Telemedicine-Guided Carotid and Transcranial Ultrasound

BACKGROUND AND PURPOSE: Transcranial Doppler (TCD) and carotid duplex (CD) provide rapid and safe screening for stroke patients but are highly operator dependent. We explored the feasibility of telemedicine (TM)-guided TCD/CD administered by a health care provider inexperienced with ultrasound. METHODS: Dual video screens transmitted real-time TCD/CD images and sound to a neurosonographer. TM TCD/CD characteristics were compared with an in-person (IP) examination independently obtained on the same patient. We compared carotid stenosis, thrombolysis in brain ischemia (TIBI) flow grades, and the time spent on testing. RESULTS: We examined 8 subjects with a median age of 51 (31 to 63 range). IP and TM successfully examined 100% of internal carotid and middle cerebral arteries, 50% versus 44% of anterior cerebral artery, and 100% versus 88% of the basilar arteries, respectively. The median time in minutes IP versus TM was 15 (range 10 to 35) and 30 (15 to 50) for CD (P=0.07) and 18 (15 to 30) and 45 (30 to 55) for TCD (P=0.002), respectively. TM correctly identified all normal CD/TCD examinations in 7 subjects. In 1 patient, TM identified carotid occlusion but misread TIBI flow grades in both middle cerebral arteries. CONCLUSIONS: Our pilot study showed the feasibility of TCD/CD by an inexperienced health professional guided by a sonographer via TM. Tests were completed within times comparable to outpatient setting in a vascular laboratory.