Comparison of the Photoreceptor Mosaic Before and After Macular Hole Surgery with High Resolution Adaptive Optics Imaging

Abstract

PurposeTo assess the photoreceptor mosaic in patients with idiopathic full thickness macular hole (MH) before and after pars plana vitrectomy (PPV) with adaptive optics enhanced retinal imaging (AO). DesignProspective case series. MethodsProspective cohort study of patients who presented at the Kensington Eye Institute, Toronto, Canada with a diagnosis of macular hole treated with PPV. Exclusion criteria: secondary MH, high myopia (axial length >26.5 mm), media opacity precluding OCT or AO imaging, previous intraocular surgery except for cataract extraction. Imaging using an AO fundus camera (Imagine Eyes, RTX1) was performed preoperatively and 3-months following successful MH repair in both eyes. Cone density (CD), regularity, dispersion, regularity, dispersion, and spacing were measured at 2° and 4° of eccentricity in 4 quadrants (superior, inferior, nasal, and temporal) with pre- and postoperative values compared. ResultsWe included 18 eyes of 9 patients. At 2° there was significant reduction in CD and increase in spacing and dispersion and a non-significant change in regularity post-operatively. Comparison between preoperative and postoperative measurements at 2° mean (Standard Error= SE) were: CD: 14612 ± 3003 and 12280 ± 4632 photoreceptors/mm2 [95%CIs= -2413 to -702] p=0.0004, regularity: 88 ± 7% and 84 ± 12% [95%CIs= -4.67 to 0.04] p=0.054, dispersion: 19 ± 6% and 23 ± 10% [95%CIs= 0.5 to 4.24] p=0.013, spacing: 9 ± 1 microns and 10 ± 2microns [95%CIs= 0.40 to 1.27] p=0.0002; at 4° was: CD: 13377 ± 4339 and 12770 ± 4391 photoreceptors/mm2 [95%CIs= -1368 to 252] p=0.176, regularity:87 ± 9% and 86 ± 12% [95%CIs= -4.65 to 0.08] p=0.74, dispersion: 20 ± 8% and 20 ±9 % [95%CIs= -2.11 to 1.5] p=0.74, spacing:10 ± 2 microns and 10 ± 3 microns [95%CIs= -0.23 to 0.58] p=0.39. ConclusionAdaptive optics imaging allows quantitative assessment of the photoreceptor mosaic pre- and post-PPV in patients with MH. There was a significant change to the photoreceptor mosaic related to the MH at 2° pre- and post-operatively. AO imaging enables high-resolution investigation of the photoreceptor remodeling process following surgery, which may allow for a more thorough assessment of surgical outcomes.