J. François - Böcker

The purpose of this symposium on light-coagulation is not to show the superi­ ority of the argon-laser-coagulation or, on the contrary, of the classical photo­ coagulation, but rather to see, if possible, which are the respective indications and contraindications for xenon-are-coagulation as well as for argon-laser­ coagulation. So, for instance, the argon-Iaser-coagulator is perhaps more appropriate to treat the lesions at and around the macula and the optic disc, but for the peripheral lesions of the retina the xenon-arc photocoagulator is surely as effective. For the conservative treatment of intraocular tumours, the xenon­ arc-coagula tor is beyond doubt more efficacious than the argon-Iaser-coagu­ lator. We were very happy to have at this symposium Professor MEYER-SCHWICKE­ RATH, the creator and the pioneer of light-coagulation, his coworker, Professor WESSING, and Doctor HUNTER LITTLE, one of the pioneers of the laser-therapy. We thank them very warmly for having brought to us the results of their promi­ nent clinical experiments. After general considerations on laser-photocoagulation, we will have a discussion on macular alterations and their treatment as well as on peripheral retinal vascular or non vascular diseases. The most important part concerns the treatment of diabetic retinopathy. Finally the prevention of complications in argon laser retinal photocoagulation will be reviewed.

The three most striking characteristics of the cornea are: a) Its structure or rather its perfectly regular architectonic, by virtue of which it is transparent. b) The absence of vessels, the cornea being nourished by the perilimbic vessels, the endothelial surface in communication with the aqueous humour and the epithelial surface in contact with the pre-corneal film. c) The very slow turnover of the cells, that is to say the keratocytes, with the result that the metabolism of the cornea is very weak. It is this third characteristic which justifies our present investigation. The keratocytes, which are apparently inactive, have in fact a latent activity. They can be activated by central corneal incisions and also by tissue cultures. Under either of those conditions, the keratocytes become very active, develop all the cytoplasmic organites and produce mucopoly­ saccharides as well as the precursors of the collagen (Fig. 1). In order to study the pathological keratocyte, we chose a storage disease, wherein the catabolism of the mucopolysaccharides is blocked, namely the macular dystrophy of the cornea. We undertook the same investigation both for normal and for pathologi­ cal corneas and studied the keratocyte 'in situ' and in tissue cultures using various microscopical and histochemical techniques. In macular dystrophy, we investigated also the deteriorations secondary to the changes in the keratocytes.

This book comprises the proceedings of the first meeting of the Internatio­ nal Society for Corneal Research, held in Kyoto on May 12 and 13, 1978, on the occasion of the International Congress of Ophthalmology. The Society was founded by Dr. Stuart I. Brown (USA), who has to be congratulated very sincerely for this idea. The cornea, window of the eye, becomes, indeed, more and more important and its diseases more and more frequent. Consequently, cornea research is of the greatest necessity not only to cure but also to prevent the various disorders of the membrane. The scientific program of the meeting, established by Dr. Brown, was outstanding. The limiting membranes, the epithelium as well as the endo­ thelium, the stroma, the corneal transplantation, as well as the graft rejec­ tion, the inflammations as well as the immunological aspects, were discussed by experts in the field. The meeting, which was conducted by Professor Motokazu Itoi, honorary Chairman, and successfully organized by his Japanese colleagues, Professor Nakajima, Professor Mishima and their staff, was as interesting as fruitful and left in our mind the best memory. I am convinced that the ophthalmologists will take a great interest in reading the various papers, which bring the latest advances in corneal patho­ logy. Prof. Jules Franyois President of the International Council of Ophthalmology.

Numerous drugs administered either generally or locally have shown a cata- ractogenic action. From a pathogenic point of view a di,stinction must be made between drugs which modify the transparency of the lens due to accumulation (mer- curic,'silver, gold salts, etc.) from those influencing its metabolism. Among the latter, Triparanol, antimitotic drugs, various phenothiazinic derivates, corticosteroids and certain miotics cause the most significatn dam- age. It is necessary to indicate the most frequent reports which evidence a relationship between a prolonged oestroprogestinic therapy and alterations of the lens transparency. The authors also indicate pathogenic mechanisms which probably cause iatrogenic cataracts. REFERENCES Apponi G., Rinaldi E. & De Simone S. Cataratta monolaterale dopo iniezione endo- carotidea di 2-3-5 Trisetilenimmino 1-4 benzochinone (Trenimon Bayer). Ann. Ot- tal. 90, 224, 1964. Baron J.B., Morel P., Rivollan Y. & Soulairac A.: Incidences ophtalmologiques du traitement prolonge par la chloropromazine associee ou non Ii des troubles cutanes. Agressiologie, 9, (2) 293, 1968. Bryk E.: Generalized argyrosis with involvement oflenses. Klin. Oczna 26,217,1956.Conel E.B. & Kelman C.D.: Ophthalmologic findings with oral contraceptives. Obstet. Gynec. 31,456, 1968. Conklin, Upton & Christenberry & MC.Donald: Citato da Duke-Elder. Radiat. Res. 19, 156,1963. Davidson S.I.: Reported adversa effects of oral contraceptives on the eye. Trans. Oph- thai. Soc. U.K. 91,561,1971. De Long S.L.: Incidence and significance of chloropromazine-induced eye changes. Dis. Nerv. Syst. 29 (3), Suppl. 19, 1968.