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Misung Han Baolian Yang Brice Fernandez Marisa Lafontaine Paula Alcaide‐Leon Angela Jakary Brian L. Burns Melanie A. Morrison Javier E. Villanueva‐Meyer Susan M. Chang Suchandrima Banerjee Janine M. Lupo 《NMR in biomedicine》2021,34(1)
Although combined spin‐ and gradient‐echo (SAGE) dynamic susceptibility‐contrast (DSC) MRI can provide perfusion quantification that is sensitive to both macrovessels and microvessels while correcting for T1‐shortening effects, spatial coverage is often limited in order to maintain a high temporal resolution for DSC quantification. In this work, we combined a SAGE echo‐planar imaging (EPI) sequence with simultaneous multi‐slice (SMS) excitation and blipped controlled aliasing in parallel imaging (blipped CAIPI) at 3 T to achieve both high temporal resolution and whole brain coverage. Two protocols using this sequence with multi‐band (MB) acceleration factors of 2 and 3 were evaluated in 20 patients with treated gliomas to determine the optimal scan parameters for clinical use. ΔR2*(t) and ΔR2(t) curves were derived to calculate dynamic signal‐to‐noise ratio (dSNR), ΔR2*‐ and ΔR2‐based relative cerebral blood volume (rCBV), and mean vessel diameter (mVD) for each voxel. The resulting SAGE DSC images acquired using MB acceleration of 3 versus 2 appeared visually similar in terms of image distortion and contrast. The difference in the mean dSNR from normal‐appearing white matter (NAWM) and that in the mean dSNR between NAWM and normal‐appearing gray matter were not statistically significant between the two protocols. ΔR2*‐ and ΔR2‐rCBV maps and mVD maps provided unique contrast and spatial heterogeneity within tumors. 相似文献
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Brian N. Arnold Daniel C. Thomas Vikrant Bhatnagar Justin D. Blasberg Zuoheng Wang Daniel J. Boffa Frank C. Detterbeck Anthony W. Kim 《Surgery》2019,165(2):450-454
Background
Robot-assisted thoracoscopic lobectomy has been shown to be a safe approach to pulmonary lobectomy. This study sought to define, mathematically, the learning curve for RATS lobectomy.Methods
Patients undergoing robot-assisted thoracoscopic lobectomy at a single institution from 2010 through 2016 were considered. Covariates included patient demographics, comorbidities, operating time, length of stay, estimated blood loss, and postoperative complications. A cumulative sum analysis of operating time was performed to define the learning curve.Results
A total of 101 patients were included. Three distinct phases of the learning curve were identified: cases 1–22, cases 23–63, and cases 64–101. There was a statistically significant difference in operating time and estimated blood loss between phases 1 and 2 (P < .05, P?=?.016, respectively) and between phases 1 and 3 (P < .05, P?=?.006, respectively). There was no statistically significant difference in comorbidities, chest tube duration, length of stay, postoperative complications, or conversion rate across the learning curve.Conclusion
Based on operating time, the learning curve for robot-assisted thoracoscopic lobectomy is 22 cases, with mastery achieved after 63 cases. No differences in length of stay, chest tube duration, conversion rate, or complication rate were observed in the learning curve. Other factors not measured in this study may play a role in the learning process and warrant further study. 相似文献30.
Weifeng Tang Helena Engman Yali Zhu Brian Dayton David W. Boulton 《Clinical therapeutics》2019,41(8):1545-1563
PurposeFixed-combination drug products (FCDPs) for patients with type 2 diabetes mellitus (T2DM) may show efficacy comparable to their individual components (ICs) while improving adherence to treatment. This study evaluated the bioequivalence and safety of 2 dapagliflozin/saxagliptin/metformin extended-release (XR) FCDPs relative to their ICs: saxagliptin and dapagliflozin/metformin XR.MethodsThis randomized, open-label, single-dose, single-center crossover study was conducted in 84 healthy subjects aged 18–55 years. The primary objective was to evaluate the fed-state bioequivalence of a dapagliflozin 5-mg/saxagliptin 2.5-mg/metformin 1000-mg XR FCDP and a dapagliflozin 10-mg/saxagliptin 5-mg/metformin 1000-mg XR FCDP relative to the ICs. Secondary objectives included the evaluation of the effect of food on the pharmacokinetic (PK) parameters of saxagliptin, dapagliflozin, and metformin in both FCDPs and characterization of the PK parameters of the active metabolite of saxagliptin, 5-hydroxy saxagliptin, in healthy subjects. PK parameters (AUC0–∞, AUC0–t, and Cmax) were used to assess the bioequivalence of the 2 FCDPs with their ICs. The Cmax and AUC0–t of the study drugs were compared between female and male subjects to assess sex differences in exposure. Safety and tolerability of both FCDPs and ICs were also assessed with adverse events, vital signs (systolic and diastolic blood pressures and pulse rate), 12-lead ECG, physical examinations, and laboratory assessments.FindingsBoth dapagliflozin/saxagliptin/metformin XR FCDPs were bioequivalent to their ICs. For the dapagliflozin 5-mg/saxagliptin 2.5-mg/metformin 1000-mg XR FCDP, the 90% CI for the geometric mean ratio of dapagliflozin Cmax was slightly above the 80%–125% bioequivalence limit, which is unlikely to be clinically relevant. Food delayed the absorption of the study drugs in both FCDPs, which is unlikely to have a clinically relevant impact on efficacy. In both cohorts, exposure was higher in female subjects compared with male subjects, potentially due to the lower body weight of the female subjects. The safety profile and tolerability of the FCDPs were similar to those of their ICs, and no deaths or serious adverse events were reported.ImplicationsThese data support the use of the dapagliflozin/saxagliptin/metformin XR FCDP in patients with T2DM. ClinicalTrials.gov identifier: NCT03169959. 相似文献