体表损伤与瘢痕的三维测量方法应用评估

目的检验结构光三维扫描法和单相机摄影测量法这两种三维测量方法在法医学体表损伤与瘢痕测量中的准确性和可靠性。方法对比分析直尺法、结构光三维扫描法和单相机摄影测量法对86处尸体损伤的测量结果;对比分析结构光三维扫描法、单相机摄影测量法、Photoshop套索像素法、PDF阅读软件法对13处活体模拟块状瘢痕面积的测量结果,并记录所耗时间;以贴纸的已知规格信息作为标准值,比较直尺法、结构光三维扫描法和单相机摄影测量法的测量准确度,计算均方根误差(root mean square error,RMSE);对不同操作者和同一操作者前后3次测量结果的可重复性进行组内相关系数(intraclass correla⁃tion coefficient,ICC)一致性评价。结果两种三维测量方法与直尺法在尸体损伤上测得的结果差异无统计学意义;结构光三维扫描法、单相机摄影测量法、PDF阅读软件法的测量结果和Photoshop套索像素法相比差异无统计学意义,单相机摄影测量法后处理耗时长于其他方法;直尺法测量长距离组(10~40cm)时结果小于标准值,RMSE值结果为结构光三维扫描法<单相机摄影测量法<直尺法;组内和组间的ICC值均大于0.99。结论结构光三维扫描法和单相机摄影测量法均可应用于法医学体表损伤的记录和测量,前者在测量精度及稳定性上表现更优,后者的数据色彩还原度更好,但后处理耗时较长。     

结构光三维扫描技术测量损伤瘢痕的法医学应用

目的验证结构光三维扫描技术测量体表规则或不规则损伤瘢痕的长度和面积的准确性与可靠性,探讨其法医学应用价值。方法采用软尺、游标卡尺+细线法、结构光三维扫描法分别对30例模拟条状瘢痕与50例伤后条状瘢痕的长度进行测量,以长×宽、薄膜描记结合坐标纸法、像素法、结构光三维扫描法分别测量35例模拟片状瘢痕及15例伤后片状瘢痕的面积,并进行统计学分析。结果结构光三维扫描法测量的模拟条状瘢痕长度与标准长度差异无统计学意义;对表面曲率较大且大面积不规则模拟片状瘢痕和伤后片状瘢痕进行测量时,结构光三维扫描法测量结果与标准面积差异无统计学意义。使用结构光三维扫描法对50例伤后条状瘢痕长度进行测量时,两名操作人员测量结果的相关系数为0.998,同一操作者两次测量结果的相关系数为1.000,与游标卡尺+细线法测量结果的相关系数为0.996。结论采用结构光三维扫描技术测量可获取体表瘢痕的立体信息,对瘢痕长度和面积的测量不受部位、体表曲率及人为因素的影响,测量结果准确可靠,具有独特的优势。     

Photoshop软件在法医临床学鼻面积测量中的应用初探

在鼻部损伤的法医临床学鉴定中,由于鼻的形态不规则,法医学界对鼻部缺损范围的测量和计算尚无一种统一的、精确的方法。本文利用Photoshop软件与传统的薄膜覆盖法分别对鼻面积进行测量,分析两种测量方法所得结果无统计学差异,因此通过软件法可以简便准确的计算鼻部面积。在伤者受伤前与伤后眼裂等器官长度不变的条件下,将伤者眼裂长度作为伤前照片的"比例尺",根据伤前照片推算其伤前鼻部面积,从而计算出鼻缺损比例,为鼻损伤程度的判定提供了更科学的方法。     

应用Pixel法测量不规则体表瘢痕面积

正体表瘢痕在法医鉴定中很常见,由于瘢痕形态多为不规则,用一般测量面积的方法会产生较大误差。本文介绍一种应用薄膜描记+图像处理软件PhotoShop测量体表瘢痕的方法—Pixel法(本文称像素法),该方法不但可较精确计算瘢痕面积,同样也适用于器官缺损面积(如耳廓缺损)、皮肤色素面     

外伤性鼓膜穿孔面积测定方法及41例分析

目的探索外伤性鼓膜穿孔面积大小的测量方法并分析41例病例。方法用图像分析软件Photoshop分析耳内窥镜获得的外伤穿孔鼓膜照片,计算穿孔与鼓膜面积比例并分析外伤性鼓膜穿孔的法医临床学特性。结果外伤性鼓膜穿孔通常为小穿孔,边缘血污部分外翻,形状不规则,左侧居多。结论耳内窥镜可以清晰记录外伤性鼓膜穿孔,图像处理软件可以定量分析鼓膜穿孔大小。     

三种不规则体表损伤面积测量法的比较

正《人体损伤程度鉴定标准》中有很多涉及损伤面积的条款,如皮肤缺损、色素异常以及烧烫伤、擦挫伤等面积,而很多分布在体表上的损伤形态极不规则,如何精确测量其面积是评定损伤程度的关键。笔者认为,利用计算机图形处理软件测量不规则损伤面积结果较为准确,目前广泛应用的软件有Photoshop、AutoCAD等,还有一款是公安业务软件图像浏览编辑器,本研究用这三种软件对同一损伤处面积进行测量并比较。     

外伤性鼓膜穿孔面积测定方法及41例分析

目的探索外伤性鼓膜穿孔面积大小的测量方法并分析41例病例。方法用图像分析软件Photoshop分析耳内窥镜获得的外伤穿孔鼓膜照片，计算穿孔与鼓膜面积比例并分析外伤性鼓膜穿孔的法医临床学特性。结果外伤性鼓膜穿孔通常为小穿孔，边缘血污部分外翻，形状不规则，左侧居多。结论耳内窥镜可以清晰记录外伤性鼓膜穿孔，图像处理软件可以定量分析鼓膜穿孔大小。     

Photoshop图像分析法在不规则瘢痕鉴定中应用

目的 探讨photoshop图像分析方法在不规则瘢痕鉴定中的应用价值.方法 用photoshop图像分析方法和数格法对30种不规则瘢痕进行面积计算,并对其准确性和实用性进行比较.结果 photoshop图像分析方法与数格法所计算出的面积之间无明显差异(P =0.960 7),而在检测时间和过程等方面photoshop图像分析方法明显优于数格法.结论 photoshop图像分析法用于不规则瘢痕的面积计算,具有既准确又节省时间的优点,可以在不规则瘢痕的法医学鉴定中选择使用.     

眼球突出度测量方法的比较及其法医学意义

目的比较Hertel突眼度计及CT测量两种眼球突出度测量方法的差异,探讨其法医学应用价值。方法选取56例眼部无损伤及疾病的正常人作为正常组,在确定规范的CT影像工作站上测量眼球突出度绝对值,并比较双眼眼球突出度有无差异。选取47例单侧眼眶骨折的伤者,根据两眼有无眼眶骨折,将其分为伤眼组及健眼组,分析Hertel突眼度计及CT测量两种方法测得同一眼眼球突出度绝对值的差异以及同一受检者双眼眼球突出度相对差值的差异。结果 CT法测量正常人双眼间眼球突出度差异无统计学意义。健眼组CT法测得眼球突出度绝对值为(16.66±5.41)mm,Hertel突眼度计测得眼球突出度绝对值为(16.16±4.45)mm,两组测量结果之间差异无统计学意义(P0.05)。伤眼组应用两种方法测量的眼球突出度绝对值之间差异具有统计学意义(P0.05)。两种测量方法测得的眼球突出度相对差值在伤眼和健眼组之间差异无统计学意义(P0.05)。结论 CT法与突眼度计法具有较好的一致性,可以运用于法医学鉴定实践。     

应用计算机软件准确计算耳廓缺损面积比例的方法

在人体轻、重伤鉴定标准里存在着较多需要计算不规则面积比例的条款,不规则面积的比例大小直接决定了伤情的结论或伤残等级,因此,准确、快捷地测量出人体某部分面积的比例是法医工作的迫切需求。传统有目测法、贴纸加方格法、微积分法等计算方法,但都存在着一些缺点。如目测法的主观性影响很大,不同检验人得出的结论可以完全悖异;贴纸法操作复杂,计算过程中受人为操作的影响偏大;微积分法相对客观,准确性高,但计算繁琐,不利于日常检验。鉴于上述方法存在的缺陷,本文作者在探索后总结出了一套运用计算机软件准确计算不规则面积比例的方法,将…     

身高推断的法医学研究进展CSCD

个体身高推断是法医人类学个体识别的重要内容之一,目前常借助直接测量或放射学技术收集一定群体的四肢长骨、不规则骨、体表解剖标志的数据建立回归方程来实现。由于人口流动性的增加、人类体质整体提高的影响以及种族和地区间的差异,身高推断的研究应成为常规性研究。本文对不同身高推断方法进行回顾性综述,简要阐述各方法的优缺点,并展望身高推断的研究方向。     

Two-dimensional linear analysis of dynamic bare footprints: A comparison of measurement techniques

In forensic intelligence-gathering, footprints have been shown to be valued evidence found at crime scenes. Forensic podiatrists and footprint examiners use a variety of techniques for measuring footprints for comparison of the crime scene evidence with the exemplar footprints. This study examines three different techniques of obtaining two-dimensional linear measurement data of dynamic bare footprints. Dynamic bare footprints were gathered from 50 students from a podiatric medical school using the Identicator® Inkless Shoe Print Model LE 25P system. After obtaining 100 bilateral footprints from the participants, the quantitative measurement data were collected by using three different measurement techniques: (i) a manual technique using a ruler (direct technique); (ii) an Adobe® Photoshop® technique; and (iii) a GIMP (GNU Image Manipulation Program) technique. The seven Reel linear measurement methodology was used for producing measurements using these three techniques.This study showed that all the mean bare footprint measurements on the right and left feet obtained using the direct technique were larger than those obtained using GIMP and Adobe® Photoshop® images. Differences were also observed in measurements produced using GIMP software and Photoshop images. However, the differences observed in the three techniques used for bare footprint measurements were not found to be statistically significant. The study concludes that there are no significant differences between the three measurement techniques when applied to two-dimensional bare footprints using the Reel method. It further concluded that any of these measurement techniques can be used when employing the Reel methodology for footprint analysis without significant difference.     

角度测量软件测量图像关节运动活动度研究

目的探索一种直接利用电脑角度测量软件测量电子数据照片图像中人体肢体大关节运动活动度的方法。方法使用通用量角器测量腕、踝关节获得实时数据,照相机分别在置有量角器作为参照和未置量角器参照的两种情形下对腕、踝关节运动活动度进行拍照固定,固定后的电子数据图像经电脑角度软件测量获得有参照物和无参照物两组角度测量数据。将各关节在各运动方向上的实时测量、有参照物照相测量及无参照物照相测量等三组活动度数据进行统计分析比较。结果三种测量方法测得的腕、踝各关节运动活动度数据两两比较均无统计学差异,测量结果相同,两种角度软件测量法测量的数据精确度较实时测量均略有提高,且图像中有参照物时更方便软件测量。结论角度软件测量法经济、快速、相对准确、可重复操作,在基层法医临床鉴定工作中对肢体大关节运动活动度的测量具有一定的应用优势。     

A Novel Pixel‐Based Method to Estimate the Instantaneous Velocity of a Vehicle from CCTV Images

In traffic forensic identifications, it was usually unfavorable that estimated velocities of questioned vehicles derived from frame‐based methods eventually turned out to be close to but a bit less than speed limits. In this paper, a novel pixel‐based method was presented to estimate vehicles’ relatively instantaneous velocities. First, two adjacent pixels’ actual distance was acquired from the closed‐circuit television (CCTV) images. Then, the instantaneous average velocity within this one frame interval time (FIT) was calculated out. The frame‐based method and its evaluating result were also introduced in this paper. The results showed that the velocity estimated by this new pixel‐based method was higher than which derived from the frame‐based method. Employing this presented novel method in these cases, it could be more accurately identified whether or not the vehicles had exceeded the speed limits, and then the responsibilities could be consequently assigned impartially.     

Application of non-contact scanning to forensic podiatry: A feasibility study

Foot impression evidence recovered from crime scenes can be available in the form of barefoot prints, sock-clad footprints, or as impressions within footwear. In some cases, suspects leave their footwear at the scene of the crime, and the insoles from the footwear can be important in linking a person to the footwear. The application of 3D data-collecting technology is becoming more and more popular within forensic science and has been used to recover footwear impression evidence. The present study is a feasibility study to discover if 3D data capturing devices can be applied to insoles; to capture the footprint impression for measurement using the Gunn method (a method used in forensic podiatry casework). Three different methods of data capture were conducted; Adobe Photoshop, MeshLab, and calipers used directly on the insole. Paired t-tests and Intraclass Correlation Coefficient (ICC) were conducted for all three data capture methods. Seven measurements used in this study were significantly different across all three methods. ICC scores were moderate to excellent for the Photoshop method, poor to good for the 3D method, and moderate to excellent for the Direct method.     

Yet another method for marking incisal edges of teeth for bitemark analysis

Over the years many methods have been proposed and presented for marking or "highlighting" the incisal edges of anterior teeth on a dental stone model -- one of the critical steps in production of transparent overlays for bitemark analysis. A method is presented here that is an extension and refinement of the "paint the edges" method shown at least as early as 1966 by Gustafson. This method uses "invisible ink" and ultraviolet illumination to produce a very high contrast image of the incisal edges of the teeth on the model. The advantages of this new method are that it is nondestructive, it does not leave visible marks on the models, operator subjectivity in selecting the portions of anterior teeth to be highlighted is reduced, and the author submits that this technique lends itself to easy construction of overlays using computer image-processing software such as Adobe Photoshop and ImageJ.