Whole-brain perfusion CT performed with a prototype 256-detector row CT system: initial experience.

PURPOSE To preliminarily evaluate the feasibility and potential diagnostic utility of whole-brain perfusion computed tomography (CT) performed with a prototype 256-detector row CT system over an extended range covering the entire brain to assess ischemic cerebrovascular disease. MATERIALS AND METHODS Institutional review board approval and informed consent were obtained. Eleven cases in 10 subjects (six men, four women; mean age, 64.3 years) with intra- or extracranial stenosis were retrospectively evaluated with whole-brain perfusion CT. Three readers independently evaluated perfusion CT data. The diagnostic performance of perfusion CT was visually evaluated with a three-point scale used to assess three factors. Differences between four axial perfusion CT images obtained at the basal ganglia level (hereafter, four-section images) and whole-brain perfusion CT images were assessed with the paired t test. In four subjects, the interval between perfusion CT and single photon emission computed tomography (SPECT) was 1-17 days (mean, 10.3 days). Correlation between perfusion CT findings and SPECT findings was assessed with the Spearman correlation coefficient. RESULTS Three-dimensional perfusion CT images and axial, coronal, and sagittal whole-brain perfusion CT images were displayed, and the extent of ischemia was assessed. Mean visual evaluation scores were significantly higher for whole-brain images than for four-section images (4.27 +/- 0.76 [standard deviation] vs 2.55 +/- 0.87). The cerebral blood flow ratios of the ischemic lesions relative to normal regions scanned with perfusion CT (x) and SPECT (y) showed a significant positive correlation (R(2) = 0.76, y = 0.44 x + 0.37, P < .001). CONCLUSION Perfusion CT performed with a 256-detector row CT system can be used to assess the entire brain with administration of one contrast medium bolus. Thus, ischemic regions can be identified with one examination, which has the potential to improve diagnostic utility.

[1]  J. Thiran,et al.  Simultaneous measurement of regional cerebral blood flow by perfusion CT and stable xenon CT: a validation study. , 2001, AJNR. American journal of neuroradiology.

[2]  K. Furie,et al.  Acute brain infarct: detection and delineation with CT angiographic source images versus nonenhanced CT scans. , 2007, Radiology.

[3]  R Kozak,et al.  CT assessment of cerebral perfusion: experimental validation and initial clinical experience. , 1999, Radiology.

[4]  D. Altman,et al.  STATISTICAL METHODS FOR ASSESSING AGREEMENT BETWEEN TWO METHODS OF CLINICAL MEASUREMENT , 1986, The Lancet.

[5]  J Fiehler,et al.  Apparent Diffusion Coefficient Decreases and Magnetic Resonance Imaging Perfusion Parameters are Associated in Ischemic Tissue of Acute Stroke Patients , 2001, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[6]  E Klotz,et al.  Perfusion CT of the brain: diagnostic approach for early detection of ischemic stroke. , 1998, Radiology.

[7]  M Murakami,et al.  Regional cerebral blood flow measurement with iodine-123-IMP autoradiography: normal values, reproducibility and sensitivity to hypoperfusion. , 1997, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[8]  M. Prokop,et al.  Reproducibility of quantitative CT brain perfusion measurements in patients with symptomatic unilateral carotid artery stenosis. , 2007, AJNR. American journal of neuroradiology.

[9]  D Comar,et al.  Noninvasive tomographic study of cerebral blood flow and oxygen metabolism in vivo. Potentials, limitations, and clinical applications in cerebral ischemic disorders. , 1981, European neurology.

[10]  Takanori Tsunoo,et al.  Development and performance evaluation of the first model of 4-D CT-scanner , 2002 .

[11]  J R Reichenbach,et al.  Acute stroke evaluated by time-to-peak mapping during initial and early follow-up perfusion CT studies. , 1999, AJNR. American journal of neuroradiology.

[12]  M. Wiesmann,et al.  Dynamic CT perfusion imaging of acute stroke. , 2000, AJNR. American journal of neuroradiology.

[13]  H. Fukuyama,et al.  Significance of increased oxygen extraction fraction in five-year prognosis of major cerebral arterial occlusive diseases. , 1999, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[14]  J. Hatazawa,et al.  Quantitative mapping of regional cerebral blood flow using iodine-123-IMP and SPECT. , 1994, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[15]  S M Davis,et al.  Pathophysiological topography of acute ischemia by combined diffusion-weighted and perfusion MRI. , 1999, Stroke.

[16]  Y Yonekura,et al.  A Multicenter Validation of Regional Cerebral Blood Flow Quantitation Using [123I]Iodoamphetamine and Single Photon Emission Computed Tomography , 1996, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[17]  W. Kaiser,et al.  Hemodynamic assessment of acute stroke using dynamic single-slice computed tomographic perfusion imaging. , 2000, Archives of neurology.

[18]  D Comar,et al.  "Crossed cerebellar diaschisis" in human supratentorial brain infarction. , 1981, Transactions of the American Neurological Association.

[19]  Martin Lauritzen,et al.  Neuronal deactivation explains decreased cerebellar blood flow in response to focal cerebral ischemia or suppressed neocortical function , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[20]  W. Koroshetz,et al.  First-pass quantitative CT perfusion identifies thresholds for salvageable penumbra in acute stroke patients treated with intra-arterial therapy. , 2006, AJNR. American journal of neuroradiology.

[21]  Shinichiro Mori,et al.  Physical performance evaluation of a 256-slice CT-scanner for four-dimensional imaging. , 2004, Medical physics.

[22]  R. Craen,et al.  Dynamic CT measurement of cerebral blood flow: a validation study. , 1999, AJNR. American journal of neuroradiology.

[23]  Miwa Okumura,et al.  [Reduction of radiation exposure in CT perfusion study using a quantum de-noising filter]. , 2004, Nihon Hoshasen Gijutsu Gakkai zasshi.

[24]  Y. Yonekura,et al.  Usefulness of a three-dimensional stereotaxic ROI template on anatomically standardised 99mTc-ECD SPET , 2002, European Journal of Nuclear Medicine and Molecular Imaging.

[25]  H. Aronen,et al.  Detecting the subregion proceeding to infarction in hypoperfused cerebral tissue: a study with diffusion and perfusion weighted MRI , 2003, Neuroradiology.

[26]  V Hachinski,et al.  Identification of Penumbra and Infarct in Acute Ischemic Stroke Using Computed Tomography Perfusion–Derived Blood Flow and Blood Volume Measurements , 2006, Stroke.

[27]  William J. Powers,et al.  Importance of Hemodynamic Factors in the Prognosis of Symptomatic Carotid Occlusion , 1998 .

[28]  K Nambu,et al.  A method of regional cerebral blood perfusion measurement using dynamic CT with an iodinated contrast medium , 1996, Acta neurologica Scandinavica. Supplementum.

[29]  M. Wintermark,et al.  Dynamic perfusion CT: optimizing the temporal resolution and contrast volume for calculation of perfusion CT parameters in stroke patients. , 2004, AJNR. American journal of neuroradiology.

[30]  L. Feldkamp,et al.  Practical cone-beam algorithm , 1984 .