A Preliminary Study of Dynamic Susceptibility Contrast-Enhanced Perfusion Findings in Primary Intracranial Lymphoma

Objective To study dynamic susceptibility contrast-enhanced(DSC) perfusion-weighted imaging features of primary intracranial lymphomas.Materials and Methods DSC perfusion-weighted imaging scans were performed by echoplanar imaging(EPI).The rCBV map,rCBF map,MTT map and intensity-time curve were obtained,and the maximum rCBV ratio and MTT ratio of tumor parenchyma were calculated in 9 cases of intracranial lymphomas.DSC perfusion-weighted imaging features and histological results of 9 intracranial lymphomas were compared with 14 cases of high grade(Ⅲ、Ⅳ) astrocytomas.Results The maximum rCBV ratio of primary intracranial lymphomas was 1.71±0.59,while that of high grade astrocytomas was 5.17±1.73.The primary intracranial lymphoma had a tendency to have relatively low perfusion compared with high grade astrocytomas(P0.001).The differences of MTT ratio between primary intracranial lymphomas and high grade astrocytomas showed no statistical significance(P=0.101)in tumor parenchyma.The intensity-time curve of primary intracranial lymphomas exceeded the baseline after first-pass,while the intensity-time curve of high grade astrocytomas never exceeded the baseline after first-pass,and a little decrease wave was identified before curve reach the baseline.The primary intracranial lymphomas showed a hypercellular neoplasm,and the tumor cells infiltrating round the vessels were identified while the formation of tumor neovascularization is absent.The high grade astrocytomas showed abundant tumor neovascularization.Conclusion Primary intracranial lymphomas have relatively low rCBV values.The different manifestations between rimary intracranial lymphomas and high grade astrocytomas,such as the maximum rCBV ratio of primary intracranial lymphomas is lower than that of high grade astrocytomas and the intensity-time curve of primary intracranial lymphomas is different from that of high grade astrocytomas,is determined by their different histopathological characterisic.DSC perfusion-weighted imaging can improved MRI diagnostic accuracy of primary intracranial lymphoma.