Table 2.

Investigations in ATOS, VTOS, and NTOS.

TOS Subtype	Definite Role	Possible Role	Emerging Role
All	Plain radiography (chest/cervical spine) Non-contrast CT/MRI [5,27]	-	-
ATOS	Duplex ultrasound Contrast arteriography Finger plethysmography [5]	CT/MR arteriography with provocative manoeuvres [5,26,28,29,30]	-
VTOS	Duplex ultrasound [5,12,31] CT/MR venography [32] Contrast venography [33]	CT/MR venography with provocative manoeuvres [5,26,28]	-
NTOS	Nerve conduction studies Needle electromyography [5,34] Local anaesthetic injection test [5,35,36,37,38]	-	MR neurography [39,40] Diffusion tensor imaging [41,42,43,44,45] Brachial plexus ultrasound [46,47]