Introduction Our purpose was to determine whether perfusion MR imaging can be used to differentiate benign and malignant meningiomas on the basis of the differences in perfusion of tumor parenchyma and/or peritumoral edema. Methods A total of 33 patients with preoperative meningiomas (25 benign and 8 malignant) underwent conventional and dynamic susceptibility contrast perfusion MR imaging. Maximal relative cerebral blood volume (rCBV) and the corresponding relative mean time to enhance (rMTE) (relative to the contralateral normal white matter) in both tumor parenchyma and peritumoral edema were measured. The independent samples t-test was used to determine whether there was a statistically significant difference in the mean rCBV and rMTE ratios between benign and malignant meningiomas. Results The mean maximal rCBV values of benign and malignant meningiomas were 7.16±4.08 (mean±SD) and 5.89±3.86, respectively, in the parenchyma, and 1.05±0.96 and 3.82±1.39, respectively, in the peritumoral edema. The mean rMTE values were 1.16±0.24 and 1.30±0.32, respectively, in the parenchyma, and 0.91±0.25 and 1.24±0.35, respectively, in the peritumoral edema. The differences in rCBV and rMTE values between benign and malignant meningiomas were not statistically significant (P>0.05) in the parenchyma, but both were statistically significant (P<0.05) in the peritumoral edema. Conclusion Perfusion MR imaging can provide useful information on meningioma vascularity which is not available from conventional MRI. Measurement of maximal rCBV and corresponding rMTE values in the peritumoral edema is useful in the preoperative differentiation between benign and malignant meningiomas.

Clinical trial registration: NCT01058746 Objective To examine, by a prospective randomized controlled trial, the influence of Liberal (LIB) versus Restricted (RES) perioperative fluid administration on morbidity following pancreatectomy. Summary Background Data Randomized controlled trials in patients undergoing major intra-abdominal surgery have challenged the historical use of liberal fluid administration, suggesting a more restricted regimen may be associated with fewer postoperative complications. Methods Patients scheduled to undergo pancreatic resection were consented for randomization to a LIB (n=164) or RES (n=166) perioperative fluid regimen. Sample size was designed with 80% power to decrease Grade 3 complications from 35% to 21%. Results Between July 2009 and July 2015, we randomized 330 patients undergoing pancreaticoduodenectomy (PD, n=218), central (n=16) or distal pancreatectomy (DP, n=96). Patients were equally distributed for all demographic and intraoperative characteristics. Intraoperatively, LIB patients received crystalloid 12ml/kg/hr and RES patients 6ml/kg/hr. Cumulative crystalloid given (median, range, ml) days 0–3 was LIB: 12252 (6600–21365), RES 7808 (2700–16274) p<0.0001. Sixty day mortality was 2/330 (0.6%). Median operative time for PD was 227 minutes (105–462) and DP 150 (44–323). Grade 3 complications occurred in 20% of LIB and 27% of RES patients (p=0.6). Median length of stay was 7 days and 5 days for PD and DP, respectively, in both arms. Conclusions In a high volume institution, major perioperative complications from pancreatic resection were not significantly influenced by fluid regimens that differed approximately 1.6 fold.