Color Doppler sonography findings in patients with subclavian steal syndrome

الملخص EN

Background : Diagnosis of transient ischemic attack within the territory of vertebral arteries is difficult owing to diversity of clinical symptoms.

CT scans or MRI may be of little help in arriving at diagnosis.

Although angiography can detect vertebral artery lesions, it is an invasive and expensive procedure.

Doppler echo sonography of the vertebral artery can provide useful information regarding the presence and extent of ischemia, as well as the velocity and flow of blood in the artery.

Patients and Method : This observational case-control study was conducted between 1995 and 1999 at AIZahra Hospital, Isfahan, in order to investigate the status of vertebral artery in patients with transient ischemic attacks within the perfusion territory of the vertebral arteries.

Carotid artery diameter, as well as the velocity and blood flow were measured by Doppler echo sonography in 100 patients presenting with vertebrobasilar artery insufficiency and 100 controls.

Results : Mean diameter of right common carotid, left common carotid, right vertebral and left vertebral artery in the control group measured 6.8 mm, 6.9 mm, 3.3 mm and 6.0 mm.

Vertebral artery blood flow in the case group was significantly higher than in the control group (P < 0.005).The ratio of measured parameters in the two groups also showed significant differences between the two groups (P > 0.001).

The carotid/vertebral ratio index was also significantly different (P > 0.001).

Discussion : The sensitivity and specificity of the aforesaid indices in detecting vertebrobasilar artery ischemia measured (77.8 % and 90% respectively) suggests that Doppler sonography of carotid and vertebral arteries is a reliably sensitive and specific method for detection of ischemia within the perfusion territory of the vertebral arteries.