Single-photon emission computed tomography in distal field hypoperfusion.

To assess the ability of technetium-99m hexamethylpropyleneamineoxime single-photon emission computed tomography (SPECT) imaging to differentiate distal field hypoperfusion from other stroke mechanisms, 24 patients with acute cerebral ischemia were studied. SPECT scans were read by two physicians according to a preestablished set of criteria for distal field hypoperfusion. SPECT patterns read as "probable" or "definite" for distal field hypoperfusion were found in 42% (10/24); of these, 80% (8/10) had ipsilateral carotid occlusion or high-grade stenosis. Severe carotid stenosis was found in 43% (6/14) with SPECT scans negative for distal field hypoperfusion (Fisher exact test [1-tailed] p = 0.0796). The results suggest that a distal field hypoperfusion pattern on SPECT may identify patients with hemodynamically significant large vessel disease.