Percutaneous transhepatic intraportal biopsy using gastroscope biopsy forceps for diagnosis of a pancreatic neuroendocrine neoplasm:A case report

BACKGROUND Pancreatic neuroendocrine neoplasms(PNENs)are a rare group of neoplasms originating from the islets of the Langerhans.Portal vein tumor thrombosis has been reported in 33%of patients with PNENs.While the histopathological diagnosis of PNENs is usually based on percutaneous biopsy or endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA),these approaches may be impeded by gastric varices,poor access windows,or anatomically contiguous critical structures.Obtaining a pathological diagnosis using a gastroscope biopsy forceps via percutaneous transhepatic intravascular pathway is an innovative method that has rarely been reported.CASE SUMMARY A 72-year-old man was referred to our hospital for abdominal pain and melena.Abdominal contrast-enhanced magnetic resonance imaging revealed a wellenhanced tumor(size:2.4 cm×1.2 cm×1.2 cm)in the pancreatic tail with portal vein invasion.Traditional pathological diagnosis via EUS-FNA was not possible because of diffuse gastric varices.We performed a percutaneous transportal biopsy of the portal vein tumor thrombus using a gastroscope biopsy forceps.Histopathologic examination revealed a pancreatic neuroendocrine neoplasm(G2)with somatostatin receptors 2(+),allowing systemic treatment.CONCLUSION Intravascular biopsy using gastroscope biopsy forceps appears to be a safe and effective method for obtaining a histopathological diagnosis.Although welldesigned clinic trials are required to obtain more definitive evidence,this procedure may help improve the diagnosis of portal vein thrombosis and related diseases.

Use of disposable graduated biopsy forceps improves accuracy of polyp size measurements during endoscopy

AIM: To determine the accuracy of endoscopic polyp size measurements using disposable graduated biopsy forceps(DGBF). METHODS: Gradations accurate to 1 mm were assessed with the wire of disposable graduated biopsy forceps. When a polyp was noted, endoscopists determined the width of the polyp; then, the graduated biopsy forceps was inserted and the largest diameter of the tumor was measured. After excision, during surgery or endoscopy, the polyp was measured using the vernier caliper.RESULTS: One hundred and thirty-three colorectal polyps from 119 patients were studied. The mean diameter, by post-polypectomy measurement, was 0.92 ± 0.69 cm; 83 were < 1 cm, 36 were between 1 and 2 cm, and 14 were > 2 cm. The mean diameter, by visual estimation, was 1.15 ± 0.88 cm; compared to the actual size measured using vernier calipers, the difference was statistically significant. The mean diameter measured using the DGBF was 0.93 ± 0.68 cm; compared to the actual size measured using vernier calipers, this difference was not statistically significant. The ratio between the mean size estimated by visual estimation and the actual size was significantly different from that between the mean size estimated using the DGBF and the actual size(1.26 ± 0.30 vs 1.02 ± 0.11).CONCLUSION: The accuracy of polyp size estimation was low by visual assessment; however, it improved when the DGBF was used.

Endoscopic transpapillary brush cytology and forceps biopsy in patients with hilar cholangiocarcinoma

AIM: To evaluate the sensitivity of brush cytology and forceps biopsy in a homogeneous patient group with hilar cholangiocarcinoma.METHODS: Brush cytology and forceps biopsy were routinely performed in patients with suspected malignant biliary strictures. Fifty-eight consecutive patients undergoing endoscopic retrograde cholangio-pancreatography (ERCP) including forceps biopsy and brush cytology in patients with hilar cholangiocarcinoma between 1995-2005.RESULTS: Positive results for malignancy were obtained in 24/58 patients (41.4%) by brush cytology and in 31/58 patients (53.4%) by forceps biopsy. The combination of both techniques brush cytology and forceps biopsy resulted only in a minor increase in diagnostic sensitivity to 60.3% (35/58 patients). In 20/58 patients (34.5%), diagnosis were obtained by both positive cytology and positive histology, in 11/58 (19%) by positive histology (negative cytology) and only 4/58 patients (6.9%) were confirmed by positive cytology (negative histology).CONCLUSION: Brush cytology and forceps biopsy have only limited sensitivity for the diagnosis of malignant hilar tumors. In our eyes, additional diagnostic techniques should be evaluated and should become routine in patients with negative cytological and histological findings.

Removal of diminutive colorectal polyps: A prospective randomized clinical trial between cold snare polypectomy and hot forceps biopsy

AIM To compare the efficacy and safety of cold snare polypectomy(CSP) and hot forceps biopsy(HFB) for diminutive colorectal polyps.METHODS This prospective, randomized single-center clinical trial included consecutive patients ≥ 20 years of age with diminutive colorectal polyps 3-5 mm from December 2014 to October 2015. The primary outcome measures were en-bloc resection(endoscopic evaluation) and complete resection rates(pathological evaluation). The secondary outcome measures were the immediate bleeding or immediate perforation rate after polypectomy, delayed bleeding or delayed perforation rate after polypectomy, use of clipping for bleeding or perforation, and polyp retrieval rate. Prophylactic clipping after polyp removal wasn't routinely performed.RESULTS Two hundred eight patients were randomized into the CSP(102), HFB(106) and 283 polyps were evaluated(CSP: 148, HFB: 135). The en-bloc resection rate was significantly higher with CSP than with HFB [99.3%(147/148) vs 80.0%(108/135), P < 0.0001]. The complete resection rate was significantly higher with CSP than with HFB [80.4%(119/148) vs 47.4%(64/135), P < 0.0001]. The immediate bleeding rate was similar between the groups [8.6%(13/148) vs 8.1%(11/135), P = 1.000], and endoscopic hemostasis with hemoclips was successful in all cases. No cases of perforation or delayed bleeding occurred. The rate of severe tissue injury to the pathological specimen was higher HFB than CSP [52.6%(71/135) vs 1.3%(2/148), P < 0.0001]. Polyp retrieval failure was encountered CSP(7), HFB(2).CONCLUSION CSP is more effective than HFB for resecting diminutive polyps. Further long-term follow-up study is required.

Improved specimen adequacy using jumbo biopsy forceps in patients with Barrett's esophagus

AIM:To assess the sampling quality of four different forceps(three large capacity and one jumbo) in patients with Barrett's esophagus.METHODS:This was a prospective,single-blind study.A total of 37 patients with Barrett's esophagus were enrolled.Targeted or random biopsies with all four forceps were obtained from each patient using a diagnostic endoscope during a single endoscopy.The following forceps were tested:A:FB-220 K disposable large capacity;B:BI01-D3-23 reusable large capacity;C:GBF-02-23-180 disposable large capacity;and jumbo:disposable Radial Jaw 4 jumbo.The primary outcome measurement was specimen adequacy,defined as a well-oriented biopsy sample 2 mm or greater with the presence of muscularis mucosa.RESULTS:A total of 436 biopsy samples were analyzed.We found a significantly higher proportion of adequate biopsy samples with jumbo forceps(71%)(P < 0.001 vs forceps A:26%,forceps B:17%,and forceps C:18%).Biopsies with jumbo forceps had the largest diameter(median 2.4 mm)(P < 0.001 vs forceps A:2 mm,forceps B:1.6 mm,and forceps C:2mm).There was a trend for higher diagnostic yield per biopsy with jumbo forceps(forceps A:0.20,forceps B:0.22,forceps C:0.27,and jumbo:0.28).No complications related to specimen sampling were observed with any of the four tested forceps.CONCLUSION:Jumbo biopsy forceps,when used with a diagnostic endoscope,provide more adequate specimens as compared to large-capacity forceps in patients with Barrett's esophagus.

Evaluation of novel slim biopsy forceps for diagnosis of biliary strictures: Single-institutional study of consecutive 360 cases(with video)

AIM To evaluate the feasibility and reliability of endoscopic transpapillary bile duct biopsy for the diagnosis of biliary strictures.METHODS A total of 360 patients(241 men) who underwent endoscopic retrograde cholangiopancreatography for biliary strictures with biopsy from April 2012 to March 2016 at Tokyo Medical University Hospital were retrospectively reviewed. This study was approved by our Institutional Review Board(No. 3516). Informed consent was obtained from all individual participants included in this study. The biopsy specimens were obtained using a novel slim biopsy forceps(Radial Jaw 4P, Boston Scientific, Boston, MA, United States).RESULTS The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 69.6%, 100%, 100%, 59.1%, and 78.8%, respectively. The sensitivity was 75.6% in bile duct cancer, 64% in pancreatic cancer, 61.1% in gallbladder cancer, and 57.1% in metastasis. In bile duct cancer, a lower sensitivity was observed for perihilar bile duct stricture(68.7%) than for distal bile duct stricture(83.1%). In terms of the stricture lengths of pancreatic cancer, gallbladder cancer, and metastasis, a longer stenosis resulted in a better sensitivity. In particular, there was a significant difference between pancreatic cancer and gallbladder cancer(P < 0.05). One major complication was perforation of the extrahepatic bile duct with bile leakage. CONCLUSION Endoscopic transpapillary biopsy alone using novel slim biopsy forceps is feasible and reliable, but restrictive. Biopsy should be performed in consideration of the stricture level, stricture length, and cancer type.

Successful endoscopic fragmentation of large hardened fecaloma using jumbo forceps

We present a rare case of fecaloma, 7 cm in size, in the setting of systemic scleroderma. A colonoscopy revealed a giant brown fecaloma occupying the lumen of the colon and a colonic ulcer that was caused by the fecaloma. The surface of the fecaloma was hard, large and slippery, and fragmentation was not possible despite the use of various devices, including standard biopsy forceps, an injection needle, and a snare. However, jumbo forceps were able to shave the surface of the fecaloma and break it successfully by repeated biting for 6 h over 2 d. The ability of the jumbo forceps to collect large mucosal samples was also appropriate for achieving fragmentation of the giant fecaloma.

Fine-needle aspiration technique under endoscopic ultrasound guidance:A technical approach for RNA profiling of pancreatic neoplasms

BACKGROUND Early diagnosis of pancreatic ductal adenocarcinoma(PDAC)has been a longstanding challenge.The prognosis of patients with PDAC depends on the stage at diagnosis.It is necessary to identify biomarkers for the detection and differentiation of pancreatic tumors and optimize PDAC sample preparation procedures for DNA and RNA analysis.Most molecular studies are done using paraffin-embedded blocks;however,the integrity of DNA and RNA is often compromised in this format.Moreover,RNA isolated from human pancreatic tissue samples is generally of low quality,in part,because of the high concentration of endogenous pancreatic RNAse activity present.AIM To assess the potential of endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)to obtain specimens from pancreatic neoplasms for subsequent RNA molecular profiling,including next-generation sequencing(NGS).METHODS Thirty-four EUS-FNA samples were included in this study:PDAC(n=15),chronic pancreatitis(n=5),pancreatic cysts(n=14),mucinous cysts(mucinous cystic neoplasia/intraductal papillary mucinous neoplasia)n=7,serous cystic neoplasms n=5,and pseudocysts n=2.Cyst material consisted of cyst fluid and cyst wall samples obtained by through-the-needle biopsy(TTNB).Samples were stored at -80℃ until analysis.RNA purity(A260/230,A260/280 ratios),concentration,and integrity(RIN)were assessed.Real-time polymerase chain reaction was conducted on all samples,and small RNA libraries were prepared from solid mass samples.RESULTS RNA was successfully extracted from 29/34(85%)EUS-FNA samples:100% pancreatic adenocarcinoma samples,100% chronic pancreatitis samples,70% pancreatic fluid cyst samples,and 50%TTNB samples.The relative expression of GAPDH and HPRT were obtained for all successfully extracted RNA samples(n=29)including lowquality RNA specimens.Low concentration and nonoptimal RIN values(no less than 3)of RNA extracted from EUS-FNA samples did not prevent NGS library preparation.The suitability of cyst fluid samples for RNA profiling varied.The quality of RNA extracted from mucinous cyst fluid had a median RIN of 7.7(5.0-8.2),which was compatible with that from solid neoplasms[6.2(0-7.8)],whereas the quality of the RNA extracted from all fluids of serous cystic neoplasms and TTNB samples had a RIN of 0.CONCLUSION The results demonstrate the high potential of EUS-FNA material for RNA profiling of various pancreatic lesions,including low-quality RNA specimens.

Endobiliary biopsy

The differential diagnosis between benign and malignant biliary strictures is challenging and requires a multidisciplinary approach with the use of serum biomarkers,imaging techniques,and several modalities of endoscopic or percutaneous tissue sampling.The diagnosis of biliary strictures consists of laboratory markers,and invasive and non-invasive imaging examinations such as computed tomography(CT),contrast-enhanced magnetic resonance cholangiopancreatography,and endoscopic ultrasonography(EUS).Nevertheless,invasive imaging modalities combined with tissue sampling are usually required to confirm the diagnosis of suspected malignant biliary strictures,while pathological diagnosis is mandatory to decide the optimal therapeutic strategy.Although EUS-guided fine-needle aspiration biopsy is currently the standard procedure for tissue sampling of solid pancreatic mass lesions,its diagnostic value in intraductal infiltrating type of cholangiocarcinoma remains limited.Moreover,the“endobiliary approach”using novel slim biopsy forceps,transpapillary and percutaneous cholangioscopy,and intraductal ultrasound-guided biopsy,is gaining ground on traditional endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography endobiliary forceps biopsy.This review focuses on the available endobiliary techniques currently used to perform biliary strictures biopsy,comparing the diagnostic performance of endoscopic and percutaneous approaches.

经口胆道镜引导靶向活检与十二指肠镜下经乳头活检钳活检对胆管狭窄伴可疑胆管癌诊断效能比较

目的比较经口胆道镜引导靶向活检与十二指肠镜下经乳头活检钳活检对胆管狭窄伴可疑胆管癌的诊断效能。方法选择2018年4月至2021年4月南阳市中心医院收治的82例胆管狭窄疑似胆管癌患者为研究对象,患者均接受经口胆道镜引导靶向活检及十二指肠镜下经乳头活检钳活检。以术后病灶组织病理学检查结果及至少随访1 a以上诊断结果为最终诊断结果,比较2种活检方法对胆管癌的诊断效能,并评估2种活检方式的安全性。结果最终诊断结果显示,82例胆管狭窄疑似胆管癌患者中60例确诊为胆管癌;22例确诊为良性胆管狭窄,其中高位胆管狭窄10例,低位胆管狭窄12例。经口胆道镜引导靶向活检诊断为胆管癌53例,最终诊断为胆管癌50例;诊断为胆管狭窄29例,最终诊断为胆管癌10例。十二指肠镜下经乳头活检钳活检诊断为胆管癌42例,最终诊断为胆管癌32例;诊断为胆管狭窄40例,最终诊断为胆管癌28例。经口胆道镜引导靶向活检诊断胆管癌的灵敏度为83.33%,特异度为86.36%,准确度为84.15%,阳性预测值为94.34%,阴性预测值为65.52%;十二指肠镜下经乳头活检钳活检诊断胆管癌的灵敏度为53.33%,特异度为54.55%,准确度为53.66%,阳性预测值为76.19%,阴性预测值为30.00%;十二指肠镜下经乳头活检钳活检诊断胆管癌的灵敏度、特异度、准确度、阳性预测值及阴性预测值显著低于经口胆道镜引导靶向活检(χ^(2)=12.478、5.350、17.786、6.534、8.571,P<0.05)。2种活检方法均可导致患者血C-反应蛋白水平增高,但未导致患者发生胆管穿孔、肠穿孔等并发症及操作相关性死亡。结论与十二指肠镜下经乳头活检钳活检相比,经口胆道镜引导靶向活检对于胆管狭窄疑似胆管癌患者诊断效能更高,且较为安全。

输尿管镜钬激光与活检钳治疗结石性输尿管息肉的临床疗效比较

目的比较输尿管镜钬激光与活检钳治疗结石性输尿管息肉的临床疗效。方法选取2019年8月至2022年6月昆山市第二人民医院收治的78例结石性输尿管息肉患者作为研究对象,按照随机数字表法分为对照组和观察组,每组39例。对照组采用输尿管镜钬激光治疗,观察组采用输尿管镜下活检钳治疗。比较两组临床指标、恢复情况及并发症发生情况。结果观察组手术时间、术后住院时间、尿液转清时间、术中出血量等临床指标均低于对照组,差异有统计学意义(P<0.05)。术前,两组肾积水、输尿管狭窄情况比较,差异无统计学意义(P>0.05);术后7 d,两组肾积水、输尿管狭窄发生率均下降,且观察组低于对照组,差异有统计学意义(P<0.05)。术后7 d,观察组穿孔、尿外渗等并发症发生率低于对照组,差异有统计学意义(P<0.05)。结论采用输尿管活检钳治疗结石性输尿管息肉患者,对改善患者肾积水、息肉形态、输尿管狭窄有积极作用,具有显著疗效的同时可降低术后穿孔、尿外渗等并发症发生率。

肝癌合并肝静脉-下腔静脉-右心房癌栓介入诊疗1例

1临床资料患者,男,50岁。因“双下肢肿痛11 d”入院。11 d前无明显诱因出现双下肢肿痛,为凹陷性水肿。当地医院腹部超声提示肝硬化、肝实性结节、肝右静脉至下腔静脉内栓子。既往乙肝病史20余年。实验室检查:ALT 240 U/L,AST 192U/L,Alb 38.8 g/L,肌酐132μmol/L,AFP 4.52 ng/mL,CA12564.7 U/mL,余无明显异常。

胃黏膜病变内镜黏膜下剥离术后病理升级的相关因素分析

背景胃癌的早期诊断对患者预后至关重要,目前,内镜下钳夹活检(EFB)是胃癌诊断的重要手段。然而,据相关研究显示,EFB诊断与内镜黏膜下剥离术(ESD)术后病理诊断之间存在一定差异,导致患者病情被低估。陕北地区目前此相关研究较少。目的统计陕北地区5所医院因胃黏膜病变经ESD后的病理升级率,并分析病理升级的相关因素。方法收集2016—2021年延安大学附属医院、延安市人民医院、榆林市第一医院、延安市中医院、子长市人民医院因胃黏膜病变行ESD治疗的患者,其术前均行EFB。本研究将病理类型分为:慢性炎性改变(CIC)、低级别上皮内瘤变(LGIN)、高级别上皮内瘤变(HGIN)、早期胃癌(EGC)及进展期胃癌。分析患者术前EFB诊断与ESD术后病理诊断的差异,将术后病理诊断发生升级者定义为病理升级。分别对术前EFB诊断为CIC、LGIN、HGIN患者ESD术后病理升级情况进行统计,并分析病理升级的相关因素。结果本研究共纳入241例患者。术前EFB诊断为CIC、LGIN、HGIN、EGC分别为84、75、65、17例。术前EFB诊断与ESD术后病理诊断总体升级率为31.5%(76/241)。多因素Logistic回归分析结果显示,内镜下分型[OR=0.134,95%CI(0.029,0.617)]和表面溃疡[OR=3.595,95%CI(1.226,10.536)]是术前EFB诊断为CIC患者ESD术后病理升级的影响因素(P<0.05);年龄[OR=3.961,95%CI(1.071,14.650)]、内镜下分型[OR=0.311,95%CI(0.127,0.765)]、表面发红[OR=5.830,95%CI(1.591,21.355)]及取材数目[OR=0.234,95%CI(0.063,0.872)]是术前EFB诊断为LGIN患者ESD术后病理升级的影响因素(P<0.05);病灶大小[OR=3.143,95%CI(1.003,9.852)]是术前EFB诊断为HGIN患者ESD术后病理升级的影响因素(P<0.05)。结论若术前活检提示为CIC,但内镜下分型为平坦型或凹陷型,病灶有表面溃疡,应警惕病理被低估的可能;术前活检提示为LGIN,但患者年龄>60岁、病灶为平坦型、病灶表面发红且取活检数目只有1块时,不排除术前病理被低估,必要时可行ESD;病灶大小>2 cm时,术前活检诊断HGIN的病灶很可能为EGC,建议行ESD。

清洗刷与活检钳模拟通过内镜钳子管道对其表面粗糙度及细菌黏附性的影响

目的分析两种器械对内镜钳子管道表面粗糙度(Ra)及细菌黏附性的影响。方法截取等长全新聚四氟乙烯(Teflon)管弯曲固定后,分别使用清洗刷(A组)、活检钳(B组)在不同通过次数下模拟临床操作,检测钳子管道Ra与表面形貌;将铜绿假单胞菌接种于各组Teflon管上,检测表面菌落形成单位与细菌黏附量。结果无器械通过的Teflon管表面光滑无划痕,随着通过次数增加,表面划痕逐渐密集,以清洗刷更明显。通过次数为0、50、100、200时,A、B两组间Ra比较,差异均无统计学意义;但通过次数为500时,两组间Ra比较,A组>B组(P<0.01)。两组内不同通过次数时的Ra比较,0次与50次相比,差异无统计学意义;但0次时的Ra均<100、200、500次的Ra,差异有统计学意义(P<0.01)。无器械通过的Teflon管表面生物膜分布均匀,随着通过次数增加,A组Teflon管表面生物膜覆盖较为紧密,且可见划痕处黏附的菌落。A、B两组间菌落计数在0、50、100、200次的情况下比较,差异无统计学意义;在500次的情况下,A组>B组(P<0.01)。A、B两组通过次数为50、100、200时的菌落数分别与通过次数为0时相比,差异无统计学意义(P>0.05);但通过次数为500时,A组的菌落数均值>0次(P<0.01),B组与0次比较,差异无统计学意义(P=0.186)。结论内镜清洗刷和活检钳反复通过钳子管道,均会增加内镜钳子管道的Ra,导致细菌黏附量增加,以清洗刷作用更为明显,提示临床应加强对器械的使用管理并研发更好的清洗工具。

热活检钳法与传统法经口内镜食管下括约肌切开术治疗贲门失弛缓症的疗效比较

目的 比较使用热活检钳的改良方法与使用三角刀的传统方法,在经口内镜食管下括约肌切开术(POEM)治疗贲门失弛缓症(AC)中的临床疗效。方法 前瞻性纳入2017年2月-2022年2月该院消化内科行POEM治疗的AC患者64例,随机分为热活检钳组和传统方法组,各32例,均行POEM。记录并比较两种手术方式的肌切开与隧道长度、术后住院时间、住院费用、手术时间和并发症发生情况。结果 两组患者均成功完成手术,两组患者手术肌切开长度、隧道长度、气体相关不良事件、住院时间、术后6个月胃食管反流率和术后3个月Eckardt评分比较,差异均无统计学意义(P> 0.05);但术中出血、手术时间、住院费用和术后6个月Eckardt评分比较,差异均有统计学意义(P <0.05)。结论 使用热活检钳法与传统法均能有效治疗AC,但热活检钳法能缩短手术时间,减少术中出血和住院费用,且长期疗效可能更显著,尤其适合在技术水平有限的临床机构中推广。

内镜下冷圈套器切除术与冷活检钳钳除术治疗结肠微小息肉的临床疗效比较

目的比较内镜下冷圈套器切除术(CSP)与冷活检钳钳除术(CBF)治疗结肠微小息肉的临床疗效。方法选取2018年1月至2022年1月在联勤保障部队第九八〇医院与河北省中医院经内镜检查确诊为结肠微小息肉的161例患者作为研究对象,按照治疗方法不同分为CSP组(80例,息肉数90枚)和CBF组(81例,息肉数93枚)。其中,CSP组采用CSP治疗,CBF组采用CBF治疗。比较两组手术指标(切除息肉时间、标本回收率和完整切除率)、炎症因子水平[白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)]水平变化,以及并发症(术中出血、术后出血、穿孔)发生情况、复发情况和新生息肉数。结果CSP组的切除息肉时间明显长于CBF组[(242±11)s比(226±12)s],完整切除率明显高于CBF组[97.78%(88/90)比90.32%(84/93)](P<0.01或P<0.05)。与术前相比,术后两组患者的血清IL-6、TNF-α水平均下降(P<0.05),但组间比较差异无统计学意义(P>0.05)。两组总并发症发生率比较差异无统计学意义(χ^(2)=1.198,P=0.274)。CSP组的复发率明显低于CBF组[26.25%(21/80)比41.98%(34/81)](P<0.05),但两组的新生息肉数比较差异无统计学意义(P>0.05)。结论与CBF相比,CSP完整切除率更高、复发率更低,不增加并发症发生率,但息肉切除时间更长。

胶囊机器人的柔顺钳设计与性能分析

针对胶囊机器人活检钳中零部件数量多、装配复杂的问题,提出了一种基于柔顺双稳态机构理论的柔顺钳。利用伪刚体模型对柔顺钳的双稳态特性进行理论分析,并设计有限元仿真与样机测试试验。在厚板夹持试验中,柔顺钳由开到闭切换,产生0.95 N的静态夹持力峰值,利于对组织破坏后夹取。通过有限元仿真模拟了不同铰链参数对柔顺钳双稳态特性的影响,其双稳态特性随着铰链厚度t的增大而先增大后减小直至消失。组织交互仿真试验中,柔顺钳有双稳态特性,组织所受最大等效应力在0.563~1.235 MPa范围;柔顺钳失去双稳态特性后,组织所受最大等效应力在0.230~0.403 MPa范围。该柔顺钳的结构简单,对组织有更大的破坏应力,为胶囊机器人活检提供新的思路。

活检钳钳除法治疗上消化道小息肉样病变56例

目的:探讨活检钳钳除法治疗上消化道小息肉样病变的疗效和安全性.方法:回顾性分析北京大学深圳医院2000-2009年电子胃镜检查发现上消化道小息肉样病变(直径≤0.5cm)并行活检钳钳除病例治疗和随访资料,并与同期高频电切除病例资料(病变直径≤2.0cm)对比,比较两种治疗方法的并发症和病变复发情况.结果:入选病例共91例.活检钳钳除组56例,单发息肉样病变48例,多发8例,共计68枚病变.高频电切除组35例,单发息肉样病变23例,多发12例,共计54枚病变.所有研究病例内镜治疗后均无上消化道出血、穿孔等并发症,两组并发症发生率均为0.0%,无显著性差异.半年以后的随访和胃镜复查中两组均各有1例复发,两组复发率分别为1.5%、1.9%,无显著性差异.结论:活检钳钳除法治疗上消化道小息肉样病变的疗效和并发症与高频电切除法相比无显著性差异.活检钳钳除法可彻底摘除上消化道小息肉样病变,临床疗效肯定,安全实用,是治疗上消化道小息肉样病变的有效手段.

布-加综合征下腔静脉阻塞区的介入放射学钳夹活检技术研究

目的 :探讨布 -加综合征下腔静脉阻塞区钳夹活检技术的可行性。方法 :采用钳夹活检技术对 12例布 -加综合征患者下腔静脉狭窄区进行钳夹活检并进行病理学分析。结果 :12例取得满意的组织块 ,1例假阳性 ,技术成功率10 0 % ,病理阳性率 91.7%。结论 :布 -加综合征下腔静脉阻塞区的钳夹活检技术容易操作 ,技术成功率高并且安全可靠 ,对揭示布 -加综合征的病因及发病机制具有重要价值。

圈套器冷切除与活检钳摘除结肠小息肉的疗效比较

目的探讨并比较圈套器冷切除与活检钳摘除结肠小息肉的疗效。方法选取行乙状结肠单发小息肉(息肉≤5 mm)治疗的患者,将其分为观察组(圈套器冷切除)和对照组(活检钳摘除)。观察2组患者的息肉完全切除率、切除时间及息肉切除后并发症(穿孔、出血)的发生率。结果共120例患者纳入研究,观察组和对照组各60例。观察组的完全切除率为100%,高于对照组的85%(P=0.003)。观察组的息肉切除时间为(74.8±5.4)s,对照组为(72.0±6.7)s,2组比较差异有统计学意义(P=0.014)。观察组和对照组的术后穿孔率均为0%,出血率分别为3%与0%,2组比较差异均无统计学意义(P均>0.05)。结论圈套器和活检钳均能安全有效地治疗结肠小息肉,使用圈套器冷切除的息肉完全切除率明显优于活检钳摘除。