Thickness of Retinal Nerve Fiber Layer Decreases after Vitreous Surgery for Idiopathic Macular Hole

Purpose: The alteration of the retinal nerve fiber thickness (NFLT) before and after vitreous surgery for a macular hole in cases with or without visual field defects was investigated.Methods: The NFLT of 23 eyes with idiopathic macular hole was measured with scanning laser polarimeter up to 12 months after surgery. The NFLT was divided into superior, inferior, nasal, and temporal quadrants. The mean NFLT of each quadrant was analyzed statistically and compared to the results of visual field tests.Results: In all cases, the NFLT decreased significantly up to 3 months after surgery, but increased gradually up to 12 months. In cases with visual field loss, the thickness of the nerve fiber layer that corresponds to the visual field defect diminished strongly, in contrast with other quadrants. Even in cases without visual field loss, the NFLT decreased significantly a month after surgery, especially in the nasal and inferior quadrants.Conclusion: This study demonstrates that the thickness of retinal nerve fiber layer decreases at least one month after surgery, even in cases without visual field defect. This may suggest the existence of a subclinical complication of vitreous surgery.