Abstract
Purpose :
Evaluation of progressive changes of the inner retinal layers with OCT has been based on progressive RNFL thinning over the parapapillary region or progressive GCIPL thinning over the macula. We hypothesize integrating the RNFL and GCIPL as a single layer for TPA to be more sensitive than TPA of the individual layers to detect glaucoma progression at similar specificities. In this prospective study, we compared the diagnostic performance of wide-field TPA for detection of (1) progressive RNFL+GCIPL thinning, (2) progressive RNFL thinning, and (3) progressive GCIPL thinning in glaucoma.
Methods :
RNFL and GCIPL thicknesses were measured with a swept-source OCT over 12x9mm2 at 4-month intervals for ≥32 months in 192 eyes of 103 glaucoma patients and 104 eyes of 52 healthy individuals. Serial RNFL+GCIPL/RNFL/GCIPL thickness maps were aligned for TPA with a false discovery rate of 5%. The proportions of eyes with progressive RNFL+GCIPL/RNFL/GCIPL thinning were compared with McNemar’s test. Specificities were determined from the normal group. Survival probabilities of progressive RNFL+GCIPL/RNFL/GCIPL thinning were compared with Kaplan–Meier survival analysis.
Results :
The mean age and spherical equivalent of the glaucoma patients were 56.6±13.4 years and -3.03±4.4D, respectively. 41.7% (80 eyes) had early glaucoma (VF MD>-6dB). The mean follow-up duration was 2.8±0.1 years (range: 2.7–3.0 years). 16.7% (32 eyes) had progressive RNFL+GCIPL or RNFL or GCIPL thinning whereas only 5.7% (11 eyes) and 4.7% (9 eyes) had possible and likely VF progression, respectively, by the EMGT criteria. TPA of progressive RNFL+GCIPL thinning detected significantly more eyes (30 eyes, 15.6%) than TPA of progressive RNFL thinning (11 eyes, 5.2%, p<0.001) and TPA of progressive GCIPL thinning (2 eyes, 1.0%, p<0.001). Survival probability of progressive RNFL+GCIPL thinning was significantly lower than progressive RNFL or GCIPL thinning (p<0.001). The specificities of TPA were 97.1%, 96.1%, and 100.0% for detection of progressive RNFL+GCIPL/RNFL/GCIPL thinning, respectively.
Conclusions :
Wide-field TPA of progressive RNFL+GCIPL thinning is more sensitive than wide-field TPA of progressive RNFL or GCIPL thinning to detect glaucoma progression at similar specificities.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.