Szemészet, 1975 (112. évfolyam, 1-3. szám)
1975 / 3. szám
34 eyes incorrect light projection was recorded. Some patients had amblyopia, glaucoma. In many patients the cornea was thinned, ectatic, staphylomatous. In 44 eyes, ultrasonic echography showed absence of the lens or presence of membraneous cataract. Surgical technique consisted of intralamellar dissection of the cornea in its posterior layers, penetrating trephining of leucoma, implantation of keratoprosthesis between corneal lamellae in the trephining opening and its fixation. In the presence of opaque lens, the latter was extracted through the trephining opening or additional limbal incision. In the postoperative period, antibiotics, mvdriatics were instilled into the conjunctival sac; hvdrocortison was administered into the inferior fornix; and other therapeutic measures were also undertaken. As a result of keratoprosthesing, restoration of vision was achieved in 53 patients, and in 30 of them — from 0,05 to 1.0. In the rest 17 patients, restoration of vision could not be achieved due to deep amblyopia, atrophy of visual nerve or other changes in the fundus. The optic results obtained can be regarded as quite satisfactory, because before operation these 66 patients were absolutely blind in both eyes. Although in technical respect keratoprosthesing is not a problem, it is accompained by high number of various complications, which make one be very careful when resorting to this operation. We have observed such surgery complications as perforation of posterior or anterior lamella of the cornea at the time of its dissection. In such cases we have commonly performed transplantation of the corneal disc, 6—7 mm in diameter, which consisted of posterior layers of preserved cornea with endothelium. In the disc, a trephining opening was made which corresponded to the diameter of the optical pivot. The corneal disc was placed on the optical pivot behind the supporting intralamellar plate of keratoprosthesis and together with it inserted between corneal layers. If the vitreous body prolapsed, it was usually not very strong, because Fliring’s ring was used, and the normal level of intraocular pressure restored within the first post operative days. We have observed such early complications as hen rphthalmos — in 2 patients, exudate in the anterior segment of the eye — in 3, growth of corneal epithelium or scar tissue on the optical cylinder of keratoprosthesis — in 13, organization of exudate and lenticular remnants, growth of retroprosthesis membrane — in 24, partial destruction of anterior corneal lamella around the optical cylinder of keratoprosthesis — in 12 and extensive destruction — in 4 patients. The growth of endothelium and retroprosthesis formations were insignificant in most of the cases and only slightly affected visual acuity. In some patients, for elimination of the complications, excision and thermocuagulation of overgrowing tissue as well as discission or removal of retroprosthesis membrane were performed. In 4 patients with extensive destruction of anterior corneal lamella, before discharge form the Institute, the implant was fixed; in one of them keratoprosthesis had to be removed after several unsuccessful attempts to held it in place. Ulceration of anterior corneal lamella and exposure of the fixating portion of keratoprosthesis is the most serious complication, as it can lead to extrusion of the implant. The latter was most commonly observed in eyes with leucomas due burn or with thinned cornea. To prevent extrusion of the implant in such eyes we fix the cornea with superficial or intralamellar graft, using various auto-or hoemotissues (conjunctiva, mucous membrane from the lip, cornea, sclera, cartilage, periosteum, etc.). We fix the cornea either before operation or at the time of prosthesing as well as in the threat of extrusion of the implant. 10 Szemészet 145
