[Echography and echo-Doppler in the study of thoracic outlet syndrome. Correlation with angiographic data]

This study was aimed at assessing the clinical utility of conventional and color duplex-Doppler US in the diagnosis of thoracic outlet syndrome. Conventional US and Doppler examinations were performed in a prospective study. The results were correlated with angiographic findings. Thirteen patients affected with thoracic outlet syndrome were studied by means of both conventional US and spectral Doppler flow imaging. Five cases (5/13) had neurovascular symptoms in the right upper limbs, 7/13 in the left upper limbs and 1/13 in both upper limbs. An accessory cervical rib was demonstrated in 2/13 cases (associated with muscular hypertrophy in one case and bilateral in the other), by means of plain films of the spine. Conventional US depicted muscular hypertrophy in 7/13 cases--bilateral in one case and monolateral in 6/13 cases, with marked muscular asymmetry. In 5/13 cases, no bone/muscle anomalies were demonstrated. The patients with an accessory cervical rib and scalenus muscle hypertrophy were seen to exhibit two types of hemodynamic alterations in the subclavian artery--i.e., turbulence and changes in the systolic window with no increase in peak systolic velocity in 5/13 cases with mild stenosis, normal or reduced peak systolic velocity with changes in the reversed flow in 3/13 cases with mild/medium-grade stenosis, either during indifferent position or after dynamic tests. In 2/13 patients with no bone/muscle alterations, turbulence was demonstrated in the subclavian artery. However, in 3/13 cases Doppler US revealed no arterial flow abnormalities--3/13 false negatives relative to mild vascular compression. Selective arteriography demonstrated vascular alterations in the subclavian artery in all cases, with or without Doppler anomalies; while angiography was often positive during hyperabduction maneuvers color duplex Doppler demonstrated hemodynamic alterations at rest with indifferent position of the upper limb. In conclusion, conventional US allowed the evaluation of the thickness of both anterior and middle scalene muscles and of possible muscular asymmetries. Color duplex Doppler US demonstrated primary and secondary alterations in the subclavian artery or vein. Therefore, conventional US, duplex and color Doppler prove to be valuable non-invasive tools in the patients with neurovascular symptoms in the upper limbs and could allow the selection of the cases to submit to arteriography.