Abstract
Purpose :
To guide pre-operative assessment and post-operative comparison for macular surgery, a method that combines 10-2 visual fields and optical coherence tomography (OCT) scan images was developed.
Methods :
Three eyes of 3 patients with epiretinal membranes (ERM) and advanced glaucoma who underwent macular pucker surgery were used to develop the approach. Each patient had a 10-2 visual field (VF) and OCT scans both pre- and post-operatively. The 10-2 VF was superimposed onto the probability maps for the retinal ganglion cell (RGC) and retinal nerve fiber layer (RNFL) thickness obtained from OCT cube scans centered on the macula and disc (Fig. 1a). Regions of OCT b-scans associated with areas of pre- and post-operative VF defects were compared using pre- and post-operative macular cube scans (Fig. 1b). Pre- and post-operative optic nerve circle scans were also compared to assess changes in RNFL thickness near the optic disc (Fig. 2a).
Results :
There is a need to account for magnification changes between pre- and post-scans, and this was accomplished by aligning scans via vasculature markings, after appropriate scaling of the post-operative scan. This scaling was also applied to the post-operative VF points and b-scan cross-sections (width) (see Fig. 1b). Examination of OCT regions indicated: 1) improvements in VFs were associated with membrane peel; 2) retinal nerve fiber layer (RNFL) thinning was associated with new post-operative VF abnormalities (Fig. 2a); and 3) epiretinal membrane (ERM) distortion of vasculature resulted in poor blood-vessel matching of pre- and post-operative scans (Fig. 2b) that persisted even after scaling.
Conclusions :
Overlaying 10-2 visual fields on OCT probability maps and examining b-scans is useful in assessing operative approaches and post-operative changes of macular pucker surgery provided changes in magnification are taken into consideration.
This is a 2020 ARVO Annual Meeting abstract.