ObjectiveTo investigate the CT presenting rate and features of gastric bare area (GBA, including the area posterior to GBA and the adipose tissue in the gastrophrenic ligament) without pathologic changes.MethodsThirty cases with superior peritoneal ascites, but without pathological involvement of GBA were included into the study to show the normal condition of GBA, including the presenting rate and CT features. We selected some cases with GBA invasion by inflammation or neoplasm to observe their CT features. ResultsAll cases with superior peritoneal ascites showed the GBA against the contrast of ascites with the presenting rate of 100%. The GBA appeared at the level of gastricesophageal conjunction and completely disappeared at the level of hepatoduodenal ligament and Winslow’s foramen. The maximum scope of GBA presented at the level of the sagital part of the left portal vein with mean right to left distance of （4.39±0.08）cm (3.8~5.7 cm) (distance between the left and right layer of the gastrophrenic ligament). In acute pancreatitis, the width of GBA increased, in which local hypodensity area could be seen. In gastric leiomyosarcoma invading GBA, the mass could not separate from the crus of the diaphragm. In lymphoma and metastasis invading GBA, the thickness of GBA increased and the density was heterogeneous, in which lymph nodes presenting as small nodes or fused mass. ConclusionThe results of this study show that it is helpful to use contrast enhanced spiral CT scanning to observe the change of GBA and to diagnose retroperitoneal abnormalities that involving GBA comprehensively and accurately.
肺栓塞( PE) 的确诊依赖于肺动脉的影像学检查。电子计算机断层扫描肺动脉造影( CTPA) 诊断PE 的敏感性和特异性高[ 1] , 而且该项检查是无创技术, 患者痛苦小, 并发症少, 已成为诊断PE 的一线技术[ 2,3] 。随着CT 仪器的不断升级和改进以及检查技术的不断研究, CT 在PE 中的应用不再仅限于PE 的定性诊断, 还用于肺动脉栓塞程度的量化、右心室改变的诊断、患者预后判断以及下肢深静脉血栓形成( DVT) 的诊断等。
Abstract： Objective To explore the diagnosis and treatment of descending necrotizing mediastinitis (DNM). Methods We retrospectively analyzed the records of eight DNM patients treated at Tangdu Hospital between 2006 and 2009 year. There were 7 males and 1 female aged from 21-98 years with a median age of 49.5 years. The diagnostic criteria included clinical manifestations, neck and chest CT scans, and bacteriological culture. Six of the patients had odontogenic infections and six had diabetes. Antibiotic treatment, incision drainage, and other symptomatic treatments were applied. Two patients received cervical incision drainage, five received thoracotomy, and one received video-assisted thoracoscopic surgery (VATS). Results After treatment, six patients recovered and two died of heart failure and neck vessel rupture. According to the bacterial culture, six patients presented mixed infections, and four of these presented mixed aerobic and anaerobic infections. The mean operation time was 75.6 minutes, the average volume of pus removed during the operation was 318.7 ml, and the average inpatient stay was 18 days. At six months follow-up, all six surviving patients showed improvements in quality of life. Conclusion The valid diagnosed criteria of DNM include history, sign, symptom, neck and chest CT scanning, and secretion culture.DNM mortality can be reduced by employing broad spectrum antibiotics early in treatment, individual surgical managements, and effective treatments for complicating illnesses.
Descending necrotizing mediastinitis （DNM）is a severe infection spreading from the cervical or odontoiatric region to the mediastinum through the anatomic cervical spaces. DNM is very rare but fatal. The course of the illness proceeds rapidly and the mortality rate is high. The pathogenic process is closely related to anatomical and physiological characteristic of cervix and mediastinum. The most valuable way for decreasing its high mortality rate is to give early diagnosis and treatments. Computed tomography(CT) scan is especially important method in early diagnosis.The early and enough use of broad spectrum antibiotics, individual surgical management based on neck and chest CT, such as clearing necrotic tissues,drainage and flushing are all effective methods to decrease mortality rate. Related management , such as department of stomatology, head and neck surgery, thoracic surgery,intensive care unit, and infectious department,should give cooperative therapy when necessary. At the same time, more attention should be paid to the patients who have some systemic disease such as diabetes mellitus and whose physical constitutions are very poor, which could lead to DNM and worsening. It can help to decrease the incidence rate of fatal complications and to increase cure rate.
【Abstract】 Objective To evaluate the detection and localization of obscure lower gastrointestinal bleeding by using SPECT/CT and intraoperative endoscopy. Methods Twenty-six cases of patients with obscure lower gastrointestinal bleeding were analyzed retrospectively. Results The positive detection rate of SPECT/CT was 88.5%. All 26 patients (100%) were identified the bleeding source by using intraoperative endoscopy. No recurrence was found during 1-24 months follow-up. Conclusion SPECT/CT examination should be chosen firstly for patients with obscure lower gastrointestinal bleeding in order to localize the bleeding site roughly. Intraoperative endoscopy can localize the bleeding site accurately in patients who undergoes operation.
The convolutional neural network (CNN) could be used on computer-aided diagnosis of lung tumor with positron emission tomography (PET)/computed tomography (CT), which can provide accurate quantitative analysis to compensate for visual inertia and defects in gray-scale sensitivity, and help doctors diagnose accurately. Firstly, parameter migration method is used to build three CNNs (CT-CNN, PET-CNN, and PET/CT-CNN) for lung tumor recognition in CT, PET, and PET/CT image, respectively. Then, we aimed at CT-CNN to obtain the appropriate model parameters for CNN training through analysis the influence of model parameters such as epochs, batchsize and image scale on recognition rate and training time. Finally, three single CNNs are used to construct ensemble CNN, and then lung tumor PET/CT recognition was completed through relative majority vote method and the performance between ensemble CNN and single CNN was compared. The experiment results show that the ensemble CNN is better than single CNN on computer-aided diagnosis of lung tumor.
At present, most of the bone xenograft for clinical application comes from bovine. In recent years, many studies have been done on the clinical application of porcine xenograft bone. The goal of this study was to evaluate the effect of canine mandibular defects reparation with antigen-extracted porcine cancellous bone by imaging examination. Four dogs’ bilateral mandibular defects were created, with one side repaired with autologous bone (set as control group) while the other side repaired with antigen-extracted porcine cancellous bone (set as experimental group). Titanium plates and titanium screws were used for fixation. Cone beam computed tomography (CBCT), computed tomography (CT), single-photon emission computed tomography (SPECT) were undertaken at week 12 and 24 postoperatively, and SPECT and CT images were fused. The results demonstrated that the remodeling of antigen-extracted porcine cancellous bone was slower than that of autologous bone, but it can still be used as scaffold for jaw defects. The results in this study provide a new choice for materials required for clinical reparation of jaw defects.
Objective To discuss the CT imaging differences between hepatic neuroendocrine neoplasms (NENs) and hepatocellular carcinoma (HCC). Methods The clinical and CT data of 42 patients with hepatic NENs (hepatic NENs group) and 49 patients with HCC (HCC group), who were confirmed by pathology in the West China Hospital of Sichuan University from June 2011 to June 2016, were collected and analyzed retrospectively. This study was based on whether the lesions were larger than 3 cm or not, then CT findings of hepatic NENs patients and HCC patients in different stratification were compared. Results When the lesions were less than 3 cm, the location, contour, and enhancement patterns in the portal vein phase of the tumor had significant differences between the hepatic NENs group and the HCC group (P<0.05), multiple liver lesions, the round shape, and prolonged enhancement in the portal vein phase were more often seen in the hepatic NENs group, but there was no significant on diameter of tumor, boundary of lesion, pseudocapsules, scan density, hypervascularity, enhancement degree in arterial phase, enhancement patterns in arterial phase, daughter foci at liver, retraction, neoplastic artery, arteriovenous invaded, portal vein tumor thrombus, diameter of lymph node, and enhancement degree of lymph node between the 2 groups (P>0.05). And when the lesions were greater than or equal to 3 cm, the location, contour, enhancement patterns in the portal vein phase of the tumor, pseudocapsule, neoplastic artery, and arteriovenous invaded had significant differences between the hepatic NENs group and the HCC group (P<0.05), these CT images were often seen in the hepatic NENs group, such as multiple liver lesions, the lobulated shape, the portal venous phase continuous strengthening, no pseudocapsule, no neoplastic artery, and no arteriovenous invaded, but there was no significant difference on the diameter of tumor, boundary of lesion, scan density, hypervascularity, enhancement degree in arterial phase, enhancement patterns in arterial phase, daughter foci at liver, retraction, portal vein tumor thrombus, diameter of lymph node, and enhancement degree of lymph node between the2 groups (P>0.05). Conclusions No matter whether the lesions’ size are larger than 3 cm or not, the location, contour, and enhancement patterns in the portal vein phase could help for differentiating hepatic NENs from HCC. When the lessions are larger than 3 cm, pseudocapsule, neoplastic artery, and arteriovenous invaded may be useful to differentiate.
Liver cancer is a common type of malignant tumor in digestive system. At present, computed tomography (CT) plays an important role in the diagnosis and treatment of liver cancer. Segmentation of tumor lesions based on CT is thus critical in clinical diagnosis and treatment. Due to the limitations of manual segmentation, such as inefficiency and subjectivity, the automatic and accurate segmentation based on advanced computational techniques is becoming more and more popular. In this review, we summarize the research progress of automatic segmentation of liver cancer lesions based on CT scans. By comparing and analyzing the results of experiments, this review evaluate various methods objectively, so that researchers in related fields can better understand the current research progress of liver cancer segmentation based on CT scans.