扩散张量成像各向异性分数在足月新生儿缺氧缺血性脑病中的应用

目的探讨磁共振扩散张量成像(DTI)的各向异性分数(FA)值在足月新生儿缺氧缺血性脑病(HIE)早期诊断及病情评估中的应用,为临床治疗提供依据。资料与方法收集58例临床确诊的足月HIE患儿,其中轻度HIE 28例,中度HIE19例,重度HIE 11例,并选取20例正常足月新生儿为对照组,行颅脑常规MRI及DTI扫描,测量内囊前肢、内囊后肢、豆状核、胼胝体膝部及胼胝体压部的FA值,比较各组不同部位的FA值。结果对照组内囊前后肢、胼胝体膝部和压部的FA值均高于中度HIE组和重度HIE组,对照组胼胝体膝部的FA值高于轻度HIE组,轻度HIE组和中度HIE组内囊前后肢、胼胝体膝部和压部的FA值高于重度HIE组,轻度HIE组内囊后肢FA值高于中度HIE组,差异均有统计学意义(P<0.05);各组豆状核的FA值差异均无统计学意义(P>0.05)。在各部位中,内囊后肢FA值诊断HIE的准确度最高,曲线下面积为0.802,当内囊后肢FA值的截断点取0.543时,诊断灵敏度为61.2%,特异度为85.0%,Youden指数为0.462。结论 DTI FA值可以早期、定量评价HIE新生儿脑损伤的程度,为HIE的早期诊断及病情评估提供客观依据。     

DTI在PVL合并脑瘫患儿术后脑白质恢复中的应用价值

目的 探讨扩散张量成像(DTI)技术在脑室周围白质软化症(PVL)合并脑瘫患儿术后脑白质恢复中的应用价值.方法 收集经临床诊断为PVL合并脑瘫患儿15例作为病例组,另选相匹配的正常儿童志愿者15例作为对照组,均进行常规MRI平扫及DTI检查,并获得各向异性分数(FA)图,测量病例组治疗前后与对照组皮质脊髓束(内囊膝、内囊后肢、大脑脚及脑桥水平)、基底节区核团(尾状核、豆状核)感兴趣区的FA值差异.结果 双侧内囊膝、内囊后肢、脑桥、胼胝体压部、膝部及双侧大脑脚的FA值在病例组治疗前、后(术后1个月)与对照组间有统计学差异(P＜0.05),3组豆状核、尾状核的FA值无统计学意义.进一步两两比较,双侧内囊后肢、胼胝体压部、膝部任意2组间比较均有统计学差异,双侧内囊膝、脑桥、双侧大脑脚治疗前、后无统计学意义,双侧内囊膝、脑桥、双侧大脑脚治疗前与对照组间比较均有统计学意义(P＜0.05).结论 DTI技术可显示脑白质细微结构变化,其FA值在PVL合并脑瘫患儿术后脑白质恢复中有一定参考价值,有助于指导临床医生进一步合理治疗.     

磁共振弥散张量成像联合弥散张量纤维束成像在早期弥漫性轴索损伤中的应用

目的探讨磁共振弥散张量成像(DTI)与弥散张量纤维束示踪技术(DTT)对早期弥漫性轴索损伤(DAI)的诊断应用价值。方法对22例DAI早期(伤后10天内)患者(DAI组)及12例正常志愿者(对照组)分别行常规MR扫描及弥散张量成像扫描。在FA图上分别测量DAI组及对照组双侧半球白质感兴趣区(胼胝体压部、胼胝体膝部、内囊前肢、内囊后肢)部分各向异性(FA)值,将两组感兴趣区(ROI)平均FA值的差异进行比较,并对DAI组FA值与临床GCS评分进行相关性分析。运用弥散张量纤维束成像显示通过病灶的纤维束特征。结果病变组与对照组比较,DAI早期FA值(胼胝体压部0.647±0.069、胼胝体膝部0.615±0.043、内囊前肢0.541±0.065、内囊后肢0.639±0.035)较对照组(胼胝体压部0.748±0.045、胼胝体膝部0.729±0.058、内囊前肢0.622±0.038、内囊后肢0.667±0.027)FA值显著降低(P0.001)。胼胝体压部FA值的变化与GCS评分呈正相关(r=0.736,P=0.001)。DTT较好显示感兴趣区白质纤维束形态,更直观显示脑白质损伤程度。结论 DTI联合DTT是DAI患者检查的敏感方法,FA值评估是DAI程度的重要依据,DDT可观察神经纤维束受损范围。     

正常儿童脑白质发育的DTI研究

目的 :用DTI研究正常儿童脑白质发育特点。方法 :收集50例1~12岁健康儿童脑DTI图像,分析第1组(1~3岁)、第2组(4~6岁)、第3组(7~9岁)及第4组(10~12岁)4个年龄组与脑白质内囊前肢、内囊后肢、胼胝体膝部、胼胝体压部及尾状核头部5个部位的各向异性指数(FA)值、ADC值的相关性及差异性。结果:内囊前肢、内囊后肢、胼胝体膝部及胼胝体压部的FA值与年龄呈正相关,尾状核头部的FA值与年龄呈负相关;内囊前肢、内囊后肢、胼胝体膝部、胼胝体压部及尾状核头部的ADC值均与年龄呈负相关。第1、2组间及第2、3组间内囊前肢、内囊后肢、胼胝体膝部及胼胝体压部的FA值、ADC值差异均有统计学意义(均P0.05);第3、4组组间胼胝体膝部及胼胝体压部的FA值、ADC值差异均有统计学意义(均P0.05)。结论:DTI的FA值和ADC值能反映脑白质发育差异。     

青壮年颞叶癫痫患者颞叶外脑结构的DTI研究

目的利用扩散张量成像技术观察青壮年颞叶癫痫(TLE)患者颞叶外不同脑结构的DTI测值,观察其扩散功能的改变。方法采用GE公司3.0T磁共振检查了20例青壮年颞叶癫痫患者及20例与之匹配的健康对照组,选择双侧内囊前肢(AIC)、后肢(PIC)、外囊(EC)、尾状核头(HCN)、豆状核(LN)、丘脑(TL)及胼胝体膝部(GCC)、体部(BCC)、压部(SCC)为感兴趣区(ROI),评价指标为FA、ADC、λ∥及λ⊥。结果与对照组相比,TLE患者所有ROI的FA值均降低,双侧EC、HCN、TL及BCC的ADC值升高,患侧LN和双侧AIC、TL、GCC的λ∥降低,所有ROI的λ⊥均升高(仅双侧PIC的λ⊥未见明显差异)。TLE组患侧与对侧相比,患侧HCN的FA值较对侧减低。Pearson相关分析发现患者GCC的ADC值与发病年龄呈负相关,与病程呈正相关;患者GCC的λ⊥与病程呈正相关;患侧PIC的λ∥与发病年龄呈负相关,对侧AIC的λ⊥与病程呈负相关。结论 TLE患者可产生较广泛的大脑双侧半球的灰白质结构的异常;患者发病年龄越小、病程越长其胼胝体及内囊所受的影响就越严重。     

颞叶癫痫患者的颞叶以外白质MR扩散张量成像研究

目的 应用MR扩散张量成像(DTI)探讨颞叶癫痫(TLE)患者的颞叶以外白质是否存在隐匿性损伤,并研究这些白质结构的DTI参数值与患者初次发病年龄及病程长短的相关性.资料与方法 对临床确诊的42例发作间期TLE患者和32名健康志愿者行常规MRI和DTI检查,定量测量胼胝体膝部、体部、压部、内囊前肢、后肢及外囊的平均扩散系数(Dcavg)和部分各向异性(FA)值并进行统计学分析.结果 TLE患者胼胝体压部、内囊后肢及外囊的Dcavg值显著高于正常人(P<0.01),胼胝体膝部、压部、内囊前肢及外囊的FA值显著低于正常人(P<0.05).TLE患者内囊后肢Dcavg值与病程长短呈正相关.结论 TLE患者的颞叶以外白质存在隐匿性损伤,内囊后肢的损伤程度与病程长短有关.     

DTI评价不同期HIV相关性痴呆脑白质微细结构损害

目的:应用磁共振扩散张量成像(DTI)技术研究不同期HIV相关性痴呆(HAD)患者脑白质微细结构的改变.方法:对17例HAD患者(中重度组9例,亚临床组8例)及10例年龄性别相匹配的健康对照组行常规MRI及DTI检查,测量其额叶、顶叶、颞叶、枕叶、胼胝体膝部、压部、内囊前、后肢白质区部分各向异性分数(FA)和表观扩散系...     

扩散张量成像在新生儿缺氧缺血性脑病中的应用

目的 探讨扩散张量成像(DTI)在新生儿缺氧缺血性脑病(HIE)中的应用价值.方法 选取确诊为HIE的足月新生儿37例,正常足月新生儿12 例,应用3.0T磁共振仪对所有研究对象均行常规MRI序列和DTI序列扫描.采用单因素方差分析方法,对HIE组与正常组新生儿头颅感兴趣区(ROI)测得各向异性分数(FA)值进行统计学分析.内囊后肢FA值与新生儿神经行为测定(NBNA)评分采用线性分析,计算相关度.结果 内囊后肢、胼胝体压部的FA值在HIE轻度组、中度组、重度组与对照组比较差异有统计学意义(P<0.05);额叶中央白质、丘脑的FA值在HIE重度组与对照组比较差异有统计学意义(P<0.05);豆状核的FA值与对照组比较差异无统计学意义(P>0.05).内囊后肢FA值与NBNA评分(12~14 d;26~28 d)呈明显相关性(r=0.96,P<0.05;r=0.87,P<0.05).结论 DTI技术可对早期HIE脑损伤进行评价,并在预后评价方面中有重要应用价值.     

磁共振弥散张量成像在弥漫性轴索损伤中的研究价值

目的 探讨磁共振弥散张量成像(DTI)在弥漫性轴索损伤(DAI)中的研究价值.方法 DAI组急性期26例,其中9例为复查病例(慢性期),对照组20例,常规磁共振检查后,行DTI扫描,分别测量DAI急性期及慢性期和对照组各感兴趣区部分各向异性(FA)值,将2组间相应感兴趣区的FA值进行对比,并对急性期FA值与格拉斯哥昏迷计分表(GCS)评分进行相关性分析.结果 DAI急性期FA值(胼胝体压部0.560±0.004,胼胝体膝部0.467±0.004,内囊后 肢0.598±0.012,半卵圆中心0.434±0.002)与对照组(胼胝体压部0.756±0.006,胼胝体膝部0.542±0.007,内囊后肢0.639±0.009,半卵圆中心0.480±0.003)有差异,胼胝体压部FA值与GCS评分有较好的相关性(r=0.693,P=0.001).慢性期胼胝体压部(0.621±0.002),胼胝体膝部(0.502±0.003),内囊后肢(0.613±0.009),半卵圆中心(0.448±0.004)FA值较急性期升高,但仍低于对照组.DTT示受损部位神经纤维失去正常形态.结论 DTI可以较敏感地检测DAI病灶,FA值可用以协助评估患者的病情,预测患者的预后.     

磁共振扩散张量成像在新生儿缺氧缺血性脑病中的应用价值

【摘要】目的：探讨磁共振扩散张量成像（DTI）在新生儿缺氧缺血性脑病（HIE）中的早期诊断价值。方法：搜集在本院行磁共振检查并经临床确诊的45例足月HIE患儿的病例资料，将其分为轻度组（18例）、中度组（15例）、重度组（12例）。选取正常新生儿20例作为正常对照组。所有研究对象均行常规MRI常规序列和DTI扫描，测量双侧额叶白质、双侧半卵圆中心、内囊前肢、内囊后肢、胼胝体膝部、胼胝体压部及豆状核兴趣区的部分各向异性（FA）值，比较分析各兴趣区FA值的变化规律并应用ROC曲线分析各兴趣区FA值诊断HIE的准确性。结果：轻度组中，胼胝体压部、内囊后肢的FA值（0.613±0.005，0.513±0.045）低于对照组（0.621±0.011，0.562±0.044），差异具有统计学意义（P＜0.05）；中度组中，额叶白质、半卵圆中心、胼胝体压部及内囊后肢的FA值（0.230±0.025，0.233±0.026，0.607±0.009，0.499±0.016）均低于照组（0.259±0.034，0.269±0.048，0.621±0.011，0.562±0.044），高于重度组（0.206±0.006，0.208±0.018，0.595±0.008，0.469±0.016），差异均具有统计学意义（P＜0.05）；除上所述兴趣区外，重度组内囊前肢、胼胝体膝部FA值（0.368±0.026，0.561±0.019）均低于对照组（0.420±0.043，0.596±0.012）、轻度组（0.406±0.039，0.588±0.013），差异均具有统计学意义（P＜0.05）。豆状核FA值在各组间差异无统计学意义（P＞0.05）；在各兴趣区中，内囊后肢FA值诊断HIE的效能最高，其FA值的取阈值0.531时，诊断敏感度为80%，特异度为84.4%，Youden指数为0.644。结论：同常规MRI序列相比，DTI技术能够早期、定量、客观评价HIE患儿脑损伤的情况，为HIE的早期诊断及病情评估提供客观依据。     

The role of interventional radiology in trauma

Introduction Interventional Radiology has evolved into a specialty having enormous input into the care of the traumatized patient.In all hospitals,regardless of size,the Interventional Radiologist must consider their relationships with the trauma service in order to     

Sexual homicide: Brief review of the literature and case report involving rape,genital mutilation and human arson

The objective of the current paper is to report a new case of sexual murder involving human arson and summarize the literature on the phenomenon of sexual homicide. The present case study is unprecedented in Greece and a rarity in international literature due to the fact that the victim suffered genital mutilation and incineration while still alive. The evaluation consisted of 176 articles; 53 were reviewed by the authors. The results revealed sparse, but significant, research findings. The authors discuss the limitations regarding research, incidence of the phenomenon, crime-scene patterns, offender characteristics (killing methods, motive inferences, sociodemographic data, classifications, psychopathology, modus operandi), and victim selection. The incidence of the phenomenon is unclear (1–4%) due to non-standardized criteria. It is an expression of displaced anger or sexual sadism and/or a way to elude detection (ancillary benefit). Most offenders (in their first kill) and victims were in their late 20s to early 30s and belong to Caucasian populations. Personal weapons were commonly used against women, strangulation is the prevalent killing method against children, and firearms against men. Most of the sexual homicide perpetrators are non-psychotic at the time of the attack, but experience personality pathology, primitive defenses, pathological object relations, and withdrawal into fantasy in order to deal with social isolation.     

Extension du modèle puissance–temps limite pour estimer la production d’énergie aérobie et anaérobie lors de l’exercice intense

Aim

Examine how the modelling of the relation between power and time to exhaustion can provide an estimation of the production of aerobic and anaerobic energy during intense exercise.

Current knowledge

The hyperbolic model made it possible to define the critical power corresponding to the maximal rate of energy renewed by aerobic metabolism. A new model distinguishing the critical power from the maximal aerobic power has been built to estimate more precisely the anaerobic contribution. Data from middle distance runners and subjects tested on cycle ergometer showed a relative contribution of anaerobic metabolism arising from critical power and increasing until around 10 % of total power when aerobic energy production reaches its maximum.

Prospects

Considering the slow component of oxygen uptake would provide a more precise analysis of energy production and transformation during exercise at high intensity.     

Beziehungen zwischen Aufprallgeschwindigkeit,Fahrzeugbeschädigungen,Frakturen und „Wurfweite” bei 50 tödlichen Fußgänger-PKW-Unfällen

Zusammenfassung Aus 160 Obduktionen von Fußgängern, die durch PKW getötet worden waren, sind 50 nach folgenden Gesichtspunkten ausgewählt worden:Auffahrunfälle Erwachsener mit gesicherten Angaben in den Gerichtsakten über Fahrzeugbeschädigungen, Zusammenstoßstellen, Endlage der Fußgänger und Bremsspuren. Aus diesen Daten wurden Ausgangs- und Aufprallgeschwindigkeiten berechnet sowie die Wurfweite der Fußgänger gemessen.Die Ausgangsgeschwindigkeiten, nach der Berechnung zwischen 32 und 95 km/h, lagen meistens etwas höher als die angegebenen Geschwindigkeiten. Zwischen Ausgangs- und Aufprallgeschwindigkeiten waren die Differenzen größer. Ab 12 km/h Aufprallgeschwindigkeit kam es bereits zu tödlichen Verletzungen. Auffallend ist die zweigipfelige Verteilung der Häufigkeit sowohl bei der Einteilung nach den Aufprallgeschwindigkeiten als auch nach den Deformationsarbeiten (Aufprallgeschwindigkeit: 26% bei 51–60 km/h und 22% bei 21 bis 30 km/h; Deformationsarbeit: 34% bei 39–200 kpm und 30% bei 701–1000 kpm).Bei Aufprallgeschwindigkeiten über 50 km/h wurden doppelt so viel Knochenbrüche an der Wirbelsäule und am Becken als bei Aufprallgeschwindigkeiten unter 50 km/h festgestellt.Bei 44 Fußgängerunfällen lag ein Drittel innerhalb der Erwartungsgrenze der Wurfweite nach Fiala, je ein Drittel aber darüber bzw, darunter.Das Beschädigungsbild und die Anstoßverletzungen geben Hinweise zur Ermittlung der Aufprallgeschwindigkeit, vor allem wenn weitere Berechnungsgrundlagen fehlen.

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Summary Fifty cases were selected from 160 autopsies performed on pedestrians who were accidentally killed by private motorcars; the cases were selected according to the following criteria:The cases were confined to impact accidents involving adults in which reliable evidence could be gathered from the Court records in relation to damage to the car, the place of collision, the final position of the injured pedestrian and the extent of skidmarks. The initial and collision speeds of the cars were calculated from these facts and the distance of projection of the pedestrians were measured.The initial speeds, calculated between 32 and 95 km/h, were, in most cases, higher than the declared speeds. The differences between initial and collision speeds were larger. Fatal injuries could arise from a collision velocity of only 12 km/h. A striking feature of the analysis was the distribution of two peaks of frequency whether these were classified according to the collision speeds or according to the deformation of the vehicle (collision speed: 26% at the speed of 51 to 60 km/h and 22% at the speed of 21 to 30 km/h; deformation work: 34% at the deformation work of 39 to 200 kpm and 30% at the deformation work of 701 to 1,000 kpm).Twice as many fractures of the vertebral column and pelvis were sustained at collision speeds over 50 km/h as were sustained under 50 km/h.In one third of 44 pedestrian accidents, the distance of projection was within the expected range described by Fiala; in one third the distance was above and in one third below the expected range.If additional data for calculation were lacking, the patterns in injury arising from the impacts gave indications from which it was possible to estimate the collision speed.

Stipendiat der Alexander v. Humboldt-Stiftung, Dozent Dr. med. S. Kamiyama, Dept. of Legal Medicine, School of Medicine, Chiba University, 313 Inohanacho, Chiba, Japan.     

Diagnóstico ecográfico del neumotórax

The ultrasonographic diagnosis of pneumothorax is based on the analysis of artifacts. It is possible to confirm or rule out pneumothorax by combining the following signs: lung sliding, the A and B lines, and the lung point. One fundamental advantage of lung ultrasonography is its easy access in any critical situation, especially in patients in the intensive care unit. For this reason, chest ultrasonography can be used as an alternative to plain-film X-rays and computed tomography in critical patients and in patients with normal plain films in whom pneumothorax is strongly suspected, as well as to evaluate the extent of the pneumothorax and monitor its evolution.     

Carbohydrate Supplementation during Exercise: Does It Help? How Much is Too Much?

KEY POINTS· Carbohydrate intake during exercise can delay the onset of fatigue and improve performance of prolonged exercise as well as exercise of shorter duration and greater intensity (e.g., continuous exercise lasting about 1h and intermittent high-intensity exercise), but the mechanisms by which performance is improved are different.     

磁共振DWI和动态增强鉴别颅底脊索瘤和侵袭性垂体瘤的应用

目的 探讨磁共振扩散加权成像(DWI)和动态增强在颅底脊索瘤和侵袭性垂体瘤(IPA)鉴别诊断中的应用价值.方法 搜集经手术病理证实且影像学有鞍区破坏的颅底脊索瘤患者15例、向鼻咽部侵犯的IPA患者20例.测量二者的表观扩散系数(ADC)值,绘制受试者工作特征曲线(ROC),分析动态增强曲线的类型,统计达峰时间(TTP)、增强峰值(EP)和最大对比增强率(MCER),分析各个参数在鉴别诊断中的价值.结果 颅底脊索瘤的ADC值为(1.274±0.07)×10-3mm2/s,高于IPA ADC值(0.672±0.03) ×10-3 mm2/s(P ＜0.001),ADC阈值为0.964×10-3mm2/s时,ROC曲线下面积为0.997,敏感度为93.3％,特异度为100％.颅底脊索瘤时间-信号强度曲线(TIC)Ⅰ型14例,TICⅢ型1例,此例TICⅢ型者TTP约40 s;IPA TIC Ⅰ型7例,TICⅢ型13例.颅底脊索瘤和IPA的EP、MCER差异均有统计学意义(P ＜0.001).结论 ADC值和TIC的类型及其相关参数(EP,MCER)有助于颅底脊索瘤和IPA之间的鉴别.     

Hip and pelvic injuries in the elderly

Fractures of the hip and pelvis are frequent and serious injuries in elderly patients. Due to the aging population, their incidence should double by 2050. Therefore, the social and economical implications of these fractures are significant. Delay in diagnosis increases the associated morbidity and mortality. The purpose is to review the imaging features of these fractures, the imaging techniques (projections, CT) to depict them and their classification based on severity.