Case report: Central retinal artery occlusion following scleral buckling surgery with secondary angle closure and recurrent acute ocular hypertension.

Central retinal artery occlusion (CRAO) is a rare but vision-threatening complication following retinal detachment surgery. We report a man in his late 60s who underwent combined phacoemulsification with intraocular lens implantation and segmental scleral buckling for macula-sparing rhegmatogenous retinal detachment caused by inferotemporal ora dialysis. Shortly after surgery, he developed recurrent ocular pain with marked intraocular pressure (IOP) spikes, anterior chamber shallowing, iris bombe, and secondary angle closure. Approximately 3 h post-operatively, visual acuity deteriorated to no light perception. Fundus examination showed diffuse retinal whitening, a cherry-red spot, and marked retinal arterial attenuation. Fluorescein angiography demonstrated delayed retinal arterial filling, with focal choroidal hypoperfusion, consistent with CRAO with associated focal choroidal hypoperfusion rather than primary ophthalmic artery occlusion. Anterior segment optical coherence tomography showed forward displacement of the intraocular lens-iris diaphragm and angle closure. The patient was treated promptly with repeated anterior chamber paracentesis, topical pilocarpine, topical and systemic IOP-lowering therapy, intravenous mannitol, oxygen therapy, and adjunctive supportive treatment. IOP gradually normalized, and anterior chamber depth recovered. However, visual recovery was limited, with hand motion vision persisting during follow-up. Although the mechanism cannot be proven definitively, the temporal sequence and anterior segment findings suggest that buckle-related anterior segment crowding may have led to forward displacement of the intraocular lens-iris diaphragm, secondary angle closure, and recurrent acute ocular hypertension, thereby contributing to critically reduced ocular perfusion pressure and retinal ischemia. This case highlights the need for urgent reassessment of IOP, anterior chamber configuration, and retinal perfusion when recurrent ocular pain and shallow anterior chamber occur after scleral buckling surgery.