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Background: Failure of filtering surgery may be related to excessive wound healing in the surgical area. This effect diminishes with the use of antimetabolic agents. Mitomycin-C (MMC) has proved to be the most effective drug to reduce myofibroblastic proliferation in experimental in vivo and in vitro models. To our knowledge, the objective changes induced by mitomycin-C in the size of wound healing areas have not been investigated., Methods: Filtering surgery was performed on both eyes of 40 pigmented rabbits. Preoperatively one of the eyes received MMC (0.5 mg/ml), and the fellow eye received balance salt solution as placebo. Animals were killed on days 6, 15, 30 and 58. Microscopic healing areas were measured by digital procedures. The areas of target and fellow control eyes were compared by the Wilcoxon test., Results: This study showed significant differences (p < 0.05) between treated and untreated groups, the healing are a gradually becoming smaller., Conclusions: Objective methods to quantify the microscopic effects of MMC can be useful to improve our knowledge about the action on this antimetabolite and to enable us to adjust more accurately the timing and dosage when applying the drug in glaucoma filtering surgery.

A study using the monochromatic photography technique to examine the retina of a group of patients with human immunodeficiency virus (HIV) infections in different degrees of evolution and with no history of opportunistic retinal infection revealed the existence of lesions on the level of the retinal nerve fiber layer. The lesions detected included wide, slit-like defects; sector defects; and generalized diffuse atrophies. Both the sector defects and the diffuse atrophies appeared at times to be related to retinal cotton-wool exudates, but at other times they occurred in eyes with no observable retinal pathology. The results of this study can be interpreted as "in vivo" confirmations of the findings obtained by other authors in the postmortem study of optic nerves of patients with acquired immunodeficiency syndrome (AIDS), presenting a generalized degenerative process of the optic nerve with a loss of up to 40% of the axons of the retinal ganglion cells. In some cases, the results obtained in our study directly related the presence of cotton-wool exudates to the production of lesions in the retinal nerve fiber layer, whereas in other cases, the fiber lesions did not appear to be secondary to the cotton-wool exudates. Therefore, a primary lesion of the retinal ganglion cells or of the optic nerve fibers could be considered, as studies by other authors have suggested.

The results obtained with the Argon Laser Trabeculoplasty (ALT) on 196 eyes with an average follow-up period of 5.24 years (maximum 9 years) have been reviewed. Of the 123 eyes treated with 75-115 burns in the 360 degrees of the trabecular meshwork, 71 eyes were successful with a follow-up of 64.3 +/- 28.3 months (mean +/- SD). This treatment reduced the previous anti-glaucomatous medical treatment in 35 eyes (28.5%). The remaining 73 eyes were treated with 40-60 burns in 180 degrees of the trabeculum, 38.4% (28 eyes) were successful therapeutically with a follow-up of 56.5 +/- 23.1 months. The treatment reduced the additional medical treatment in 9 eyes (12.3%). The comparison of these results and the survival curves of both groups showed statistically significant differences in favour of the treatment on 360 degrees of the trabeculum.

Preliminary results of a larger investigation on correlation between Retinal Nerve Fiber Layer Defects (RNFL) and Automated Perimetry (AP) are presented. A group of ocular hypertensive patients was recruited and a cross-section, randomized study was carried out. The group was composed of 54 eyes from 28 patients; 15 men and 13 women, mean age 42.76 year, mean visual acuity 0.95 (Snellen cart) and mean visual defect expressed in diopters was +0.514 (from -2.5 to +5). A total of 17 (31.48%) refractive fields were pathologic according to our criteria, one from a normal RNFL and the others from nerve fiber defects. We observed 6 no reliable RNFL photographs, 18 normal, 11 slits, 6 wedge, 11 diffuse and 2 mixed defects. Comparing RNFL and AP, 53.33% of eyes with fiber defects had abnormal perimetries. The more evolutioned the defect, the larger percentage of abnormal visual fields were observed: 36.36% in slit defects, 66.66% in wedge, 54.55% in diffuse and 100% in mixed ones. Comparing location of defects with location of cluster of decreased sensibility points in visual field, a higher correlation in inferior than superior defects was found.

We operated on 59 eyes with advanced neovascular glaucoma (37 eyes in diabetic patients and 22 eyes in patients with central retinal vein occlusion) using a trabeculectomy technique that includes a simple silicone tube as the draining element. Mean (+/- 1 S.D.) intraocular pressure preoperatively was 57 +/- 8.7 mm Hg. During follow-up periods ranging from one to five years, the mean intraocular pressure decreased to 27 +/- 16.5 mm Hg. Adequate control of intraocular pressure (24 mm Hg or less) was achieved in 37 eyes (63%). Only four eyes required enucleation. Nine silicone tubes had to be removed because of necrosis of the scleral flap and conjunctival perforation or because they were expulsed. Surgery relieved the severe ocular pain even when intraocular pressure was not satisfactorily controlled.

The ophthalmology radioactive phosphorus uptake test has been utilized in the differential diagnosis of intra ocular lesions in 21 patients. In the majority of the cases the diagnosis was histologically confirmed. When the lesion is located in the anterior part of the globe, it is not necessary to make an incision of the conjunctiva to perform the test. If the lesion is located in the posterior segment, the test is performed by the transscleral route, with surgical incision of the conjunctiva and with indirect ophthalmoscopy control when possible. In 3 patients with choroidal hemangioma were results false-positives, observed with inferior P32 uptake to that in patients with choroidal melanomas. One false-negative result was obtained in a patient with a clinical diagnosis of uveal malignant melanoma, histologically confirmed after enucleation of the globe. In all others patients with uveal malignant melanoma results were highly positive.