Prognostic value of retinal nerve fiber layer thickness for postoperative peripheral visual field recovery in optic chiasm compression

Abstract

Object The authors' objective was to evaluate the predictive value of preoperative axonal loss for peripheral visual field recovery after surgery for optic chiasm compression. Methods Consecutive patients with optic chiasm compression in the period from October 2010 through August 2012 were retrospectively studied. Time-domain optical coherence tomography (OCT) had been performed before surgery. Kinetic automated perimetry had been performed before and after surgical decompression. The area of the peripheral isopter (square degrees [deg2]) was assessed. Postoperative improvement was defined as an increase of 25 deg2 or more. Results Sixty-eight eyes in 34 patients were included in the analysis. In 44 eyes the visual field improved after surgery, and in 24 eyes it was unchanged or worse. Nasal retinal nerve fiber layer (RNFL) thickness was a good prognostic factor for peripheral visual field recovery (OR 1.56 per 15 μm, p = 0.041). Conclusions Peripheral visual field recovery after surgery for optic chiasm compression is predicted by nasal RNFL thickness, which is in accordance with the retinotopy of retinal ganglion cells, as nasal axons decussate at the optic chiasm.