|Year : 1981 | Volume
| Issue : 4 | Page : 411-413
Corneal transplantation in scleral staphylomas
Department of Ophthalmology, General Hospital, Ernakulam, India
E T Kuriakose
Department of Ophthalmology, General Hospital, Ernakulam
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Kuriakose E T. Corneal transplantation in scleral staphylomas. Indian J Ophthalmol 1981;29:411-3
Scleral staphylomas caused by Rhinosporidium is becoming more and more prevalent in Kerala. This condition was Ist described by the author in 1963. [Figure - 1],[Figure - 2],[Figure - 3],[Figure - 4] shows various clinical manifestations.
Untreated or imperfectly treated conjunctival infection by oculosporidium gives rise to the involvement of the sclera. The sporangium tends to erode the whole thickness of the sclera giving rise to scleral staphyloma. This staphylonia may be in any site of the sclera covered by the lid but not seen in the region of the interpalpebral fissure.
When this fungus affects the balbar conjunctiva covered by the lid, the polypoid growth outward is prevented by the pressure of the lid and the infection spreads along the bulbar conjunctiva and deep towards the sclera, resulting in thinning out or perforating the sclera. It is likely that some enzyme produced by oculosporidum erodes the substance of the sclera. Certain amount of pressure by the lid seems essential for this penetration.
When once the seleral substance is thinned out or perforated the contents of the eye ball are herniated out as a staphyloma. When the perforation is very minute only an aqueous fluid is herniated out and the earliest manifestation of the scleral staphyloma is a persistant chemosis of the conjuctiva not responding to treatment. Such chemotic conjunctiva when excised, is seen as a small punched out hole on the sclera beneath.
Treatment : If the infection is detected when it is confined to the conjunctiva it can be successfully treated by excision of the conjunctiva followed by cauterising the area by 2% silver nitrate.
When scleral staphylomas are formed reduction of the staphylomas and reinforcement of the affected portion of the sclera are essential. Reduction of the staphyloma is possible by letting out the aqueous from the anterior chamber by paracentesis and applying pressure over the staphyloma. Reinforcement of the affected sclera is possible by a transplantation of the affected portion by sclera or cornea. In my earlier 5 cases I used sclera for these transplantations. For this the material used was the rejected sclera after the cornea was used for corneal transplantation. These sclerae are preserved in Glycerine. The results were good. But the cutting out and stitching of the seleral tissue is a little tough and difficult. As I had lot of preserved corneas available I used to cornea itself for transplantation over scleral defect. I found the operation much easier and the result quite gratifying. In the last 3 cases scieral staphylomas I did corneal transplaantation to cure the staphyloma.
Procedure : The infected conjunctive over the scleral staphyloma is completely excised and 2% silver nitrate is touched over the area and then washed out with saline. A para centesis is done at the limbus and as much aqueous as possible is let out simultaneously reducing scleral staphyloma by pressing on it. In smaller staphylomas a well defined circular deficiency is obtained on the sclera by this process. In larger staphylomas it is not possible to obtain a well circumscribed scleral defect as there will be thinning of the sclera over a larger area. Judging from the size of the area to be repaired, a corneal trephine of appropriate size is selected. Using this trephine the area to be transplanted is marked out by cutting through partial thickness of the sclera by a few rotation of the trephine over the sclera. It will be enough if only 0.3 mm depth of the sclera is cut. The thickness cut down need not be of the thickness of cornea to be transplanted. The donor material used is glycerine preserved cornea. Corneal button of appropriate size is cut out using the same trephine and stitched on to the scleral cut made. The corneal button is first anchored to any convenient position of the scleral incision and staphylomatous portion is covered by the button and stitched on to the diametrically opposite side, pressing down the staphyloma by the corneal button. When the corneal button is stitched all round it will be flat with the surface of the healthy sclera all round. Now the conjunctival wound is approximated over the transplanted cornea and sutured. The conjunctival suture alone is removed after seven days.
| Post operative period|| |
Routine antibiotic is given during the post operative period. Diamox is given for seven days after the operation to keep the intraocular pressure down.
The total number of cases operated is only three in the past 9 months. Post operatively the area transplanted appears like a second cornea. But since this area is covered up by the lid it does not produce any ugly appearance.
[Figure - 1], [Figure - 2], [Figure - 3], [Figure - 4]