M3 PBL Blog: Radial Keratotomy

Diagnosis

The patient is diagnosed with myopia and astigmatism (uneven cornea surface). Other than that, the eyes are normal, healthy with stable, mild to moderate myopia (up to 3 diopters). This patient will be eligible for Radial Keratotomy (RK) if he/she does not have pathological myopia, in which the eyeball fails to stop growing longer. Degenerative changes caused by severe nearsightedness (high myopia), such as retinal tears and abnormality or disease of the cornea should not be present in the eyes.

Usually, the patient is given the option to choose between several other types of operations. Photorefractive Keratotomy (PRK) and LASIK surgery have replaced RK by popular choice, yet it is still effective in reducing mild myopia.

Process #1

The eye is anesthetised and a ring is fixed to it in order to prevent if properly positioned and flat.

A precision calibrated diamond knife is used to make four to eight incisions perpendicular to the circumference of the cornea. To achieve high efficiency, the incisions usually reach deep into the cornea. This will cause the cornea to flatten and thus change the shape of the lens.

Recovery and results

RK causes more discomfort and requires a much longer time to heal as compared to PRK and LASIK. The results are also more unpredictable. However, the incisions are suspected to never heal entirely. There have been reports of unhealed incisions even after 20 years of surgery. These open wounds allow bacteria to settle and spread, thus causing much more harm like infections and inflammation to the eye. Therefore, patients have to return to doctors frequently for the first year in order to prevent these damages.

Possible Side-effects

-More scattering of light

-Loss of fine depth perception

-Puncture of the cornea

-Infection

-Inflammation

-Glaucoma

This surgery is still being performed albeit less popular than PRK and LASIK.