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21.
64层螺旋CT三联检查在急性胸痛诊断中的应用   总被引:13,自引:0,他引:13  
目的探讨64层螺旋CT(MSCT)三联检查显示急性胸痛患者肺动脉、胸主动脉和冠状动脉病变的能力及其临床应用价值。方法70例患者进行64层MSCT回顾性心电门控肺动脉、胸主动脉和冠状动脉联合检查。采用多平面重组(MPR)、最大密度投影(MIP)、曲面重组(CPR)及容积再现(VR)多种重组技术显示肺动脉、胸主动脉和冠状动脉,评价成像质量能否满足临床诊断需要。结果平均扫描时间(8.5±1.0)s,总对比剂用量100ml。肺动脉和主动脉增强后CT值均≥200HU者占95.7%(67/70);冠状动脉显影图像质量优的节段占85.8%(720/839),图像质量良的节段占8.6%(72/839),图像质量差的节段占5.6%(47/839)。共检出冠状动脉狭窄≥50%者20例,肺动脉栓塞2例,主动脉夹层2例。结论64层MSCT三联检查能够在8s左右1次扫描完成肺动脉、胸主动脉和冠状动脉检查,图像质量可以满足临床诊断需要,在急性胸痛病因诊断中具有很高的临床应用价值。  相似文献   
22.
Acute aortic dissection complicated with acute myocardial infarction (AMI) is the most fatal situation. We experienced the successful treatment for acute type A aortic dissection complicated with inferior AMI following aortic valve replacement (AVR). A 60-year-old man had had AVR for aortic regurgitation. Sixteen months after the AVR, he had a sudden onset of severe chest pain with complete atrioventricular block. Immediately, temporary pacing and cardiac catheterization were conducted, showing the occlusion of the right coronary artery due to acute type A aortic dissection. On his way to our hospital, direct current shock was conducted 3 times for ventricular fibrillation. We replaced the ascending aorta combined with coronary artery bypass grafting and the postoperative course was uneventful. The key to treat acute aortic dissection complicated with AMI is early accurate diagnosis, prompt temporary pacing for bradycardia, defibrillation for lethal arrhythmia and insertion of a perfusion catheter if possible. These preoperative hemodynamic stabilization gives us the chance to save these patients.  相似文献   
23.
Based upon detailed dissections of the lymphatic system in adult cadavers, the lymphatic drainage of the gallbladder was divided into three pathways: (1) The cholecystoretropancreatic pathway, which had two routes, one running spirally from the anterior surface of the common bile duct to the right rear, and the other running almost straight down from the posterior surface of the common bile duct. These routes converged at the principal retroportal node at the posterior surface of the head of the pancreas. (2) The cholecysto-celiac pathway; this was the route running to the left through the hepatoduodenal ligament to reach the celiac nodes. (3) The cholecysto-mesenteric pathway; this was the route running to the left in front of the portal vein to connect with the nodes at the superior mesenteric root. The cholecysto-retropancreatic pathway can be regarded as the main pathway, and the principal retroportal node appeared to be critical as the main terminal node in the visceral lymphatic system of the gallbladder. These three pathways converged with the abdomino-aortic lymph nodes near the left renal vein, and the nodes in the interaortico-caval space were considered to be of particular importance. Offprint requests to: M. Ito  相似文献   
24.
Lymph node (LN) metastases represent the most important negative prognostic factor in squamous cell carcinoma (SCC) of the oral cavity, even though controversies still exist regarding their management. The aim of this study was to retrospectively analyze our experience in surgical management of SCC of the oral cavity with particular focus on the prevalence and localization of lymph nodal metastases and recurrences. The clinical records of 89 consecutive patients treated from 1983 to 2002 by concomitant surgery on both the T and N sites, excluding those undergoing salvage surgery, were reviewed. A total of 119 neck dissections (ND) were performed. Survival outcomes were calculated by the Kaplan–Meier method, while univariate comparisons by the log-rank and non-parametric tests were performed between different groups of patients. Five-year overall and determinate survivals were 50 and 57%, respectively. LN metastases were observed in 52% (56% of these showing extracapsular spread) and their presence strongly correlated with determinate survival (p < 0.0001). The prevalence of clinical and occult nodal disease was not related to the pT status. Neck levels II (59%) and I (56%) were most frequently involved. Metastases to level IV accounted for 15% of positive LN, even though 28% of them turned out to be skip metastases. Five neck recurrences were observed, only one of which was salvaged by surgery. The high prevalence of clinical and occult LN metastases in this setting suggests that ND should be performed on a nearly routine basis, even for lesions with a low-T category and a cN0 neck. Moreover, ND should always encompass level IV due to the possibility of skip metastases, particularly in tumors involving the oral tongue. In patients with a cN+ neck, levels from I to V should be addressed, particularly in the presence of metastases at levels III and IV.  相似文献   
25.
26.
Acute thoracic aortic dissection has a high mortality if untreated, so the diagnosis must be rapidly made if mortality is to be lowered significantly. Multiple imaging techniques are often used. This retrospective study from 1988 to 1993 assesses the usefulness in diagnosis of chest X-rays, computed tomography (CT) scanning, aortography, magnetic resonance imaging (MRI), trans-thoracic (TTE) and trans-oesophageal (TOE) echocardiography. Forty-two patients with a final clinical diagnosis of dissection were studied. The diagnosis was confirmed in 16 (13 at surgery and three at autopsy). Three died with dissection given as the only cause for death. Chest X-ray abnormalities were seen in all 19 patients with surgery or death from dissection, with a widened mediastinum and/or dilated aorta being present in 17. In the group of 16 patients with surgery or autopsy proof, CT scans found dissections in 9 of 12 patients studied and correctly classified the type in only five. Aortography was performed in five, with accurate depiction of dissection and type in all. TTE found dissections in three of eight patients imaged by this method. MRI and TOE were performed each on two patients, with accurate depiction of dissection and type in each. Because of the relatively low sensitivity of CT scanning in defining aortic dissections Westmead Hospital is currently assessing the use of TOE as the prime imaging modality prior to surgical intervention.  相似文献   
27.
血管内覆膜支架置入治疗降主动脉夹层动脉瘤   总被引:12,自引:1,他引:11  
目的 :介绍血管内覆膜支架置入治疗降主动脉夹层动脉瘤的初步经验。材料与方法 :本组 6例 Debakey 型的慢性降主动脉夹层动脉瘤患者行血管内覆膜支架置入治疗。经股动脉将 Talent覆膜支架置于夹层动脉瘤裂口处 ,支架张开使覆膜支架固定于裂口附近的主动脉壁上将裂口封闭并阻断血流。结果 :6例病人均获得成功 ,手术和临床成功率 10 0 %。 1例患者术中出现内漏 ,置入第二枚支架后漏口封闭。平均随访 7个月 ,所有患者内膜裂口全部完全封闭 ,假腔内血栓形成无内漏 ,假腔均明显缩小。结论 :血管内覆膜支架置入治疗主动脉夹层动脉瘤具有安全可靠 ,患者术后恢复快的优点  相似文献   
28.
The surgical management in papillary thyroid cancer has been highly controversial. In the Department of Surgery (II), Kanazawa University Hospital, the surgical management especially for cervical lymph node metastases has changed since 1973 from a conservative approach to an aggressive one. In order to determine whether an aggressive approach is warranted, a retrospective multivariate analysis was carried out on 106 cases of papillary thyroid cancer. The patients have been followed for 10-28 years. Multivariate analysis was conducted following Cox's model. By this analysis, aggressive management appeared to have no impact on survival or relapse-free survival. However, age, sex, tumor size, and cervical lymphadenopathy were confirmed to be important prognostic factors in survival and/or relapse-free survival.  相似文献   
29.
Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors.  相似文献   
30.
To control intraoperative bleeding is an important key to successful endoscopic submucosal dissection. The distribution of submucosal vessels encountered during the procedure differ in places in the stomach and are roughly categorized into three groups: those located in the antrum, those in the lesser curvature, and those on the anteroposterior corpus wall which consists of oblique muscle layers. Therefore, knowledge of a suitable setting of diathermy and adjusted depth of dissection in the submucosal layer for each site is imperative. The combination of utilizing the distal attachment forced or swift coagulation (trimming with coagulation mode) have enable the treatment with an insulation tipped knife safer.  相似文献   
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