Abstract
Purpose :
To test the hypothesis that early glaucomatous eyes with nasal step defects on 24-2 visual fields (VFs) often have macular damage seen with optical coherence tomography (OCT).[1]
Methods :
216 individuals, including 162 patients with or suspected glaucoma and 54 healthy controls, underwent two baseline 24-2 SITA-Standard VF tests and 9x12mm widefield swept-source OCT scans within 4 weeks. Each hemifield of the 216 eyes was graded for a nasal step based on two definitions: one from the Ocular Hypertension Treatment Study (OHTS) and one we developed that was stricter and more clinically relevant. Figure 1 is a depiction of the minimum (a,c) and maximum (b,d) nasal steps that would satisfy the OHTS (a,b) criteria and our stricter criteria (c,d). Eyes with a nasal step were evaluated for topographical confirmation of the nasal step on OCT retinal nerve fiber layer (RNFL) probability maps. These nasal steps were then evaluated for evidence of macular damage by 2 experts (qualitative approach). For the quantitative approach, a custom R program assessed topographical abnormal structure/function agreement between 24-2 and 10-2 VFs and RNFL and retinal ganglion cell (RGC) probability maps.[2,3]
Results :
For the 216 eyes, there were 11 nasal steps with OCT confirmation (10 eyes). 8 of these 11 replicated on the second baseline VF. Notably, 9 of 11 (82%) had macular damage based on the qualitative OCT method, and 1 of the 2 remaining eyes developed macular damage 14 months later (see black arrows in Fig. 2). Based upon the quantitative approach, 7 of the 11 eyes demonstrated abnormal macular structure-function agreement. In general, 8 of the 11 nasal steps were in the superior VF (inferior retina).
Conclusions :
Early glaucomatous eyes with nasal step defects on 24-2 VF often have macular damage seen with OCT, as predicted given the prevalence of macular damage in eyes with early glaucoma and the proximity of the disc regions associated with the macular and nasal step regions of the VF.[1] Because of the clinical significance of untreated progressive macular damage, eyes with nasal steps on 24-2 VF should be examined for macular damage on OCT RGC probability maps and/or 10-2 VFs.
1. Hood, Tsamis, Bommakanti et al. IOVS, 2019. 2. Tsamis, Bommakanti, Sun et al. TVST, 2020. 3. Hood. PRER, 2017.
This is a 2021 ARVO Annual Meeting abstract.