OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY SHOWS DEEP CAPILLARY PLEXUS HYPOPERFUSION IN INCOMPLETE CENTRAL RETINAL ARTERY OCCLUSION.

PURPOSE To analyze optical coherence tomography angiography images of retinal capillary perfusion in incomplete central retinal artery occlusion. METHODS Case report of a 63-year-old male white patient with transient vision loss in the left eye related to central retinal artery occlusion, secondary to left internal carotid thrombosis. Optical coherence tomography angiography images were captured with Angiovue (Optovue, Inc., Freemont, CA). Retinal capillary bed was segmented into the superficial and deep capillary plexus. Each blood flow angiography image was associated with an en face optical coherence tomography image and an optical coherence tomography B-scan showing the level of segmentation. RESULTS In the left eye, visual acuity was 20/20 five days after transient vision loss. Optical coherence tomography angiography showed a normal superficial capillary plexus but the deep capillary plexus was not distinguishable compared with the right eye, although the posterior pole appeared well perfused on fluorescein angiography. Retrobulbar Doppler ultrasound confirmed a reduced blood flow velocity in the left central retinal artery. CONCLUSION In this case of incomplete and transient central retinal artery occlusion, the deep capillary plexus was poorly visible on optical coherence tomography angiography, which could be due to its elective hypoperfusion and explain the ischemic whitening of the inner nuclear layer, previously described as paramacular acute middle maculopathy. However, the reason why the deep capillary plexus is more sensitive to reduced blood flow in the central retinal artery is not fully understood. In a case of partial central retinal artery occlusion, optical coherence tomography angiography allowed showing elective poor perfusion of the retinal deep capillary plexus.