Amalric triangular sign and carotid Doppler ultrasonographic findings in central retinal artery occlusion

Abstract

This study aimed to determine the incidence of the Amalric triangular sign (ATS) in patients with central retinal artery occlusion (CRAO) and investigate its association with visual function and carotid Doppler ultrasonography findings. A retrospective chart review was conducted on 21 eyes from 21 cases with complete CRAO. Best-corrected visual acuity (BCVA) and carotid Doppler ultrasonography findings [peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistance index (RI) = (PSV-EDV)/PSV] were investigated. Three patients (14%) exhibited the ATS. BCVA at first visit was significantly worse in ATS-positive than in ATS-negative (P = 0.024). Doppler waveform analysis of the common carotid artery (CCA) showed that ATS-positive patients had a significantly lower EDV [P = 0.009, median 10 (range 9–10) vs. 17 (13–24) m/s] and significantly higher RI [P = 0.021, median 0.80 (range 0.79–0.83) vs. 0.72 (0.66–0.82)] than did ATS-negative. The ATS was observed in three patients with CRAO, who showed worse BCVA at the first visit than did those without the ATS. Carotid Doppler ultrasonography revealed that ATS-positive patients had a significantly higher RI and lower EDV at the CCA than did ATS-negative, indicating steno-occlusive changes in the internal carotid artery.