高度近视者眼球结构及其功能变化的法医学意义

高度近视者眼球可发生一系列不可逆的组织形态学改变。其中,眼轴、角膜曲率、前房深度、眼底形态、黄斑神经上皮厚度等改变与眼球的屈光状态及视觉功能有着密切的关系,玻璃体混浊、玻璃体脱离、白内障、青光眼、后巩膜葡萄肿、视网膜脱离等并发症的发生率也随着近视屈光度数的加深而增高。越来越多的研究表明高度近视者视觉功能改变是上述多种结构变化共同作用的结果。因此有望通过应用多项检查方法观察高度近视者眼球的结构变化,并根据这些变化分析评估高度近视者视觉功能的损害程度,为法医学评价眼部外伤与疾病的关系以及眼外伤的司法鉴定提供支持和依据。     

自己捆绑手脚溺水自杀1例

1案例1.1简要案情某晚,在一河面发现一具男子尸体,尸体四肢被捆绑。1.2尸体检验死者为成年男性,尸长170cm,发育正常,尸僵较弱,尸斑不明显,皮肤呈鹅皮样改变,眼结膜充血及点状出血,角膜中度混浊,尚可透视瞳孔,口鼻腔内见有     

外伤性胃破裂死亡法医学检验2例

1　案例简介例 1.某男 ,8岁 ,某年 3月 2 3日下午 2时 30分许 ,行走时被一货车撞倒 ,造成腹部、左下肢及背部多处软组织挫伤 ,经医院治疗无效于当日下午 7时 15分死亡。死后 6小时尸检 :儿童尸体 ,角膜轻度混浊 ,双下睑结膜及口唇粘膜有针尖样出血点。头皮及颅骨无损伤 ,镜下脑     

特殊眼外伤视力认定的分析

在法医鉴定中，眼外伤较常见，且比较复杂其主要需要解决的是损伤眼的视力问题，本文就４例特殊情况下眼外伤的鉴定，对外伤后无晶体眼或角膜移植的视力的认定作初步探讨。１案例资料例１董某，男，１９岁，于１９８７年被人用铅笔刀刺伤右眼，伤后查右眼角膜有７mm横行裂口，前房混浊，大量晶体质进入前房，晶体混浊，视力光感，行晶体吸出术，后行人工晶体植入。５年后查视力右眼０．９。例２陈某，男，１８岁，于１９９４年元月被人用树枝击伤左眼，伤后检查：左眼视力无光感，眼压Tn，左眼睫状充血，角膜中央有一闭合伤口，角膜表面不…     

放射状角膜切开术后外伤参与度分析1例

放射状角膜切开术(RK)是目前国内外广泛开展的手术治疗近视眼的方法,疗效较好。但术后角膜从切痕处破裂的现象常有发生,尤其是术后早期。笔者结合1例术后5年外伤致角膜破裂的案例,从组织学角度,对RK术后角膜张力的变化及角膜的外伤参与度进行分析探讨。1　案例资料赵某,男,27岁。5年前因近视行双眼放射状角膜切开术,现因右眼拳击伤来法医门诊。检查见右眼视力光感,左眼0.8;右眼睑肿胀淤血,球结膜下大片出血;双眼角膜均见8条放射状瘢痕,右眼角膜3～9点子午线两条瘢痕贯通裂开,伤口处有出血痕迹及少许色素组织残留;前房大量积血,虹膜、晶体…     

角膜AQP1含量变化与死亡时间关系的法医学研究

目的观察角膜AQP1含量变化与死亡时间的关系。方法50只家兔随机分为10组,以空气栓塞方法致死,于死后不同时间取出角膜。应用免疫组织化学方法观察角膜AQP1含量变化,并采用图像分析方法测定AQP1阳性面积、积分光密度、平均光密度、平均灰度等参数,对各参数与死亡时间的关系进行统计学分析。结果死后84h内,角膜AQP1呈阳性着色,死后96h未见着色。图像分析结果显示,随着死后时间的延长,角膜AQP1各参数呈逐渐下降的趋势,并获得了上述各参数与死亡时间变化关系的回归方程。结论家兔死亡后角膜AQP1的含量呈现出规律性变化,其参数阳性面积、积分光密度、平均光密度、平均灰度等可以作为推测死亡时间的参考指标。     

死后18天特殊尸体现象1例

正1案例资料简要案情李某,女,3岁。某年12月25日在本村玩耍时失踪,经多方寻找,于次年1月12日上午在该村麦田地坟旁发现李某尸体。现场勘查现场位于该村北岗地上的坟头和土路之间,为顺风口,尸体头西北脚东南侧卧位,尸体下面有发黄枯萎的麦苗,尸长135cm,身穿连体棉衣及秋衣秋裤,棉袜棉鞋。尸体检验尸斑指压不褪色,尸僵未完全缓解,一侧角膜清晰可辨,另侧角膜轻度混浊,口唇紫绀,腹     

B超探查在眼外伤法医临床学鉴定中的应用

<正> B超探查图像能在屈光间质混浊情况下,清楚地显示眼球后段各组织结构的损伤或病变,以及准确进行眼球轴测量。B超探查从60年代已应用于眼科各种疾病的诊断。本文通过对263例眼外伤患者的眼B超图像,显示眼球不同部位结构的损伤及损伤恢复过程中临床生理、生物学变化进行分析,探讨B超探查在眼外伤法医临床学鉴定工作中客观地反映眼损伤、恢复情况的作用。     

犬角膜死后变化的初步观察

尸体角膜的死后变化是法医实践中用以判断死后时间的最重要的早期指征之一,但有关这方面的研究迄今报告不多.为了深入探讨,我们利用心脏电生理实验后的犬,经过心脏放血处死后,对其角膜死后变化进行了光镜和电镜观察,现报告如下:     

采用LC-MS/MS法检验阿维菌素中毒死亡

<正>1案例检验1.1简要案情及尸体检验傅某,男,34岁。2013年6月某日被发现死亡,其衣着整齐,现场无打斗迹象,距尸体5m处发现内有半瓶液体的标有"阿维菌素"字样的药瓶1个。尸体轻度腐败,尸斑暗红色,指甲及嘴唇紫绀,双眼角膜中度混浊,瞳孔放大,其它未见异常。1.2毒物分析检验样本前处理提取死者心血、胃组织及标有"阿维菌素"字样药瓶中的液体。样本(组织样本匀浆     

Corneal‐Smart Phone: A novel method to intelligently estimate postmortem interval

The changes of postmortem corneal opacity are often used to roughly estimate the postmortem interval (PMI) in forensic practice. The difficulty associated with this time estimate is the lack of objective means to rapidly quantify postmortem corneal changes in crime scenes. This study constructed a data analysis model of PMI estimation and implemented an intelligent analysis system for examining the sequential changes of postmortem corneal digital images, named Corneal‐Smart Phone, which can be used to quickly estimate PMI. The smart phone was used in combination with an attachment device that provided a darkroom environment and a steady light source to capture postmortem corneal images. By segmenting the corneal pupil region images, six color features, Red (R), Green (G), Blue (B), Hue (H), Saturation (S), Brightness (V) and four texture features Contrast (CON), Correlation (COR), Angular Second Moment (ASM), and Homogeneity (HOM), were extracted and correlated with PMI model. The results indicated that CON had the highest correlation with PMI (R² = 0.983). No intra/intersubject variation in CON values were observed (p > 0.05). With the increase in ambient temperature or the decrease in humidity, the CON values were increased. PMI prediction error was <3 h within 36 h postmortem and extended to about 6–8 h after 36 h postmortem. The correct classification rate of the blind test samples was 82%. Our study provides a method that combines postmortem corneal image acquisition and digital image analysis to enable users to quickly obtain PMI estimation.     

家兔死后不同时间角膜基质胶原纤维的超微结构观察

目的探讨角膜基质胶原纤维直径变化与死亡时间的关系。方法28只家兔空气栓塞致死后,按死后不同时间取角膜,常规方法制作超薄切片,应用透射电镜观察角膜基质0.5μm×0.5μm区域内的胶原纤维,并用图像分析系统测量反映胶原纤维直径变化的横切面面积(Y1)、周长(Y2)、平均直径(Y3)、等效直径(Y4)4个参数,所得数据用EXCEL2000和SPSS10.0软件进行统计分析。结果在死后0～72h内,角膜胶原纤维横断面的面积从1131±53nm增加到1628±26nm,周长从132.8±23nm增加到167.5nm,等效直径从38nm增加到45nm,平均直径从37.71±6nm增加到44.89±5nm。结论死后72h内,角膜基质胶原纤维直径随死后时间的延长逐渐增大,4个参数有望作为判断死后时间的新指标。     

The morphogenesis of electrically and heat-induced dermal changes in pig skin

In order to establish pathological evidence in dermis for distinguishing between sequelae of electrical torture and those of other superficial injuries, the skin of eleven fully anaesthetized Danish Landrace pigs have been exposed to heat and electrical energy from either 50 Hz alternating current (a.c.) or direct current (d.c.) via 12 mm large contact knobs or via a pointed 0.5 mm large electrode (only 50 Hz a.c.). The lesions have been examined from 1 to 126 days after the injury. While heat lesions exposed to energy lower than 60 joule only gave minor changes, heat lesions exposed to more than 60 joule showed changes in both collagen fibres (basophilic or eosinophilic fibres without any birefringence or coarse cross-striation in polarized light, respectively) and dermal cells (granular cytoplasm). Areas exposed to 50 Hz a.c. via 0.5 mm. electrode showed basophilic collagen fibres and in a few biopsies on day 7 calcium salts on collagen fibres. Using 12 mm large electrodes the changes were minor, but basophilic and eosinophilic collagen fibres with no birefringence or with fine/coarse cross-striation respectively were seen. Even cells with 'vesicular nuclei' were seen on day 1 and 2 after the injury. The changes in the anode area showed resemblance to that of heat lesions (basophilic collagen fibres). Eosinophilic collagen fibres with fine densely spaced cross-striation in polarized light and 'vesicular nuclei' as well as collagen fibres with calcium salts were seen in the cathode lesions. It is concluded that the dermal changes in the cathode area are specific for electrical injury from day 1 to 14. However, earlier studies have demonstrated dermal changes specific for electrical injury at day 0 and the presence of calcified collagen fibres up to 2 months after injury. The dermal changes in anode lesions were non specific and could not be differentiated from those found in heat lesions. Alternating current lesions (50 Hz) were specific from day 1 to day 7, when the pointed electrode was used, but only in a few days when the energy was transferred via the 12-mm electrodes.     

Bullet or bite--a contribution to the morphogenesis of gunshot dermal injury

Histopathologic studies of dermal dog bites revealed changes identical with those observed in distant gunshot skin entrance wounds and in a presternal skin stab wound made by a screwdriver. The similarity of the epithelial and collagen changes produced by these three totally different traumatizing, perforating agencies indicate that it is the bullet's penetrating and crushing power, and not its caloric content, that is responsible for the characteristic dermal collagen changes noted in these common injuries.     

The significance of collagen in determining the age of a wound

The aim of the present study was to find out whether the quantitative and/or qualitative analysis of collagen can be useful in the determination of the age of healing skin wounds in various body regions of patients of different ages and sex. The quantitative measurement of total wound collagen revealed no clear time-dependent changes. Immunohistochemical staining for collagen types I and III demonstrated the presence of type III as early as 2 days after injury. Procollagen type I was found in wounds beginning from 4 days on, while type I collagen was not present before 6 days after the injury. Immunohistochemical analysis of specific basement membrane proteins, collagen type IV and laminin, showed a reconstruction of the epithelial basement membrane beginning from on day 5, while a completely rebuilt basement membrane was found in most cases after more than 14 days, depending on the dimension of the wound and its treatment.     

Electrically-induced collagen calcification in pig skin. A histopathologic and histochemical study

Deposition of calcium salts on collagen fibres in skin of fully anaesthetized pigs was induced by exposure to direct current (d.c.). In biopsies obtained from cathode areas successively from day 1 to day 7 after exposure the histopathologic and histochemical changes before and after the initial deposition of calcium salts have been examined. For comparison skin sites with intradermal injected calcium hydroxyapatite crystals were studied in addition. Small areas of calcified collagen and elastic fibres were noted in viable tissue 2 days after d.c. exposure. In succeeding days the calcified areas enlarged with new deposits always more superficial and closer to the epidermis than the original calcium deposits. Preconditions for calcification appear to be (1) a pH change in basic direction and/or the electrochemical processes specific to the cathode area and (2) a viable tissue. Elastic fibres appear to have a lower calcification threshold than collagen fibres. A positive staining for glycoproteins (PAS) and glycosaminoglycans (alcian blue pH 2.5) was noted in the calcified collagen fibres simultaneously with the calcification. In succeeding days the intensity of the staining reactions increased. Whether changes in the glycoproteins, collagen and its intimately bound glycosaminoglycans precede the calcification or the staining reactions develop secondarily to this deposition is not known. However, seven days after intradermal injections of Ca-apatite crystals in pig skin small and large crystals were observed ultrastructurally without any relation to collagen fibrils, but the calcified tissue presented a positive PAS and alcian blue reaction from day 2. Thus the PAS and alcian blue stainings in this model develop secondary to the deposition of calcium salts.     

Post-mortem Iris Decomposition and its Dynamics in Morgue Conditions

With increasing interest in employing iris biometrics as a forensic tool for identification by investigation authorities, there is a need for a thorough examination and understanding of postmortem decomposition processes that take place within the human eyeball, especially the iris. This can prove useful for fast and accurate matching of antemortem with postmortem data acquired at crime scenes or mass casualties, as well as for ensuring correct dispatching of bodies from the incident scene to a mortuary or funeral homes. Following these needs of forensic community, this paper offers an analysis of the coarse effects of eyeball decay done from a perspective of automatic iris recognition. We analyze postmortem iris images acquired for a subject with a very long postmortem observation time horizon (34 days), in both visible light and near-infrared light (860 nm), as the latter wavelength is used in commercial iris recognition systems. Conclusions and suggestions are provided that may aid forensic examiners in successfully utilizing iris patterns in postmortem identification of deceased subjects. Initial guidelines regarding the imaging process, types of illumination, and resolution are also given, together with expectations with respect to the iris features decomposition rates. Visible iris features possible for human, expert-based matching persists even up to 407 h postmortem, and near-infrared illumination is suggested for better mitigation of corneal opacity while imaging cadaver eyes (Post-mortem iris decomposition and its dynamics in morgue conditions. ArXiv pre-print, 2019).     

The effect of sodium hydroxide and hydrochloric acid on pig dermis. A light microscopic study

In order to compare the dermal changes after exposure to direct current (d.c.) with changes after influence of acid and base influence, the skin of fully anaesthetized Danish Landrace pigs were exposed to acid and basic solutions. Biopsies were obtained immediately after and up to day 7 after the injury. Collagen fibres with increased affinity for eosin and irregular cross-striation in polarized light together with shrunken cells with dark stained nuclei were found just beneath the epidermis immediately after application of 1 N HCl. Immediately after exposure to 1 N NaOH dispersed collagen fibres showed increased eosinophilia and a fine densely spaced cross-striation in polarized light and vesicular nuclei were present within dermal cells. During the following days a narrow demarcation zone of neutrophilic granulocytes separated the zone containing abnormal collagen fibres from normal tissue below. Calcified collagen fibres were not observed and no other abnormal histochemical reactions were present. It is concluded that the morphology of acid induced lesions and base induced lesions shows resemblance to the morphology of anode and cathode lesions, respectively, but not to heat lesions. The reason for not finding depositions of calcium salts on collagen fibres in skin exposed to basic solutions could be a non-optimal pH in the tissue or that other electrochemical processes than shift in pH are necessary for the calcification process.     

扫描电镜下缢沟的形态特征

作者用光镜和扫描电镜对縊沟进行对比观察,得出如下结论:(1)扫描电镜下縊沟组织的改变具有较恒定的特征,出血及纤维蛋白检出率远较光镜为高;(2)在光镜下生活反应不明显的生前缢沟,在扫描电镜下其表面及断面均可见红细胞及纤维蛋白形成,并包裹红细胞。縊沟部位胶原纤维之间可见散在大小不等的圆球形脂肪样小滴。缢沟部位肥大细胞的形态改变,有助于生前与死后缢沟的鉴别诊断。