CONTRIBUTION OF NONINVASIVE VASCULAR INVE STIGATIONS (EXCLUDING SCINTIGRAPHY) TO THE STUDY OF REFLEX SYMPATHETIC DYSTROPHY SYNDROME

Noninvasive vascular investigations, including laser Doppler, plethysm ography, and transcutaneous oximetry, are useful for studying microcir culatory abnormalities in reflex sympathetic dystrophy syndrome (RSDS) and have demonstrated decreased blood flow, stasis with increased cap illary permeability, and loss of spontaneous vascular motility. The re active hyperemia test and evaluation of the venoarteriolar reflex prov ide objective data on the course of the syndrome under treatment. Howe ver, the microcirculatory abnormalities, in particular those involving thermoregulation, are not specific for RSDS. Vascular investigations should be performed whenever an underlying venous or arterial disorder is suspected. Duplex ultrasonography is now the gold standard for the diagnosis of deep vein thrombosis and can demonstrate nonocclusive ve nous thrombi. Permanent ischemia can usually be ruled out on the basis of an ankle/arm blood pressure index above 0.5 and a transcutaneous p artial pressure of oxygen above 40 mmHg; arterial duplex ultrasonograp hy and arteriography are unnecessary in most instances.