Thoracic outlet syndrome with subclavian aneurysm in a very young child: the complementary value of MRA and 3D-CT in diagnosis.

Thoracic outlet syndrome (TOS) is rare in childhood. In adults, TOS results in compression of the neurovascular bundle (branches of the brachial plexus and the subclavian artery), but more than 95% of cases present solely with neurologic compression. We present a case of TOS in a very young child and describe the rare finding of subclavian artery compression and post-stenotic aneurysm. The clinical features, imaging workup, and surgical findings are discussed. The combination of three-dimensional MR angiography and CT was of great value in diagnosis and surgical planning.