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The following is a summary of “Peripapillary Versus Macular Thinning to Detect Progression According to Initial Visual Field Loss Location in Normal-Tension Glaucoma,” published in the May 2024 issue of Ophthalmology by Shin et al.

Researchers conducted a retrospective study to determine if thinning of the peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell-inner plexiform layer (mGCIPL) can predict visual field changes in patients with normal-tension glaucoma alongside initial parafoveal scotoma (IPFS) or nasal step (INS). 

They followed 185 early-stage glaucoma eyes for 10 years, dividing them into IPFS and INS groups. Using SD-OCT, they assessed pRNFL and mGCIPL thinning and checked VF progression with event- and trend-based analysis. Kaplan-Meier survival analysis compared VF survival in each VF phenotype, and Cox regression analyses identified VF progression factors. 

The results showed that VF progression was detected in 42 IPFS (n=86) and 47 INS (n=99) eyes. In VF progressors, pRNFL thinning was faster in INS eyes (P<0.01), while mGCIPL thinning was similar (P=0.16). At five years, progressive mGCIPL thinning led to lower VF survival in both groups (all P<0.05). Progressive pRNFL thinning affected VF survival only in INS eyes (P=0.015). Cox regression showed that mGCIPL thinning predicted VF progression in IPFS eyes, while both mGCIPL and pRNFL thinning were significant for INS eyes.

Investigators concluded that mGCIPL thinning is better than pRNFL thinning for early VF progression detection in IPFS eyes but not in INS eyes. The right structural parameter (mGCIPL vs pRNFL) depends on the initial VF defect location. 

Source: ajo.com/article/S0002-9394(24)00214-9/abstract