Nucl Med Mol Imaging.
2013 Sep;47(3):188-195.
Parametric Cerebrovascular Reserve Images Using Acetazolamide 99mTc-HMPAO SPECT: A Feasibility Study of Quantitative Assessment
- Affiliations
-
- 1Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea. larrycheon@gmail.com
- 2Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Korea.
Abstract
- PURPOSE
Basal/acetazolamide stress 99mTc-HMPAO single-photon emission computed tomography (SPECT) has been widely used for evaluation of hemodynamics; however, qualitative and subjective visual assessment of cerebrovascular reserve (CVR) has been performed in clinical settings. The aim of this study was to generate parametric CVR images and evaluate its feasibility of quantification.
METHODS
Basal/acetazolamide stress 99mTc-HMPAO SPECT data from 17 patients who underwent bypass surgery or percutaneous transluminal angioplasty were used. Spatial normalization was performed and parametric CVR images were generated using relative CVR (rCVR) of each voxel proportional to CVR of the whole brain. Binary parametric maps to show area of relatively reduced CVR were generated also using threshold of rCVR < 90 %. We calculated rCVR of internal carotid artery (ICA) using the parametric CVR images and probabilistic maps for ICA territory. Pre- and postprocedural parametric CVR images were obtained and quantitative rCVRs were compared. The rCVRs were evaluated according to visual grades for regional decreased CVR.
RESULTS
Postprocedural rCVR obtained from parametric CVR images increased significantly from preprocedural rCVR. The rCVR was significantly correlated with visual grades of reduced CVR for each side of ICA territories.
CONCLUSIONS
We generated parametric CVR images for basal/acetazolamide stress 99mTc-HMPAO SPECT. As a quantitative measurement, rCVR obtained from the parametric image was feasibly assessed hemodynamic abnormalities with preserved anatomical information.