Purchase this article with an account.
C Bowd, TA El Beltagi, C Boden, P Amini, PA Sample, LM Zangwill, RN Weinreb; The Association Between OCT Measured RNFL Thinning and Standard Automated Perimetry Pattern Deviation . Invest. Ophthalmol. Vis. Sci. 2002;43(13):254.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To determine the relationship between areas of RNFL thinning identified by OCT and areas of decreased visual field sensitivity identified by standard automated perimetry (SAP) in eyes with glaucomatous optic neuropathy (GON). Methods: 43 eyes with GON identified by evaluation of optic disc stereo-photographs were included. OCT scans were obtained within 6 months of reliable SAP testing. The location and number of abnormal OCT clock hour RNFL thickness measures (thickness ≤ 97.5% of our normative database, n=99) were compared to the location and number of abnormal visual field zones (Weber and Ulrich, 1991) (SAP PD ≤ 95% of our normative database, n=348). The relationship between the deviation from normal OCT measured RNFL thickness at each clock hour and the average PD in each visual field zone also was examined. Results: RNFL thickness was most frequently abnormal in the inferior (6:00, n=13 eyes, 30%) and inferior temporal regions (7:00, 8:00, 9:00; all n=10 eyes, 23%). The three clock hour regions with mean thickness measurements most deviant from mean normal values were (mean ± S.D.) 7:00 (-33.38 ± 38.01 mm), 6:00 (-30.19 ± 37.24 mm), and 1:00 (-22.31 ± 29.48 mm). The most frequently abnormal visual field zones were in the superior hemifield (zones 14, 15, both 9 eyes, 21%; and zone 13, 7 eyes, 16%). The three least sensitive visual field zones by PD were (mean ± S.D.) zone 14 (-3.51 ± 4.05 dB), zone 15 (-3.34 ± 4.04 dB), and zone 13 (-3.16 ± 5.68 dB). Linear regression results (R2) showed that deviation from normal RNFL thickness at OCT clock hour positions 6;00, 7:00, and 8:00 was best correlated with SAP PD in the superior arcuate / nasal step region. R2 values for these associations ranged from 0.35 to 0.59. These values were approximately 70 to 100 times greater than between clock hour position 6:00 and visual field zone 8 (inferior nasal step region) (R2 = 0.005), where such a correlation is not predicted based on topographic mapping. Conclusion: Localized RNFL thinning, measured by OCT, is topographically related to decreased localized SAP sensitivity in eyes with glaucomatous optic neuropathy.
This PDF is available to Subscribers Only