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.
Abstract： Objective To evaluate the diagnostic accuracy for the the assessment of coronary artery stenosesusing 64-multislice spiral computed tomography （64-MSCT） scanner compared with selective coronary angiography（SCA）. Methods 64-MSCT and SCA were both performed in 93 patients with 74 males and 19 females at mean age of （58.2±8.5） years in West China Hospital between April 2004 and December 2010. The cardiacrhythm of all the patients was stably sinus. Patients with initial heart rates≥90 time/min were received treatments of β-blockers. All available coronary segments（internal diameter ≥ 2.0 mm）were included in the evaluation. Lesions with ≥ 50％ luminalnarrowing were considered as significant stenosis. According to the image detail of segments and existance of artfacts,the image quality was randed Ⅰ to Ⅳ ,with rank Ⅰ to Ⅲ meeting demands of image evaluation. Evaluations had been done concerning the 64-MSCT scanner for detecting the stenosis of the variant branches or segments of the coronary artery. Results 64-MSCTprovided a full image correspondence(100%,1 238/1 238)of all the segments clearly displayed in the SCA. All of the coronary segments involved （n=1 238） met the quality demands of being evaluated as rankⅠ to Ⅲ. Considering SCA as the golden standard， overall sensitivity for classifying stenosis using 64-MSCT scannerwas 88.8%（427/481）， specificity was 91.7%（694/757）， positive predictive value was 87.1%（427/490），and negative predictive value was 92.8%（ 694/748）.While the stenosis diagnostic accuracy of proximal left circumflexbranch and the first obtuse marginal branch of left coronay artery is lower than other branches： the sensitivity of the proximal left circumflex branch was 68.3%（41/60），specificity was 60.6%（20/33），positive predictive value was 75.9%（41/54），negative predictive value was 51.3%（20/39）；the sensitivity of the first obtuse marginalbranch was 58.8%（10/17），specificity was 93.5%（58/62），positive predictive value was 71.4%（10/14），negative predictive value was 89.2%（58/65）. Arterial wall calcification and false image of cardiac movements were the maininfluence factors for accuracy of the the assessment of coronary artery stenosis with 64-MSCT scanner. Conclusion 64-MSCT scanner provids a high diagnostic accuracy in assessing stenosis of the coronary artery. The anatomical location and luminal area of coronary artery were the main influence factors of diagnostic accuracy. Thus the diagnostic accuracy in proximal left circumflex branch and the first obtuse marginal branch of left coronary artery was lower than other coronarysegments.
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.
Among numerous medical imaging modalities, diffusion weighted imaging (DWI) is extremely sensitive to acute ischemic stroke lesions, especially small infarcts. However, magnetic resonance imaging is time-consuming and expensive, and it is also prone to interference from metal implants. Therefore, the aim of this study is to design a medical image synthesis method based on generative adversarial network, Stroke-p2pHD, for synthesizing DWI images from computed tomography (CT). Stroke-p2pHD consisted of a generator that effectively fused local image features and global context information (Global_to_Local) and a multi-scale discriminator (M2Dis). Specifically, in the Global_to_Local generator, a fully convolutional Transformer (FCT) and a local attention module (LAM) were integrated to achieve the synthesis of detailed information such as textures and lesions in DWI images. In the M2Dis discriminator, a multi-scale convolutional network was adopted to perform the discrimination function of the input images. Meanwhile, an optimization balance with the Global_to_Local generator was ensured and the consistency of features in each layer of the M2Dis discriminator was constrained. In this study, the public Acute Ischemic Stroke Dataset (AISD) and the acute cerebral infarction dataset from Yantaishan Hospital were used to verify the performance of the Stroke-p2pHD model in synthesizing DWI based on CT. Compared with other methods, the Stroke-p2pHD model showed excellent quantitative results (mean-square error = 0.008, peak signal-to-noise ratio = 23.766, structural similarity = 0.743). At the same time, relevant experimental analyses such as computational efficiency verify that the Stroke-p2pHD model has great potential for clinical applications.
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.
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.
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.
【Abstract】ObjectiveBy using multidetector row spiral CT (MDCT) to investigate the CT imaging findings of gallbladder abnormalities caused by hepatic parenchymal diseases and those of inflammatory cholecystitis. MethodsCT and clinical data of 80 patients with gallbladder abnormalities were retrospectively reviewed. Fifty patients were in hepatic disease group, including 20 chronic hepatitis, 25 liver cirrhosis, and 5 cirrhosis with hepatocellular carcinoma. Thirty patients were in inflammatory group, including 19 chronic cholecystitis, 6 acute cholecystitis, 3 cholecystitis with acute pancreatitis, 1 gangrenous cholecystitis, and 1 xanthogranulomatous cholecystitis. All patients underwent MDCT plain scan and contrastenhanced dualphase scanning of upper abdomen. ResultsIn hepatic disease group, 48 cases had evenly thickened gallbladder wall (96%) with mean thickness of (3.67±0.49) mm; 38 cases had clear gallbladder outlines (76%); 38 cases had gallbladder wall enhancement of various degree (76%); 14 cases had gallbladder bed edema and localized nondependant pericholecystic fluid collection (28%). In inflammatory cholecystitis group, 28 cases had obscuring gallbladder outlines (93%) ; 26 cases had gallbladder wall evenly thickened (87%), 4 cases showed unevenly thicked wall (13%), the mean thickness being (4.54±1.14) mm; 30 cases had inhomogenous enhancement of the gallbladder wall (100%); 9 cases had highattenuation bile (30%); 4 cases had dependant pericholecystic fluid collection (13%); 5 cases had transient enhancement of adjacent hepatic bed in arterial phase (17%); microabscess and gas in the gallbladder wall was observed in 1 case respectively. ConclusionMDCT can offer imaging findings useful for differentiating abnormal gallbladder changes caused by hepatic parenchymal diseases from those due to inflammatory cholecystitis.
ObjectiveTo explore the clinical significance of quantitative CT measurement of pulmonary vascular indexes in chronic obstructive pulmonary disease (COPD). MethodsFifty-three stable COPD patients who were diagnosed in our hospital between May 2013 and February 2015 were recruited in the study. The HRCT results were analyzed, and the pulmonary vascular indexes were measured including the main pulmonary artery diameter (mPAD), axial diagonal mPAD, sagittal mPAD, right pulmonary artery diameter (RPAD), left pulmonary artery diameter (LPAD) and etc. The % CSA<5 (the percent of total cross-sectional area of the vascular with cross-sectional area less than 5 mm2 to total area of the lung) was calculated with Image J 1.48. The % LAA[volume percentage of low attenuation areas (<-950 HU)] representing degree of emphysema was calculated with GE ADW 4.5. Lung function test and questionnaires including CAT, mMRC, SGRQ and frequency of acute exacerbation of COPD (AECOPD) were completed and collected. ResultsIn COPD patients, the mPAD,axial diagonal mPAD, sagittal mPAD, RPAD and LPAD were positively correlated with % LAA respectively (r=0.36, 0.33, 0.43, 0.45, 0.33) and % CSA<5 was negatively correlated with % LAA (r=-0.37). mPAD was positively correlated with CAT, SGRQ and frequency of AECOPD respectively (r=0.52, 0.29, 0.35), and negatively correlated with FEV1% pred (r=-0.30).% CSA<5 was negatively correlated with CAT, SGRQ and frequency of AECOPD, respectively (r=-0.29,-0.30,-0.29), and positively correlated with FEV1% pred (r=0.28). The multivariate linear regression analysis revealed a linear relationship of mPAD with body mass index,% LAA and CAT. There was also linear relationships between axial diagonal mPAD, sagittal mPAD, RPAD and % LAA, CAT, respectively, and linear relationships between % CSA<5 and FEV1% pred,% LAA. The P value were all less than 0.05. ConclusionQuantitative CT measurement of cross-sectional area of small pulmonary vessels and pulmonary artery diameter are associated with clinical indexes in COPD patients, which will provide a new appraoche for the disease assessment of COPD patients.
Objective To summarize recent advances on preoperative staging strategies in rectal cancer. Methods Relevant references about preoperative staging strategies were collected and reviewed. The multimodal preoperative evaluation (MPE) system recently documented was focused on. Results The comparably accurate T and M stage could be achieved preoperatively by following an appropriate available method; however, the N stage’s accuracy was still not satisfying. The MPE system， incorporating with the advantages of transrectal ultrasound， computerized tomography and serum amyloid A protein in a multi-disciplinary mode could display the most accurate preoperative staging for rectal cancer currently. Conclusion The MPE has potential prospects in preoperative staging of rectal cancer， and can provide the most accurate preoperative staging for rectal cancer at present.
