Retinal Nerve Fiber Layer Damage in Young Myopic Eyes With Optic Disc Torsion and Glaucomatous Hemifield Defect

To investigate retinal nerve fiber layer (RNFL) status at the opposite hemiretinas of optic disc torsion (ODT) in young myopic subjects with glaucomatous visual field (VF) defects and correlation between its thickness and VF defects using spectral-domain optical coherence tomography (SD-OCT).

We assessed the frequency and characteristics of glaucomatous RNFL defects at the opposite hemiretinas of ODT location (ODT-unaffected hemiretinas) in 59 young myopic subjects presenting with glaucomatous VF defects confined to 1 hemifield, and compared the peripapillary RNFL thickness (pRNFLT) in ODT-unaffected hemiretinas of study eyes with that of 60 myopic controls without ODT using Cirrus HD SD-OCT. Linear regression analyses were performed between the pRNFLT measurements at ODT-unaffected hemiretinas and Humphrey field analyzer VF indices.

Approximately 42% of study eyes with ODT showed glaucomatous RNFL defects at ODT-unaffected hemiretinas. The mean width of RNFL defects was significantly greater in ODT-affected hemiretinas than in ODT-unaffected hemiretinas (P<0.001). The mean pRNFLT in ODT-unaffected hemiretinas of study group (99.9±12.1 μm) was significantly lower than that in the matched hemiretinas of control group (109.8±14.9 μm; P<0.001). Significant correlations were observed between pRNFLT parameters and Humphrey field analyzer indices for each hemiretina with or without ODT in the study group.

Young myopic eyes with ODT and hemifield VF loss often show glaucomatous RNFL defects at both hemiretinas and significantly lower pRNFLT in the ODT-unaffected hemiretinas compared with matched hemiretinas of control eyes. Greater VF loss is associated with more advanced pRNFT loss in ODT-unaffected hemiretinas.