Study of Contralateral Eye of Normal Tension Glaucoma and a Unilateral Visual Field Defect

ABSTRACT

PURPOSE: To study the unaffected fellow eye in patients with normal tension glaucoma and unilateral visual field defect in conventional white-on-white automated perimetry, using scanning laser polarimetry and frequency-doubling perimetry. METHODS: Thirty patients with a unilateral glaucomatous visual field defect detected on conventional perimetry (Humphrey field analyzer) were selected. The contralateral eyes with normal conventional perimetry results were studied using scanning laser polarimetry and frequency-doubling perimetry. Twenty eyes of 20 age- (+/-5 years), sex-, refractive error- (+/-2 D) matched persons without glaucoma were selected as a control group. RESULTS: Of the 30 contralateral eyes, 18 eyes (60%) showed a defect of the nerve fiber layer when evaluated with SLP. In the control group, 2 eyes (8.3%) showed a defect of the nerve fiber layer. Of the 20 contralateral eyes, 14 eyes showed abnormal FDP results. In the 17 control group, 2 eyes (2%) showed abnormal FDP results. CONCLUSIONS: These findings suggest that what appeared to be unilateral visual field defects by conventional white-on-white automated perimetry may in fact underestimate structural as well as functional glaucomatous damage in the contralateral eyes. These results may be important for early detection of glaucoma and future treatment.