多普勒微血管探头在三脑室底造瘘术中的应用

目的:探讨在治疗脑积水的内镜三脑室底造瘘术(endoscopic third ventriculostomy, ETV)中,应用多普勒微血管探头作超声检查的意义。方法:单纯神经内镜下完成梗阻性脑积水三脑室底造瘘术34例,其中21例应用多普勒微血管探头经内镜通道抵达三脑室底部进行超声探测,监测基底动脉(BA)的走向、血流速度,进行术中实时定位,造瘘前后记录血管的多普勒超声图像。结果:术后21例(61.76%)影像学证实扩大的脑室术后有回缩;半年后症状缓解29例(85.29%),无效5例(14.71%),2例做脑室-腹腔分流术。无手术死亡或残疾。使用探头组造瘘术前后BA的管径、血流速度无变化,无血管损伤并发症。结论:多普勒微血管探头在神经内镜三脑室底造瘘术中应用,可减少血管损伤类并发症的发生,使得内镜插入定位精确、安全。     

腔内超声在输尿管中下段结石的诊断价值探讨

目的探讨腔内超声（经直肠或阴道超声）在输尿管中下段结合的诊断价值。方法对临床疑诊为尿路结石的患者，按常规搜查肾脏和输尿管中上段，当发现肾盂扩张并排队了输尿管中上段落石后，改为腔内超声检查，确定是否有输尿管中下段结石，并对结果进行比较分析。结果经腔内超声对输尿管中下段结石的显示率较高。结论应用腔内超声诊断输尿管中下段结石快捷、方便、准确率高，具有较高的临床应用价值及鉴别诊断意义，价值推广。     

Preliminary study of contrast-enhanced harmonic endosonography with second-generation contrast agents

Purpose We developed a novel echoendoscope that enables contrast harmonic imaging using ultrasound contrast agents and performed contrast-enhanced harmonic endosonography (EUS) both in vitro and in vivo. Methods An experimental convex-array echoendoscope equipped with a wideband transducer and a specific mode for contrast harmonic imaging was used. A Doppler phantom model was employed in in vitro experiments to determine the optimal mechanical indices for contrast harmonic imaging by the echoendoscope. In the in vivo experiments, the echoendoscope was inserted into the stomachs of dogs. The digestive organs were observed after intravenous infusion of a contrast agent, Definity, using contrast-enhanced harmonic EUS. Two patients, one with pancreatic carcinoma and one with a gastrointestinal stromal tumor (GIST), underwent contrast-enhanced harmonic EUS. Results In vitro experiments revealed that the optimal mechanical indices were 0.35–0.40 for intermittent imaging and 0.30 or less for real-time imaging. In the in vivo experiments, branching vessels and subsequent homogeneous distribution of the signal in the pancreatic tissue were observed. During clinical application, typical vascular patterns were observed in pancreatic carcinoma and a GIST. Conclusion Contrast-enhanced harmonic EUS visualized parenchymal perfusion and the fine vascular structure in digestive organs and should be a useful and powerful method for clinical investigations.     

Contrast-enhanced endosonography for the diagnosis of anal and anovaginal fistulas

PURPOSE: We assessed whether contrast-enhanced anal endosonography (AES) with hydrogen peroxide improves the identification of anal fistulas and their internal openings compared with non-contrast AES. METHODS: The study group comprised 12 patients who had various types of anal fistulas with visible external openings. AES was performed before and about 15 seconds after injection of 1 ml of 3% hydrogen peroxide into the fistula tract through the external opening. RESULTS: Both contrast and non-contrast AES revealed 7 transsphincteric, 2 intersphincteric, 1 suprasphincteric, and 2 anovaginal fistulas. Simple tracts were found in 8 cases and complex tracts in 4 cases on non-contrast AES. Contrast-enhanced AES revealed 9 simple and 3 complex fistulas. One fistula that appeared complex on the non-contrast study appeared simple after contrast agent administration. Contrast-enhanced AES demonstrated more internal openings than non-contrast AES did. Surgery confirmed 11 of the fistulas; an internal opening could not be located surgically for the other tract. CONCLUSIONS: Contrast-enhanced AES appears to be superior to non-contrast AES in the preoperative assessment of anal and anovaginal fistulas and in demonstrating and locating their internal openings.     

超声内镜引导下细针穿刺对上消化道邻近组织肿瘤的诊断价值

目的探讨纵轴超声内镜引导下细针穿刺活检(EUS-FNA)对诊断上消化道邻近组织肿瘤的价值。方法26例上消化道邻近组织可疑肿瘤患者行纵轴EUS-FNA,进行细胞学及组织学检查与经手术病理最终诊断结果相比较,评价纵轴EUS-FNA诊断准确性及安全性。结果22例患者获得足够的细胞或组织学资料,穿刺成功率84.6%。在所有穿刺病例中,EUS-FNA敏感性84.0%,特异性100%;而在穿刺成功的病例中,敏感性达到95.5%,特异性100%。所有患者未出现严重并发症。结论纵轴EUS-FNA对诊断上消化道邻近组织肿瘤特异性高,是安全、有效的方法。     

Endoscopic ultrasound: moving from diagnostics to therapeutics

Endoscopic ultrasound was initially introduced in the 1980s as a diagnostic modality using echoendoscopes with radial scanning that permitted reconstruction of cross-sectional images similar to computed tomography The close proximity of the ultrasound transducer to the gastrointestinal wall and retroperitoneal structures allowed a detailed examination that is not possible with cross-sectional imaging such as computed tomography and magnetic resonance imaging. It proved to be highly accurate and useful in the staging of gastrointestinal malignancies, as well as in characterizing the nature of subepithelial lesions and disorders of the pancreaticobiliary system. The introduction of linear echoendoscopes facilitated fine needle aspiration because, with linear scanning, it was able to trace the path of the tip of the needle during the puncture process. In addition to being very useful for tissue acquisition for diagnostic purposes, the principles behind endoscopic ultrasound-guided fine needle aspiration paved the way for the development of therapeutic endoscopic ultrasound. Substances could now be delivered by endoscopic ultrasound into targeted areas, an example being an endoscopic ultrasound-guided celiac plexus block and neurolysis. In addition, the endoscopic ultrasound-guided puncture of fluid collections, abscesses and obstructed biliary and pancreatic ductal systems facilitated the passage of guidewires, thus allowing therapeutic drainage procedures to be performed using the Seldinger technique. This review summarizes the diagnostic capability of endoscopic ultrasound and then moves on to elaborate in detail its therapeutic capability and potential.     

TRANSGASTRIC TRANSHEPATIC ENDOSONOGRAPHY‐GUIDED BILIARY DRAINAGE: HISTOLOGICAL ASSESSMENT OF ITS SINUS TRACT IN AN AUTOPSY CASE

Endosonography‐guided biliary drainage (ESBD) is gaining attention as a promising drainage technique for obstructive jaundice. However, histological changes resulting from ESBD have not been well understood. We had an opportunity to histologically investigate the influence of ESBD, established between the left hepatic duct and the stomach, on the relevant organs in an autopsy case with bile duct cancer extending from the pancreatic head to the hepatic hilum with duodenal invasion. Localized fibrous connective tissues were present around and along the sinus tract, including the connection between the surfaces of the left lobe of the liver and the gastric serosa, without hemorrhage, inflammatory changes, or cancer invasion. The inside of the ESBD stent was slightly stenotic at the intramural portion of the stomach due to proliferation of granulation tissue. No bile stasis or abscess was observed in the left lobe. These results are quite suggestive of the high safety and efficacy of ESBD with adequate performance.     

Lymph node staging in esophageal squamous cell carcinoma: A comparative study of endoscopic ultrasonography versus computed tomography

Background and Aim:  Endoscopic ultrasonography (EUS) is established as a standard approach for locoregional staging of esophageal cancer. However, only a few published studies have attempted to correlate the station of the abnormal lymph nodes detected by EUS with the definitive histology. We compared EUS and computed tomography (CT) in the initial staging of esophageal squamous cell carcinoma.
Methods:  Consecutive patients with esophageal cancer undergoing EUS were evaluated. EUS findings and patient data including histopatology were collected prospectively and analyzed retrospectively. Lymph node locations were divided into three groups; abdominal (A), paraesophageal (B), and thoracic paratracheal (C).
Results:  A total of 365 consecutive patients underwent EUS and 159 patients underwent esophagectomy without neoadjuvant chemotherapy. Thirty-eight patients were excluded (insufficient EUS, etc.), and 121 patients were enrolled. The overall accuracy of EUS was 64% (sensitivity 68%, specificity 58%, positive predictive value [PPV] 68%), CT was 51% (sensitivity 33%, specificity 75%, PPV 64%), and CT + EUS was 64% (sensitivity 74%, specificity 50%, PPV 66%). The accuracy of EUS was higher than CT in Groups A and C. Sensitivity of CT was lower than that of EUS alone and CT + EUS.
Conclusions:  This study has demonstrated that EUS is a more accurate technique than contrast-enhanced CT for detecting abnormal lymph nodes. Sensitivity of CT was lower than that of EUS alone and CT + EUS. But some metastatic lymph nodes in neck and abdominal fields are only detectable by CT. Therefore, both EUS and CT should be undertaken for routine examination prior to treatment of esophageal cancer.     

Pancreatic tuberculosis

Pancreatic tuberculosis is very rare, but recently, there has been a spurt in the number of reports on pancreatic involvement by tuberculosis. It closely mimics pancreatic cancer, and before the advent of better imaging modalities it was often detected as a histological surprise in patients resected for a presumed pancreatic malignancy. The usual presentation involves abdominal pain, loss of appetite and weight, jaundice which can be associated with cholestasis, fever and night sweats, palpable abdominal lump, and peripheral lymphadenopathy. Computed tomography (CT) of the abdomen is an important tool for evaluation of patients with pancreatic tuberculosis. This CT imaging yields valuable information about the size and nature of tubercular lesions along with the presence of ascites and lymphadenopathy. However, there are no distinctive features on CT that distinguish it from pancreatic carcinoma. Endoscopic ultrasound provides high resolution images of the pancreatic lesions as well as an opportunity to sample these lesions for cytological confirmation. The presence of granulomas is the most common finding on histological/cytological examination with the presence of acid fast bacilli being observed only in minority of patients. As there are no randomized or comparative studies on treatment of pancreatic tuberculosis it is usually treated like other forms of tuberculosis. Excellent cure rates are reported with standard anti tubercular therapy given for 6–12 months.     

Extra‐pancreatic necrosis alone: Contours of an emerging entity

Acute pancreatitis is of two morphologic types: interstitial edematous pancreatitis that is not associated with any tissue necrosis and necrotizing pancreatitis wherein the pancreatic parenchyma with or without varying amount of extra‐pancreatic tissue/fat undergoes necrosis. Necrotizing pancreatitis has a worse outcome compared with interstitial pancreatitis because of increased severity related to a heightened systemic response and cytokine storm associated with tissue necrosis. Increasingly, an entity of extra‐pancreatic necrosis (EPN) alone, wherein the pancreatic parenchyma is normal on an enhanced computed tomographic scan but the peri‐pancreatic tissues undergo necrosis, is being recognized. Available data suggest that the outcomes in patients with EPN alone are between the excellent prognosis of patients with interstitial and adverse prognosis of patients with necrotizing pancreatitis. The extent of EPN also seems to determine the outcome. This review summarizes the currently available literature on this entity and various radiological scores that have been suggested to determine the presence and stage of EPN.