EVALUATION OF CEREBRAL VASOSPASM IN PATIENTS WITH SUBARACHNOID HEMORRHAGE USING SINGLE-PHOTON EMISSION COMPUTED-TOMOGRAPHY

Cerebral vasospasm (CVS) occurs as a result of the breakdown in cerebr al autoregulation mechanisms. Because cerebral vasospasm can occur aft er subarachnoid hemorrhage (SAH), it is important to evaluate borderli ne perfusion. Evaluation of borderline vascular insufficiency is impor tant to reduce ischemic complications. In this study 25 patients with SAH were investigated by somatosensory evoked potentials (SEP), comput ed tomography (CT), digital subtraction angiography (DSA) and single p hoton emission computed tomography (SPECT) in order to predict borderl ine ischemic areas. Clinical grades were also correlated with these in vestigations. Thirteen patients had symptomatic vasospasm and 15 patie nts had angiographic vasospasm. SPECT showed hypoperfusion in 22 out o f 25 patients. CT predicted CVS in 8 of these 22 patients. Our study s hows that brain perfusion SPECT is a non-traumatic, non-invasive, non- allergic, inexpensive method for the prediction of cerebral vasospasm. We conclude that brain SPECT with Tc-99m HM-PAO is an accessible tech nique that can demonstrate varying degrees of regional tissue hypoperf usion in patients with delayed ischemic deficits due to CVS following SAH.