Extrahepatic portacaval shunt via a magnetic compression technique: A cadaveric feasibility study

AIM: To explore the anatomical feasibility of portacaval shunt using a magnetic compression technique(MCT) in cadavers.METHODS: Computed tomography(CT) images of 30 portal hypertensive patients were obtained.The diameters of the portal vein(PV),the inferior vena cava(IVC),and distance between the two structures were measured.Similar measurements were performed on 20 adult corpses.The feasibility of portacaval shunt based on those measurements was analyzed.First stage of the extrahepatic portacaval shunt using MCT was performed on five cadavers.Specifically,the PV and IVC were exposed through an abdominal incision of the cadavers.The parent magnet was introduced from the femoral vein and was delivered into the IVC by an anchor wire and a 5F Cook catheter.The daughter magnet was introduced into the PV through the splenic vein using aninterventional guide wire.When the daughter magnet met the parent magnet,they automatically clipped together and the first stage of the portacaval shunt was set up.RESULTS: The average diameters of the PV and the IVC measured from the 30 CT image were 14.39 ± 2.36 mm and 18.59 ± 4.97 mm,respectively,and the maximum and minimum distances between the PV and the IVC were 9.79 ± 4.56 mm and 9.50 ± 4.79 mm,respectively.From 20 cadavers,the average diameters of the PV and the IVC were 14.48 ± 1.47 mm and 24.71 ± 2.64 mm,and the maximum and minimum distances between the PV and the IVC were 10.14 ± 1.70 mm and 8.93 ± 1.17 mm,respectively.The distances between the PV and the IVC from both the CT images and the cadavers were within the effective length of portacaval anastomosis using MCT(30.30 ± 4.19 mm).The PV and IVC are in close proximity to each other with no intervening tissues or structures in between.Simulated surgeries of the first stage using MCT on five cadavers was successfully performed.CONCLUSION: Anatomically,extrahepatic portacaval shunt employing MCT is highly feasible in humans.

3T magnetic resonance neurography of pudendal nerve with cadaveric dissection correlation

AIM: To evaluate the pudendal nerve segments that could be identified on magnetic resonance neurography(MRN) before and after surgical marking of different nerve segments.METHODS: The hypothesis for this study was that pudendal nerve and its branches would be more easily seen after the surgical nerve marking. Institutional board approval was obtained. One male and one female cadaver pelvis were obtained from the anatomy board and were scanned using 3 Tesla MRI scanner using MR neurography sequences. All possible pudendal nerve branches were identified. The cadavers were then sent to the autopsy lab and were surgically dissected by a peripheral nerve surgeon and an anatomist to identify the pudendal nerve branches. Radiological markers were placed along the course of the pudendal nerve and its branches. The cadavers were then closed and rescanned using the same MRN protocol as the premarking scan. The remaining pudendal nerve branches were attempted to be identified using the radiological markers. All scans were read by an experienced musculoskeletal radiologist.RESULTS: The pre-marking MR Neurography scans clearly showed the pudendal nerve at its exit from the lumbosacral plexus in the sciatic notch, at the level of the ischial spine and in the Alcock's Canal in both cadavers. Additionally, the right hemorrhoidal branch could be identified in the male pelvis cadaver. The perineal and distal genital branches could not be identified. On post-marking scans, the markers were used as identifiable structures. The location of the perineal branch, the hemorroidal branch and the dorsal nerve to penis(in male cadaver)/clitoris(in female cadaver) could be seen. However, the visualization of these branches was suboptimal. The contralateral corresponding nerves were poorly seen despite marking on the surgical side. The nerve was best seen on axial T1W and T2W SPAIR images. The proximal segment could be seen well on 3D DW PSIF sequence. T2W SPACE was not very useful in visualization of this small nerve or its branches.CONCLUSION: Proximal pudendal nerve is easily seen on MR neurography, however it is not possible to identify distal branches of the pudendal nerve even after surgical marking.

Prevalence and characteristics of gallstone disease in an Iranian population:a study on cadavers

BACKGROUND:The prevalence of gallstones is low in Asians.In Iran,many factors influence the prevalence of this disease.The aim of this study was to determine the prevalence of gallbladder stones and their chemical characteristics in a population by the study of cadavers. METHODS:In this cross-sectional study,autopsies were performed on 253 cadavers of more than 13 years old.The cadavers were studied to determine the number,location of stone formation,chemical composition,dry weight,and mean diameter of stones in the gallbladder and common bile duct. RESULTS:The prevalence of gallstone disease in these cadavers was 6.3%(men 4.7%,women 8.6%,not significantly different,P=0.216).There was a positive relationship between the age and prevalence of gallstone disease(P=0.033).The most common stone compositions were cholesterol and oxalate.The mean diameter (P=0.0058)and dry weight(P<0.0001)of stones were higher in the gallbladder than in the common bile duct. Positive relations between the amount of oxalate and mean diameter,and between the amount of oxalate and mean dry weight of gallstones were found,but the relationship between the amount of cholesterol and mean diameter was inverse. CONCLUSIONS:The prevalence of gallstones differed among age groups.Diameter and dry weight of gallstones were dependent on location of stone formation and chemical composition.

Partial Least Squares Structural Equation Path Modelling Determined Predictors of Students Reported Human Cadaver Dissection Activity

Human cadaver dissection remains a core and preferred method of anatomical instruction at most low- and middle-income health professional training institutions. Dissection, which is both traumatic and stressful, sets the tone of the students’ responses to later and or similar stressful learning opportunities like the post-mortems or care for terminally ill patients. Partial least squares structural equation modelling was used to determine the effect of the students’: personality, perception of the learning environment, learning approach, and effect of the environment on the student, on undergraduate health professional student’s activity in the human cadaver dissection room. This was a secondary analysis of previously collected data from a cross sectional survey of undergraduate health professional students. We found that personality type and perception of the environment had a positive effect on dissection room activity. Approach to learning and being affected by the dissection room experience (impact), had a negative effect on dissection room activity. All the above effects on dissection room activity were not significant. This study showed that personality, perception of the learning environment, learning approach and effect of the environment on the student, had effects on undergraduate health professional student’s activity in the human cadaver dissection room. The modelled effects are opportunities for educational interventions aimed at increasing student activity in the dissection room.

Cross-Over Assessment of the AmbuAuraGain, LMA Supreme New Cuff and Intersurgical I-Gel in Fresh Cadavers

Background: The AmbuAuraGain is a new single-use supraglottic airway device with gastric channel designed to facilitate intubation. The aim of the study was to assess the anatomic position and the performance of the AuraGain in fresh cadavers compared to that of the Intersurgical i-gel and LMA Supreme New Cuff. Methods: The 3 devices were inserted in random order in 7 fresh cadavers without difficult airway criteria. The assessed items were: Insertion time, number of attempts and ease of insertion, airway seal pressure, ease of gastric tube insertion, endoscopic view of vocal cords, efficacy of guided tracheal intubation through the AuraGain and i-gel, and anatomic fit by lateral X-ray and neck dissections. Results: All devices were successfully inserted within 3 attempts, except for one case of the LMA Supreme. Adjusting manoeuvres were often required to accomplish correct insertion. A 16 G gastric tube was easily advanced through all AuraGain and LMA Supreme devices. Fiberoptic tracheal intubation was effectively achieved through all AuraGain and i-gel devices in less than 60 s. Lateral X-ray and neck dissections confirmed optimal alignment of all devices with the respiratory and digestive tracts. Conclusions: Insertion of the new AmbuAuraGain required adjusting manoeuvres in some cases, as observed with the other two devices, and achieved similar airway seal pressures. Passage of a large bore gastric tube was as fast as with the LMA Supreme and ease of guided intubation was similar to that of the i-gel.

The Evaluation of Visual Cadavers in Medical Laboratory: from Teaching to Practical Applications

Visual Cadavers is anemerging study method which promotes medical education and practical applications.It is benefited from other techniques and evaluated as having huge advantages,which is not only accelerating teaching and learning,but also improving scientific study,nevertheless,with limited cons.

Pre-fabricated radial forearm phalloplasty with cadaveric bone graft

Phalloplasty is a complex set of procedures used in efforts to improve the anatomical,physiological,and aesthetic deficiencies caused by loss or absence of the penis.Methods have evolved significantly,and the use of free tissue transfer has become common amongst reconstructive surgeons.The inclusion of bone autograft,usually radius or fibula,within the neophallus has caused significant morbidity,and efforts continue to find the optimal solution.We present a novel approach using a pre-fabricated,radial forearm fasciocutaneous free flap containing cadaveric bone graft for phalloplasty following traumatic penis amputation.

Improving the Evaluation and Management of Cystotomy in Gynecologic Surgery with a Cadaver Surgical Curriculum

Objectives: Urinary tract injuries are a known complication of gynecologic surgery, occurring in 0.18% - 0.80% of procedures and most commonly involving the bladder. Appropriate identification, evaluation, treatment, and follow-up by gynecologic surgeons are important to reduce the associated long-term morbidities. The purpose of this study was to implement a comprehensive cadaver curriculum in cystotomy repair for OBGYN residents. Methods: This was a prospective observational cohort study including 10 OBGYN residents (PGY1-3) at a single institution in 2020 (56% of the 18 eligible residents). The curriculum consisted of a one-hour didactic lecture and one-hour hands-on surgical skills training with fresh frozen cadavers. Residents were evaluated in three domains: 1) knowledge, 2) surgical skills, and 3) confidence. Knowledge, confidence, and resident satisfaction were evaluated with pre- and post-surveys. The bladder model, derived from the ACOG Simulation Working Group, was used to evaluate surgical skills at baseline and at completion of the curriculum. Results: Across all three PGY levels, statistically significant improvements were observed in knowledge, surgical skills, and confidence after didactic and cadaver education (p = 0.001, p < 0.02, and p = 0.009 respectively). The largest increases in confidence occurred in residents’ ability to describe and perform cystotomy repairs. Conclusions: Educating and training OBGYN residents to manage and repair cystotomies can be challenging given the low incidence of injury in the operating room. The cadaver surgical skills curriculum was an effective training module and remains an important component of skills training in conjunction with simulation and traditional didactic sessions.

Complications of Learning Curve in Supratentorial Intraventricular Region. The Concept of Fast Daily Fresh Cadaver Practice. (Technical Note for Training Method)

Background: The difficulty of learning curve in different microsurgical regions is one of the most challenging factors that affect neurosurgeon’s life. Two of the delicate areas are the suprasellar intraventricular and pontocerebellar region. High level of microsurgery or endoscopic surgery requires virtuosity, which can not be learnt only by assisting. Even among the well skilled neurosurgeons who work in big centers we can often hear “in spite of centralization there are not enough operations available to keep the high level of our skills”. The situation of surgeons working at mid centers is more difficult especially on duties. Methods: Huge number of scientific articles demonstrate the importance of different types of cadaver practice, but always did not pay enough attention to the daily fast fresh cadaver exercises. Focusing on lifelong every day practice we examined the difficulties of learning curve in intraventricular and pontocerebellar region and try to give some useful advice for practicing on fresh cadavers on a daily basis. We offer a simple endovascular fresh cadaver model for practicing. Results: We have performed more than 800 quick (60 - 90 minutes long) routine practice sessions in these two regions during last 18 years. We found that implantation a modelized pathology and removing it by microscopical or endoscopic way without causing injuries to sensitive structures seems to be the most practical way of fast everyday training. Nerves and vascular bypass sutures are also excellent practical method. Conclusions: We have focused on daily fast fresh cadaver practice as a novel training method like used in professional sport and art. After 18 years experience we can state that, for mastering the microsurgery of pontocerebellar and intraventricular region, which is one of the most challenging regions minimum 100 fresh cadaver practice sessions need before performing the operation. We believe this region should be part of fast fresh cadaver microsurgical practice routine programme on daily bases, minimum one time/week/person.

Role of Fresh Cadaver Practice and Jesus Prayers on Daily Base in Innovations of a Difficult Neurosurgical Operation (Craniopagus Separation)

Purpose: Challenging cases in neurosurgery require experience, which is gained by operating on a number of similarly difficult cases. However, even in large population centers, there are extremely rare cases, such as craniopagus twins. In these instances, other case-specific solutions are required which were improved in the course of fresh cadaver practice on daily base. Methods: During a 20-month preparation period by fresh cadavers the surgical strategy was developed step by step, comprising five neurosurgical ideas, facilitated by deep Jesus prayers as a spiritual source. Possible causes of postoperative complications that occured on 33d postoperative day were also analyzed. Results: During surgery, these nuances proved to be useful, which is also reflected by the postoperative clinical results. One of the twins advanced to a GOS score of 5three months after the surgery. The other twin, despite nonsurgical septic complications, continued to progress well, but on postoperative day 33 for seemingly unknown reasons, she suffered a severe cerebral hemorrhage, which significantly delayed her rehabilitation. A thorough revision of the whole process much later revealed a pitfall that could have a role in this complication. Conclusions: The challenging neurosurgical separation of the craniopagus twins was carried out successfully with the help of five novel neurosurgical refinements, which were found during 300 fresh cadaver practices. Mistakes can serve as a lesson. We hope that the procedures developed and the knowledge gained can be applied in the future.

Nervous mechanisms of restraint water-immersion stress-induced gastric mucosal lesion

Stress-induced gastric mucosal lesion(SGML)is one of the most common visceral complications after trauma.Exploring the nervous mechanisms of SGML has become a research hotspot.Restraint water-immersion stress(RWIS)can induce GML and has been widely used to elucidate the nervous mechanisms of SGML.It is believed that RWIS-induced GML is mainly caused by the enhanced activity of vagal parasympathetic nerves.Many central nuclei,such as the dorsal motor nucleus of the vagus,nucleus of the solitary tract,supraoptic nucleus and paraventricular nucleus of the hypothalamus,mediodorsal nucleus of the thalamus,central nucleus of the amygdala and medial prefrontal cortex,are involved in the formation of SGML in varying degrees.Neurotransmitters/neuromodulators,such as nitric oxide,hydrogen sulfide,vasoactive intestinal peptide,calcitonin gene-related peptide,substance P,enkephalin,5-hydroxytryptamine,acetylcholine,catecholamine,glutamate,γ-aminobutyric acid,oxytocin and arginine vasopressin,can participate in the regulation of stress.However,inconsistent and even contradictory results have been obtained regarding the actual roles of each nucleus in the nervous mechanism of RWIS-induced GML,such as the involvement of different nuclei with the time of RWIS,the different levels of involvement of the sub-regions of the same nucleus,and the diverse signalling molecules,remain to be further elucidated.

Hydrogen sulfide attenuates gastric mucosal injury induced by restraint water-immersion stress via activation of KATPchannel and NF-κB dependent pathway

AIMTo explore the effect of hydrogen sulfide (H2S) on restraint water-immersion stress (RWIS)-induced gastric lesions in rats and the influence of adenosine triphosphate (ATP)-sensitive potassium (KATP) channels and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway on such an effect.METHODSMale Wistar rats were randomly divided into a control group, a physiological saline (PS) group, a sodium hydrosulfide (NaHS) group, a glibenclamide (Gl) group, Gl plus NaHS group, a pyrrolidine dithiocarbamate (PDTC) group, and a PDTC plus NaHS group. Gastric mucosal injury was induced by RWIS for 3 h in rats, and gastric mucosal damage was analyzed after that. The PS, NaHS (100 μmol/kg body weight), Gl (100 μmol/kg body weight), Gl (100 μmol/kg or 150 μmol/kg body weight) plus NaHS (100 μmol/kg body weight), PDTC (100 μmol/kg body weight), and PDTC (100 μmol/kg body weight) plus NaHS (100 μmol/kg body weight) were respectively injected intravenously before RWIS.RESULTSRWIS induced serious gastric lesions in the rats in the PS pretreatment group. The pretreatment of NaHS (a H2S donor) significantly reduced the damage induced by RWIS. The gastric protective effect of the NaHS during RWIS was attenuated by PDTC, an NF-κB inhibitor, and also by glibenclamide, an ATP-sensitive potassium channel blocker, in a dose-dependent manner.CONCLUSIONThese results suggest that exogenous H2S plays a protective role against RWIS injury in rats, possibly through modulation of KATP channel opening and the NF-κB dependent pathway.

A Case of Multiple Hemorrhagic Gastric Ulcers Developed via a Mechanism Similar to Water-Immersion Restraint Stress

In rats, water-immersion restraint stress is a model of experimental ulceration. We encountered a case in which multiple hemorrhagic gastric ulcers formed in the stomach in a setting similar to water-immersion restraint stress. The patient was a 54-year-old man who was found wet on a riverbank and transported by ambulance. Because of hypothermia and renal failure, hemodialysis was performed. Tarry stools were noted and endoscopy revealed the presence of multiple hemorrhagic gastric ulcers;thus, hemostasis was performed end oscopically. During the course, pseudo membranous colitis also developed and was ameliorated with vancomycin. Further, the renal failure and gastric ulcers improved, and the patient was discharged from hospital 25 days later. The reason why he survived more than 2 weeks was the hot summer season and he was not soaked in the river water throughout.

内镜下“沉船”减压技术治疗胸椎后纵韧带骨化症——基于尸体标本的技术报道

目的:建立尸体标本的胸椎后纵韧带骨化(ossification of posterior longitudinal ligament,OPLL)模型,探究在模型上进行内镜下OPLL“沉船”减压技术(sink boat technique,SBT)的可行性。方法:采用新鲜冰冻尸体标本,在导航机器人定位和CT引导下,从侧方经胸腔按术前规划路径穿刺T9椎体后缘。穿刺到达椎体后缘中份后,推注骨水泥并使之沿后纵韧带渗透到椎管内,CT扫描确认骨水泥渗入椎管并分布在T9椎体后方即认为模拟OPLL制备成功。采用内镜下SBT,从一侧椎间孔和对侧部分椎弓根入路进入椎体,从两侧向中心磨除部分椎体,直至双侧贯通,形成凹槽状椎体后缘的缺损,能够容纳模拟的OPLL。使用带线锚钉,将OPLL骨块锚定下沉并固定在椎体凹槽内,以达到椎管腹侧减压的目的。结果:我们成功在尸体标本上制备了胸椎OPLL的骨水泥模型,T9椎体后缘模拟OPLL椎管侵占率达49%。内镜下SBT手术顺利完成了胸脊髓腹侧的减压,术后CT证实模拟的OPLL通过内镜下SBT技术成功沉入并固定在椎体内,椎管矢状径恢复率达218%。结论:内镜下SBT是一种创新的胸椎内镜手术方法,在尸体上可以将模拟的节段性胸椎OPLL沉入椎体内达到椎管减压的目的。

广州市柠檬园柑橘木虱成虫和僵虫的发生动态及温湿度的关系

柑橘木虱Diaphorina citri是为害柑橘类嫩梢期的重要害虫之一,同时还是柑橘黄龙病自然传播的媒介昆虫。昆虫病原真菌是一类能够侵染昆虫并在其体内繁殖最终导致昆虫死亡的病原微生物,是害虫绿色防控的优质资源。为明确广州地区柠檬园柑橘木虱成虫和僵虫发生动态且精准指导该害虫的绿色防控,本研究利用五点取样调查法,持续1年对广州市柠檬园柑橘木虱成虫和僵虫发生动态进行监测。结果表明:柠檬园柑橘木虱成虫和僵虫的发生随月平均温度降低而逐渐减少;成虫发生高峰期为6-8月,僵虫发生率高峰期为8-10月,且柑橘木虱成虫和僵虫虫口密度与温度呈显著正相关。本监测结果不仅对柑橘木虱成虫的预测预报提供了理论基础,还有助于为柑橘木虱的科学管理和精准绿色防控提供了依据。

Water-assisted colonoscopy in inflammatory bowel diseases:From technical implications to diagnostic and therapeutic potentials

Water-assisted colonoscopy(WAC)application in inflammatory bowel diseases(IBD)endoscopy offers significant technical opportunities.Traditional gas-aided insufflation colonoscopy increases patient discomfort,presenting challenges in the frequent and detailed mucosal assessments required for IBD endoscopy.WAC techniques,including water immersion and exchange,provide superior patient comfort and enhanced endoscopic visualisation.WAC effectively reduces procedural pain,enhances bowel cleanliness,and increases adenoma detection rates,which is crucial for colorectal cancer screening and disease-related evaluations in IBD patients.Additionally,underwater techniques facilitate basic and advanced endoscopic resections,such as polypectomy and endoscopic mucosal and submucosal resections,often required for resecting IBD-associated neoplasia.

医学院校开展器官捐献相关教学探索

中国器官捐献试点工作开展后,遗体器官捐献事业在早期得到了快速发展。然而,自2018年起,我国器官捐献案例数进入平台期,甚至出现负增长,捐献供体短缺和人民群众对移植服务的需求之间的矛盾仍然较为严峻。医学生是未来中国医疗服务的中流砥柱,他们对器官捐献的认知度与接受度直接关系着我国器官捐献事业的发展。第二附属医院2022年开始,由移植医学研究所在中国率先针对研究生及本科生开展器官捐献教学,并取得了满意的效果。本研究总结了前期开设器官捐献教学方法的经验,探索了中国器官捐献教育模式,以期为促进中国器官捐献事业的高质量发展做出贡献。

尊重人体尸体:人体解剖教学的伦理原则

通过对医学院校解剖教学的调研和对利害关系人的访谈,发现不尊重人体尸体的观念和行为是阻碍遗体捐献的一个重要原因。因此提出“尊重人体尸体”这一解剖教学伦理原则,并加强对医学生解剖教学伦理教育。

石家庄地区夏秋季常见嗜尸性昆虫群落演替规律

目的研究石家庄地区常见嗜尸性昆虫种类及其群落演替。方法观察法研究2007—2009年夏秋季放置在同一地点的9只家兔尸体上常见嗜尸性昆虫的种群演替。结果该地区家兔尸体上出现常见双翅目3科4属9种,主要有蝇科的家蝇、厩腐蝇、开普黑蝇、厚环黑蝇;丽蝇科的丝光绿蝇、大头金蝇,麻蝇科的棕尾别麻蝇、肥须亚麻蝇、黑尾黑麻蝇。鞘翅目5科11种,主要有埋葬甲科的大黑葬甲、Silpha carinata(Herbst)、大负葬甲、Ptomascopus morio(Kraatz)、双色葬甲;蜣螂科的金龟子;步甲科的毛婪步甲和蠋步甲;拟步甲科的细土潜;隐翅甲科的大黑隐翅虫、小隐翅虫。膜翅目2科2种,蚁科的路舍蚁;胡蜂科的墨胸胡蜂。结论该地区嗜尸性蝇类群落演替明显,嗜尸性昆虫有地域特征。研究结果可作为石家庄地区对尸体进行死亡时间推断的依据。

亲属活体肾移植受者119例临床总结

目的回顾总结亲属活体肾移植受者围手术期的临床特点。方法收集119例亲属活体肾移植受者对照同期234例尸体肾移植受者,比较两组供肾热、冷缺血时间、供肾血管长度、植肾手术时间、术后平均住院时间、供受者HLA错配率、术后3d血肌酐下降速度、DGF发生率、急排发生率、1年人/肾存活率。结果亲属活体肾移植组供肾血管长度、供肾热、冷缺血时间、术后平均住院时间、HLA六位点法错配率、DGF、急排发生率均明显小于尸体肾移植组(P<0.01),而手术时间、术后3d血清肌酐下降速度、1年人/肾存活率亲属活体肾移植组均明显大于尸体肾移植组(P<0.01)。结论亲属活体肾移植的近期临床疗效明显优于尸体肾移植,远期(>1年)的临床效果比较有待进一步追踪观察。在有条件、技术成熟的移植中心亲属活体肾移植是患者家族内自救互救的重要途径。