Controversies in NTOS: Is Laboratory Testing Necessary in Patients with NTOS?
The diagnosis of neurogenic thoracic outlet syndrome (NTOS) is made on clinical grounds and affirmed by a positive response to a properly performed scalene muscle block. Numerous laboratory evaluations – including electrodiagnostic, non-invasive vascular, and cross sectional imaging studies – have been used in the assessment of patients potentially harboring neurogenic TOS. However, none has a sensitivity and specificity to a degree that is dependable in making the diagnosis of the condition. Instead, such laboratory tests are useful in ruling out the alternative conditions with which neurogenic TOS may initially be confused.