Arterial spin labeling MR image denoising and reconstruction using unsupervised deep learning

Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging.     

Particularidades del abordaje transcanal endoscópico de los tumores benignos de oído medio en adultos

Background and objectiveMinimally invasive surgery of benign middle ear tumours is possible by using the endoscope. The optimal lighting and the broadest vision it offers, allow a transcanal approach to these rare tumours. The objective of this work is to summarize its key points through a case series.Materials and methodsRetrospective study of benign middle ear tumours that underwent exclusive endoscopic surgery in a third-level adult university hospital between June 2018 and June 2020. Postoperative follow-up was performed by otoendoscopy and audiometry.ResultsSix patients underwent surgery during the study period. Five patients were female and one male, with an average age of 57.8 years (± 21.9). Four tumours were in the left ear and 2 in the right ear. These included 4 tympanic paragangliomas (3 type I and one type II), a chorda tympani neuroma, and a congenital cholesteatoma. There were no serious postoperative complications. At present, no tumour recurrence has been found in either case, with a minimum follow-up of 7 months.ConclusionsThe present study adds evidence on the safety and efficacy of endoscopic transcanal ear surgery, as a minimally invasive technique, for the treatment of benign middle ear tumours confined to the tympanic cavity.     

Differing Characteristics of Human-Shaped Visual Stimuli Affect Clinicians’ Dosage of a Spinal Manipulative Thrust on a Low-Fidelity Model: A Cross-Sectional Study

ObjectiveThe purpose of this study was to determine whether chiropractic clinicians modulate spinal manipulation (SM) thrust characteristics based on visual perception of simulated human silhouette attributes.MethodsWe performed a cross-sectional within-participant design with 8 experienced chiropractors. During each trial, participants observed a human-shaped life-sized silhouette of a mock patient and delivered an SM thrust on a low-fidelity thoracic spine model based on their visual perception. Silhouettes varied on the following 3 factors: apparent sex (male or female silhouette), height (short, average, tall), and body mass index (BMI) (underweight, healthy, obese). Each combination was presented 6 times for a total of 108 trials in random order. Outcome measures included peak thrust force, thrust duration, peak preload force, peak acceleration, time to peak acceleration, and rate of force application. A 3-way repeated measures analysis of variance model was used to for each variable, followed by Tukey's honestly significant difference on significant interactions.ResultsPeak thrust force was reduced when apparent sex of the presented silhouette was female (F_1,7 = 5.70, P = .048). Thrust duration was largely invariant, except that a BMI by height interaction revealed a longer duration occurred for healthy tall participants than healthy short participants (F_4,28 = 4.34, P = .007). Compared to an image depicting obese BMI, an image appearing underweight lead to reduced peak acceleration (F_2,5 = 6.756, P = .009). Clinician time to peak acceleration was reduced in short compared to tall silhouettes (t₇ = 2.20, P = .032).ConclusionVisual perception of simulated human silhouette attributes, including apparent sex, height, and BMI, influenced SM dose characteristics through both kinetic and kinematic measures. The results suggest that visual information from mock patients affects the decision-making of chiropractic clinicians delivering SM thrusts.     

Occurrence,detection and ecotoxicity studies of selected pharmaceuticals in aqueous ecosystems- a systematic appraisal

Pharmaceutical compounds (PCs) have globally emerged as a significant group of environmental contaminants due to the constant detection of their residues in the environment. The main scope of this review is to fill the void of information on the knowledge on the African occurrence of selected PCs in environmental matrices in comparison with those outside Africa and their respective toxic actions on both aquatic and non-aquatic biota through ecotoxicity bioassays. To achieve this objective, the study focused on commonly used and detected pharmaceutical drugs (residues). Based on the conducted literature survey, Africa has the highest levels of ciprofloxacin, sulfamethoxazole, lamivudine, acetaminophen, and diclofenac while Europe has the lowest of all these PC residues in her physical environments. For ecotoxicity bioassays, the few data available are mostly on individual groups of pharmaceuticals whereas there is sparsely available data on their combined forms.     

Differences in Evidentiary Requirements Between European Medicines Agency and European Health Technology Assessment of Oncology Drugs—Can Alignment Be Enhanced?

ObjectivesNational health technology assessments (HTAs) across Europe show differences in evidentiary requirements from assessments by the European Medicines Agency (EMA), affecting time to patient access for drugs after marketing authorization. This article analyzes the differences between EMA and HTA bodies’ evidentiary requirements for oncology drugs and provides recommendations on potential further alignment to minimize and optimally manage the remaining differences.MethodsInterviews were performed with representatives and drug assessment experts from EMA and HTA bodies to identify evidentiary requirements for several subdomains and collect recommendations for potentially more efficiently addressing differences. A comparative analysis of acceptability of the evidence by EMA and the HTA bodies and for potential further alignment between both authorities was conducted.ResultsAcceptability of available evidence was higher for EMA than HTA bodies. HTA bodies and EMA were aligned on evidentiary requirements in most cases. The subdomains showing notable differences concerned the acceptance of limitation of the target population and extrapolation of target populations, progression-free survival and (other) surrogate endpoints as outcomes, cross-over designs, short trial duration, and clinical relevance of the effect size. Recommendations for reducing or optimally managing differences included joint early dialogues, joint relative effectiveness assessments, and the use of managed entry agreements.ConclusionsDifferences between assessments of EMA and HTA bodies were identified in important areas of evidentiary requirements. Increased alignment between EMA and HTA bodies is suggested and recommendations for realization are discussed.     

F形空心钉与传统3枚平行钉治疗Pauwels Ⅲ型股骨颈骨折的疗效比较

目的:分析比较"F"形空心钉与传统倒三角3枚平行螺钉内固定治疗青壮年Pauwels Ⅲ型股骨颈骨折的临床疗效。方法：2017年1月至2020年1月收治Pauwels Ⅲ型股骨颈骨折患者38例，根据置入钉方式的不同将其分为两组，其中A组18例，采用"F"形空心钉固定，男12例，女6例，年龄37~55岁，受伤至手术时间1~3 d。B组20例，采用传统倒三角3枚平行拉力螺钉固定，男12例，女8例，年龄35~55岁，受伤至手术时间为1~3 d。比较两组患者骨折不愈合，股骨头坏死，股骨颈短缩，空心螺钉退出情况，髋关节功能Harris评分，疼痛视觉模拟评分（visual analogue scale，VAS）。结果：所有患者获得随访，时间为15~31个月。两组患者在骨折不愈合，股骨颈短缩，股骨头坏死方面差异无统计学意义（P>0.05）；两组患者在螺钉退出方面差异有统计学意义（P<0.05）。两组患者术后12个月时髋关节Harris评分及VAS评分差异均无统计学差异（P>0.05）。结论："F"形与传统倒三角3枚平行空心钉内固定治疗青壮年Pauwels Ⅲ型股骨颈骨折中短期疗效相似，但"F"形空心钉退钉率较低。     

改良眶隔法和传统睑板法切开重睑术的术后重睑形态、瘢痕发生率、角膜暴露率比较研究

目的 比较改良眶隔法和传统睑板法切开重睑术中的应用效果及对术后重睑形态、瘢痕发生率、角膜暴露率的影响。方法 选取2020年3月-2021年3月首都医疗爱育华医院收治的80例单睑患者，采用随机数字表法将其分对照组和观察组，各40例。对照组接受传统睑板法切开重睑术，观察组接受改良眶隔法切开重睑术，比较两组术后重睑形态、瘢痕发生率、角膜暴露率、并发症发生率。结果 观察组总有效率高于对照组，差异有统计学意义（P＜0.05）；观察组GAIS评分高于对照组，VAS评分低于对照组，差异有统计学意义（P＜0.05）；观察组右侧角膜暴露率增加值、左侧角膜暴露率增加值高于对照组，差异有统计学意义（P＜0.05）；观察组并发症发生率为5.00%，低于对照组的22.50%，差异有统计学意义（P＜0.05）。结论 相比于传统睑板法切开重睑术，改良眶隔法切开重睑术不会过度增加术后角膜暴露率，术后瘢痕发生率更低，重睑形态更理想，患者接受度更高。