What is Keratoconus?
Keratoconus is a progressive ectasia or thinning of the cornea, which is accompanied by an increase in the curvature of the cornea, making it irregular and steep. The internal bonds linking the different layers of the cornea are weakened, due to genetic or inflammatory conditions. It is often associated with allergy of the eye and increased eye rubbing.
How is it diagnosed?
Patients of Keratoconus usually complain of frequent change in their spectacle powers or sudden increase in cylindrical spectacle power. In early stages, it can easily be missed if the patient is not made to undergo a detailed evaluation. This involves doing a special scan for the patient- called Corneal Topography/Pentacam
The cornea is mapped with the help of a specialized machine called Topography, which basically helps provide an idea of the contour and shape of the cornea, with highly precise point to point data on the curvature and thickness and different points on each cornea.
Currently, the mainstay of treatment for Keratoconus includes glasses and / or specially designed rigid gas permeable contact lenses which offer good quality of vision. In advance cases, visual improvement in keratoconus can be achieved surgically by placement of intracorneal rings, topography guided ablation treatments and corneal grafting. Collagen Cross Linking or (C3R) is a new modality of treatment that aims to arrest progression of keratoconus.
What is Collagen crosslinking ?
The corneal collagen is crosslinked with the help of ultraviolet rays ( UVA ) and a photosensitiser, Riboflavin , thus enhancing the rigidity of corneal tissue and stabilizing the condition
Who is a suitable candidate for Collagen crosslinking ?
Patient must be a proven case of keratoconus with documented progression of the disease.
Patient’s corneal thickness must be at least 400 microns.
Patient should not be pregnant or nursing.
How is Collagen crosslinking performed ?
The treatment is performed under topical anaesthesia with the patient in a lying down posture in the sterile environment of the operating room. The patient’s corneal epithelium is gently removed, following which Riboflavin solution is applied every 5 minutes for the first half an hour. Thereafter the patient’s cornea is exposed to UVA light for half an hour. The treatment is painless and lasts for an hour, at the end of which the eye is patched
What is accelerated crosslinking?
Accelerated Crosslinking involves use of latest equipment in crosslinking which delivers same energy in shorter period of time making the total procedure to be over in less than half an hour .This treatment offers less patient discomfort and early recovery.
When can the patient resume normal routine ?
After the treatment, patient will be able to resume work within 3 to 4 days.Care should be taken to avoid entry of water into the eyes during this period.The use of contact lenses may be resumed 6 weeks after treatment.
How often must the patient come for follow up ?
The surgeon will examine the patient’s eye daily for the first 2 to 3 days until the epithelial healing is complete. Eye drops will be used for 4 months. Patient will have to come for follow up at 6 weeks, 3 months, 6 months, 1 year and 2 years after the procedure.
Can both eyes be treated at the same time?
If both eyes are suitable for Collagen crosslinking, the treatment is performed on one eye at a time .The timing of treatment of the second eye is best decided in consultation with your ophthalmologist.
What are the possible side effects of the procedure?
A foreign body sensation, irritation or watering accompanied by pain is not uncommon on the day of treatment. Analgesics for relief from pain will be prescribed , and the pain usually subsides within 24 hours. Dryness of the eyes frequently follows this treatment and may last for 6 to 8 months. Tear lubricants are therefore recommended for the period.