Combined Multiple Functional Magnetie Resonance Imaging(PWI FMRI DTI) In Brain Tunors Differential Diagnosis Pathological Grading And Pre-operative Planning

Objective:To investigate the applied value of perfusion weighted imaging(PWI)in diagnosing brain tumor;To observe the relationship between tumor and adjacent white matter fiber tracts and try to evaluate the combined use of fMRI and DTI in presurgical planning and surgical navigation. Methods:(1) Retrospectively collected17 cases of intracranial tumor patients, all patients were underwent conventional MRI, PWI and enhancement MRI examination before operation, and confirmed by postoperative pathology, including 12 cases of glioma and 5 cases of benign meningiomas.PWI data of all patients were analyzed, and maximum tumor perfusion area was defined in the regional cerebral blood volume(rCBV) mapping.A signal intensity-time curve was drawn.compared the charecteristics of various tumor perfusion curve, and calculated the maximum rCBV.the maximum relative regional cerebral blood volume was obtained by comparing with that in the normal contralateral white matter of brain as reference point.Compared the rrCBV in various tumor.(2) Retrospectively collected 18 cases of intracranial tumor patients, all patients were underwent conventional MRI, DTI and enhancement MRI examination before operation, with 10 cases underwent Blod-fMRI that tumor involving to motion coxtec. confirmed by postoperative pathology, including 13 cases of glioma and 5 cases of benign meningiomas. Deterministic tracking method was adopted to improve the reconstruction of fiber bundles and tumor area, analysis of DTT figure reflected general morphology change of the white matter fiber tracts near the tumor area, Combined fMRI and DTI can establish spatial relationships between eloquent white matter, motor functional area and the tumor borders. Result:(1) the maximum rrCBV of low and high grade glioma were1.73±0.62,2.93±0.39,there are statistically differences between them.High grade glioma was higher than low grade glioma in perfusion volume.(2) the perfusion of extra-axial tumor(meningioma)was significantly high in cerebral blood volume mapping, the contrast first pass signal intensity-time curve implying that the absence of boold-brain barrier contrast effused to the interstitial space from microcirculatory vessels.(3) Peritumoral regions of glioma changes of white matter fiber bundles was given priority to with destruction and infiltration; meningioma corresponding area changes of white matter fiber bundles was given priority to with pushing and shifting.(4) Combined fMRI and DTI can establish spatial relationships between eloquent white matter, motor area and the tumor borders, and provide a better estimation of the proximity of tumor borders to eloquent brain systems Conclusion:(1) Perfusion MR imaging can reveal the lesion vascular distribution and quantity angiogenensis of tumor. the maximum rCBV in tumor and peri-tumor is helpful and valuable for the grading of glioma and differentiating glioma from extra-axial.(2) DTT can reveal the tract white matter fiber tracts change.combined fMRI and DTI can provide information essential to preoperative planning, avoiding injury to the brain functional area and pyramidal tract.