The Study Of Mechanism On Arterial Spin Labeling And Conventional Contrast Agent In Glioma

ObjectiveGlioma is the most common intracranial tumors, the World Health Organization willbe divided into low-level(Ⅰ, Ⅱ), high-level(III, IV-class) tumors. Conventional magneticresonance could provide tumor size, border and its mass effect, but in the daily work, thereare some limitations in glioma grading and differential diagnosis of benign malignant bythese features alone. Arterial spin labeling (Arterial Spin Labeling, ASL) is an in vivonon-invasive detection of cerebral hemodynamics new magnetic resonance imagingmethod, you can get the region of interest blood flow, blood volume and other parameters.To explore the research value and clinical significance of Arterial Spin Labeling (ASL) indifferential diagnosis of high and low grade intracranial tumor. The purpose of this study isto investigate the arterial spin labeling intracranial tumor (low, high level) of gliomasenhanced mechanism research value and clinical significances.MethodsCollected from January2011to January2013, the Department of Neurology of ourhospital ward or preliminary diagnosis of intracranial tumor and underwent surgery,39patients with postoperative glioma patients with pathologically confirmed30cases, and theremaining nine cases not as a result of the study, according to the World HealthOrganization rule of the central nervous system tumor classification criteria,30patientswith glioma in the low-level group of12patients, including four cases of class I, eightcases for class II, high-level group of18patients, including twelve cases for class III, sixcases for class IV. With the consent of the patients and their families, all patients underwentpreoperative conventional MRI scan, ASL and enhanced scan, we could obtain the rCBFdiagram by the ASL raw data collected with reformat software. By integration with ASL andFLAIR, select the solid part of the tumor perfusion level as analysis level，and the most obvioustumor solid perfusion area as region of interest，obtain the maximal tumor blood flow，to compute the ratio of the maximal tumor blood flow and normal white matter, gray matter,hemisphere region offside, that is relative cerebral blood flow for tumor. Statisticallyanalyzed using the SPSS17.0software. By two attending physician class doctors read theimages at the same time the initial diagnosis of pathological, Firstly by conventional plaincombined with enhanced scan sequence to make the diagnosis of pathological grades, Thencombination of the ASL sequence of the resulting image again to make the diagnosis ofpathological grades, Finally, compared with pathological results, compare the two methodsbefore and after the diagnosis rate.ResultsIn ASL perfusion image, part of the high grade glioma showed obviously high perfusion, low grade glioma showed low blood perfusion, the ratio of the maximal tumor bloodflow and normal white matter, gray matter, hemisphere region offside were2.13±1.01,0.72±0.05;1.21±0.13,0.98±0.1;1.73±0.67,0.95±0.06respectively;high and low grade tumorcerebral blood flow was obvious differences.Part of high grade tumor essence was-seen abnormal strengthening lesion, low grade tumors were significant with eudative enhanced lesson. Relative performance in tumor blood flow value compared with pathological results, itwas found that physicians only by conventional and enhanced on MR scan imagemisdiagnosis rate of pathological results in low-grade tumors, there is a significantdifference (p<0.05);20%, after scanning in ASL misdiagnosis rate was13%, twicediagnosis is not a statistically significant difference, but scanning in ASL to some extent,reduce the rate of misdiagnosis of diagnosis. Relative tumor blood flow was significantdifferent in high and low grade tumor.ConclusionPerfusion of the ASL technology can be non invasive to understand intracranialtumors gliomas of different grades and its blood supply around, to help their preoperativegrading and better assess the effect of cancer chemotherapy.