Papillofoveal and papillomacular bundle defects are common in patients with early stage glaucoma and associated with central visual field sensitivity loss, according to research published in Ophthalmology.

Researchers conducted a 3 center study between 2015 and 2018 involving 171 patients (204 eyes) with early stage glaucoma and retinal nerve fiber layer (RNFL) defects. The primary objective was to identify eyes with papillomacular or papillofoveal bundle defects and assess visual field sensitivity abnormalities in these patients. The team performed optical coherence tomography for retinal optical texture analysis (ROTA) and evaluated foveal and macular defects among the cohort. The ROTA identified RNFL defects of the arcuate bundle, papillomacular bundle, and papillofoveal bundle.

The researchers found that the area of RNFL defects comprised an average of 17.0% (range, 1.4%-46.0%) of the 10X7 mm2 region of analysis with the widest defect extending over 111.4° along the Bruch’s membrane opening (BMO) margin. They noted that the topography of RNFL defects tended to localize between 50° and 73° along the superotemporal BMO margin converging with the superior arcuate bundle, and between 296° and 326° along the inferotemporal BMO margin at the point of inferior papillomacular bundle convergence. They observed similar defect patterns regardless of VF mean deviation.


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Overall, the pattern of defects varied, with 45.1% of eyes exhibiting RNFL defects involving the superior and inferior hemiretinas, 31.9% had inferior defects alone, and 23.0% had superior defects alone. Most eyes (57.8%) had two or more defects.

The most frequently observed defect pattern involved the inferior arcuate bundle and the inferior papillomacular bundle (20.6%).

Investigators determined that a majority of eyes had defects involving the papillomacular bundle (71.6%). They also noted defects involving the inferior hemiretina (35.8%), superior hemiretina (15.2%), and a combination of the inferior and superior hemiretinas (20.6%).

The team detected papillofoveal bundle defects in 17.2% of eyes and observed that the inferior arcuate papillofoveal bundle was most frequently affected (33 eyes).

VF defects were associated with arcuate bundle defects (OR, 8.03; 95% CI, 3.22-20.0; P <.001), RNFL defect area (OR, 1.15; 95% CI, 1.06-1.24; P <.001), and RNFL defect angular width at the BMO margin (OR, 1.03; 95% CI, 1.01-1.05, P =.002).

“Through unveiling the diversity of RNFL defects, informing the involvement of the papillofoveal and papillomacular bundles, and bridging the disconnect in structure and function, ROTA has the potential to reset the paradigm in the diagnostic evaluation and management of glaucoma patients,” according to the researchers.

Study limitations include the potential for eccentricity mismatch.

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures. 

Reference

Leung CKS, Guo PY, Lam AKN. Retinal nerve fiber layer optical texture analysis (ROTA): involvement of the papillomacular bundle and papillofoveal bundle in early glaucoma. Ophthalmol. Published online April 22, 2022. doi:10.1016/j.ophtha.2022.04.012