The Control Study Of MR Diffusion Weight Imaging And Perfusion Weighted Imaging Of Cerebral Gliomas And Its Histology

PrefacePresurgical determination of malignancy and prognosis of cerebral gliomas play important roles in clinical work due to different methods of treatment. Routine MR imaging is difficult to provide functional information such as pathological grading, angiogenesis, and biochemical information though it may be useful for morphological diagnosis of gliomas. Diffusion weighted imaging ( DWI) allows us to observe the microcosmic movement of the water molecules in the living tissues; dynamic contrast - enhanced perfusion imaging (PWI) can evaluate the cerebral hemodynamic status noninvasively, which is developing with the presence of fast MR imaging technique. Both of the two methods, as complementary methods for routine MR examination, may give us more functional information in the diagnosis of gliomas, and provide the objective criterion for the early diagnosis and prognostic assessment.Our studies introduce leading theory of tumorigenesis into territory of imaging study, improve present methods of imaging study, break through traditional imaging study theory and engage in the study of microcirculation and cerebral metabolites noninvasively. For the first time, we combine MR functional techniques to study the biological characteristics of cerebral gliomas, correlated with histopathology in order to improve the early diagnostic cerebral gliomas.Purpose ?DWI, PWI, study of biological characteristics of gliomas in brain was performed to evaluate two methods in the determination of pathological grading, microcirculation of the tumor, and to establish internal connection between DWI/ PWI and histology/microvessel counting.Materials and Methods23 patients were used for this study. The brain of each patient was imaged with precontrast T1 weighted spin - echo imaging (T1 WI) , T2 weighted spin -echo imaging(T2WI) , diffusion weighted imaging (DWI) , perfusion weighted imaging ( PWI) , and postcontrast T1 WI. After the brains were operated, they were examined histologically using both hematoxylin and eosin (HE) and immu-nohistochemical staining for CD34 to mark endothelial cells. Tumor cellularity in each specimen was analyzed under light microscope ( original magnification 200) ; microvascular density ( MVD ) was counted in histological sections stained with CD34. Separate statistical comparisons of the tumor cellularity with the ADC values of tumoural region, and MVD with maximal rCBV values were made using simple linear regression analysis, and a P value of less than 0. 05 was considered to indicate statistical significance.ResultsOn DWIs, the signal intensity in the solid portion of the tumor was hyperin-tense with respect to the contralateral white matter. Statistical discrepancies of the ADC values for both the solid tumor component and peritumoral region were present comparing high - grade glioma with low - grade glioma with contralateral white matter respectively (P <0.01). The ADC value for the solid tumor component was decreased with the increase of tumor cellularity, negatively correlated with tumor cellularity (r= -0.84,P <0.01).