Diagnostic accuracy of diffusion-weighted imaging and perfusion-weighted imaging with dynamic susceptibility contrast in differentiating World Health Organization Grade-I meningioma from high-grade meningioma with histopathology as gold standard

Abstract

Abstract Background: Conventional magnetic resonance imaging may not be able to distinguish between the benign and malignant forms of meningioma. It has some limitations such as differentiating the grades of malignant meningioma. Diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) techniques can help to overcome these problems. Aims: The aim of this study was to study the diagnostic accuracy of DWI and PWI with dynamic susceptibility contrast in the differentiating World Health Organization Grade-I meningioma from high-grade meningioma with histopathology as the gold standard. Settings and Design: A hospital-based diagnostic evaluation study was carried out at the Department of Radio Diagnosis, Malla Reddy Institute of Medical Sciences, Hyderabad. Materials and Methods: Fifty cases of suspected meningioma were included in the study. The histopathology was the gold standard in this diagnostic evaluation study. DWI and PWI with dynamic susceptibility contrast results were compared against the gold standard. Statistical Analysis: Sensitivity, specificity, positive predictive value, and the negative predictive value were calculated to study the efficacy of DWI compared to histopathology as the gold standard. Results: The males (24%) were lesser than the females (76%). The female-to-male ratio was 3.2:1. The diagnostic accuracy values of apparent diffusion coefficient (ADC) with 0.6 as cutoff were sensitivity = 81.8%, specificity = 97.4%, positive predictive value = 90%, negative predictive value = 95%, and area under curve = 0.98 (95% confidence interval = 0.93–0.99) P = 0.0003. Thus, DWI using ADC with 0.6 as cutoff was found to be a very good diagnostic noninvasive tool. The diagnostic accuracy values of relative cerebral blood volume (rCBV) with 0.6 as cutoff were sensitivity = 90.5%, specificity = 98.7%, positive predictive value = 91.8%, and negative predictive value = 98.5%. Thus, DWI using rCBV with 2.52 as cutoff was found to be a very good diagnostic noninvasive tool. Conclusion: The ADC with cutoff of 0.6 and rCBV with cutoff value of 2.52 yield very good sensitivity, specificity, positive predictive value, and the negative predictive value as compared to histopathology. Hence, they can be used as noninvasive technique in differentiating Grade I meningioma from that of high-grade meningioma.