Diagnostic Accuracy of Perfusion Computed Tomography in Cerebral Glioma Grading

To determine the diagnostic accuracy of perfusion computed tomography (PCT) in the grading of cerebral glioma.

Cross-sectional analytical study.

Department of Radiology, Allied Hospital, Faisalabad, from January to June 2014.

All the patients with untreated glioma had an initial non-contrast head CT and then PCT using 128 multidetector CTscanner. Perfusion maps of permeability surface (PS) and cerebral blood volume (CBV) were generated and measured. As control, a second volume of interest was placed in the contralateral healthy cortex. PCT parameters were compared with World Health Organization (WHO) glioma grades.

Fifty patients of 30 - 70 years of age of both genders (mean 45.13 ±5.54), 31 (62%) males and 19 (38%) females were studied. These patients were classified as low-grade glioma group (22 patients) and high-grade glioma group (28 patients). PS showed the sensitivity of 95.45%, specificity of 92.86% and diagnostic accuracy of 94% in differentiating the low-grade and high-grade glioma by using a cut-off value of 3.6 ml/100 g/minute. By using a cut-off value of CBV of 2.08 (ml/100 g) among low-grade and high-grade glioma group, CBV showed the sensitivity of 77.3%, specificity of 89.3%, and diagnostic accuracy of 84%.

The derived parameters (PS and CBV) correlate well with tumor histopathology, differentiating low-grade from high-grade gliomas. PS showed better accuracy for glioma grading.