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.
Manual segmentation of coronary arteries in computed tomography angiography (CTA) images is inefficient, and existing deep learning segmentation models often exhibit low accuracy on coronary artery images. Inspired by the Transformer architecture, this paper proposes a novel segmentation model, the double parallel encoder u-net with transformers (DUNETR). This network employed a dual-encoder design integrating Transformers and convolutional neural networks (CNNs). The Transformer encoder transformed three-dimensional (3D) coronary artery data into a one-dimensional (1D) sequential problem, effectively capturing global multi-scale feature information. Meanwhile, the CNN encoder extracted local features of the 3D coronary arteries. The complementary features extracted by the two encoders were fused through the noise reduction feature fusion (NRFF) module and passed to the decoder. Experimental results on a public dataset demonstrated that the proposed DUNETR model achieved a Dice similarity coefficient of 81.19% and a recall rate of 80.18%, representing improvements of 0.49% and 0.46%, respectively, over the next best model in comparative experiments. These results surpassed those of other conventional deep learning methods. The integration of Transformers and CNNs as dual encoders enables the extraction of rich feature information, significantly enhancing the effectiveness of 3D coronary artery segmentation. Additionally, this model provides a novel approach for segmenting other vascular structures.
CT texture analysis (CTTA) can objectively evaluate the heterogeneity of tissues and their lesions beyond the ability of subjective visual interpretation by extracting the texture features of CT images, then performing analysis and quantitative and objective evaluation, reflecting the tissue micro environmental information. This article reviews the recent studies on the applications of CTTA in gastric cancers, in the aspects of identification of gastric tumors, prediction of stage, correlation with Lauren classification, prediction of occult peritoneal carcinomatosis, evaluation of efficacy and prognosis, and prediction of biomarkers. It is regarded that CTTA has a good application prospect in gastric cancers.
Hemoptysis is a common respiratory emergency, and severe cases can lead to death. Patients with massive hemoptysis need emergency management at the bedside, and fully evaluation for indications and timing of tracheal intubation and transtracheal intervention. When a relatively stable state is achieved, emergency vascular intervention is performed to stop bleeding. CT plays an important role in the risk assessment and interventional treatment of hemoptysis, and it is worthy of clinical promotion and more exploratory research. This article introduces the emergency treatment for massive hemoptysis, the vascular interventional procedure, the exploration of clinical application of preoperative CT, and the clinical application value of CT for hemoptysis risk assessment. It aims to provide a better way to deal with massive hemoptysis and to apply CT to the interventional treatment of hemoptysis more reasonably for clinicians.
Objective To investigate the diagnostic value of CT scanning and MR imaging on acute cholecystitis. Methods The CT or MR imaging data of 21 patients with proved acute cholecystitis were retrospectively reviewed. Eleven patients were examined with contrast-enhanced multi-detector-row spiral CT scanning and other 10 cases underwent contrast-enhanced MR imaging. Results Nineteen patients showed obscure gallbladder outlines （90.5%）. The gallbladder wall demonstrated even thickening in 15 patients （71.4%） and irregular thickening in 6 cases （28.6%）. All patients showed inhomogeneous enhancement of the gallbladder wall （100%）. The bile was hyper-dense or hyper-intense on T1W image in 11 cases （52.4%）. Ten cases had free peri-cholecystic effusion （47.6%）, and 16 cases had peri-cholecystic adhesive changes or fat swelling （76.2%）. Patchy or linear-like transient enhancement of the adjacent hepatic bed in the arterial phase was seen in 16 cases （76.2%）. Twelve patients developed pleural effusion, or ascites, or both （57.1%）. Gallbladder perforation complicated with peritonitis was seen in one case, micro-abscess formation and pneumocholecystitis was observed in another case, and one case had gallbladder diverticulum. Conclusion Wall blurring, pericholecystic adhesion or fat edema, and transient enhancement of adjacent hepatic bed in the arterial phase are the imaging findings specifically associated with acute cholecystitis, which are readily appreciated on contrast-enhanced multi-phasic CT and MR scanning.
【Abstract】 Objective To review the study of noninvasive imaging methods for evaluating liver fibrosis. Methods The current literatures on the use of the ultrasonography， CT and MRI for the evaluation of liver fibrosis were reviewed. The principles, applications and advancement of each imaging methods were described and summarized respectively. The features of the newly developed imaging techniques were also discussed. Results In addition to the morphologic information， the imaging examinations can also provide functional information about the circulation status， diffusion and metabolism features of liver. The potential diagnostic value of MR elastography for liver fibrosis has been addressed. Conclusion The imaging examinations, especially the functional MRI techniques, are reliable noninvasive alternatives for the evaluation of hepatic fibrosis, with bright potentiality for clinical application.
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 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.
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.
Objective To evaluate the role of CT in diagnosis of the gastrointestinal tract rupture after blunt abdominal trauma. MethodsTwenty preoperative CT scans and clinical data were obtained in 20 patients who subsequently had bowel ruptures verified surgically. CT findings were analyzed retrospectively in these patients. Retrospective interpretation was made by consensus of at least two radiologists. ResultsTwenty cases of CT scan showed intraperitoneal fluid (18 cases), pneumoperitoneum (18 cases), extravasations of gastrointestinal tract contents (2 cases), bowel wall findings (14 cases) and mesenteric injury (15 cases). Conclusion CT is fast, sensitive and noninvasive in diagnosis of the gastrointestinal tract rupture after blunt abdominal trauma.