Objective To evaluate CT and ultrasonic imaging as a diagnostic means of acute intestinal obstruction. Methods Acute intestinal obstruction of 30 patients diagnosed by preoperative CT scanning and ultrasonic imaging was retrospectively viewed, compaired with intraoperative and pathologic findings.Results The overall accuracy of CT for detection of obstruction was 86.7% (26/30),CT and ultrasonic imaging was 93.3% (28/30). Conclusion CT with ultrasonic imaging is of great advantages for senile patients especially having malignant tumors and for patients with intestinal intussuception. CT with ultrasonic imaging is found to be reliable for diagnosing ileolithiasis and abdominal abscess and mesentery vein thrombosis, but is less sensitive in cases of bowel torsion.
ObjectiveTo analyze the relationship between image development types and delay time in computed tomography urography (CTU) examination and to investigate the value of choosing reasonable delay time to get the best images. MethodWe collected the data of 62 patients who underwent multi-slice CTU examination without fully developed images within 8 minutes from January 2010 to May 2014. There were 35 unilateral and 27 bilateral delayed imaging patients with a total of 89 cases. According to the degree of imaging development after the delayed 8 minutes, we divided it into 4 levels as follows:level 0 (no development), levelⅠ (light development), levelⅡ (partial development) and levelⅢ (full development). LevelⅢ was not included in this study. For level 0 to levelⅡ, we delayed scan for 15 to 1 440 minutes. ResultsAs the imaging development degree decreased, the delay time obviously extended. LevelⅡ could be fully displayed after 15 to 150 minutes of delayed scan. LevelⅠ could be fully displayed after 150 to 720 minutes. Level 0 still had no imaging development after 120 minutes, so there was no need to continue scanning. ConclusionsSelecting appropriate delay time of CTU based on the type of delayed imaging development can avoid unnecessary repeated delay scans, get the best development images, and estimate the kidney secretion functions, which is most helpful for accurate diagnosis of urinary system related diseases.
Objective To explore the early diagnostic value of single photon emission computed tomography(SPECT), thoracic computed tomography(CT),and chest X-ray for closed chest trauma. Methods To establish the animal model of unilateral chest impact trauma,to adopt SPECT, thoracic CT, and chest X-ray for early diagnosis of closed chest trauma,and to compare these findings with postmortem examination. Results Thirty minutes after blunt chest trauma, the region of interesting (ROI) between traumatized lung and the heart (ROI2/ROI1) immediately increased to the peak six hours after trauma; on the contralateral lung, the ratio (ROI3/ROI1) increased slowly and reached the peak after six hours, these ratio was still smaller than that of the traumatized lung. These differences were significant (Plt;0.01). Conclusions Chest X-ray is still the most fundamental diagnostic method of chest trauma,but it was thought that the patients of severe chest trauma and multiple injuries should be examined early by thoracic CT. Radionuclide imaging have more diagnostic value than chest X-ray on pulmonary contusion. The diagnostic sensibility to pulmonary contusion of thoracic CT is superior to conventional radiograph,but thoracic CT is inferior to SPECT on exploring exudation and edema of pulmonary contusion. Thoracic CT is superior to conventional radiograph on diagnosis of chest trauma,therefore patients of severe chest trauma and multiple injuries should be adopted to thoracic CT examination at emergency room in order to be diagnosed as soon as possible.
ObjectiveTo discuss the CT imaging differences between mass-forming intrahepatic cholangiocarcinoma (ICC) and poorly-differentiated hepatocellular carcinoma (HCC). MethodThe clinical and CT data of 28 patients with mass-forming ICC (mass-forming ICC group) and 27 patients with poorly-differentiated HCC (poorly-differentiated HCC group), who were confirmed by pathological diagnosis in the West China Hospital from February 2014 to August 2014, were collected and analyzed retrospectively. ResultsThe contour, margin, enhancement patterns in the arterial phase and portal vein phase of the tumor had significant differences between the mass-forming ICC group and poorlydifferentiated HCC group (P < 0.05), in other words, the lobulated shape (15/28, 53.6%), indistinct margin (17/28, 60.7%), peripheral enhancement in the arterial phase (21/28, 75.0%) and prolonged enhancement in the portal vein phase (14/28, 50.0%) were more often seen in the mass-forming ICC group, while the poorly-differentiated HCC group were mainly the round shape (17/27, 63.0%), partially well-defined margin (18/27, 66.7%), diffuse heterogeneous enhancement in arterial phase (20/27, 74.1%) and wash out in the portal vein phase (18/27, 66.7%). The presence of bile duct dilatation in the the mass-forming ICC group was significantly higher than that in the poorly-differentiated HCC group﹝57.1% (16/28) versus 14.8% (4/27), P=0.001﹞. The size and enhancement degree of lymph node in the mass-forming ICC group were significantly bigger or higher than those in the poorly-differentiated HCC group (average lymph node size: 1.7 cm versus 1.3 cm, P=0.009; average enhancement degree of lymph node: 62.6 HU versus 51.8 HU, P=0.031). ConclusionCT features, such as tumor contour, margin, enhancement characteristics, the presence of bile duct dilatation, and the size and enhancement degree of lymph node, might help for differentiating mass-forming ICC from poorly-differentiated HCC, so that more timely selection of appropriate treatment strategies would be made.
Objective To evaluate the role of contrastenhanced CT (CECT) scanning in the diagnosis and treatment planning of some rare liver tumors. MethodsWe retrospectively reviewed the CECT imaging features of 10 cases with rare tumors of the liver proved by surgical pathology in 8 cases or by liver biopsy in 2 cases, with correlation of relevant clinical manifestations, laboratory results and surgical findings. ResultsThree cases were histopathologically proved to be benign, and 7 cases were malignant. On CT images, the liver lesions were mixed cysticsolid in 5 cases, totally solid in the other 5. Eight cases demonstrated heterogeneous enhancement, while 2 cases of liver lymphoma had no enhancement. The anatomic relationship of tumors to intrahepatic vasculature, the compression and infiltration of neighboring abdominal structures were accurately delineated by CT as compared with findings at operation. Clinical manifestations and laboratory findings were not useful for the qualitative diagnosis of rare liver tumors, except for hepatocellular carcinoma. ConclusionCECT is very useful for the detection of rare liver tumors and the fine depiction of local extent of these tumors. When correlated with clinical and laboratory information, it helps to differentiate rare liver tumors from hepatocellular carcinoma. But its role in the characterization of rare liver tumors is limited.
Objective We sought a good understanding of the current role of computed tomography (CT) in the diagnosis of small bowel obstruction (SBO).Methods We looked for the best evidence on computed tomography for diagnosing small bowel obstruction by searching MEDLINE/PubMed (1978-April, 2006), SUMsearch (1978-April, 2006), CNKI (1978-April, 2006) and critically appraised the evidence. Results There was powerful evidence supporting the efficacy of computed tomography in the diagnosis of small bowel obstruction. Given the current evidence together with our clinical experience and considering the patient and his family members, values and preferences, computed tomography was done. We confirmed the diagnosis of strangulating small bowel obstruction, which needed immediate operation. Conclusions Computed tomography is a very useful tool for the diagnosis of small bowel obstruction with high sensibility and specificity.
Objective To investigate the mult-slice spiral CT(MSCT)imaging manifestations of bowel wall thickening due to nontumorous causes,and to address the value of MSCT scanning in assessing nontumorous bowel wall thickening.MethodsThe MSCT findings of 284 patients with bowel wall thickening due to nontumorous causes confirmed by surgery,biopsy,or clinical follow-up were retrospectively analyzed.The location, range,symmetric or asymmetric,degree,attenuation,presence or absence of enhancement and associated perienteric abnormalities of thickened bowel wall were involved.ResultsAll nontumorous disease caused bowel wall thickening include liver cirrhosis(109 cases),acute pancreatitis(54 cases),bowel obstruction(36 cases),inflammatory bowel disease(14 cases),ischemic bowel disease(12 cases),radiation enterocolitis(13 cases),tuberculosis(12 cases),immune reaction(10 cases),infective enteritis(3 cases),acute appendicitis(3 cases),hypoproteinemia(5 cases),non-common disease(8 cases)and normal variants(5 cases).The attenuation pattern of the thickened bowel wall include high attenuation(1 case),iso-attenuation(144 cases),low attenuation(127 cases),fat deposition(5 cases)and pneumatosis(7 cases).The enhancement pattern of the thickened bowel wall included gentle enhancement(249 cases),notable enhancement(32 cases)and unenhancement(3 cases).Degree of bowel wall thickening included mild thinckening(279 cases)and marked thickening(5 cases).The range of bowel wall thickening was focal(8 cases),segmental(64 cases)and diffuse(212 cases).The associated perienteric abnormalities of thickened bowel wall included swelling of fat(218 cases),ascites(189 cases),lymphadenopathy(5 cases),peirenteirc abscess(2 cases),mesenteric vascular lesion(25 cases)and involvement of solid abdominal organs(169 cases). ConclusionMSCT has an invaluable role in the diagnostic evaluation of nontumorous bowel wall thickening.A wide variety of nontumorous diseases may manifest with bowel wall thickening at MSCT.Paying attention to the characteristics of thickening of bowel wall will benefit the diagnosis and differential diagnosis of various intestinal diseases.
The Monte Carlo N-Particle (MCNP) is often used to calculate the radiation dose during computed tomography (CT) scans. However, the physical calculation process of the model is complicated, the input file structure of the program is complex, and the three-dimensional (3D) display of the geometric model is not supported, so that the researchers cannot establish an accurate CT radiation system model, which affects the accuracy of the dose calculation results. Aiming at these two problems, this study designed a software that visualized CT modeling and automatically generated input files. In terms of model calculation, the theoretical basis was based on the integration of CT modeling improvement schemes of major researchers. For 3D model visualization, LabVIEW was used as the new development platform, constructive solid geometry (CSG) was used as the algorithm principle, and the introduction of editing of MCNP input files was used to visualize CT geometry modeling. Compared with a CT model established by a recent study, the root mean square error between the results simulated by this visual CT modeling software and the actual measurement was smaller. In conclusion, the proposed CT visualization modeling software can not only help researchers to obtain an accurate CT radiation system model, but also provide a new research idea for the geometric modeling visualization method of MCNP.
ObjectiveTo investigate the significance of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT in the diagnosis of primary hyperparathyroidism, and its relationship with the level of serum calcium (CA). MethodsThe clinical data of 73 patients with parathyroid dysfunction (serum parathyroid hormone (PTH) > 130 pg/mL) were retrospectively analyzed. The 99Tcm-MIBI SPECT double phase imaging were performed in 73 cases, 63 cases underwent cervical B-ultrasound examination, and 16 cases underwent CT examination. According to the serum calcium (CA) levels, the patients were divided into CA < 2.7 mmol/L group and CA > 2.7 mmol/L group, and the postoperative pathological examination and followed-up results were as the standard, the sensitivity, specificity, positive predictive value, and negative predictive value of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT for diagnosis of PHPT in different serum CA levels were compared. ResultsThe sensitivity of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT examination for diagnosis of PHPT was 87.6%, 81.8% and 35.7%, respectively; the specificity was 87.5%, 75.5% and 50.0%, respectively; the positive predictive value was 98.2%, 93.7% and 83.3%, respectively; and the negative predictive value was 46.7%, 33.3% and 10%, respectively. The sensitivity, specificity, positive predictive value and negative predictive value of 99Tcm-MIBI SPECT dual-phase imaging and B-ultrasound examination for diagnosis of PHPT were significantly higher than those of CT examination(P < 0.05). The sensitivity, specificity, positive predictive value and negative predictive value of 99Tcm-MIBI SPECT dual-phase imaging for diagnosis of PHPT were higher than those of B-ultrasound examination, but the difference was not statistically significant (P > 0.05). In the CA < 2.7 mmol/L group, the sensitivity of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT examination for diagnosis of PHPT was 91.1%, 84.7% and 37.9%, respectively; the specificity was 80.2%, 72.9% and 49.7%, respectively; the positive predictive value was 96.8%, 96.0% and 79.4%, respectively; and the negative predictive value was 50.0%, 37.5% and 10.0%. In the CA > 2.7 mmol/L group, The sensitivity of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT examination for diagnosis of PHPT was 87.9%, 83.9% and 42.8%, respectively; the specificity was 83.3%, 79.2% and 50.0%, respectively; the positive predictive value was 96.9%, 94.1% and 75.0%, respectively; and the negative predictive value was 50.0%, 40.5% and 20.0%. There were no significant difference in the diagnostic accuracy between the 3 methods and the level of serum CV in different levels. ConclusionsThe diagnostic accuracy of 99Tcm-MIBI SPECT dual-phase imaging and B-ultrasound examination for diagnosis of PHPT patients with PTH > 130 pg/mL (especially parathyroid adenoma) were higher than that of CT examination, and it is not associated with the serum CA concentration.
Objective To evaluate the imaging features of pancreatic neuroendocrine carcinoma （PNEC）. Methods The imaging data of 7 patients with PNECs proved by surgery and pathology in West China Hospital of Sichuan University from Jul. 2007 to Dec. 2012 were retrospectively analyzed. The boundary， density， and strengthening features of tumor were observed. Results Seven tumors were found in all patients with 2 in pancreatic head， body， and tail， respectively. There was 1 tumor in pancreatic body and tail too. Five tumors were with unclear boundary. Five tumors had hypodense enhancement and 2 had isodense enhancement. Two cases had distal pancreatic duct dilation. None of them had liver metastases or lymph node involvement. Conclusion PNEC has certain characteristics on imaging. It is difficult to distinguish diagnosis from pancreatic cancer.