含服硝酸甘油对64层螺旋CT冠状动脉成像质量影响的分析

目的 定量评估64层CT在冠状动脉成像中含服和不含服硝酸甘油对冠状动脉显示的差异.方法 分别在相对时段中对含服硝酸甘油(A组)和不含服硝酸甘油(B组)的各100例患者进行64层CT冠状动脉检查,2组受检者均采用回顾性后门控智能mA扫描技术.分别选取左、右冠状动脉的最佳期相进行MPR、MIP、CPR、VR重组.对2组图像分别进行冠状动脉10个测量点管径的测量,并对右冠状动脉、前降支、回旋支3支冠状动脉显示的分支数目进行统计,然后对2组图像管径测量值和分支数目采用完全随机的两样本均数t检验进行统计学比较.结果 右冠状动脉近、中、远段管径A组比B组分别增加0.29、0.17、0.11mm,扩张率分别为8.0%、5.0%、4.0%;前降支分别增加0.40、0.23、0.10 mm,扩张率分别为11.0%、8.0%、4.7%;回旋支分别增加0.42、0.35、0.12 mm,扩张率分别为13.5%、12.5%、5.5%;左主干增加0.31 mm,扩张率7.8%.A组较B组分支数目增加率,右冠状动脉、前降支、回旋支分别为83%、80%、113%.A、B 2组冠状动脉10个血管节段中,右冠状动脉近段、左主干、前降支近、中段、回旋支近、中段差异有统计学意义(t值分别为3.86、3.74、5.35、3.58、5.29、4.64,P值均＜0.01);右冠状动脉中、远段、前降支远段、回旋支远段差异亦有统计学意义(t值分别为2.13、2.58、2.35、2.14,P值均＜0.05).结论 服用硝酸甘油能有效扩张冠状动脉并能有效增加冠状动脉分支的显示,从而提高64层CT冠状动脉成像质量.     

Lenke 1型青少年特发性脊柱侧弯脊柱-骨盆矢状位与冠状位参数的相关性

目的：探索Lenke 1型青少年特发性脊柱侧弯（ adolescent idiopathic scoliosis, AIS）患者的脊柱-骨盆矢状位参数与冠状位参数的相关性。方法：回顾2005年4月至2013年11月北京大学第三医院诊治的Lenke 1型AIS患者,在正、侧位片上测量和记录顶锥（apical vertebra, AV）位置、主胸弯Cobb角（main thoracic, MT）,以及骨盆入射角（pelvic incidence, PI）、C7转移比值（C7 translation ratio, C7TR）等矢状位参数,运用统计软件进行参数间的比较和相关性分析。结果：共收集病例51例,其中男18例,女33例,平均年龄（14．9±2．0）岁,顶锥位置在T7～T11, MT为（49．6°±16．7°）,PI值为（44．7°±6．7°）。 PI与PT、SS和LL,LL与SS和TK等有相关性（P均＜0．05）。不同腰椎修饰（ lumbar modifiers, LM）组的TK、LL、PT差异具有统计学意义,其他矢状位参数差异无统计学意义。 AV位置与脊柱-骨盆矢状位各参数相关性不显著, MT与TK、LL、SS显著相关,与PI相关性不显著。结论：Lenke 1型AIS的多数脊柱-骨盆矢状位参数间显著相关,形成以PI为核心的矢状位平衡调节链,部分冠、矢状位参数间有显著相关性。     

Markerless motion capture can provide reliable 3D gait kinematics in the sagittal and frontal plane

Estimating 3D joint rotations in the lower extremities accurately and reliably remains unresolved in markerless motion capture, despite extensive studies in the past decades. The main problems have been ascribed to the limited accuracy of the 3D reconstructions. Accordingly, the purpose of the present study was to develop a new approach based on highly detailed 3D reconstructions in combination with a translational and rotational unconstrained articulated model. The highly detailed 3D reconstructions were synthesized from an eight camera setup using a stereo vision approach. The subject specific articulated model was generated with three rotational and three translational degrees of freedom for each limb segment and without any constraints to the range of motion. This approach was tested on 3D gait analysis and compared to a marker based method. The experiment included ten healthy subjects in whom hip, knee and ankle joint were analysed. Flexion/extension angles as well as hip abduction/adduction closely resembled those obtained from the marker based system. However, the internal/external rotations, knee abduction/adduction and ankle inversion/eversion were less reliable.     

乳腺癌新辅助化疗早期肿瘤直径MRI变化率和病理分级评价化疗疗效的意义

目的 探讨乳腺癌新辅助化疗早期肿瘤最大径变化率,以及肿瘤治疗前和术后组织病理学变化,评价化疗疗效的意义.方法 49例乳腺癌患者,新辅助化疗前和术后均具有完整的组织病理结果;新辅助化疗前和化疗第2周期后及术前行3次乳腺增强MR检查,分别于注入对比剂前和注药后连续采集8次(8个时相).注射对比剂后2 min的图像与蒙片减影后行MIP重组.在MIP图像上测量肿块的最大径线(△d),根据△d值将直径变化率分为6级.根据实体肿瘤的疗效评价标准(RECIST)设△d晚≥30%为金标准,通过ROC分析观察△d早在判断疗效时的敏感度和特异度.病理分级与RECIST标准间进行Spearman相关分析.结果 新辅助化疗有效30例,无效19例.Ad早 10%时,评价疗效的敏感度为96.7%(29/30),特异度为84.2%(16/19);曲线下面积0.960.病理分级与RECIST标准间具有相关性(r=0.613,P=0.000).结论 新辅助化疗早期通过直径评价疗效,将阈值设为10%,其敏感度和特异度均较高.病理评价疗效与RECIST径线评价疗效间具有一定相关性,但病理评价会导致高估疗效.     

高低位腰椎椎间盘突出症患者脊柱-骨盆矢状面形态变化

目的 比较高位与低位腰椎椎间盘突出症（LDH）患者脊柱-骨盆矢状面形态学差异，探讨脊柱-骨盆矢状面形态学参数异常与高位LDH发生的关系。方法 纳入2006年1月—2022年1月收治的高位LDH患者53例（高位组），同时期性别、年龄和体质量指数（MBI）匹配的低位LDH患者53例（低位组）及单纯下腰部疼痛的非LDH患者53例（对照组）。在站立位全脊柱侧位X线片上测量3组矢状面平衡（SVA）、胸椎后凸角（TK）、腰椎前凸角（LL）、腰骶前凸角（LSL）、骶骨倾斜角（ST）、骨盆入射角（PI）、骨盆倾斜角（PT）、骶骨倾斜角（SS）等脊柱-骨盆矢状面参数。结果 高位组SVA、TK明显高于对照组，LL、ST、PI、PT及SS明显低于对照组；高位组TK明显高于低位组，LL、ST及PI明显低于低位组；差异均有统计学意义（P<0.05）。高位组L₁/L₂节段患者的LL、ST较L₂/L₃节段患者有下降趋势，但差异无统计学意义（P>0.05）。结论 骨盆水平化导致的胸腰段过度代偿可能是高位LDH发生、发展的机制之一。     

Reliability of reference distances used in photogrammetry

Objective:To determine the reliability of the reference distances used for photogrammetric assessment.Materials and Methods:The sample consisted of 100 subjects with mean ages of 22.97 ± 2.98 years. Five lateral and four frontal parameters were measured directly on the subjects'' faces. For photogrammetric assessment, two reference distances for the profile view and three reference distances for the frontal view were established. Standardized photographs were taken and all the parameters that had been measured directly on the face were measured on the photographs. The reliability of the reference distances was checked by comparing direct and indirect values of the parameters obtained from the subjects'' faces and photographs. Repeated measure analysis of variance (ANOVA) and Bland-Altman analyses were used for statistical assessment.Results:For profile measurements, the indirect values measured were statistically different from the direct values except for Sn-Sto in male subjects and Prn-Sn and Sn-Sto in female subjects. The indirect values of Prn-Sn and Sn-Sto were reliable in both sexes. The poorest results were obtained in the indirect values of the N-Sn parameter for female subjects and the Sn-Me parameter for male subjects according to the Sa-Sba reference distance. For frontal measurements, the indirect values were statistically different from the direct values in both sexes except for one in male subjects. The indirect values measured were not statistically different from the direct values for Go-Go. The indirect values of Ch-Ch were reliable in male subjects. The poorest results were obtained according to the P-P reference distance.Conclusions:For profile assessment, the T-Ex reference distance was reliable for Prn-Sn and Sn-Sto in both sexes. For frontal assessment, Ex-Ex and En-En reference distances were reliable for Ch-Ch in male subjects.     

A systematic review of photogrammetry as a reliable methodology in gender identification of human skull

One of the most important parameters in the identification process in forensic Medicine and Dentistry is the determination of sex through the skull, based on morphological and metric dimorphism. Photogrammetry is an affordable option that allows the reconstruction of position, orientation, shape, and size, allowing the performance of quantitative and qualitative analyzes to identify the sex of the individual. However, there are few systematic reviews in the literature validating whether photogrammetry is a reliable methodology for sexual identification using human skulls. Therefore, the objective of the current systematic review was to validate whether photogrammetry of dry skulls is reliable as a method for calculating sex in human identification. This revision follows the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) and was recorded in the Prospective International Systematic Reviews Registry (PROSPERO) (CRD420223 Systematic Registry) (CRD420223). The inclusion criteria for selecting the studies were based on the PICO question: “Is test photogrammetry reliable as a method for estimating sex in human identification?“. A literature search for studies was performed in the databases MEDLINE Scopus, Web of Science, LILACS, and the Cochrane Library. The Kappa agreement presented an approval level of (k = 0.93). This systematic review analyzed 11 ex-vivo studies published between 2001 and 2021. The risk of bias was considered low in 8 of the studies, and high in 3 studies. Based on this systematic review, it can be concluded that the photogrammetry method is viable and reliable in identifying sexual dimorphism.