Abstract TP133: Assessment of Hemodynamic Compromise by Neuro-Parenchymal Blood-Volume System: Comparison With Acetazolamide Challenged Single Photon Emission Computed Tomography

Abstract

Objective: To investigate whether Neuro-parenchymal blood-volume (PBV) measurements could be used instead of acetazolamide (ACZ)-challenged single-photon emission computed tomography (SPECT) to evaluate hemodynamic compromise in patients with cerebrovascular steno-occlusive disease. Methods: Thirteen patients with unilateral carotid artery steno-occlusive disease were enrolled from April 2018 to June 2019, and the severity of hemodynamic compromise was assessed by Neuro PBV system (syngo Neuro PBV IR, Siemens Medical Solutions, Erlangen, Germany) and acetazolamide-challenged SPECT of the brain. Cerebral blood volume (CBV) was measured using a C-arm flat detector angiographic system. The asymmetry ratio of CBV in the middle cerebral artery (MCA) territory (CBV AR ) was defined as the (CBV on the ipsilateral side / CBV on the contralateral side) х 100 (%). Cerebral blood flow (CBF) was quantified by SPECT using the quantitative SPECT/dual-table autoradiography method. Cerebrovascular reserve (CVR) in the MCA territory was defined as (CBF after ACZ challenge – CBF at rest) / CBF at rest х 100 (%) and classified as reduced (<18.4%) or non-reduced (≥18.4%). Results: Five patients showed reduced CVR. The CBV AR was significantly lower in the reduced CVR group than in the non-reduced CVR group (71.6% vs. 110.0%, P = 0.003). The cut-off value of CBV AR for predicting reduced CVR obtained from analysis of the receiver operating characteristic curve was 99.0% (sensitivity 100% and specificity 87.5%), and the area under the curve was 0.975 (95% confidence interval: 0.906-1). Conclusion: This is the first report to evaluate the correlation between CBV AR measured using the Neuro PBV system and CVR assessed by SPECT. CBV AR is useful indicator for evaluating reduced CVR in the MCA territory, as an alternative to ACZ-challenged SPECT.