Automated perimetry in amblyopia: a generalized depreion Original Reearch Article

PURPOE: To quantitate the viual field abnormalitie aociated with amblyopia. METHOD: In a propective tudy, 37 amblyopic patient (11 aniometropic, 13 trabimic, 9 combination, 4 deprivation) performed automated perimetry in each eye uing the Humphrey 30-2 program. Primary outcome meaure were foveal threhold, mean deviation, and average threhold. REULT: When the probability plot were examined, 21 viual field in amblyopic eye were normal, 8 had central cotoma, and 7 had diffue depreion. No focal defect other than mild central cotoma were een. However, the foveal threhold of amblyopic eye wa decreaed by an average of 7.2 ± 8.0 dB (P < .0001) compared with fellow eye; intereye difference in mean deviation (3.2 ± 5.4 dB; P < .001) and average threhold (2.9 ± 5.3 dB; P < .005) were alo een. Thi decreae in enitivity for the amblyopic eye occurred for all type of amblyopia. The depreion in threhold wa greatet at the fovea but wa detectable and ignificant at all eccentricitie of the 30-degree field. The average threhold in the amblyopic eye wa highly correlated with viual acuity (r = .839; P < .001). CONCLUION: Although automated viual field in amblyopic eye typically appear normal, all four type of amblyopia are aociated with a generalized depreion of light enitivity, which i proportionately greatet at the fovea and highly correlated with viual acuity lo. In general, amblyopia i not aociated with any area of focal lo of threhold light enitivity. If a focal defect i preent in the viual field of the amblyopic eye, organic caue of viual lo hould be upected. The Humphrey viual field analyzer TATPAC program (Allergan-Humphrey, Inc, an Leandro, California) may artifactually tranform mall and generalized full-field depreion in a manner that make them appear to be iolated central defect.