Indications and Outcome of Carotid Doppler Ultrasound: An Ophthalmic Perspective

Abstract

Purpose The purpose of this study was to assess indications and outcome of carotid Doppler ultrasound requested by ophthalmologists from an eye hospital over a period of three years. METHODS This retrospective study was designed to analyse data for all patients referred to have carotid Doppler ultrasound from 1999 to 2001. Colour fundus photograph was used to ascertain diagnosis of ocular condition. Detailed case note analysis was done to correlate patient details, indication, results of carotid Doppler, and status of anti-platelet treatment as well as presence of other risk factors. Results 107 patients were included in the study. 46.7% had normal internal carotid on Doppler while 53.3% patients had stenosis, 22.8% of which were significant. 15 out of 24 patients with retinal artery occlusion had internal carotid artery (ICA) stenosis. 2 out of 6 patients with migraine had significant stenosis. 12 patients had retinal vein occlusion (5 were bilateral), 9 of whom showed ICA stenosis. 14 of 15 patients with retinal emboli had stenosis of ICA. Other diagnoses included anterior ischaemic optic neuropathy, cranial nerve palsy, etc. 42 patients had 1 to 3 risk factors, and 11 patients had more than 3 risk factors. Ophthalmologists started anti-platelet management in 24 patients (42.1%) with some degree of ICA stenosis. CONCLUSIONS Approximately 55% of our patients referred for carotid Doppler were positive for ICA stenosis with nearly a fifth of such referrals having more than 70% stenosis, which is considered to be clinically significant. Our results highlight the importance of such referrals for carotid Doppler for various ophthalmic conditions by the ophthalmologists.