Imaging Diagnosis of Subclavian Steal Syndrome

Purpose: To evaluate the imaging manifestations and diagnosis value of color Doppler ultrasound,CT angiography(CTA) and contrast enhancement MR angiography(CE-MRA) in subclavian steal syndrome(SSS).Methods:Thirty-two SSS cases whose diagnosis were made based on retrograde flow in vertebral artery on color Doppler ultrasound images and clinical manifestations were enrolled in our study.Fourteen cases were examed with CTA,other 18 cases were examed with CEMRA.The imaging manifestations of all cases of SSS were analyzed.Results: Retrograde flow in vertebral artery was demonstrated during systole and antegrade flow during diastole in 24 cases.Retrograde flow in vertebral artery was demonstrated during both systole and diastole in 8 cases.But it was difficult to demonstrate the initial segment of anonyma and subclavian artery by color Doppler ultrasound.Fourteen cases were examined with CTA which indicated the presence of artery variation in 1 case and moderate or severe stenosis of the initial segment of subclavian artery in 13 cases.Other 18 cases were examined with CE-MRA which indicated severe stenosis of the initial segment of subclavian artery including a case with Takayasu arteritis and a case with stenosis of the initial segment of bilateral subclavian arteries.Conclusion: SSS could be diagnosed by color Doppler ultrasound,but it is difficult to define the etiology.Both CTA and CE-MRA could define the etiology reliably.The application of combination of color Doppler ultrasound and CTA or CE-MRA could diagnose SSS more completely.