Retinal thickness measurements in chronic glaucoma and ocular hypertension

The sensitivity of the retinal thickness analyzer (RTA), which is able to measure the thickness of the retina at the posterior pole, was assessed in a group of 21 glaucomatous patients and in 24 patients with ocular hypertension but no visual field defects. Of the glaucomatous eyes, 57.6% had a significant reduction in retinal thickness, and another 30.3% were borderline. In the group with ocular hypertension, 37.5% of the eyes were abnormal, and 45.8% were borderline. With regard to the relationship between the location of the loss of retinal thickness and visual field defects in glaucomatous patients, the following results were found: perfect correspondence: nine cases (27.3%); partial correspondence: 18 cases (54.5%); no correspondence: six cases (18.2%). Since the perifoveal area seems to be the first to be affected by chronic glaucoma, with some improvements, the RTA could become a useful device for diagnosing this disease before the onset of functional damage. However, long-term longitudinal studies are needed to clarify whether patients with ocular hypertension and loss of retinal thickness subsequently develop significant visual field defects.