J Korean Soc Radiol.  2013 Jan;68(1):9-16.

Comparison of Diagnostic Usefulness of Multi-Channel CT Perfusion and Conventional Brain CT in the Acute Pontine Infarct

• Kim SA
• Lee MS
• Kim MS
• Kim YJ

Abstract

PURPOSE
CT perfusion (CTP) is an important modality in the diagnosis of acute stroke, and the range of its use is gradually expanding from supratentorial to whole brain stroke. We assessed the diagnostic value of multichannel CTP in comparison with conventional CT (CT) in acute pontine infarct.
MATERIALS AND METHODS
CTP and follow-up diffusion weighted magnetic resonance imaging were performed in 74 patients diagnosed with acute pontine infarct among 178 suspicious ones. Diagnostic accuracy of CTP and CT was evaluated and quantitative analysis was performed to define the factors that may influence the detection rate.
RESULTS
In the diagnosis of acute pontine infarct, the sensitivity, specificity, and accuracy of CTP was 56.8%, 91.4%, and 77.0% and of conventional CT scan was 47.3%, 93.3%, and 74.2%, respectively. There was no statistically significant difference. Receiver operation characteristic curve revealed both types of imaging to have diagnostic usefulness (p < 0.01) in acute pontine infarct. Among the factors that may affect the detection rate, infarct volume was found to be statistically significant (CTP: p < 0.01, CT: p = 0.01).
CONCLUSION
This is the first study that analyzed the difference between CTP and CT in the diagnostic accuracy of acute pontine infarction. Both CTP and CT are useful diagnostic tools although CTP seems to have a slightly higher detection rate than CT.

MeSH Terms

Brain
Cytidine Triphosphate
Diffusion
Follow-Up Studies
Humans
Infarction
Magnetic Resonance Imaging
Perfusion
Sensitivity and Specificity
Stroke
Cytidine Triphosphate

Figure

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  Fig. 1 Toggling table technique. A. The scanner obtains images during a single rotation at location upper half location of the object. B. Table moves upward to locate the lower half of the object under the X-ray tube. C. Scanner obtains images during a single rotation at location. D. Table moves 4 cm in the opposite direction to the original position. E. Second cycle of scanning is repeated.

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  Fig. 2 A case of abnormal finding on conventional CT, but not identified by CTP in right pontine infarction. Three days before examination, this 66-year-old man experienced dysarthria and left side weakness. A, B. Early conventional CT scans show abnormal hypodensity (arrow) in the right pons (A: precontrast CT scan, B: enhanced CT scan). C. All CTP maps confirm the absence of perfusion abnormality in the right pons. D. Follow-up DWI of MRI, obtained 1 day after stroke, shows infarction (arrow) in the former ischemic portion of the right anteromedial pons. infarct volume: 0.501 mL, diffusion restriction value: 1893.3 (mean). Note.-CBF = cerebral bloodflow, CBV = cerebral blood volume, CTP = CT perfusion, DWI = diffusion weighted imaging, MTT = mean transit time

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  Fig. 3 A case of positive abnormal finding on CTP and but not identified by conventional CT in right pontine infarction. One day before examination, this 51-year-old man experienced dysarthria and left side weakness. A, B. Early conventional CT scans appear normal in the right pons (A: precontrast CT scan, B: enhanced CT scan). C. All CTP maps show perfusion abnormality (arrow) in the right pons. D. Follow-up DWI of MRI, obtained 1 day after stroke, shows infarction (arrow) in the former ischemic portion of the right anteromedial pons. infarct volume: 0.976 mL, diffusion restriction value: 669.5 (mean). Note.-CBF = cerebral blood flow, CBV = cerebral blood volume, CTP = CT perfusion, DWI = diffusion weighted imaging, MTT = mean transit time

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  Fig. 4 Volumetric measurement of the infarct lesion. Boundary of the lesion was drawn and then the volume of the area was automatically calculated.

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