Adverse effects of topical antiglaucomatous medications on the conjunctiva and the lachrymal (Brit. Engl) response.

BACKGROUND: Increasing evidence indicates that long-term use of topically administered medication can induce changes in the conjunctiva and lachrymal function. METHODS: In order to evaluate changes in the conjunctiva and lachrymal response after prolonged use of topically administered antiglaucoma medications and preservatives found in antiglaucomatous medication solutions (benzalkonium chloride), we tested lachrymal function (Schirmer I., Jones, BUT, Ferning tests) and used the conjunctival impression cytology technique. MATERIALS: A group of patients with primary open angle glaucoma (POAG) receiving topical antiglaucomatous medication were recruited. A second group received only preservative instillations while a control group was formed of similarly aged subjects with no eye disease and was given topical or systemic medical therapy. Excluded from the trial were patients with a history of external eye disease or who had received conjunctival surgery. RESULTS: Tear secretion was reduced against that of the control group in those subjects who received protracted administration of antiglaucomatous eyedrops (timolol and/or pilocarpine). A statistically significant degree of conjunctival metaplasia was associated with long-term use of topical medication. The subjective symptoms reported by those patients receiving chronic topical antiglaucomatous therapy and the objective observations on them were found to be proportional to the observed tearing response. Changes were more pronounced in subjects who received only benzalkonium chloride. CONCLUSION: Our study results suggest that long-term use of antiglaucoma medication induces changes in both tear film and conjunctival surface. Such changes may be related to the medication or the duration of treatment, but may also be due to the preservatives used in the commercial product.

Cyclosporine C: a study of wound-healing modulation after trabeculectomy in rabbit.

The authors studied the clinical and histological effects of cyclosporine instilled after filtering surgery. Its efficacy and variety of advantages compared to other antimitotic agents encourage its use.

The relationship between pupil diameter and decentration in myopia.

Since optical zone centration is of such importance in refractive surgery, we have studied, with a computer-aided videopupillograph, the problem of identifying it in myopes. The findings of pupil centre shift as a function of pupil diameter and degree of myopia are reported in two groups of myopes (low and medium) and a control group. Results indicate that the amount and direction of decentration vary according to pupil diameter and degree of myopia. No generally valid instructions can be laid down and each case must be treated on its merits.

[Changes in adrenergic innervation of the choroid during aging]. / Modifications de l'innervation adrénergique de la choroïde pendant la sénescence.

BACKGROUND: Aging causes loss of neurons and adrenergic nerve termination in various human organism systems and apparatus. The aim of this work is the observation of qualitative and quantitative differences in the orientation and density of the human choroid adrenergic innervation in relation to age. METHODS: The choroid specimens were taken from the corresponding sectors of the eyeballs of four patients aged between 70 and 75 years and patients aged between 40 and 45 years. The glyoxilic method of Furness and Costa (1975) was used. RESULTS: The location and orientation of the adrenergic fibres was similar in the adult and aged patients. However, the fibres are clearly fewer in number, less rich in varicosity and have reduced fluorescence. In the suprachoroid lamina thickness and in the vascular layer, the adrenergic synaptic contacts with the melanocytes are fewer in number, as are also the SIF-cells (small intensely fluorescent cells). CONCLUSIONS: With age there is a significant reduction of the orthosympathetic innervation of the human choroid. This fact could explain some physiopathological aspects of the choroid circulation and blood flow and, therefore, play a part in ocular pression variations.

Conjunctiva and subconjunctival tissue in primary open-angle glaucoma after long-term topical treatment: an immunohistochemical and ultrastructural study.

BACKGROUND: Primary open-angle glaucoma is commonly treated with long-term hypotensive medical therapy. When this approach becomes inadequate, therapy proceeds with surgery. The present study investigates morphological changes in the conjunctival and subconjunctival tissues induced by short- and long-term topical medical therapy of primary open-angle glaucoma. METHODS: Comparisons were made between biopsy specimens from glaucomatous patients, who received specific eyedrop therapy (timolol and pilocarpine) for various periods of time, and control patients with no conjunctival pathology or topical treatment. Histological, immunohistochemical and ultrastructural parameters were investigated. RESULTS: The morphometric analysis of histological sections and immunohistochemistry (anti-fibronectin antibody) in medium- and long-term therapy patients showed: (a) significant increases in the thickness and number of epithelial cell layers; (b) significant increases in the fibroblast density in both subepithelial and deep connective tissue; and (c) a more compact connective tissue, richer in collagen fibers arranged in whirls, with some inflammatory elements. These findings were confirmed by the ultrastructural analysis. In the same patients, the other immunohistochemical parameters investigated (anti-HLA-DR, anti-CD1a, anti-CD4, anti-CD8, anti-IL2 and C3b antibodies) revealed a tendency to chronic inflammation. Following specific surgery, this tendency manifested itself in a diffuse immune response, especially in those patients who underwent medium- and long-term medical therapy. CONCLUSION: According to these results, antiglaucomatous surgery should be rehabilitated and considered as an alternative to long-term medical therapy in the first-instance treatment of primary open-angle glaucoma.

Neuronal populations in the spinal cord during ageing.

The sensory and motor fibres of the spinal cord and the relative centres of integration were studied during ageing. Sections of spinal cord and ganglia from C8 to T12 of rats aged 6 and 24 months were treated using several techniques: Nissl, NADPH-diaphorase, and antibodies to enkephalins, substance P and neuropeptide Y. Nissl staining of the C8 segment showed that in the aged rat the dorsal horn was more oblique and narrow, the central canal was enlarged, the cellular density was reduced, and the neurons of the intermediolateral and ventral horns and of lamina IV were smaller. The total number of NADPH-diaphorase-positive cells of C8 segment was similar in the adult and in the aged rats. However, in the aged rat the number of cells was reduced in laminae I, II, III, VII and IX, remained the same in laminae V, VI and X, and was increased in laminae IV and VIII, and in the intermediolateral and intermediomedial horns. In the adult rat, we saw a greater number of cells with a lower expression of the enzyme. The area of the cells in laminae V and IX was reduced in the aged rat. In the C8 segment substance P was present in laminae I and II: in the aged rat the immunoreactivity was reduced and more diffuse. Enkephalins are present in laminae I, II and III, with a reduced immunoreactivity in the aged rat. NPY is present in the central canal in the adult rat and, is also present in laminae I and II in the aged rat.