Transient Angle Obstruction Detected by Anterior-Segment Optical Coherence Tomography and Intraocular Pressure Elevation after Hemodialysis

An 80-year-old Japanese man presented with decreased vision in his right eye (OD) after every hemodialysis (HD) session beginning several months previously. His local ophthalmologist prescribed antiglaucoma medications because of high intraocular pressure (IOP) (38 mm Hg) OD 4 months previously; with treatment, the IOP fluctuated between 6 and 34 mm Hg OD. When hospitalized, the IOP was measured, and the anterior chamber was observed by anterior-segment optical coherence tomography (AS-OCT) before and after HD. Before HD, the IOP levels were 7 mm Hg OD and 8 mm Hg in the left eye (OS). AS-OCT showed marked anterior iris bowing due to circumferential posterior synechia OD. The scan showed irido-trabecular contact (ITC) in the nasal angle and not the temporal angle OD. Immediately after HD, the IOP levels were 28 mm Hg OD and 12 mm Hg OS; AS-OCT showed ITC in the nasal and temporal angles OD. Since the iris bombe and HD-induced increase in the ITC were expected to have caused the IOP spike and blurred vision, posterior synechialysis and goniosynechialysis were performed OD. Postoperatively, the iris plane flattened; no IOP spike was recorded, and the blurred vision after HD resolved. At 22 months postoperatively, the IOP was 7 mm Hg in both eyes (OU). No deterioration of visual acuity and visual field was recorded during the follow-up period OU. IOP spikes can occur during and after HD because of transient anterior chamber angle obstruction in cases with narrow angles. AS-OCT is useful for detecting minor morphologic changes in the anterior chamber angle during HD.