Whereas the values of 120/70 mm Hg are universally recognized as being normal for the parameter of systemic blood pressure, the value for ‘normal intraocular pressure’ remains very vague. Indeed, values between 7 and 21 mm Hg are often considered normal. However, a careful review of the literature and original data reported here suggest that the intraocular pressure in normal subjects, although dynamic, is a more accurate parameter than is generally expected. The normal value during the day in healthy, young adults is about 12 ± 2 mm Hg, and it increases by 1mm Hg per decade after 40 years of age.

The levels of alanine, aspartate and glutamine transaminase increase considerably in some diseases. We measured the activity of these enzymes and of the transaminase of 3-hydroxykynurenine, an aminoacid, which acts as a UV lens filter. Alanine and glutamine transaminases (carboxypeptidase) were not detected in normal and cataractous human lenses, and aspartate transaminase was found only in the cortex of normal lenses. 3-hydroxykynurenine transaminase was not found in lenses from persons below thirty years of age, but was found in lenses at about fifty years of age, and in cataractous lenses. Transamination of 3-hydroxykynurenine leads to the formation of xanthurenic acid and its derivatives. These substances appear to be responsible for the increase of lens fluorescence during cataract development.

Dopamine is known to stimulate ion transport in the corneal epithelium. Since epithelium is in contact with tears, we searched for dopamine and its metabolites in tears. Twenty normal subjects participated in this study. Twenty microliters of tears were collected in capillary tubes after trigeminal stimulation and immediately analyzed using high-performance liquid chromatography with electrochemical detection. Dopamine and two of its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), were identified and measured. The mean concentration of dopamine was 8.9 +/- 5.1 ng/ml; DOPAC, 2.2 +/- 1.6 ng/ml; and HVA, 0.55 +/- 0.4 ng/ml. These results permit us to suggest that dopamine is deaminated by monoamine oxidase, then methylated by catechol-O-methyltransferase and that catabolism occurs in the lacrimal gland and perhaps in corneal epithelium. Finally, part of the dopamine involved in ion transport may come from tears.

A case is described having malformation of the anterior chamber with bilateral high IOP combined with multiple ocular anomalies in a 13-year-old girl. Here, embryotoxon posterius, synechiae out to Schwalbe's line, and hypoplasia of the iris stroma in the form of Rieger's anomaly are associated with: myelinated corneal nerves concurrent with appearance of vessels without scleralization, unilateral orbital hypoplasia without microphthalmia and without enophthalmos within the scope of a unilateral facial hypoplasia, bilateral epicanthus with asymmetry of the lid-openings without hypertelorism, bilateral delayed development of the tear ducts, horizontal myopic astigmatism and bilateral relative amblyopia, dental deformation, urogenital malformation, deformation of the joints, slightly delayed mental development, ataxia, normal karyotype. In a chronically alcoholic mother, the association between these systemic and ocular anomalies constitutes a fetal alcohol syndrome. Although the anomalies of other derivatives of the neural crest have already been described in this context, certain of these anomalies, such as malformations of the ectoderm or mesoderm, have not been reported.

Keratoplasty in a calm and avascular cornea usually involves no histocompatibility problem. This is not the case if the recipient cornea is inflamed or vascularized. In such cases, and in those where the donor button has been rejected, HLA matching and particularly the search of HLA DR is important. More than 80 potential kidney donors (160 eyes) are tested each year at Zurich University Hospital. The availability of matched corneas, a certain degree of homogeneity of DR group in our population, and an "anti-DR" action of cyclosporin-A gave us the incentive to perform this study and to place these corneas at the disposal of every Swiss clinic. For this purpose, the HLA groups of high-risk patients must be established and sent to Zurich Eye Bank where these data are regularly compared with matched corneas. Every time an HLA A, B, and especially an HLA DR compatible donor-recipient pair occurs, the clinic involved will be quickly informed. In cases where HLA DR antigens are not compatible, cyclosporin-A should be part of the treatment and in cases where they are compatible, advice would be given to do without it. Since optimal preservation, with the medium used lasts 5 days, there is sufficient time for most corneas with a known HLA group to be grafted on the most compatible recipient.