Evaluation of the whole-field scotopic retinal sensitivity tester in clinical glaucoma practice

We determined the results of routine whole-field scotopic vision testing in consecutive patients with ocular hypertension or glaucoma who underwent Humphrey automated perimetric testing and optic disc examination. In 39 ocular hypertensive patients we found a mean threshold of 16.7 +/- 7.4 dB and in 61 glaucoma patients, 20.7 +/- 7.8 dB. A learning effect was noted in ocular hypertensive (p < 0.05) but not in glaucoma (p > 0.05) patients. No association of scotopic threshold levels was observed to the intraocular pressure, age, race, sex, eye tested, number of glaucoma medicines, visual acuity, pupil diameter, lens clarity, medical history, cup-to-disc ratio, mean defect, or pattern SD (p > 0.05). The average threshold level in 30 control patients was 16.5 +/- 6.3 dB, which was not statistically different from the ocular hypertensive (p > 0.05), but differed from the glaucoma group (p < 0.05). The sensitivity of this test was 77% and the specificity 53.8% in separating glaucoma and ocular hypertensive patients. This study suggests that although diffuse scotopic sensitivity loss occurs in patients with glaucoma, much overlap exists with normal and ocular hypertensive individuals that limits whole-field scotopic vision testing diagnostic capability.