|Year : 1983 | Volume
| Issue : 7 | Page : 898
M & J Institute of Ophthalmology, Civil Hospital, Ahmedabad, India
M&J Institute of Ophthalmology, Civil Hospital, Ahmedabad
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Lavingia B. Radial keratotomy. Indian J Ophthalmol 1983;31, Suppl S1:898
| Radial keratotomy|| |
How does one define refractive keratoplasty? It is the employment of technique for deliberate surgical modification of corneal radius of curvature or thickness to effect permanent beneficial change in the refractive status of the eye.
It can be done in two ways: (1) By changing the thickness of cornea-keratophakia and keratomileusis; (2) By changing the curvature of the cornea : This includes (a) wedge resection of cornea. (b) disparate size graft-recipient and (c) radial keratotomy.
The radial keratotomy is done with the view to produce regular peripheral fibrosis to induce flattening of the cornea. About 0.1 mm of flattening of cornea in this way causes change in the refraction by 1 Diopter (Barraauer).
| Material and methods|| |
Experiment was done on rabbit eyes. 14 rabbit eyes were operated and followed up for 4 months during this study.
Keratometrv of each eve was done prior to operation. Four ampoules of atropine was given intramuscularly before giving general anaestheasia. Rabbits require more atropine due to presence of atropine esterase enzyme which causes rapid destruction of atropine than in buman being. Retraction was done after injecting atropine, Na Pantothinate was injected through ear vein for giving general anaesthesia.
Eye was kept open by putting lid sutures, 7X0.2 mm. Cut was made with a corneal trephine in the centre. 16 radial cuts were extended from the margin of the trephine cut upto the limbus by blade breaker and a piece of blade maintaining the same depth. Antibiotic drops were put at the end of operation three times a day for one week. No pad or bandage was applied post operatively.
Refraction and keratometery was done at the end of 1st, 2nd, 4th, 6th, 8th, and 12th week. Change in the refraction and radius of curvature was noted.
| Observations|| |
There was gradual change in the radius of curvature and refraction in the operated eye. At the end of 12th week the mean charge in the radius of curvature was 1.37 mm and refraction became myopic by about 4 diopters. There was no gross astigmatism orgrosslyvisible disfiguring scar on the cornea.
| Conclusion|| |
Surgery for decreasing the radius of curvature of cornea induces hypermetropia to counteract axial myopia upto 4 dioptors.