Improved contrast agent bolus tracking using T1 FARM.

Current MRI bolus tracking techniques, such as saturation recovery Turbo-FLASH (srTFL), suffer from signal saturation at high contrast concentrations. In this study T1 Fast Acquisition Relaxation Mapping (T1 FARM) was compared to srTFL. In phantoms, T1 FARM maps were linear with [Gd-DTPA] up to 7.0 mmol/L while srTFL images saturated above 2.0 mmol/L. In the canine left ventricle, blood concentration curves determined from T1 FARM saturated with bolus injections exceeding 0.075 mmol/kg, while srTFL curves saturated above 0.025 mmol/kg of Gd-DTPA. Also, T1 FARM improved contrast-to-noise ratio in tissue concentration curves since higher contrast concentrations could be measured without saturating.     

Introducing navigated transcranial magnetic stimulation as a refined brain mapping methodology

A major intrinsic limitation of transcranial magnetic stimulation (TMS) to map the human brain lies in the unclear relationship between the position of the stimulating coil on the scalp and the underlying stimulated cortex. The relationship between structure and function as the major feature constituting a brain mapping modality can therefore not be established. Recent advances in image processing allowed us to refine TMS by combining magnetic resonance imaging (MRI) modalities with TMS using a neuronavigation system to measure the position of the stimulating coil and map this position onto a MRI data set. This technique has several advantages over recent TMS mapping strategies. The position of the coil on the scalp can be held constant as verified by real time visual guidance. When evaluating higher cortical functions, the relationship between underlying cortical anatomy and the scalp stimulation site can be accurately assessed. Cortical motor output maps can be easily obtained for preoperative planning and decision making for mass lesions near rolandic cortex in patients. In conclusion, navigated TMS is a reliable alternative for localizing cortical functions and therefore may be a useful adjunct or in selected patients even a helpful alternative to other functional neuroimaging methods. Electronic Publication     

Localization of the Sentinel Node of the Upper Outer Breast Quadrant in the Axillary Quadrants

Background

Sentinel node (SN) biopsy is associated with much less morbidity than axillary dissection. In patients with early breast cancer, lymphatic mapping and SN biopsy accurately stage the axillary nodes. Both currently available lymphatic mapping agents, radiocolloid and blue dye, have some limitations that may make perioperative or preoperative SN identification difficult. In such cases, exact knowledge of the topography of the axilla and the most probable location of the SN may be crucial.

Methods

In 12 fresh female cadavers with no history of breast carcinoma, injections of patent blue dye were used to visualize the SNs in the axillary quadrants and their lymphatic collectors from the upper outer quadrant of the breast, which is the most common location of breast cancer. The axilla was divided into quadrants with regard to the intersection of the thoracoepigastric vein and the third intercostobrachial nerve.

Results

All SNs were located within a circle of 2-cm radius of this intersection in the fatty tissue at the clavipectoral fascia. In most cases, the SN was located in the fatty tissue near the clavipectoral fascia in the lower ventral quadrant of the axilla (n = 14, 58%). In seven cases (29%), the SN was located in the upper ventral quadrant, in two cases (8%) in the upper dorsal quadrant, and in one case in the lower dorsal quadrant.

Conclusions

The results of this anatomical study may facilitate SN biopsy in patients with breast cancer.     

Mapping the Gastrointestinal Quality of Life Index to Short-Form 6D utility scores

Purpose

The Gastrointestinal Quality of Life Index (GIQLI) is a disease-specific quality of life instrument that is commonly used in gastrointestinal disorders. However, no preference weights, which are used to calculate quality-adjusted life years for cost-effectiveness analyses, for this instrument have been assigned. Therefore, the objective of this study was to develop a mapping function to derive utility scores for the GIQLI.

Methods

Patients undergoing elective laparoscopic cholecystectomy completed the short-form 6D (SF-6D), a preference-weighted utility measure, and the GIQLI at baseline and at 1 wk and 1 mo postoperatively. The responsiveness of the SF-6D to expected postoperative changes as well as the correlation between the SF-6D and the GIQLI was investigated. Ordinary least squares regression was performed to derive a mapping function using the baseline values, which was then validated using postoperative values. Adjusted r², mean absolute error, and root mean square error was used to determine model performance.

Results

A total of 50 patients were included in the study (mean age 51.1 [standard deviation 16.8], 28% male). The SF-6D and GIQLI domains were responsive to expected postoperative changes, and there was high correlation between the SF-6D and four of the five GIQLI domains (excluding treatment effects). The final mapping function explained 63% of the variance in the derivation sample but had relatively high mean absolute error (0.075 and 0.067 in the 1-wk and 1-mo samples, respectively) and adjusted root mean square error (13.1% and 12.0% in the 1-wk and 1-mo samples, respectively).

Conclusions

The GIQLI can be accurately mapped to SF-6D preference weights at the group level but may be too inexact at the individual level.     

Optimizing access and configuration of trauma centre care in New South Wales

IntroductionGetting the right patient, to the right place, at the right time is dependent on a multitude of modifiable and non-modifiable factors. One potentially modifiable factor is the number and location of trauma centres (TC). Overabundance of TC dilutes volumes and could be associated with worse outcomes. We describe a methodology that evaluates trauma system reconfiguration without reductions in potential access to care. We used the mature trauma system of New South Wales (NSW) as a model given the perceived overabundance of urban major trauma centres (MTC).MethodsWe first evaluated potential access to TC care via ground and air transport through the use of geographic information systems (GIS) network analysis. Potential access was defined as the proportion of the population living within 60-min transport time from a potential scene of injury to a TC by ground or rotary-wing aircraft. Sensitivity analyses were carried out in order to account for potential pre-hospital interventions and/or transport delays; travel times of 15-, 30-, 45-, 60-, and 90-min were also analyzed. We then evaluated if the current configuration of the system (number of urban MTS in the Sydney basin) could be optimized without reductions in potential access to care using two GIS methodologies: location-allocation and individual removal of MTC.Results86% of the NSW population has potential access to a TC within 60 min ground travel time; potential access improves to 99% with rotary-wing transport. The 1% of the population without potential TC access lives in 48% of the land area (>384,000km2). Utilizing two different methodologies we identified that there was no change in potential access by ground transport after removing 1 or 2 MTC in the Sydney basin at the 30-, 45-, and 60-min transport times. However, 0.02% and 0.5% of the population would not have potential access to MTC care at 15 min after removing one and two MTC respectively.DiscussionRedistribution of the number of MTC in the Sydney basin could be achieved without a significant impact on potential access to care. Our approach can be utilized as an initial tool to evaluate a trauma system where overabundance of coverage is present.     

1990—2014年徐州地区布加综合征空间分布特征和空间自相关分析研究

背景　布加综合征（BCS）是因肝静脉或下腔静脉流出道阻塞而导致各种症状的总称,流出道阻塞的范围可以是肝静脉到下腔静脉连接处之间,以及肝静脉到右心房之间的任何一处血管,目前中国BCS患者病因仍不明确。地理信息系统（GIS）是一门结合地图和地理空间分析方法的综合学科,不仅在地理学上有所应用,还广泛应用于疾病的空间分布研究。本研究首次应用GIS来描述徐州地区BCS患者空间分布情况及特征。目的　通过分析1990—2014年徐州地区BCS的空间分布特征及空间自相关关系,为BCS的病因研究和疾病防治提供参考依据。方法　收集1990—2014年徐州地区徐州医科大学附属医院、丰县人民医院、沛县人民医院、邳州市人民医院、新沂市人民医院、睢宁县人民医院的住院病历信息系统中所有首次确诊的BCS患者病历资料。汇总病例的人口信息,包括姓名、性别、年龄、家庭住址、住院日期、诊断等。每5年为1个时间段统计1990—2014年徐州地区BCS发病率;基于ArcGIS 10.4软件,采用全局空间自相关Moran's I指数分析和局部空间自相关Getis-Ord指数分析进行空间自相关分析。结果　1990—2014年,徐州市共有568例新发BCS患者。1990—2014年徐州地区BCS发病率逐年上升（由1990—1994年间的0.08/10万上升到2010—2014年间的0.35/10万）。对1990—2014年徐州地区BCS发病率以镇为单位进行全局空间自相关Moran's I指数分析,结果显示P值均>0.05,表明1990—2014年的各时间段BCS发病率空间分布自相关性均不显著（P>0.05）。局部空间自相关Getis-Ord指数分析结果显示,1990—1994年徐州地区BCS发病热点区域有徐州丰县、徐州市区东南部与睢宁县交界地区;1995—1999年徐州地区BCS发病热点区域为徐州市区与丰县、沛县交界地区,冷点地区为邳州市与睢宁县交界地区。2000—2004年徐州地区BCS发病热点区域为沛县微山湖周边,冷点区域为睢宁县南部;2005—2009年徐州地区BCS发病热点区域为沛县微山湖周围地区,冷点区域为徐州市区与丰县、沛县交界处;2010—2014年徐州地区BCS发病热点区域为徐州睢宁县东南部、沛县靠近微山湖地区、徐州市区,冷点区域在邳州市东部、新沂市、丰县。结论　1990—2014年各时间段徐州市BCS热点区域多为徐州市区及丰县、沛县、睢宁县以及微山湖周围受水污染的城镇,冷点区域为邳州市、新沂市;BCS热点区域多出现在重工业区和环境污染区,这提示环境污染以及重体力劳动可能是BCS发病的影响因素。     

基于联合点线特征的医疗服务机器人同时定位与地图构建算法研究

目的 为提高医疗服务机器人同时定位与地图构建（SLAM）算法全局定位精度和实时性,提出基于点线特征SLAM（PL-SLAM）算法,并与ORB（oriented FAST and rotated BRIEF）-SLAM2算法进行比较。方法 PL-SLAM算法在特征提取过程中在点特征的基础上增加线段特征,根据融合后的点线特征,在复杂医疗环境内进行地图创建与全局定位。利用公开数据集EuRoc和KITTI对比PL-SLAM算法与ORB-SLAM2算法,测试医疗服务机器人的自主导航综合性能。结果 与ORB-SLAM2算法相比,PL-SLAM算法在弱纹理环境下能够提取较多的点线特征,定位精度和实时性均有较大提升。其中旋转误差较ORB-SLAM2算法减小42.2%,运算速度提高55.9%。结论 PL-SLAM算法能够有效提高医疗服务机器人全局定位精度和实时性。     

病例教学联合思维导图在病理生理学教学中的应用

目的　评价病例教学联合思维导图在病理生理学教学中的应用效果,为提高病理生理学教学质量提供依据。方法　选取首都医科大学燕京医学院2017级本科生124名学生作为研究对象,分为试验组60人和对照组64人。其中,对照组采用传统教学,试验组采用课上病例教学联合课后思维导图的教学方式。课程结束后通过云班课平时成绩和试卷成绩对教学效果进行评价。采用SPSS 17.0进行Wilcoxon秩和检验和Welch’s correction t检验。结果　试验组学习的积极性得到了有效的调动（P<0.001）、知识的理解力也优于对照组（P=0.020）。试验组的平均理论成绩优于对照组（P=0.036）,主要表现为客观题成绩高于对照组（P<0.001）及简答和论述题成绩高于对照组（P=0.006）,名词解释成绩差异无统计学意义（P=0.302）。结论　病例教学联合思维导图可显著提高病理生理学的教学质量。     

Sentinel node mapping in high risk endometrial cancer after laparoscopic supracervical hysterectomy with morcellation

INTRODUCTIONOccult endometrial cancer after supracervical hysterectomy is very uncommon. Even if optimal management of those rare cases is still unproven, to guide the need for further therapies, restaging should be recommended in this situation.PRESENTATION OF CASEWe report of a 60-year old woman with occult high risk endometrial cancer after supracervical hysterectomy with morcellation. We describe the feasibility of laparoscopic intraoperative sentinel node identification with cervical stump removing to restage the suspicious early stage high risk endometrial cancer.DISCUSSIONIn high risk endometrial cancer surgical restaging is important, considering that 10–35% of cases can present pelvic nodal metastasis. To reduce the treatment related morbidity maintaining the benefit of surgical staging, with a negative preoperative PET/CT, we performed a laparoscopic SN mapping with cervical stump removing.CONCLUSIONThis report highlight the fact that SN mapping with cervical injection is a feasible and safe technique also without the uterine corpus after supracervical hysterectomy with morcellation.