Retinal nerve fibre layer photography in glaucomatous and normal eyes

Abstract

The technique of retinal nerve fibre photography has been developed and tested in specialized centres and glaucoma clinics. The usefullness of a modifed technique in clinical practice is the subject of this prospective study. Retinal nerve fibre photos from 41 patients with open-angle glaucoma and 40 normal patients were examined in a blind study, a total of 161 eyes. Photos from 5 eyes were of insufficient quality to allow evaluation. Nerve fibre loss was found in 36% of the normal eyes, 42% of glaucomatous eyes without visual field defects, and 87% of eyes with glaucomatous visual field defects. Sensitivity was 86% and specificity was 62% totally. In the younger patients aged less than 65 years both values were 82%. Photographic nerve fibre loss was found in 69% of normal eyes from patients aged more than 65 years, leading to a low specificity of 31% in this age group.Age related nerve fibre loss and clinically insignificant cataracts were the most obvious causes of non-glaucomatous nerve fibre loss.Primary open-angle glaucoma affects the optic nerve head leading to enlargement of the optic disc cup and visual field defects. Following the description by Hoyt et al. (1973) several investigations have shown retinal nerve fibre loss and reduced sensitivity of the retina as early features of glaucoma.Thorough photographic studies of the retinal nerve fibre layer have been carried out in specialized centres and glaucoma clinics where the technique and evaluation have been improved. This knowledge and skill generally is not immediately available and the general clinical usefulness cannot be deduced from the above-mentioned studies.To clarify this, we have tried to adapt the technique and evaluate some basic results. Material and MethodsThe ophthalmological practitioners from our district were asked to refer patients with primary open-angle glaucoma (POAG) non treated with miotics and without clinically significant cataract. A total of 41 patients (81 eyes, mean age 63.5 years, range 38-82) were included. None had low-tension glaucoma. All eyes had open-angles without visible pathological changes and all had evidence of optic nerve damage in at least one eye.A control group aged 50 years or more was included, in total 40 persons (80 eyes, mean age 63.2, range 50-83). All were in good general health, and without known organic nerve disease, or pathological affection of the eyeball.After informed consent, all subjects completed two examinations. The first examination included measurement of the corrected visual acuity, Goldmann applanation tonometry, gonioscopy, and computerized perimetry using Octopus program 32 without mydriasis. This was followed by mydriatic ophthalmoscopy, slit-lamp examination, repeated tonometry, and Goldman 3-mirror glasses. When either open-angle glaucoma or normality had been confiied the subjects were included in 441

Automated static perimetry and nerve fibre layer defects in glaucoma and controls

“…Several studies have demonstrated retinal nerve fibre loss in glaucoma. Normal eyes showed large variation in the proportion of nerve fibre loss using different photographic technics (Sommer et al 1977(Sommer et al , 1984Quigley et al 1980;Airaksinen et al 1984;Hitchings et al 1987;Pugesgaard et al 1990).…”