Microperimetry-guided inverted internal limiting membrane flap site selection to preserve retinal sensitivity in macular hole with glaucoma

Abstract

Purpose: In cases of macular hole (MH) that is difficult to close, including large, chronic, or highly myopic cases, the inverted internal limiting membrane (ILM) flap technique is often preferred and yields favorable surgical outcomes as compared to those yielded by conventional ILM peeling. However, no consensus exists on the optimal location and area for peeling and inverting the ILM, since multiple alternative methods have been reported alongside the original method. Several adverse effects associated with ILM peeling have been documented, including mechanical impairment of the retinal nerve fiber layer and decreased retinal sensitivity. Particularly, when glaucoma is concomitant, the retinal nerve fiber layer is fragile, raising concerns about a decrease in retinal sensitivity. Consequently, in patients with large MH alongside glaucoma, the goal is to select a procedure that maximizes the closure rate of the MH while minimizing any negative impact on glaucomatous visual field impairment. However, a technique for this purpose has not yet been validated. Observations: A woman in her 60s presented with visual impairment (20/50), metamorphopsia, and central scotoma of unknown onset in the right eye. A full-thickness MH accompanied by epiretinal proliferation (EP) was identified, with a minimum diameter of 506 μm. Although a retinal nerve fiber layer defect was not evident on ophthalmoscopy, thinning of the ganglion cell complex (GCC), extending from the superotemporal aspect of the optic disc, was observed on optical coherence tomography. Both microperimetry and static visual field testing revealed reduced retinal sensitivity in the thinned GCC areas. A pars plana vitrectomy combined with cataract surgery was performed to address her condition. The EP was embedded into the foveal cavity. On the basis of the microperimetry results, the ILM within the absolute scotoma region was peeled on the superotemporal side of the fovea to create a flap, which was then placed over the MH. A gas tamponade was applied, and the patient was maintained in a prone position postoperatively. The MH was successfully closed after the surgery, resulting in visual improvement (20/25). No decline in retinal sensitivity after the surgery was observed. Conclusions and importance: Determining the location and area of the inverted ILM flap on the basis of microperimetry results is a promising patient-tailored strategy for treating MH concomitant with glaucoma while preventing further ILM peeling-associated reduction in the retinal sensitivity.

Keywords

• Macular hole
• Glaucoma
• Inverted internal limiting membrane flap
• Vitrectomy
• Microperimetry