Keratoconus

Some "old" findings about keratoconus revisited - I

2009-09-28T12:37:00.002+05:30

Old belief: Males are predominantly affected by this disease. - Most modern studies with wide bases do not support this. Keratoconus affects both genders in a comparable manner.

Old belief : There is no known precipitating factor for keratoconus. - EYE RUBBING is thought to be a precipitating factor in about half the patients diagnosed with Keratoconus.

Old belief: Allergies are more commonly seen in this group of patients. This stands validated in several newer studies across the world including our own.

Information about keratoconus

2009-05-11T19:50:00.001+05:30

We have put together some information about Keratoconus from various sources into an ebook - pdf format on our website www.corneatransplant.net and www.clearvision.org.in Those of you who are interested may download the free copy from the above sites.

ICL for Keratoconus

2009-04-05T11:46:00.002+05:30

Implantable contact lens (Staar Surgical, Switzerland) is another tool that is being used to help patients of keratoconus with large refractive errors.

This has shown itself to be a useful method in helping patients with advanced keratoconus and high myopia with cylindrical errors (usually in excess of -10 Diopters with upto -6Diopters cylinder)

It helps this class of patients improve the uncorrected visual acuity and allows use fo glasses for the small residual errors.

However, it may not take away all the visual deficits. As we now understand, it can not take care of the higher order aberrations and thus the quality of vision still remains less than ideal. However, it a great step from not being able to do anything at all.

Corneal Cross Linking for keratoconus

2009-02-15T22:38:00.004+05:30

My research work on Corneal cross linking in Keratoconus has been published in the Indian Journal of Ophthlamology. It is available for free access at the following link:
www.ijo.in/text.asp?2009/57/2/111/44515
or
http://ijo.in/temp/IndianJOphthalmol572111-7593375_020633.pdf

New thoughts on keratoconus around the world

2008-12-08T11:46:00.003+05:30

Keratoconus may occur due to an imbalance reactive oxygen species (ROS) and Reactive Nitrogen Species (NOS). The ratio is higher in keratoconus patients. This can be exaggerated by exposure to the UVB, chemicals, and mechanical stress such as that caused by poorly fitted contact lenses.

If this is true then AVOIDING EYE RUBBING can not be overstated. Also treatment for allergies need to be well addressed.

Antioxidative therapy, like the ones currently used in retinal treatment could be a possible future option.

Other details will follow in subsequent posts.

Will I go blind from keratoconus, doctor"

2008-12-07T13:22:00.005+05:30

Over the years, treating hundred of individuals with keratoconus I have found that the fear of going blind of keratoconus is a huge issue for many of my patients.

The issue lies in the fact that a keratoconic patient feels like they are always on a treadmill. Apart from regular eye exams sometimes every three months, the fear of losing lenses and of the lenses no longer fitting and being forced to do a corneal transplant is constantly on their minds.

The best way to cope with this ongoing activity is to just accept it and trust that the practitioner treating them will always keep their interest at heart. Finding a practitioner that understands the issues associated with keratoconus is a matter of finding someone that sees many keratoconic patients.

Every keratoconic patient is unique in their own way, but if time is spent analyzing the problems that come up, the overwhelming majority of problems have very satisfactory solutions.

If you are not seeing a keratoconic specialist just ask! You will find that most practitioners will only be too willing to help you find someone that can help you.

Is cross linking the only management a keratoconus patient needs?

2008-12-07T12:59:00.006+05:30

With the arrival of Corneal Cross Linking for Keratoconus, there seems to be an increasing thought process that all that a keratoconus patient is to get C3R procedure done!!

I have been a service provider in the field of Keratoconus for the last several years and have experience in cross linking too. It seems important to point out to both, patients as well as doctors, that C3R provides only one more tool in the care of keratoconus affected individuals. The role of other modalities like contact lenses, intracorneal rings, Laser related surface treatments, ICL insertion, etc remains useful in visual restoration.

It is important to understand that C3R prevents further deterioration in vision (may be some improvement in vision too) and we still need the other modalities.

Thus physicians interested in this field should acquire a complete understanding of this complex interplay in each patient.

Similarly keratoconus affected individuals should select their centers of care with the overall care in mind. C3R alone is not the panacea for keratoconus.

Corneal Collagen Cross linking with Riboflavin and UVA light for keratoconus: One year results in Indian eyes

2008-11-14T16:29:00.004+05:30

WE are sharing with you our results of Corneal Collagen Cross Linking with Riboflavin in Indian eyes.
To our knowledge this is the first Indian report.

Corneal Collagen Cross linking with Riboflavin and UVA light for keratoconus: One year results in Indian eyes

Abstract
AIM: To assess the results of Corneal Collagen Cross linking with Riboflavin using Ultraviolet – A light for keratoconus at one year in Indian eyes.
METHODS: Sixty eight eyes of 41 patients with progressive keratoconus were included in this retrospective study. All eyes completed six months of follow up and 37 eyes had a one year of follow up. The maximum follow-up was 16 months. Ocular examinations including refraction, best corrected visual acuity (BCVA), corneal topography, were recorded at each visit.
Results: The preoperative values on the day of treatment were compared with postoperative values of the 12 month examination. This showed that BCVA improved at least 1 line in 54% of eyes and remained stable in 28% of eyes Astigmatism decreased by a mean of 1.20Din 47% of eyes and remained stable (within ± 0.50 D) in 42% of eyes.
CONCLUSION: The results show a stabilization and improvement after collagen cross linking in Indian eyes. This suggests that it is an effective treatment for progressive keratoconus.

Dr.Vinay Agrawal
Clear Vision Eye Center
Mumbai
www.clearvision.org.in

What is difference between keratoconus and "common" astigmatism and what do the numbers mean?

2008-11-14T16:25:00.001+05:30

Astigmatism is a common condition where the curvature of one or more of the optical surfaces of the eye (the cornea and lens surfaces) are more "round" in one direction than the other. In "regular" astigmatism the maximum and minimum powers are aligned at 90 degrees to each other while in "irregular" astigmatism they do not align. An egg is a good example of a surface with "regular astigmatism". Keratoconus is a degenerative condition where the cornea thins in affected areas. This can lead to astigmatism - often regular at first but becoming increasingly irregular as the disease progresses.

2008-10-03T19:21:00.003+05:30

People with early keratoconus typically notice a minor blurring of their vision and come to their clinician seeking corrective lenses for reading or driving.

At early stages, the symptoms of keratoconus may be no different from those of any other refractive defect of the eye. As the disease progresses, vision deteriorates, sometimes rapidly.

Vision becomes impaired at all distances, and night vision is often quite poor. Some individuals have vision in one eye that is markedly worse than that in the other eye.

Some develop photophobia (sensitivity to bright light), eye strain from squinting in order to read, or itching in the eye, but there is normally little or no sensation of pain.

2008-09-29T16:33:00.003+05:30

The causes of keratoconus are still unknown despite our long experience with it. There has been no shortage of speculation or study and numerous theories have been proposed.

One scientific view is that keratoconus is developmental (i.e., genetic) in origin. This suggests that it is the consequence of an abnormality of growth, essentially a congenital defect. Another view is that KC represents a degenerative condition. Still a third view is that KC is secondary to some disease process. A less widely held hypothesis suggests that the endocrine system may be involved. This idea gained credence from the usual appearance of the disease because it is generally first detected at puberty.

Heredity influences in KC are suggested by studies that show that approximately 13% of patients have other family members with the disease.

It has been proposed that susceptible corneas exhibit an inability to process reactive oxygen species because they lack the necessary protective enzymes (e.g., ALDH3 and superoxide dismutase). The reactive oxygen species result in an accumulation of toxic by-products such as MDA and peroxynitrites that can damage corneal proteins and trigger a cascade of events that disrupt the cornea’s cellular structure and function. This can result in corneal thinning, scarring, and apoptosis.

Good results with C3R for keratoconus

2008-09-08T11:28:00.003+05:30

a week back we had one of our patients come in for his sixteen month follow up. C3R was done for his progressing kertoconus in the left eye in April 2007. the visual acuity improved from 6/12 then to 6/6 now. The corneal topography showed significant reduction in the irregular astigmatism as well as the Simulate Keratometry reading.

There are many such patients. The results from our practice are now submitted to a peer reviewed journal for publication.

What is keratoconus?

2008-08-25T18:23:00.003+05:30

Keratoconus is a degenerative non-inflammatory disorder of the eye in which structural changes within the cornea cause it to thin and change to a more conical shape than its normal gradual curve. It derives the name from (kerato – cornea and konus – cone)

2008-08-20T14:54:00.000+05:30

What part of the eye is affected in keratoconus?

The cornea is the clear, transparent front covering which admits light and begins the refractive process. It is this clear convex cornea which bends (refracts) a ray of light and slows it down. It also shrinks the light to a manageable size (a little smaller than a one rupee coin). It is this front covering of the eye that is affected in keratoconus.

Keratoconus

2008-08-19T17:53:00.000+05:30

Keratoconus is a problem that affects a large number of people. However, in India, there is hardly any awareness about the disease. People affected with this problem are usually left alone to cope with the effects and are forced to grope for answers. We would like to create awareness groups / support groups to help keratoconus affected individuals cope better with this problem.
Any ideas?