학술논문

Adduction-Induced Strain on the Optic Nerve in Primary Open Angle Glaucoma at Normal Intraocular Pressure.
Document Type
article
Source
Current eye research. 46(4)
Subject
Orbit
Optic Nerve
Humans
Glaucoma
Open-Angle
Magnetic Resonance Imaging
Eye Movements
Tonometry
Ocular
Prospective Studies
Intraocular Pressure
Adult
Aged
Middle Aged
Female
Male
Biomechanical Phenomena
Biomechanics
normal tension glaucoma
optic nerve
optic nerve strain
Neurosciences
Biomedical Imaging
Eye Disease and Disorders of Vision
Neurodegenerative
Ophthalmology & Optometry
Language
Abstract
Purpose/aimThe optic nerve (ON) becomes taut during adduction beyond ~26° in healthy people and patients with primary open angle glaucoma (POAG), but only retracts the globe in POAG. We used magnetic resonance imaging (MRI) to investigate this difference.Materials and methodsMRI was obtained in 2-mm quasi-coronal planes in central gaze, and smaller (~23-25°) and larger (~30-31°) adduction and abduction in 21 controls and 12 POAG subjects whose intraocular pressure never exceeded 21 mmHg. ON cross-sections were analyzed from the globe to 10 mm posteriorly. Area centroids were used to calculate ON path lengths and changes in cross-sections to calculate elongation assuming volume conservation.ResultsFor both groups, ON path was nearly straight (