for You?

If you are considering laser vision correction surgery, it is important to to know that your medical history, eyeglasses prescription, and other health factors are taken into consideration while determining your eligibility for laser eye surgery.

Both PRK and LASIK are safe and good options for correcting vision, but they have different advantages and considerations to keep in mind. People with thin corneas should not get LASIK because the flap created during the procedure may weaken the cornea even more. In this instance, PRK might be a better choice. If you have thinner corneas or irregular corneal surface, PRK may be a better option for you than LASIK since it causes less corneal tissue disruption.

Both LASIK and PRK have high success rates and can provide long-lasting results for patients who are good candidates for the surgeries. However, some studies have suggested that PRK may have a slightly higher risk of regression, meaning that some patients may experience a gradual worsening of their vision over time.

Because no flap is created in PRK, it is frequently advised for those who are more likely to experience an eye injury due to sports or specific occupations (athletes, pilots), as well as for those who participate in intense physical activity that could push the LASIK flap out of place.

LASIK is known for its quick recovery time and minimal discomfort, with patients often experiencing improved vision within hours of the surgery. Most Lasik patients can resume normal activities within a day or two after surgery. On the other hand, PRK typically has a longer recovery time compared to LASIK, with patients experiencing discomfort and blurry vision for several days following the procedure. This is because PRK involves removing the outer layer of the cornea, which takes longer to heal compared to the flap created in Lasik surgery.

While both procedures are generally safe and effective, there are some risks associated with each. Lasik patients may be at a slightly higher risk of developing dry eye syndrome or flap-related complications, while PRK patients may be at a higher risk of developing corneal haze or infection. It is important to discuss these risks with your eye surgeon and weigh the potential benefits and drawbacks of each procedure before making a decision.

Cost is another factor to consider when comparing LASIK and PRK. LASIK is typically more expensive than PRK, but many patients are willing to pay the extra cost for the quicker recovery time and reduced discomfort associated with the procedure.

Various factors such as your corneal thickness, preferred recovery period, occupation, lifestyle, and risk tolerance will determine which choice is ideal for you. It's important to consult with your eye surgeon to discuss your specific needs and determine which vision correction procedure is right for you.

LASIK Eye Surgery Video

noreply@blogger.com (LASIK Guider) — Sun, 11 Feb 2024 19:18:00 +0000

LASIK , or laser-assisted in situ keratomileusis, is a type of refractive surgery that uses a laser to reshape the cornea, the clear dome-shaped front surface of your eye, to improve your vision. LASIK is performed for correction of shortsightedness, farsightedness and astigmatism. It a painless surgical procedure typically performed on both eyes during the same session.

Here's how LASIK works:

Creating a flap: Your LASIK Surgeon uses a laser or a blade to create a thin flap in your cornea. This flap is folded back to expose the underlying tissue.
Remodeling the cornea: The excimer laser is used to remove tiny amounts of tissue from the underlying corneal stroma, which changes the shape of the cornea.
Replacing the flap: The corneal flap is then repositioned.

The entire LASIK procedure typically takes about 15 minutes and is performed on an outpatient basis.

Watch the video to learn how LASIK laser eye surgery is performed.

Photorefractive Keratectomy PRK Surgery

noreply@blogger.com (LASIK Guider) — Wed, 06 Dec 2023 21:33:00 +0000

What Is Photorefractive Keratectomy (PRK)?

Photorefractive Keratectomy is a type of laser eye surgery that is used to reduce dependence on eyeglasses or contact lenses by correcting vision in people with mild to moderate degrees of nearsightedness (myopia) or farsightedness (hyperopia), or astigmatism.

PRK was the first laser eye procedure developed in the late 1980s, approved by the FDA in 1995, and still in use today. Before LASIK eye surgey was invented, thousands of individuals had PRK treatment.

Is PRK eye surgery right for you?

If you are considering PRK, it is important to to know that your medical history, eyeglasses prescription, and other health factors are taken into consideration while determining your eligibility for laser eye surgery.

PRK is a good option for people who are not good candidates for LASIK. If you have thinner corneas or irregular corneal surface, PRK may be a better option for you than LASIK since it causes less corneal tissue disruption.

Because no flap is created in PRK, it is often recommended for people who are at higher risk of eye injury, such as from sports or certain jobs (Pilots, athletes) , and anyone who engages in a lot of physical activity that may move the LASIK flap out of place.

It's necessary to understand that PRK laser surgery cannot correct presbyopia. This is the typical age-related decline of near vision. Almost everyone who has good distant vision will require reading glasses beyond the age of forty.

To be eligible for a PRK, you must meet certain requirements

You must be 18 years of age or older

Your vision must be stable

Your vision prescription must be within certain limits

Your eyes must be healthy

Your cornea must have sufficient thickness

You must be in good health

You must have realistic expectations

Visiting your eye doctor for a comprehensive eye exam is the only way to determine your specific visual needs and whether PRK is the best surgery for you.

How PRK laser surgery is performed?

PRK surgery only takes about 10 to 15 minutes. It is performed while you are awake, but you will not feel any pain. It does not require the use of injections or needles.

PRK is performed on both eyes during the same session as an outpatient procedure. Only topical anesthetic eye drops are used for numbing the surface of the eye during your PRK surgery. This will reduce the desire to blink and eliminate any sensation of pain or discomfort that may cause eye movement during the procedure.

PRK laser eye surgery, like other types of refractive surgery, works by reshaping your cornea, the clear covering on the front of your eye, to allow light entering the eye to be correctly focused on the retina in the back of your eye.

Unlike LASIK, a PRK doesn’t involve cutting a flap in your cornea. There are two steps involved in PRK surgery:

The cornea's outermost layer, known as the epithelium, is removed with an alcohol solution or specialised brush. This is done to make the corneal stroma underneath accessible to the excimer laser.

Laser Ablation: Next, a tiny layer of corneal stroma tissue is removed using an excimer laser. The patient's refractive error determines how much tissue is removed.

In three to five days, the epithelium recovers on its own. In order to protect the cornea and to help it heal throughout this period, your surgeon will place a “bandage” contact lens over your eye.

You won’t be able or allowed to drive, so you’ll need someone to take you home.

PRK Surgery Recovery

It takes longer to recover from PRK than after LASIK. After your PRK procedure you will experience some discomfort, such as pain, burning, light sensitivity and blurry vision. Postoperative pain is greater than that of LASIK. But the discomfort normally goes away in a few days.

In two weeks, the majority of patients can see clearly enough to drive and carry out daily tasks again. However, it takes up to three months, and sometimes longer, for your vision to stabilize. PRK may take longer to achieve its full effect than LASIK. This is because it takes time for the cornea to be reshaped by the growing epithelium.

To ensure successful and rapid PRKrecovery process, it is essential to follow the instructions provided by your eye surgeon and properly use any prescribed medications or eye drops as directed. You should to avoid rubbing and touching your eyes until the eyes are healed.

To guarantee a successful PRK surgery, it is advisable to visit your eye doctor for a comprehensive eye exam. Your doctor will verify that you meet all the requirements and help you decide if PRK eye surgery is right for you.

How LASIK Surgery is Done?

noreply@blogger.com (LASIK Guider) — Wed, 12 Jul 2023 18:49:00 +0000

LASIK eye surgery is an outpatient refractive surgery procedure. It is performed under local anesthesia in a same-day surgery center or a surgeon's office. It is performed while you are awake, but sometimes your doctor may give you a mild sedative to make you relax.

LASIK is a painless surgical procedure typically performed on both eyes during the same session.

First, you will lie down in a bed, which is adjusted to exactly line up the eye to be treated with the laser. One of your eyes is covered to reduce distraction.

Next, the medical staff clean your eye with a cotton swab. Then they put anaesthetic drops in your eye. These drops keep you from feeling pain during the LASIK procedure and help keep you from blinking. You may be given other medicine as well.

After your eye has been cleaned and medicated. Your LASIK surgeon places a metal device in your eye called the speculum. The speculum keeps your eye open during surgery. This might feel a little uncomfortable, that's normal.

You will be asked to look at a blinking red light. This helps make sure your eye remains in the correct position during LASIK surgery. Next, the doctor makes three or four ink marks in your eye. These marks show the doctor exactly where to put the flap. When the procedure is done, you will not feel the ink marks being applied.

Then your LASIK doctor places a small metal plate on your eye called a suction ring. The suction ring helps to hold your eyes still during surgery. After the suction ring is in place, it is pushed down onto the cornea. This will not hurt but it may feel like a vacuum has been placed on your eye.

Your vision may go black for a few moments. These sensations are normal. The doctor then starts the LASIK flap creation process. First, He puts a cutting tool on top of the suction ring. The cutting tool is called a microkeratome.

Next, the doctor uses the cutting tool to make a small incision in the top of the cornea. You may feel a slight tugging sensation on your eye. The doctor then returns the cutting tool to its original position. This leaves a flap of tissue on the top of the cornea.

The doctor pulls the flap back with a thin metal rod. You will still be able to see but your vision may become hazy. The Excimer laser is then projected into your eye for a few moments. You won't see the laser, but you may hear a loud clicking and notice a burning smell. The laser stops when the cornea is in the right shape.

The doctor may add eye drops and clean the exposed area. The flap is then put back into its original place using a small metal rod. The doctor makes sure it is in the right place by lining up the ink marks, more drops are placed in your eye to make sure it heals well, the speculum holding your eye open is removed and you will be asked to blink a few times.

Watch the video to learn how LASIK laser eye surgery is performed.

Dry Eye Symptoms and Signs

noreply@blogger.com (LASIK Guider) — Fri, 16 Jun 2023 15:54:00 +0000

Dry eye disease is a frequent disease in which your tears are unable to adequately lubricate your eyes. Tears can be insufficient and unstable for a variety of causes.

Dry eyes, for example, can occur if you don't produce enough tears or if your tears are of low quality. This tear instability causes inflammation and damage to the surface of the eye.

Dry eyes can occur in a variety of scenarios, including flying, being in an air-conditioned room, riding a bike, or staring at a computer screen for several hours and after LASIK eye surgery.

Watch the video to know signs and symptoms of dry eye, which usually affect both eyes

Are You Awake During LASIK Surgery?

noreply@blogger.com (LASIK Guider) — Mon, 08 May 2023 18:47:00 +0000

LASIK is a widely used laser eye surgery that can correct vision in people who are nearsighted or farsighted, or who have astigmatism. It is done to improve vision and reduce your dependence on eyeglasses or contact lenses.

The LASIK procedure, like other types of refractive surgery, works by reshaping your cornea, the clear covering on the front of your eye, to allow light entering the eye to be correctly focused on the retina in the back of your eye.

LASIK is a painless surgical procedure typically performed on both eyes during the same session. It is generally performed as an outpatient procedure under topical anaesthesia.

The LASIK procedure is done while you are awake, but you will not feel any pain. It does not require the use of injections or needles.

Only topical anesthetic eye drops are used for numbing the surface of the eye during your lasik surgery. This will reduce the desire to blink and eliminate any sensation of pain or discomfort that may cause eye movement during the procedure.

If you feel anxious about being awake during the LASIK procedure, your LASIK surgeon will give you a mild sedative or other medication before the surgery to help you relax. The use of a mild sedative is common with LASIK.

Why You Have To Be Awake During LASIK Surgery?

General anesthesia, used for major surgeries, causes loss of consciousness or puts you to sleep and makes you unable to move. The use of general anesthesia requires the presence of a specialized medical professional known as an anesthesiologist, who is responsible for administering the anesthesia.

Unlike most surgeries that require general anesthesia, undergoing LASIK eye surgery does not require the use of general anesthesia to induce sleep, and it is actually mandatory to be alert and awake during the procedure. There are many reasons why you stay awake during laser eye surgery:

The LASIK procedure is a quick surgical procedure as it only takes around 15 minutes in the laser room to complete the treatment for both eyes. In fact, the LASIK procedure per eye merely lasts one to two minutes and the process of reshaping the cornea by excimer laser takes just a few seconds.

Your LASIK surgeon needs your cooperation during the procedure so that he can do the procedure as accurately as possible. You will be asked to look at a point of light that is not a laser but a type of light guide. Staring at at the light helps you to keep your eye still, while the excimer laser reshape your cornea.

Topical anesthesia avoids the risks that come with general anesthesia. You can go home the same day because you won't need to recover from the anaesthetic medicines.

LASIK surgery cost would be more if the patient was put to sleep with general anesthesia, but it wouldn't make the procedure better in any important way.

To ensure successful and rapid LASIK recovery process, it is essential to remain alert after your surgery to follow the post lasik instructions provided by your eye surgeon and properly use any prescribed medications or eye drops as directed. You should to avoid rubbing and touching your eyes until the eyes are healed.

If you are worried about being awake during lasik surgery, it is important to keep in mind that patients who have undergone LASIK say it was actually easier and faster than they thought. So don't worry too much!

To guarantee a successful LASIK surgery, it is advisable to seek advice from your eye doctor before undergoing LASIK. This will assist you in obtaining all the necessary directions and responses to whatever queries you may have.

Who Is a Good Candidate for LASIK Surgery?

noreply@blogger.com (LASIK Guider) — Tue, 02 May 2023 17:30:00 +0000

Because LASIK eye surgery has become the most frequently performed procedure to treat myopia, hyperopia, and astigmatism in recent years, many people think that laser eye surgery is a good option for everyone.

In reality, not every person is a good candidate for LASIK vision correction surgery. However, you should be aware that there are alternate methods for correcting refractive problems. These procedures can help you see clearly without the need for glasses or contact lenses if you are not a candidate for LASIK.

Several conditions can hurt your chances of LASIK eligibility. In general, the best possible results are obtained when Laser vision correction procedures are performed on a healthy person with healthy eyes.

Your eligibility for LASIK is determined on an individual basis by taking into account your medical history, prescription, and other health factors. The only method for determining your unique visual requirements and whether LASIK is the right procedure for you is to visit your eye doctor for a thorough eye exam.

However, before going to your LASIK eye surgery consultation, I will give you an overview about general requirements that can guide you in deciding if LASIK is the right procedure for you.

You must be 18 years of age or older

Most Lasik surgeons agree that 18 is the minimal age for laser vision correction surgery because it is the age at which your eyes are fully developed. Although LASIK has been successfully used to treat vision errors in adults, the FDA has not approved the treatment for anyone under the age of 18.

As an exception, patients younger than these ages who have significant anisometropia may be treated with LASIK regardless of the minimal age criteria.

Your vision must be stable

Even if you are over the age of 18, your prescription may still be changing. Having a stable prescription is essential if you want your LASIK surgery to be as effective as possible. Most lasik surgeons recommend that you have a stable vision prescription for at least 12 months before performing LASIK.

Changes to your corrective eyewear prescription may indicate that your corneas are changing and that the results of LASIK surgery could be short lived.

Your vision prescription must be within certain limits

Although your eyeglasses prescription is just one of several factors your lasik surgeon considers before recommending laser vision correction, checking your eye prescription is a good idea to find out if you if LASIK is right for you.

Your eye prescription should fall within certain limits. During your lasik consultation your Lasik surgeon will assess the degree of nearsightedness, farsightedness, and/or astigmatism you have and determine whether your eye prescription is within the recommended treatment range for LASIK vision correction surgery.

Other vision correction procedures, such as phakic IOL implants or refractive lens exchange, may be suitable options if your prescription is too high for LASIK.

Your eyes must be healthy

In order to be candidate for LASIK vision correction surgery, your eyes must be in good health and free of any corneal diseases such as keratoconus (a progressive thinning and bulging of the cornea) or external eye problems.

Certain eye problems like infections, conjunctivitis (pink eye) and chronic dry eye must be treated before LASIK can be performed.

Specific eye diseases and conditions, including; severe cataracts, uncontrolled glaucoma and certain retinal and optic nerve diseases can break your eligibility for LASIK or other laser vision correction procedures like PRK.

Your cornea must have sufficient thickness

LASIK surgery improves your vision by making a flap in the cornea. After the flap’s creation, an excimer laser reshapes the cornea. You should be aware that you need to have enough corneal thickness to correct your eyesight by LASIK. The amount depends on how much refractive error you have.

Your LASIK surgeon will make sure that a minimum quantity of corneal tissue will be left unaffected by the LASIK treatment after the flap is made and the excimer laser is used. With Femto LASIK, the surgeon may be able to safely correct greater amounts of refractive error by using a thinner corneal flap.

If your corneas are too thin, you cannot safely have the LASIK procedure, then other LASIK alternatives such as PRK, phakic IOL implants or refractive lens exchange might be a better option for you.

You must be in good health

Even though LASIK is a quick and easy surgical procedure, it is still a surgery. You should be generally in good general health, this facilitates effective LASIK recovery.

If you have any uncontrolled degenerative conditions or uncontrolled autoimmune diseases such as rheumatoid arthritis or systemic lupus may put you at risk for corneal complications, infection and irregular healing. LASIK may be performed in diabetic patients with well-controlled glycemic levels and no systemic or ocular complications.

Your eye doctor will guide you through your lasik consultation and let you know if any pre-existing medical conditions will prevent you from having LASIK. You should tell your surgeon about all the medications you are taking or have taken within the past year.

You must have realistic expectations

Although LASIK will almost certainly improve your vision and reduce your dependence on glasses and contact lenses, you might still need glasses for some activities, like driving at night.

It is important to know that LASIK does not prevent or completely correct presbyopia, which commonly starts to appear around age 40. After surgery, this patient might still require reading glasses.

Your final satisfaction with your LASIK procedure outcome depends mostly on having realistic expectations, so before making your decision to have LASIK, you should be fully aware of the possible advantages, disadvantages, outcomes, risks and potential LASIK complications.

Is LASIK an Option for Children and Teens?

noreply@blogger.com (LASIK Guider) — Wed, 12 Apr 2023 16:20:00 +0000

For millions of teens who suffer from refractive errors, seeing clearly without glasses or contacts is a dream. As the popularity of LASIK is increasing everyday, no surprise that many teenagers are eager to know if LASIK is an option for them. On the parent’s side, many of them question if LASIK eye surgery would be effective on their children as in adults. They hope that LASIK would help their children see better in school and enable them to contribute in recreational and sporting activities, which can enhance their social development.

Why LASIK is not an Option for Children and Teens?

While LASIK has been used to correct nearsightedness, farsightedness and astigmatism in adults with good efficacy and visual results, the U.S. Food and Drug Administration (FDA) has not approved the procedure for persons under the age of 18.

Normally, the human eye continues to grow during childhood with significant change in shape and size. As a result, vision only stabilizes, when the eye completes it development around the age of 20 years.

For this reason, LASIK eye surgery results in teens may be temporary or unpredictable in contrast to the permanent results in adults. As a result, the LASIK procedure would probably have to be repeated when the teenager reaches early adulthood.

When LASIK would be an Option for Children and Teens?

In current practice, most ophthalmologists will not perform LASIK on a young person until at least the age of 20. However, in very rare circumstances, the minimum age requirements for LASIK may be ignored to treat children or teens who suffer from severe vision conditions such as anisometropic amblyopia “lazy eye”.

Treatment of those children with LASIK would be an off-label use of the medical device and would be only considered when:

Standard treatment measures like glasses, contacts and patching have failed to improve vision.
Chronic noncompliance with, or intolerance of, standard treatment threatens normal visual development.

13 Instructions You Should Follow after LASIK

noreply@blogger.com (LASIK Guider) — Tue, 11 Apr 2023 15:39:00 +0000

Because what occurs after your LASIK surgery can affect your vision just as much as the procedure itself, it is very important to know what you should expect after LASIK. What you should do after LASIK? And what you should avoid after LASIK?

After your LASIK procedure, your surgeon will give you oral and written instructions about the early post-LASIK period. To have a better outcome after your LASIK surgery, you should follow your doctor’s instructions.

Let’s now highlight the general instructions you should follow after your LASIK surgery and explain their importance.

1. Rest or Sleep for Few Hours after LASIK

The best thing to do immediately after LASIK is to go home and rest as much as possible for the remainder of the day. Try to sleep the first few hours because keeping your eyes closed speed your recovery and help reduce discomfort. If you can’t sleep, rest with your eyes closed as much as possible for the first few hours.

2. Use Your Prescribed Medications

After LASIK surgery, start using your eye drops as directed by your doctor. These eye drops usually include:

Combined antibiotics-steroids eye drops to prevent infection and control inflammation.
Preservative free artificial tears eye drops to lubricate the LASIK flap and reduce irritation. Frequent use of artificial tears eye drops is recommended for the first 3 months after LASIK, because the tears secretion after LASIK surgery.

To decrease the risk of LASIK complications such as infection and displaced flap, don’t forget to follow your doctor’s instructions on how to properly instill eye drops after LASIK.

3. Avoid touching or Rubbing Your Eyes for 2 Weeks after LASIK

Since the LASIK flap is not sutured, if you rub or touch your eyes, the LASIK flap may become dislodged, requiring repositioning and further treatment. In addition, touching your eyes can transmit contaminants to your eyes, increasing the risk of infection.

4. Wear a Protective Eye Shield while Sleeping

To prevent accidentally rubbing or poking your eyes while sleeping, wear a protective shield over your eyes for the first three nights after your LASIK procedure. These eye shields come in various designs and are usually given to you by your doctor.

5. Wear Dark Glasses After LASIK When You Go out

To help your cornea heal and protect your eyes from exposure to bright light which may irritate your eyes, wear dark sunglasses during day after your LASIK surgery.

6. Take a Couple of Days Off Work after LASIK

You may be able to return to work the day following your LASIK procedure, but if possible, take a couple of days off work until the post-LASIK symptoms get better.

7. Resume Your Usual Daily Activities Gradually After LASIK

When you can resume a certain activity after LASIK surgery will depend on the amount of activity required, how you feel, and your doctor's instructions. One day after your LASIK surgery, you can read, watch TV and work on the computer in moderation. It is important to keep your eyes moisturized with artificial tears eye drops during these activities.

Two to three days after your LASIK procedure, you can resume Non-contact sports such as running, golf, etc., if you feel capable. Wear a headband to keep sweat out of your eyes. Strenuous or contact sports such as boxing, football, karate, etc. should not be attempted for at least one month after your LASIK surgery. However in the first few weeks after your LASIK procedure, if there is any risk that you might take a direct blow to the eye (e.g., racquet sports), you should wear protective eyewear (e.g., protective goggles).

8. Avoid Driving for 2 Days after LASIK

Your surgeon will warn you not to drive for a certain period after your LASIK procedure. This period can vary depending on how your eyes are healing. Most LASIK patients are allowed to drive 2-3 days after the procedure, but only for short periods of time.

9. Avoid Eye Make-up for One Week after LASIK

You may wear face make-up after 3 days, but avoid wearing eye make-up and applying lotions or creams around the eye for at least one week after your LASIK procedure. This rule is important to:

Reduce the possibility that makeup particles might get under the LASIK flap
Reduce the possibility of accidentally injuring the flap with a make-up applicator
Reduce the possibility of infection from contaminated make-up

It is strongly recommend that you buy new eye make-up, particularly mascara, eye liner and eye shadow, to avoid possible infection after your LASIK treatment.

10. Avoid Swimming for 2 Weeks after LASIK

To reduce the risk of infection from contaminated water, you should stay out of swimming pools for at least 2 weeks following your LASIK procedure, and rivers, lakes, hot tubs, sea and oceans for one month after your LASIK treatment.

11. Take Baths instead of Showers for 2 Weeks after LASIK

You may take showers and baths after your LASIK procedure, but try to keep your eyes closed to prevent the water, soap or shampoo from getting in your eyes. Be careful not to allow the water to strike your face directly for at least one week after your LASIK surgery. When drying off, use a face cloth and avoid rubbing your eyes.

12. Keep up All Your Post-LASIK Appointments

Follow up after LASIK surgery is as important as the actual procedure. Your doctor should examine your eyes the day following your LASIK procedure. This is important to make sure that the flap has remained in proper position and no evidence of infection or inflammation is present.

In the absence of complications, your next appointments are usually 1 week, 1 month, 3 months, 6 months, and 1 year after LASIK surgery. Keeping your follow up appointments are critical to assess the healing of your eyes and the stability of your vision.

13. Contact Your Doctor Immediately if You Suspect a Problem

After your LASIK procedure, you should expect some common symptoms such as burning and tearing, foreign body sensation, sensitivity to light, and discomfort. These symptoms should get better within 2-3 days after LASIK surgery. If your symptoms get worse or if you suspect a problem, you should contact your surgeon immediately and not wait for your scheduled visit.

The Structure & Function of the Eye

noreply@blogger.com (LASIK Guider) — Tue, 11 Apr 2023 14:17:00 +0000

In order to understand how LASIK eye surgery is performed, you need to have an idea about the basic structure and function of your eyes. Only a basic overview of the anatomy and physiology of the visual system will be discussed.

The Structure of the Human Eye

Before discussing the structure of the eye, give yourself a minute to look at your eyes in a mirror.

Try to notice its structure and position in your face.

Have you ever wondered about the structure of your eyes? or How this miraculous organ works?

Now it is time to learn more about your eyes. Let’s take a tour in the eye, starting from the outside and work our way toward the back of the eye.

The Eyelids

The Eyelids are mostly composed of skin, muscles for movement and glands for secretion of oil into the tears to keep the tears from evaporating too quickly. The eyelids protect the eye from strong light, dust and foreign objects. Closure of the lids during sleep protects the surface of the eye from drying. Blinking the eyelids lubricate the eye.

The Palpebral Fissure

The Palpebral Fissure is the space between the upper and lower eyelids.

The Eyebrows

The Eyebrows help to protect the eyes from dust and direct sun light. In addition, they prevent sweat from dripping in the eyes.

The Eyelashes

The Eyelashes are short hairs arising from the eyelids margin and help protect the eye from sun light and dust. The eyelashes are more numerous in the upper lid than the lower.

The Conjunctiva

The Conjunctiva is a transparent thin membrane that covers the front of the eyeball and lines the inside of the eyelids. The conjunctiva is loose enough to allow the eye to move freely. It contains cells that liberate mucus into the tears, helping the tears to spreads evenly over the front surface of the eye.

The Tears and The Tear Film

The Tears are produced by the lacrimal glands. The tears flow down the front of the eye and drain through small pores on the eyelids margin. Then tears flow down the lacrimal tubing and finally drain into the nose. The tears wash the eyes and carry foreign objects to the side of the eye.

The Cornea

The Cornea is the clear crystal part of the front surface of the eye. In addition to protecting the delicate structures inside the eye, the cornea helps focus rays of light on the retina to create an image. Its working is similar to that of the lens of a camera, focusing rays of light to create an image on the film. As the cornea is the target part of the eye in LASIK eye surgery, we need to discuss a little more details about its structure and function: Further details about the cornea.

The Sclera

The Sclera, the white of the eye, is the outer fibrous protective coat of the eye. It helps maintain the shape of the eye and receives attachments from the muscles, which move the eye.

The Iris

The Iris is colored part of the eye which lies behind the cornea and inside the eye. It is composed of muscles and contains pigments. The iris has a hole in its center called the pupil. The iris can change the size of the pupil, by its muscles, to control the amount of light entering the eye.

The Lens

The Lens is the flexible, transparent structure found behind the iris. It is held in place by ligaments called zonules. In order to see clearly objects at different distances, the lens has the ability to change its shape to focus images on the retina. This process is known as accommodation.

The Eyeball

The Eyeball is nearly a sphere in shape with a diameter of around 24 mm (about one inch).The eye wall is made of three coats:

Outer coat is fibrous, and is formed of the cornea and the sclera. Being tough and strong, this layer serves to maintain the shape of the eye and to protect the underlying delicate coats.
Middle coat (uvea) contains blood vessels and pigments and divided into the iris, ciliary body, and the choroid, all are continuous with each and are together named the uvea. The function of this layer is to provide nutrition to the other coats.
Inner coat (retina) is the sensory part of the eye and is formed of nervous tissue. The role of the retina is to sense light and transform it into electrochemical signals that the brain interprets as vision.

The cavity of the eyeball is divided into three chambers:

The anterior (front) chamber is the space between the cornea and the iris (the colored tissue at the front of the eye).
The posterior (back) chamber is the space between the iris and the lens
The vitreous chamber is the space between the lens and the retina.

Both the anterior and posterior chambers are filled with a clear fluid called the aqueous humor, which maintain the pressure inside the eye. The vitreous chamber is filled by a viscous, clear jelly (vitreous humor), which support and protect the lens and the retina.

The Optic Nerve

The Optic Nerve is a bundle of nerve fibers, which transmits the visual information from the retina to the brain.

The Orbit

The Orbit is a pear shaped cavity in the scull; representing the bony housing of the eye. It provides the protection for the eye, mainly from trauma.

The Eye Muscles

The Eye Muscles: there are six muscles around each eyeball, working together to move the eye in all directions. These muscles are called the extra-ocular muscles and are attached to the bones of the orbit and to the surface of the sclera.

How The Eye Works? (Mechanism of Vision)

Vision is a dual task performed by the eye and the brain. Our Eyes are the organs that detect light and form an image of objects on the retina. The image is transmitted along the optic nerve in the form of electrochemical signals to the visual and other specialized areas of the brain, where interpretation of what is seen takes place.

The full series of LASIK Vision Correction Explained tutorials are

Tutorial 1: The Structure and Function of the Eye
Tutorial 2: Refraction and Refractive Errors
Tutorial 3: Myopia – Near- Sighted Eye
Tutorial 4: Hyperopia – Farsighted eye
Tutorial 5: Astigmatism
Tutorial 6: Presbyopia
Tutorial 7: Eyeglasses - Spectacles
Tutorial 8: How to Read Glasses Prescription
Tutorial 9 : Contact Lenses - Contacts
Tutorial 10: What is Refractive Surgery?
Tutorial 11: What is LASIK?
Tutorial 12: How is LASIK performed?

LASIK Vision Correction Explained

noreply@blogger.com (LASIK Guider) — Sun, 09 Apr 2023 23:44:00 +0000

LASIK eye surgery is the most commonly performed laser vision correction procedure nowadays to decrease or eliminate your dependence on glasses or contact lenses. The procedure duration is about 10 minutes with short recovery time and instant results.

This tutorial is a complete guide about LASIK vision correction surgery to give you an overview if lasik vision surgery is an option for you. It is easy to understand, especially to those who have no medical knowledge. The tutorial is divided into a number of sub-tutorials that explain related information about LASIK in detail. The best way to understand LASIK vision correction Surgery in details is by going through the sub-tutorial sequence one by one.

The earlier sub-tutorials are focused on explaining the basic structure and function of the eye, refraction and refractive errors, as a general introduction to LASIK vision correction. The later sub-tutorial explain LASIK eye surgery in more detail and help you understand what you should do before LASIK, what will happen during the LASIK surgery, and what you should expect after LASIK surgery.

LASIK Vision Correction Surgery Explained

Tutorial 1: The Structure and Function of the Eye
Tutorial 2: Refraction and Refractive Errors
Tutorial 3: Myopia – Near- Sighted Eye
Tutorial 4: Hyperopia – Farsighted eye
Tutorial 5: Astigmatism
Tutorial 6: Presbyopia
Tutorial 7: Eyeglasses - Spectacles
Tutorial 8: How to Read Glasses Prescription
Tutorial 9 : Contact Lenses - Contacts
Tutorial 10: What is Refractive Surgery?
Tutorial 11: What is LASIK?
Tutorial 12: How is LASIK performed?

Refraction and Refractive Errors

noreply@blogger.com (LASIK Guider) — Sun, 09 Apr 2023 14:42:00 +0000

Refraction, in physics, is the bending of light rays when they pass from one medium to another. The degree of bending of light rays will be variable, depending on the density of the two media. Air for example has a low density, so it causes slight bending of light. In contrast, glass has a higher density, so it causes larger bending of light.

When applying this principle in practice, we can say that a lens or a curved mirror has a light-refractive power (light- bending power), the larger the refractive power, the stronger the lens.

The unit of measurement of refractive power is the diopter (D) and hence it can be called dioptric power. The diopter is defined as the power of a lens that brings parallel light rays falling on it to a focus at a distance of one meter.

For example, a 4-diopter lens brings parallel rays of light to focus at 25 cm (1/4 meter). If the lens is concave its power is expressed as minus and if it is convex its power is expressed with a plus sign.

The Eye as an Optical System:

The eye is a complex system of lenses. The main refractive structures in our eyes are the cornea and the lens, working together to focus the parallel light rays of light on the retina at the back of the eye. The refractive power of the cornea is about + 42 D where that of the crystalline lens within the eye is about + 18 D.

As the cornea has a larger refractive power, it is more important for focusing light rays on the retina at the back of the eye. However, refraction alone is not enough to obtain a clear image, especially, when we are looking at near objects. From here, the importance of the lens arise, as it can vary its refractive power by changing shape from being spherical to be more oval and back again when needed, in a process known as accommodation (the ability of the eye to change its refractive power in order to see clearly objects at different distances).

When the light rays perfectly focus on the retina at the back of the eye, the individual does not need to wear spectacles and is said to be emmetrope. However, the shape of the cornea and the eye are not usually ideal and so the image does not focus exactly on the retina (blurred). These imperfections in the focusing power of the eye are called refractive errors (defects). The individual who have a refractive error is said to be ammetrope.

Emmetropia versus Ammetropia

From the previous discussion we can define Emmetropia as the normal refractive condition of the eye in which with accommodation completely relaxed, parallel light rays from an object come to focus exactly on the retina, creating a sharp image of that object.

On the other hand Ammetropia can be defined as a condition of refraction in which with accommodation, completely relaxed, parallel light rays from an object do not come to focus exactly on the retina, creating a blurred image of the object.

Causes and Types of Refractive Errors:

Both genetic and environmental factors appear to play a role in the development of refractive errors. Trauma or ocular disorders may induce refractive errors. Refractive errors include:

Myopia (also called near- or short-sightedness)
Hyperopia (also known as farsightedness, long-sightedness or hyperopia)
Astigmatism
Presbyopia
Aphakia means the absence of the lens from the eye, which can occur as a congenital disorder or commonly after cataract operations.
Anisometropia is a significant difference between the refractive errors of the two eyes (usually > 3 diopters).

Diagnosis and Treatment of Refractive Errors:

Combinations of myopia and astigmatism or hyperopia and astigmatism are common. The diagnosis of refractive errors is often performed by ophthalmologists or optometrists combined with a comprehensive medical eye evaluation.

The primary reason for treating refractive errors is to improve a patient’s visual acuity and visual comfort. Occasionally, a very small refractive error in one patient may require correction, while another individual may function well without problems with an uncorrected refractive error. Patients with high refractive errors, generally require correction to reach adequate vision. Other reasons for correction of refractive errors include enhancing binocular vision (e.g., for driver safety) and decreasing squint, (cross-eyed).

Eye Glasses are the simplest and safest means of correcting a refractive error. A contact lens can correct a wide range of refractive errors by replacing the cornea as the primary refractive surface of the eye.

Persons who do not wish to wear glasses most frequently use contact lenses. Some patients such as persons who have high refractive errors, an irregular corneal surface or shape, only reach optimal visual function with contact lenses.

Surgical procedures aimed at improving the focusing power of the eye are called Refractive Surgery procedures (e.g., LASIK).

LASIK for Correction of Refractive Errors

In LASIK eye surgery, precise and controlled removal of corneal tissue by a special laser reshapes the cornea changing its focusing power. LASIK vision correction is effective in treatment of low and moderate myopia with or without astigmatism, as well as hyperopia with or without astigmatism. Other types of refractive surgeries such as implantable lenses (Visian ICL and Verisyse) can correct higher levels of myopia.

The full series of LASIK Vision Correction Explained tutorials are Tutorial 1, Tutorial 2, Tutorial 3, Tutorial 4, Tutorial 5, Tutorial 6,Tutorial 7, Tutorial 8, Tutorial 9, Tutorial 10, Tutorial 11 and Tutorial 12.

Pain or Discomfort after LASIK Eye Surgery

noreply@blogger.com (LASIK Guider) — Fri, 07 Apr 2023 19:20:00 +0000

LASIK eye surgery is considered to be such a painless procedure when compared to surface procedures such as photorefractive keratectomy (PRK).

After uncomplicated LASIK, the majority of patients have minimal to no pain, burning and tearing for the first 2 -3 hours, slight foreign body sensation, light sensitivity, and discomfort. These symptoms are more common after LASIK enhancements that require flap lifting, as compared to primary LASIK treatments.

Despite the high efficacy, safety, and fast epithelial healing in LASIK, some patients still complain of disabling pain during the early period (24-48 hours) after LASIK. Rarely, the pain can also result in involuntary spasm of the eyelids which may cause flap dislodgment.

Causes of Pain or Discomfort after LASIK (24-48 hours)

It is possible that anxiety may play a role in lowering the pain threshold. Irritation of the eyelid structures and the eye surface due to the pressure exerted by the speculum (eyelid holder) and suction ring may be the source of both eyes pain and orbital discomfort experienced by the patients during and after LASIK surgery.

You should know that it is normal to feel pressure from the speculum and suction ring as the eyelid structures cannot be adequately anesthetized during the procedure with topical anesthetics.

Management of Pain or Discomfort after LASIK

You should expect mild discomfort that should resolve within a few to several hours. Also you should know that the two eyes may have different amount of discomfort.

If you experienced severe pain associated with generous tearing, you must contact your doctor immediately. Severe or persistent pain after LASIK may indicates flap dislocation, significant epithelial disruption, or even total loss of the flap.

Your doctor will examine your eyes at the slit-lamp to ensure that the flap is intact and determine the cause of pain. The Management will vary depending on the underlying cause.

In general, generous use of artificial tears eye drops is helpful. Narcotic analgesics are not necessary after LASIK eye surgery, though sedatives or Non-Narcotic pain medications may be recommended by your doctor if you cannot tolerate the pain.

Common Symptoms after LASIK Eye Surgery

noreply@blogger.com (LASIK Guider) — Thu, 06 Apr 2023 16:00:00 +0000

As each person is different, the symptoms after LASIK eye surgery can be different for each patient. However, immediately after uncomplicated LASIK procedure, you should expect some very common temporary symptoms that should resolve within a few days either spontaneously or by the use of medications for some time.

Discomfort or Pain after LASIK

Immediately after your LASIK procedure, your eye may burn, itch, or feel like there is something in it for a couple of days. You may experience some discomfort, or in some cases, mild pain. Your doctor may suggest you take a mild pain reliever.

You will instinctively want to rub your eye, but do not. If you rub or bump the eye, the LASIK flap may become dislodged, requiring repositioning and further treatment.

Blurry or Hazy vision after LASIK

Most patients achieve good vision the day of LASIK eye surgery. However, right after the procedure, you should expect your vision to be blurry or hazy for a day or two, do not worry; this is a normal part of the healing process and your vision will gradually clear.

Why your vision is blurry right after LASIK?

The eye drops used before or during LASIK surgery cause some blurring. In addition, there is extra water within your cornea after the LASIK treatment, this make you see as if you are looking behind water. In about 4-5 hours, the vision will be clearer.

Why your vision fluctuates after LASIK?

Your eyes need time to heal after LASIK and this time is variable between patients. While your eyes are healing, it is normal for your vision to go back and forth between clear and blurry phases for several weeks. However, vision will continue to improve, and best possible vision can still take two to three months to occur, especially with higher degrees of refractive errors.

Subconjunctival hemorrhage (blood) after LASIK

The conjunctiva contains many small, fragile blood vessels that are easily ruptured or broken. When this happens, blood leaks into the space between the conjunctiva and sclera (white of the eye). Occasionally, those blood vessels may rupture during LASIK eye surgery, resulting in bleeding under the conjunctiva.

Do not worry; this is a harmless and self-limited side effect of LASIK surgery. Like a bruise on the skin, a subconjunctival hemorrhage spontaneously resolves with time. It may take a couple of weeks to resolve completely.

Light Sensitivity, Glare, Starbursts or Haloes around Lights

Just after LASIK, you may feel your eyes irritated when exposed to bright lights indoors or outdoors. Your surgeon will usually recommend that you wear an eye shield for the first few hours after surgery to help your cornea heal and to protect the eye from bright lighting. In addition, some patients observe a glare, starbursts or haloes around lights after LASIK surgery. In most cases, theses symptoms will fade away over time. However, in some cases, a LASIK enhancement (a second LASIK procedure) may be required to correct this problem.

Finally, it is very important after LASIK eye surgery that you follow the instructions your doctor has given you. Symptoms mentioned above should improve two or three days after LASIK eye surgery. If your symptoms get worse or if you have severe pain, you should contact your doctor immediately.

What is the Normal Corneal Thickness?

The thickness of the cornea normally varies between people with an average of about 550 microns (that’s about 1/2 millimeter) in Caucasians. It is less in Blacks (520 microns) and even less in Asians.

How Corneal Thickness is measured?

Corneal thickness is measured with a device known as a pachymeter. The most common method of pachymetry is ultrasound, but certain corneal imaging systems such as Orbscan and Pentacam can also be used. The latter systems can provide a map representing the relative thickness of your cornea at various locations.

What is the Ideal Corneal Thickness for LASIK?

There is no ideal corneal thickness for LASIK. However, you should know that to improve your vision by LASIK surgery, you should have an adequate amount of corneal thickness. This amount depends on the degree of your refractive error.

Why Corneal Thickness is measured before LASIK Surgery?

It is important to determine your corneal thickness before your LASIK procedure because LASIK improves your vision by reshaping your cornea and it reshapes it by removing some tissue from your cornea. If the cornea is made too thin, vision may fluctuate and be of poor quality.

What is the Ablation Depth?

Ablation depth is the amount of tissue removed by the excimer laser from the middle layer of the cornea called the stroma. If you are shortsighted, the removal is in the center of your cornea. If you are farsighted, the removal is at the periphery of your cornea.

How Ablation Depth is calculated?

Ablation depth depends on the amount of treatment required, which in turn depends on the degree of your refractive error. Pupil size and parameters of the chosen excimer laser are other factors that affect the Ablation Depth.

In general, we can assume that with a pupil size of 6.0 mm, the excimer laser removes 12 microns of tissue for each diopter of LASIK treatment.

For example, if you have 4 diopters of shortsightedness, the ablation depth required to correct you vision would be 4 x 12 = 48 microns.

What is the Residual Stromal Bed?

Your LASIK surgeon will ensure that after creating the flap and applying the excimer laser, there is a minimum amount of corneal tissue remains untouched by the LASIK procedure. This critical amount is called the Residual Stromal bed and it is important to preserve the strength and integrity of your cornea after the LASIK procedure and avoid serious LASIK complications such as corneal ectasia.

How thick the Residual Stromal bed should be?

When the U.S. Food and Drug Administration (FDA) approved LASIK, it recommended that a minimum of 250 microns of residual stromal thickness should be left under the flap after LASIK surgery to avoid corneal ectasia.

Currently, most LASIK surgeons prefer to leave 275-300 microns of residual stromal bed for more safety and also to allow for LASIK enhancement (retreatment), should this be necessary.

How Residual Stromal Bed Thickness is calculated?

Residual Stromal thickness is calculated by taking the central corneal thickness before LASIK and subtracting the flap thickness and the calculated ablation depth for the particular refraction.

For example, if your central corneal thickness is 550 microns, the flap thickness is estimated to be 160 microns, and the ablation depth for your refraction is 60 microns, the residual stromal bed thickness would be 550 – (160 + 60) = 330 microns.

Can I Have LASIK if I have a high prescription and thin cornea?

If you have a thin cornea and a high degree of refractive error to be corrected, it may not be possible to leave the minimum 250 microns of residual stromal bed under the flap.

Sometimes, your surgeon can overcome this problem by creating a thinner flap, which allows more treatment to be performed while maintaining a corneal bed of at least 250 microns. Thinner LASIK flaps can be created either by the femtosecond laser flap maker during IntraLASIK or some types of microkeratomes during conventional LASIK.

If it is not possible to create a thinner flap, then other LASIK alternatives such as PRK, LASEK or Epi-LASIK might be a better option for you.

What does LASIK stand for?

noreply@blogger.com (LASIK Guider) — Sat, 01 Apr 2023 22:00:00 +0000

LASIK stands for Laser-Assisted In Situ Keratomileusis and is a vision correction surgery that permanently changes the shape of the cornea using an excimer laser. In simple words, LASIK is the technique of using excimer laser to adjust the shape of the cornea to treat vision defects such as myopia, hyperopia and astigmatism.

To learn more about LASIK, and to see if you are a candidate check the full series of LASIK Vision Correction Explained tutorials

Still Waiting for A better LASIK Technology !

noreply@blogger.com (LASIK Guider) — Sat, 01 Apr 2023 14:52:00 +0000

Should I wait until the technology is better to have LASIK?

This question seems to pop up in the mind of everyone considering LASIK eye surgery. And I’m sure that you’ve thought about it.

If you want a simple and straight answer, I will tell you that you could wait!

Why?

Simply because LASIK eye surgery is an elective procedure and you can wait for a more advanced LASIK technology.

But before you stop reading, I want you to think about what you will miss out if you keep postponing your LASIK procedure (i.e. enjoying the freedom from eyeglasses and contact lenses as you wait). You should also keep in mind that the LASIK technology will continue to improve and you could continue to wait the rest of your life without ever having the procedure.

So the important question is whether the technological advances in LASIK eye surgery means an increase in quality of vision, chance of success or patient satisfaction after LASIK.

It is unlikely that for most patients there will be a noticeable difference if they choose to wait. In many cases, time spent waiting for the technological improvements also means less time to potentially benefit from the refractive surgery.

On the other hand, a few patients should wait for more advanced LASIK technologies and your doctor will tell you whether you fall into this group.

LASIK is safe and good enough to have the procedure now. So if you are an ideal LASIK candidate today, there is no need to wait. Future LASIK advances will allow those who are not good LASIK candidates today to undergo the LASIK procedure successfully.

Perfect Vision After LASIK? No Guarantee

noreply@blogger.com (LASIK Guider) — Fri, 31 Mar 2023 16:17:00 +0000

Not all persons who meet medical and ophthalmic criteria for LASIK surgery are necessarily good LASIK candidates for the procedure. Persons who demand perfection and have too high expectations of LASIK vision correction surgery are poor LASIK candidates.

Your final satisfaction with your LASIK procedure outcome depends mostly on having realistic expectations, So before making your decision to have LASIK, be sure to consider the following points:

LASIK Perfect Vision

Although high success rates of LASIK eye surgery are widely reported, LASIK vision correction surgery can’t guarantee perfect vision for every patient. Successful LASIK outcome depends on the individual. Everyone's eyes and vision are unique. What works for others may not work for you. Your LASIK results depend on the way your corneas respond to excimer laser energy and how they heal after surgery.

The Aim of LASIK Eye Surgery

LASIK will almost certainly improve your vision and reduce your dependence on glasses and contact lenses, but glasses may be needed for certain tasks such as driving at night.

LASIK Retreatment (Enhancement):

LASIK Retreatment may be required to get optimal outcomes. A typical retreatment rate is approximately 10%, meaning 90% of patients achieve their vision goals with one LASIK surgery. Retreatment rates will be higher for patients with more extreme refractive errors.

LASIK and Presbyopia:

The surgical correction of presbyopia is still in its infancy. Glasses may be needed for reading when you reach the middle 40s. However, if you are motivated sufficiently, monovision LASIK may be a possibility that can reduce the need for reading glasses. In monovision LASIK, one eye is corrected for distance vision and the other for near vision.

Myopia - Nearsighted Eye

noreply@blogger.com (LASIK Guider) — Wed, 29 Mar 2023 20:02:00 +0000

Myopia, also called nearsightedness or shortsightedness, is a refractive error ( vision defect) of the eye in which with accommodation completely relaxed, parallel light rays entering the eye come to a focus in front of the retina, creating a blurred image.

Structure of the Nearsighted Eye:

In the nearsighted eye, the eyeball is too long or the cornea is too steep (has too much curvature). As a result, the light entering the eye is not focused correctly and distant objects look blurred.

Symptoms and Signs of Myopia (Nearsightedness)

Nearsighted persons have more trouble seeing distant objects as clearly as near objects. This problem is often noticed in school-age children who complain of having trouble seeing the chalkboard. As the eye continues to grow during childhood, nearsightedness typically progresses until about age 20. However, nearsightedness may also develop in adults because of visual stress or health conditions such as diabetes.

Difficulty in seeing distant objects clearly is the only problem in simple myopia. Some improvement of vision occurs if the individual screws his eyes to narrow the palpebral fissure into a slit. This transforms the eye into a pinhole camera, with sharply focused images on the retina, in spite of the error of refraction.

In high degrees of myopia, other symptoms occurs such as discomfort after near work (e.g., reading) and floaters, shadow-like shapes which appear singly or in clusters in the field of vision and occur as a result of vitreous degeneration.

Causes and Types of Myopia (Nearsightedness):

Axial Myopia is the commonest type of myopia, which occur due to an increase in the eye's axial length. The refractive power of the cornea and the lens is normal. It can be subdivided into:

Simple Myopia, also known as non progressive myopia, starts around the age of 12, gradually increases and stops by age 21 years. It rarely exceeds 6.0 diopters (the measurement unit of refractive power).
Degenerative Myopia, also known as malignant, pathological, or progressive myopia, starts around the age of 7 and continues to increase throughout life. It is characterized by marked retinal changes and associated with a high refractive error (may reach 15 to 25 diopters ).
Congenital Myopia, also known as infantile myopia, is very rare and present at birth and persists through infancy without progression.

Refractive Myopia occurs due to an increase in the refractive power of the eye and can be subdivided into:

Curvature Myopia is attributed to increased curvature of one or more of the refractive surfaces of the eye, especially the cornea.
Index Myopia is attributed to changes in the index of refraction of one or more of the ocular media, especially the lens .

Diagnosis of Myopia (Nearsightedness):

Myopia is detected with a vision test and refraction performed by ophthalmologists or optometrists. It is measured in diopters by the strength or optical power of a corrective lens that focuses distant images on the retina. A large number of persons with nearsightedness also have some degree of astigmatism, which can also cause blurring of vision.

Treatment of Myopia (Nearsightedness):

The treatment for myopia depends on several factors such as the patient’s age, activities, and occupation. There are many options available for correction of myopia. It is most commonly corrected through the use of corrective lenses, such as glasses or contact lenses. The corrective lenses have a negative optical power (i.e. are concave) which compensates for the excessive positive diopters of the myopic eye. Additionally, there is a growing number of refractive surgery procedures (e.g.,LASIK) which can be considered for permanent correction of mild to moderate degrees of myopia in adults.

For people with higher levels of myopia, other refractive surgery procedures are now available; one of these procedures is implanting a small lens with the desired optical correction directly inside the eye (Visian ICL and Verisyse).

Alternatives to Lasik Eye Surgery

noreply@blogger.com (LASIK Guider) — Tue, 28 Mar 2023 18:52:00 +0000

LASIK eye surgery is currently the most popular refractive surgery procedure performed worldwide for correction of shortsightedness, farsightedness and astigmatism. However, you should know that alternate procedures are available for correction of refractive errors. If you are not a LASIK candidate, these procedures become valuable options for you.

Radial Keratotomy (RK)

Radial Keratotomy was the first commonly practiced and recognized refractive surgery procedure. In this procedure, a number of radial incisions are made in the periphery of surface of the cornea. The rapid healing process flattened the cornea and reduced shortsightedness. However, since the introduction of excimer laser procedures, RK became less popular. More details about Radial Keratotomy Surgery.

Automated Lamellar Keratoplasty (ALK)

Automated lamellar keratoplasty involved removing layers of the cornea, replacing the external layer after an underlying layer had been removed. This procedure was used to correct myopia and rarely used after laser surgery was introduced.

Photorefractive Keratectomy (PRK)

Photorefractive keratectomy involve removing the outer layer (epithelium) of the cornea, then the excimer laser is used to reshape the underneath layer (stroma). During the healing process, the epithelium returns to become the outer layer and myopia is reduced.

Laser Assisted Sub-Epithelium Keratomileusis (LASEK)

Laser Assisted Sub-Epithelium Keratomileusis is a procedure that also changes the shape of the cornea using an excimer laser to remove the tissue from the corneal stroma, under the corneal epithelium.

Epikeratome-laser Assisted Keratomileusis (Epi-LASIK)

Epi-LASIK is a new method similar to LASEK performed using an epithelial keratome, but with better results than for some people.

Limbal Relaxing Incisions

Limbal relaxing incisions is used to correct small degrees of astigmatism by making incisions near the outer border of the iris.

Astigmatic Keratotomy (AK)

Astigmatic keratotomy is an extension of the relaxing incision procedure and is similar to radial keratotomy but the incisions are made in a way to make the cornea more spherical. Mild to moderate degrees of astigmatism can be corrected by this procedure.

Laser Thermal Keratoplasty (LTK)

Laser thermal keratoplasty is a refractive surgery procedure that utilize Holmium laser to flatten the central cornea for correction of mild degrees of hyperopia. This technique can also be used to improve presbyopia; however, the laser is expensive and now is rarely used.

Conductive Keratoplasty (CK)

Conductive keratoplasty is a non-laser procedure that uses radiofrequency (RF) energy to produce shrinking of corneal tissues by heat, which changes the corneal shape. This procedure can be used for the correction of a small amounts of myopia and hyperopia, or to bring on myopia for the correction of presbyopia.

Intrastromal Corneal Ring Segments (Intacs)

Intrastromal corneal ring segments are very small semicircular rings made of plastic (PMMA) and placed within the cornea to corrected small degrees of myopia not combined with astigmatism.

Phakic IOLs (Implantable Lenses)

Phakic IOLs may be used to correct high nearsightedness by implanting a small lens with the desired optical correction directly inside the eye.

Clear Lens Extraction

Clear lens extraction may be an option when corneal refractive surgery exist is not suitable. The surgery is essentially the same as for cataract removal, though the accuracy of the biometry and lens power calculation is most critical to produce the ideal refractive result.

Hyperopia - Farsighted Eye

noreply@blogger.com (LASIK Guider) — Mon, 27 Mar 2023 20:14:00 +0000

Hyperopia, also known as farsightedness, longsightedness or hypermetropia, is a refractive error (vision defect) of the eye in which with accommodation completely relaxed, parallel light rays entering the eye come to a focus behind the retina, instead of directly on it, creating a blurred image.

Structure of the Farsighted Eye:

In the farsightedness eye, the eyeball is too long or the cornea is too flat (has less curvature). As a result, the light entering the eye is not focused correctly and near objects look blurred.

Symptoms and Signs of Hyperopia (Farsightedness):

Farsighted persons usually have trouble seeing objects that are close to them. They also complain of difficulty in concentrating and maintaining a clear focus on near objects and frequent headaches after performing close work.In young age, farsightedness gives rise to no symptoms because the natural accommodation of the eye is strong, correcting mild to moderate degrees of farsightedness. As age advances the power of accommodation becomes less, the farsighted person starts to find difficulty in seeing first close objects, and later both close and far objects.

Causes and Types of Hyperopia (Farsightedness):

Axial hyperopia is due to a short axial length of the eye. Children are born with small eyes, thus they have axial hyperopia (average 3 D ). As the eyes grow they become less hyperopic, till they become emmetropic. If the eye does not reach the proper length, hyperopia will remain. If the eye grows more than normal, myopia will result.

Refractive hyperopia: in this type of farsightedness, the refractive power of the eye becomes weaker due to one of two reasons:

Curvature hyperopia is attributed to decreased curvature (flattening) of one or more of the refractive surfaces of the eye, especially the cornea.
Index hyperopia is attributed to decrease in the index of refraction of one or more of the ocular media, especially the lens.

Diagnosis of Hyperopia (Farsightedness):

Hyperopia is detected with a vision test and refraction performed by ophthalmologists or optometrists. It is measured in dioptres by the strength or optical power of a corrective lens that focuses distant images on the retina. Farsighted persons may also have some degree of astigmatism, which can also cause blurring of vision.

Treatment of Hyperopia (Farsightedness):

The treatment for hyperopia depends on several factors such as the patient’s age, activities, and occupation. Minor amounts of hyperopia are occasionally left uncorrected; however, larger amounts may be corrected with convex lenses in eyeglasses or contact lenses. Convex lenses have a positive dioptric value, which causes the light to focus closer than its normal range.Refractive surgery procedures such as LASIK is another option for adults suffering from hyperopia and wish to see clearly without glasses.

How is LASIK Performed?

noreply@blogger.com (LASIK Guider) — Mon, 27 Mar 2023 15:52:00 +0000

LASIK surgery is a vision correction procedure that aims at permanently altering the focusing power of the eye by reshaping the cornea with the excimer laser light.

LASIK is an outpatient refractive surgery procedure. It is performed under local anesthesia in a same-day surgery center or a surgeon's office. It is performed while you are awake, but sometimes your doctor may give you a mild sedative such as Valium to make you relax. Usually both eyes are operated on at the same time, but if you prefer, it can be done one eye at a time.

LASIK is performed in two steps. The first critical step is to create a flap of corneal tissue. The second step is remodeling of the cornea underneath the flap with the laser. Finally, the flap is repositioned.

Let’s now discuss how LASIK eye surgery is performed step by step.

Eye Preparation for LASIK Surgery

You will lie down in a bed, which is adjusted to exactly line up the eye to be treated with the laser. One of your eyes is covered to reduce distraction.

A few minutes before your LASIK procedure, a number of eye drops will be placed; in the eye to be treated. These eye drops will anesthetize your eye and prevent infection.
A special solution is used to clean around your eyes.
A sterile adhesive cover is used to isolate the eye surface from the eyelids and surrounding face. This also helps retracting the lid margins.
A speculum (eyelid holder) is placed between your eyelids to keep your eyelids wide open and prevent you from blinking during the procedure.
A number of ink marks will be made in your cornea to help realigning the flap correctly at the end of the LASIK procedure.

LASIK Flap Creation with A Microkeratome

No injections are used during the LASIK procedure and you will not feel any pain, only some discomfort may be felt.

A ring-shaped device called a suction ring is applied to your eye. Then a slight pressure will be applied to create suction. This will hold your eye in place. The pressure will be elevated sufficient to cause dimmed vision or even blacking out. Don’t worry; this is normal and required to make an ideal LASIK flap.
Once the eye is immobilized, your doctor will then use device called a microkeratome (a surgical blade) to cut a thin flap of the corneal tissue. An alternative way to create a flap is to use a femtosecond laser flap maker.
After creation of the LASIK flap, the suction ring is removed.
Your surgeon will then lifts the flap, hold it back on its hinge, and dry the exposed tissue.

Excimer Laser Ablation (Laser Corrective Treatment)

The creation of the corneal flap prepares your eye for the second step of the LASIK procedure, where the excimer laser is used to correct your vision.

The laser beam will be focused over your eye and you will be asked to stare at a blinking light. This light will help you to fixate your eyes on one spot, once the laser is started.
In a series of short pulses, the excimer laser will reshape your cornea by removing some tissue from the middle layer of the cornea called the stroma. A computer controls the amount of laser energy delivered to your eye according to amount of treatment required. A tracking device is used to find the center of your pupil, so if your eye moves, the laser will follow and stay with the center.
The flap is replaced back into its original position. There are no stitches.
The LASIK operation is completed.

After LASIK Surgery

After your LASIK surgery, you should expect some common symptoms such as burning and tearing, foreign body sensation, light sensitivity, and discomfort. These symptoms will improve in few days after the LASIK procedure.

You should follow your doctor’s instructions after LASIK surgery and don’t hesitate to call your doctor if suspect a problem.

Now you can watch a LASIK Eye Surgery Video to fully understand how LASIK works.

Astigmatism

noreply@blogger.com (LASIK Guider) — Sat, 25 Mar 2023 20:19:00 +0000

Astigmatism is the condition of refraction when the eye does not have the same power of refraction in all meridians (i.e., unequal refraction of light). Parallel light rays entering the eye will not come to a focus image on one point on the retina.

Structure of the Astigmatic Eye:

In normal eye, the cornea is spherical in shape. Light rays passing through all surfaces of the cornea undergo the same degree of refraction (i.e., refracted equally). As a result, these rays come to be focused exactly on the retina at the back of the eye, creating a sharp image.

In astigmatism, the cornea is oval like a football instead of spherical like a basketball. Most astigmatic corneas have two curves; a steeper curve (has too much curvature) and a flatter one. Light rays passing through different parts of the cornea are refracted by variable amount. This causes light to focus on more than one point at the back of the eye, resulting in blurred vision at distance or near.

Symptoms and Signs of Astigmatism:

In addition to blurring of vision, astigmatism may cause headache, pain in and around the eye, redness of the eyelids margin and tearing. Persons with astigmatism may also try to improve vision by squinting (cross-eyed). In children, it may cause delay in learning and poor schoolwork.

Causes and Types of Astigmatism:

The specific cause of astigmatism is unknown. It can be hereditary and may be present at birth. It can change as with age and may decrease or worsen over time. It can range from mild to severe and often occurs along with other refractive errors as myopia or hyperopia. There are two types of astigmatism:

Regular Astigmatism: here the meridian of maximal and minimal powers are at right angel to each other and the change from the meridian of highest power to that of lowest power is gradual. A toric lens can correct regular astigmatism arising from either the cornea or crystalline lens.
Irregular Astigmatism: Here the meridian of maximal and minimal powers are not at right angel to each other and the change from the meridian of highest power to that of lowest power is not gradual. Irregular Astigmatism can be corrected by contact lenses but cannot be corrected by standard spectacle lenses.

Diagnosis and Treatment of Astigmatism:

Most people have some degree of astigmatism. Small amounts of astigmatism usually do not affect vision and do not require treatment. However, larger amounts require correction with eyeglasses or contact lenses. These will adjust the incoming light so that the images will focus exactly on the retina at the back of the eye. Refractive surgery procedures such as LASIK can also be considered to permanently correct astigmatism by reshaping the cornea.