Anomalous origin and aneurysm of the suprascapular artery: the first case observed

Abstract

A 45-year-old woman was referred to our department having suddenly developed, 9 months earlier, a pulsating mass on the right supraclavicular fossa and torticollis. Colour Doppler sonography and computed tomographic angiography showed the presence of an aneurysm (21 mm in diameter) of the suprascapular artery that had an anomalous origin from the subclavian artery. Thoracic outlet syndrome was excluded. After selective arteriography, the aneurysm of the suprascapular artery was successfully treated with ethylene-vinyl alcohol polymer (Onyx, MicroTherapeutics, Irvine, California, USA), a liquid embolic agent. The patient was discharged on the first postoperative day in good condition. Control colour Doppler sonography at 1 year confirmed the complete thrombosis of the aneurysm sac.

Figure 1

Colour Doppler sonographic view of the suprascapular artery. In this longitudinal view, the patency of the suprascapular artery past the aneurysm (white arrows) is shown: the flow (below the baseline) draws away from the transducer indicating that it is directed to the muscle.

Figure 2

Intraoperative selective angiogram of the innominate artery confirming the presence of a large aneurysm (*) of the suprascapular artery (SSA). The SSA arises directly from the subclavian artery at variance with the usual origin from the thyrocervical trunk (panel A). The thyrocervical trunk (TCT) has an anomalous origin from the posterior surface of the subclavian artery (SA) at the level of the internal mammary artery (IMA), as can be seen on a 45° left anterior projection (panel B). aca, ascending cervical artery; CCA, common carotid artery; CCT, costocervical trunk; ita, inferior thyroid artery; tca, transverse cervical artery; VA, vertebral artery; *suprascapular artery aneurysm.

Figure 3

After superselective catheterisation of the suprascapular artery (SSA) with a 5 French vertebral catheter and a dimethyl sulfoxide-compatible Rebar microcatheter, ethylene-vinyl alcohol polymer (Onyx) is injected slowly via the microcatheter in order to fill up the aneurysm and its side branches. Post-embolisation angiography shows complete suprascapular artery aneurysm exclusion. CCT, costocervical trunk; SA, subclavian artery; VA, vertebral artery.

Figure 4

Schematic representation of the most frequent anatomic pattern of the subclavian artery and its collaterals. aca, ascending cervical artery; CCT, costocervical trunk; IMA internal mammary artery; ita, inferior thyroid artery; SA, subclavian artery; SSA, suprascapular artery; tca, transverse cervical artery; TCT, thyrocervical trunk; VA, vertebral artery.