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Objective To explore the difference of pharmacokinetic parameters derived from dynamic contrast enhanced (DCE) MRI between primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM).Methods Data of 17 patients with PCNSL and 21 patients with GBM were retrospectively analyzed.All patients underwent DCE MRI.The pharmacokinetic parameters (K,Kep,Ve) and the initial (60 s) area under the Gd concentration-time curve (iAUC) of peri-tumoral parenchymas (PT),enhancement tumors (ET) and contralateral normal parenchyma (NP) were obtained.The differences of various parameters were compared among different regions of PCNSL and GBM using one-way ANOVA.The differences of various parameters of PT,ET and NP were compared using independent samples t-test.Results There were statistical differences of K,Kep in ET,Kep in PT between PCNSL and GBM patients (all P＜0.05),as well as of K,Kep,Ve,iAUC in PCNSL and GBM patients between ET and PT (all P＜0.05).However,K and Kepof PT showed statistical differences compared with those of NP in GBM patients (both P＜0.05),so did Ktrans between PT and NP in PCSL patients (P＜0.05).Conclusion The pharmacokinetic parameters derived from DCE MRI based on extended Tofts Linear can promote differential diagnosis between PCNSL and GBM.
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Objective To simulate the hemodynamic feature in cerebral bridging veins (BVs), in order to provide a morphologic basis for the pathogenesis explanation and imaging diagnosis of cerebral venous thrombosis (CVT). MethodsTotally 6 human cadavers (12 sides) were examined in this study. Each head of the cadavers was injected with blue-coloured latex via the superior sagittal sinus (SSS) and internal jugular veins. The diamter and the angle of BVs entering SSS were measured. Based on the data of cadavers and computational fluid dynamics software pack, the hemodynamic models were established. The wall shear stress (WSS) was carefully studied and compared between different models. Results The total of 137 BVs formed two clusters along the SSS: anterior group and posterior group. Compared with anterior group BVs, the diameter of posterior group BVs was large, and the angle was smaller. In 137 models,when the diameter of a BV was more than 1.2mm, and the angle was between 65 and 105 degree, the local WSS decreased in the downstream wall of SSS. When the diameter of a BV was more than 1.2mm, and the angle was less than 65 degree, the local WSS decreased in the downstream wall of SSS and the upstream wall of BVs. The minimum WSS in BVs was 63% of the minimum WSS in SSS. Compared with the anterior group BVs, the minimum WSS in the wall of posterior group BVs was samller, and the distance from the minimum WSS to the dural entrance was longer. Conclusion CVT occurs easily when the diamter of a BV is more than 1.2mm and the angle is less than 65 degree. The embolus forms early in the upstream wall of BVs entering the posterior part of SSS.
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Objective To further improve the morphological materials of AGs by micro-dissection, histology and CT, we observed the arachnoid granulations (AGs) in middle cranial fossa. Methods Thirty-three adult cadaveric heads were used for microsurgical dissection;Histological sections of AG specimens from 3 cadaver heads were examined. Forty patients who had both normal conventional brain CT and computed tomographic venography (CTV) were retrospectively reviewed. Results In middle cranial fossa the AGs occur in the following situations in order of frequency: the middle meningeal sinus, sphenoparietal sinus, lateral foramen rotundum and cavernous sinus. AGs usually show round, oval in shape and irregular in shape. AGs can be divided into individual type and leaflet type under light microscope. The numbers of AGs were observed by microanatomy and CTV were 8.72 and 3.52 respectively. The AGs of cavernous sinus was not localized precisely on CTV. Conclusion Study of the AGs in the middle cranial fossa systematically and comprehensively enriches anatomy and image knowledge. It is helpful in neurosurgical planning and choosing operalion procedure to avoid postoperative complications.