Szemészet, 1975 (112. évfolyam, 1-3. szám)
1975 / 3. szám
Cryotherapy of herpes simplex keratitis has brought about radical changes in the treatment of this disease, both with regard to the duration of treatment, percentage of cures, recurrences and complications, and with regard to the most sparing action to preserve maximum transparency of the cornea [21]. Although the mechanism of the action of low temperature still remains unknown, we know how to obtain good results, which amount to 96% and more of cures. This is the present state of affairs. However, should the hypothesis be confirmed that cryotherapy acts through liberation of endogenous interferon, the latter, used alone or combined with cryotherapy, could have an important part in the treatment of viral diseases of the cornea [1,2]. Of late, the possibility has presented itself to apply the cryogenic technique for partial restoration of transparency to corneas affected with superficial scars or degeneration. In this field, cryotherapy changes our current views on the possibility of non-operative treatment of corneal scars and dystrophies [20]. Cryotherapy as a method of treating iridocyclitis is becoming of importance since it is able to alleviate the inflammatory symptoms and to speed up the healing of the inflammatory condition of the iris and ciliary body [19]. As far as the treatment of glaucoma is concerned, cyclocryoapplication is used when the commonly accepted operative methods have failed in primary glaucoma, or when the-operation cannot be avoided in secondary glaucoma. At any rate, cryogenic treatment of glaucoma embraces above all complicated glaucoma in old people, inveterate glaucoma and glaucoma associated with aphakia [3, 18]. Cryotherapy has proved particularly useful in treating iris prolapse [14], cystoid blebs (10), haemorrhages into the anterior chamber (28) and vitreous body (12), and burns (24, 33). In numerous diseases of the conjunctiva, cryotherapy gives good results, among others in cases of recent trachoma (4, 33). Current experience has shown that the indications for cryodestruction are rather limited. Cold is applied to the remaining eye only, when the other eye has been removed with histological evidence of retinoblastoma. The application of low temperature alone is confined to small, peripheral tumours; in the treatment of larger and more numerous tumours it is becoming more and more important to combine cryotherapy with radiotherapy (25, 28). Noteworthy is the observation in which an iris tumour, clinically diagnosed as melanoma, was subjected to cryodestruction. After three applications of cold through the iris and sclera, the tumour underwent resorption and disappeared. The case was followed up for more than two years and no signs of recurrence were observed (15). The application of cold to benign tumours of the lids gives good results, but no principles have yet been established to guide the cryogenic treatment of malign tumours of the lids (27). A tendency is observed to apply cryotherapy in early periods of retrolental fibroplasia, in Eales’ disease, diabetic retinopathy, angiomatosis retinae, as well as to use it for removing epithelial cysts from the anterior chamber, for removing non-magnetic foreign bodies, for fixing tissues during enucleation, dacryocystorhinostomy, or during removal of orbital tumours (6). All these are instances of the so-called minor ocular cryosurgery (6), as opposed to the sufficiently established cryosurgery of cataract, retinopexy, or cryotherapy of herjaes simplex keratitis. Extensive clinical experience and observations of distant results will finally determine the value of minor cryosurgery and will indicate in which diseases of the eye it has hold its promise. 180
