Study IDs determinants of the neuro-retinal rim area

(HealthDay)—Reduced neuro-retinal rim area (RA) is associated with narrow central retinal venular equivalent (CRVE) and higher intraocular pressure (IOP), according to a study published online Aug. 31 in Clinical & Experimental Ophthalmology.

Qing Zhang, M.D., from Beijing Institute of Ophthalmology, and colleagues conducted comprehensive eye examinations, including fundus photograph-based measurements of retinal vessel diameter and Heidelberg retinal tomogram (HRT) measurement of the optic disc, in 6,830 adults (≥30 years).

The researchers found that after excluding those with high myopia or without gradable HRT images, 4,194 non-glaucoma and 40 primary open-angle glaucoma (POAG) patients were evaluated for determinants of RA. Determinants of reduced RA were POAG (P < 0.001), higher intraocular pressure (P = 0.03), higher refractive error (P < 0.01), longer axial length (P = 0.01), CRVE (P < 0.001), lower body mass index (BMI; P = 0.015), older age (P < 0.001), smaller disc area (P < 0.001), and higher trans-lamina cribrosa pressure difference (P = 0.03). Reduced RA was associated with lower cerebrospinal fluid pressure only when age and/or BMI were omitted from the model (P < 0.001).

"In summary, our population based study shows that a reduced optic disc rim area is significantly associated with narrow CRVE and higher IOP or lower cerebrospinal fluid pressure," the authors write. "It adds to existing knowledge and supports the concept of multiple factors (biomechanical, vascular, and others) acting concurrently in different sufficient component causal models to cause optic nerve damage in POAG."