Computed tomography colonography in 2014:An update on technique and indications

Twenty years after its introduction, computed tomographic colonography (CTC) has reached its maturity, and it can reasonably be considered the best radiological diagnostic test for imaging colorectal cancer (CRC) and polyps. This examination technique is less invasive than colonoscopy (CS), easy to perform, and standardized. Reduced bowel preparation and colonic distention using carbon dioxide favor patient compliance. Widespread implementation of a new image reconstruction algorithm has minimized radiation exposure, and the use of dedicated software with enhanced views has enabled easier image interpretation. Integration in the routine workflow of a computer-aided detection algorithm reduces perceptual errors, particularly for small polyps. Consolidated evidence from the literature shows that the diagnostic performances for the detection of CRC and large polyps in symptomatic and asymptomatic individuals are similar to CS and are largely superior to barium enema, the latter of which should be strongly discouraged. Favorable data regarding CTC performance open the possibility for many different indications, some of which are already supported by evidence-based data: incomplete, failed, or unfeasible CS; symptomatic, elderly, and frail patients; and investigation of diverticular disease. Other indications are still being debated and, thus, are recommended only if CS is unfeasible: the use of CTC in CRC screening and in surveillance after surgery for CRC or polypectomy. In order for CTC to be used appropriately, contraindications such as acute abdominal conditions (diverticulitis or the acute phase of inflammatory bowel diseases) and surveillance in patients with a long-standing history of ulcerative colitis or Crohn’s disease and in those with hereditary colonic syndromes should not be overlooked. This will maximize the benefits of the technique and minimize potential sources of frustration or disappointment for both referring clinicians and patients.

Splanchnic vein thrombosis in necrotizing acute pancreatitis: Detection by computed tomographic venography

AIM: To assess the diagnostic accuracy of computed tomographic venography(CTV) for splanchnic vein thrombosis(SVT) detection in necrotizing acute pancreatitis(AP) patients.METHODS:Forty-three patients with necrotizing AP who underwent both CTV and digital subtraction angiography(DSA)within 3 d were analyzed in this retrospective comparative study.All CTV procedures were performed with a dual-source CT scanner.The presence and location of SVT were determined via blinded imaging data analyses.RESULTS:According to the DSA results,17(39.5%)of the total 43 patients had SVT.The sensitivity,specificity,positive and negative predictive values of CTV for SVT detection were 100%(95%CI:77.1%-100%),92.3%(95%CI:73.4%-98.7%),89.5%(95%CI:65.5%-98.2%)and 100%(95%CI:82.8%-100%),respectively.CONCLUSION:CTV is an effective examination for SVT detection in patients with necrotizing AP with high positive and negative predictive values.

Evaluation of contrast-enhanced computed tomographic colonography in detection of local recurrent colorectal cancer

AIM： TO evaluate the diagnostic accuracy, sensitivity, specificity of contrast-enhanced computed tomographic colonography in detecting local recurrence of colorectal cancer. METHODS： From January 2000 to December 2004, 434 patients after potentially curative resection for invasive colorectal cancer were followed up for a period ranging from 20 to 55 mo. Eighty of the four hundred and thirty-four patients showing strong clinical evidence for recurring colorectal cancer during the last followup were enrolled in this study. Each patient underwent contrast-enhanced computed tomographic colonography and colonoscopy on the same day. Any lesions, biopsies, identified during the colonoscopic examination, immediate complications and the duration of the procedure were recorded. The results of contrast-enhanced computed tomographic colonography were evaluated by comparing to those of colonoscopy, surgical finding, and clinical follow-up. RESULTS： Contrast-enhanced computed tomographic colonography had a sensitivity of 100%, a specificity of 83% and an overall accuracy of 94% in detecting local recurrent colorectal cancer. CONCLUSION： Conventional colonoscopy and contrastenhanced tomographic colonography can complement each other in detecting local recurrence of colorectal cancer.

Computed tomographic colonography:Hope or hype?

Computed tomographic colonography (CTC) is a promising emerging technology for imaging of the colon. This concise review discusses the currently available data on CTC technique,test characteristics,acceptance,safety,cost-effectiveness,follow-up strategy,and extracolonic findings. In summary,CTC technique is still evolving,and further research is needed to clarify the role of automated colonic insufflation,smooth-muscle relaxants,intravenous and oral contrast,soft-ware rendering,and patient positioning. Currently,full bowel preparation is still required to achieve optimal results. The sensitivity for detecting large polyps (> 1 cm) can be as high as 85%,with specificity of up to 97%. These test characteristics are almost comparable to those of conventional colonoscopy. Patient acceptance of CTC is generally higher than that for colonoscopy,especially in patients who have never undergone either procedure. CTC is generally safe,although uncommon instances of colonic perforation have been documented. In terms of cost-effectiveness,most decision analyses have concluded that CTC would only be cost-effective if it were considerably cheaper than conventional colonoscopy. The proper follow-up strategy for small polyps or incidental extracolonic findings discovered during CTC is still under debate. At present,the exact clinical role of virtual colonoscopy still awaits determination. Even though widespread CTC screening is not available today,in the future there may eventually be a role for this technology. Technological advances in this area will undoubtedly continue,with multi-detector row CT scanners allowing thinner collimation and higher reso-lution images. Stool-tagging techniques are likely to evolve and may eventually allow for low-preparation CTC. Perceptual and fatigue-related reading errors can potentially be minimized with the help of computer-aided detection software. Further research will define the exact role of this promising technology in our diagnostic armamentarium.

Findings on intraprocedural non-contrast computed tomographic imaging following hepatic artery embolization are associated with development of contrast-induced nephropathy

BACKGROUND Contrast-induced nephropathy(CIN)is a reversible form of acute kidney injury that occurs within 48-72 h of exposure to intravascular contrast material.CIN is the third leading cause of hospital-acquired acute kidney injury and accounts for 12%of such cases.Risk factors for CIN development can be divided into patientand procedure-related.The former includes pre-existing chronic renal insufficiency and diabetes mellitus.The latter includes high contrast volume and repeated exposure over 72 h.The incidence of CIN is relatively low(up to 5%)in patients with intact renal function.However,in patients with known chronic renal insufficiency,the incidence can reach up to 27%.AIM To examine the association between renal enhancement pattern on non-contrast enhanced computed tomographic(CT)images obtained immediately following hepatic artery embolization with development of CIN.METHODS Retrospective review of all patients who underwent hepatic artery embolization between 01/2010 and 01/2011(n=162)was performed.Patients without intraprocedural CT imaging(n=51),combined embolization/ablation(n=6)and those with chronic kidney disease(n=21)were excluded.The study group comprised of 84 patients with 106 procedures.CIN was defined as 25%increase above baseline serum creatinine or absolute increase≥0.5 mg/dL within 72 h post-embolization.Post-embolization CT was reviewed for renal enhancement patterns and presence of renal artery calcifications.The association between noncontrast CT findings and CIN development was examined by Fisher’s Exact Test.RESULTS CIN occurred in 11/106(10.3%)procedures(Group A,n=10).The renal enhancement pattern in patients who did not experience CIN(Group B,n=74 with 95/106 procedures)was late excretory in 93/95(98%)and early excretory(EE)in 2/95(2%).However,in Group A,there was a significantly higher rate of EE pattern(6/11,55%)compared to late excretory pattern(5/11)(P<0.001).A significantly higher percentage of patients that developed CIN had renal artery calcifications(6/11 vs 20/95,55%vs 21%,P=0.02).CONCLUSION A hyperdense renal parenchyma relative to surrounding skeletal muscle(EE pattern)and presence of renal artery calcifications on immediate post-HAE noncontrast CT images in patients with low risk for CIN are independently associated with CIN development.

Feasibility of Subtraction Coronary Computed Tomographic Angiography and Influencing Factor Analysis: a Retrospective Study

Objective To investigate the feasibility of subtraction coronary computed tomographic(CT)angiography(SubCCTA)to decline calcium artifacts and improve diagnostic accuracy in the presence of coronary calcification and analyze the factors that influence SubCCTA.Methods A total of 294 patients suspected of having coronary artery diseases underwent coronary computed tomographic angiography(CCTA)and SubCCTA.Coronary stenoses were blindly evaluated by two experienced radiologists,which were compared with invasive coronary angiography(ICA).Multiple statistical indexes were adopted to analyze the value of SubCCTA for the diagnosis of calcium stenoses.Results The diagnosable rate of SubCCTA was 67.2%(n=197),and the non-diagnosable rate was 32.8%(n=97).Using SubCCTA,the false positive rate decreased from 56.5%to 17.4%,and the corresponding diagnostic accuracy was increased from 83.6%to 92.9%.Univariate logistic regression analysis showed that height(OR=1.029,95%CI=1.001–1.058),weight(OR=1.025,95%CI=1.004–1.046),left ventricular size(OR=1.018,95%CI=1.007–1.030),cardiothoracic ratio(OR=39.917,95%CI=1.244–1281.098),the average heart rate(OR=0.866,95%CI=0.836–0.896)and heart rate range(OR=0.882,95%CI=0.853–0.912)might be the factors influencing SubCCTA.Conclusion This study suggested that SubCCTA could help improve diagnostic accuracy in the presence of calcium plaques.Moreover,several factors were discovered for the first time to possibly influence SubCCTA,which will be helpful in improving the subtracted image quality.

Extracolonic findings of computed tomographic colonography in Koreans

AIM:To determine the frequency and characteristics of extracolonic lesions detected using computed tomographic(CT)colonography.METHODS:The significance of extracolonic lesions was classified as high,intermediate,or low.Medical records were reviewed to establish whether further investigations were carried out pertaining to the extracolonic lesions that were detected by CT colonography.RESULTS:A total of 920 cases from 7 university hospitals were included,and 692 extracolonic findings were found in 532(57.8%)patients.Of 692 extracolonic findings,60 lesions(8.7%)were highly significant,250(36.1%)were of intermediate significance,and 382(55.2%)were of low significance.CT colonography revealed fewer extracolonic findings in subjects who were without symptoms(P<0.001),younger(P<0.001),or who underwent CT colonography with no contrast enhancement(P=0.005).CT colonography with contrast enhancement showed higher cost-effectiveness in detecting highly significant extracolonic lesions in older subjects and in subjects with symptoms.CONCLUSION:Most of the extracolonic findings detected using CT colonography were of less significant lesions.The role of CT colonography would be optimized if this procedure was performed with contrast enhancement in symptomatic older subjects.

Serial computed tomographic findings and specific clinical features of pediatric COVID-19 pneumonia:A case report

BACKGROUND A series of recent cases of pneumonia in Wuhan,Hubei Province,China,was caused by the 2019 novel coronavirus[2019-nCoV,also called severe acute respiratory syndrome(SARS)-CoV-2].The World Health Organization officially named the disease as coronavirus disease 2019(COVID-19).With the global spread of COVID-19,similar cases have appeared in other areas of China,and there are a few reports of pediatric patients with COVID-19 pneumonia.CASE SUMMARY A 7-year-old girl was diagnosed with COVID-19 and presented with irregular fever,sore throat and diarrhea.Chest computed tomography revealed patchy consolidation and ground-glass opacities in multiple areas.The lesions were mainly distributed in the bronchial bundles or subpleural areas of both lungs,particularly in the right lower lobe.The patient also presented with diarrhea,mild kidney injury,and live coronavirus was found in her feces.She was given antiviral agents(lopinavir and ritonavir),and follow-up detection showed that these abnormalities were markedly decreased within 3 d.CONCLUSION The clinical symptoms and prognosis of COVID-19 in pediatric patients may be different from those in adult patients,and the fecal–oral transmission of SARSCoV-2 should be considered.

Numerical Simulation of Flow Behavior in Basilar Bifurcation Aneurysms Based on 4-Dimensional Computed Tomography Angiography

Initiation, growth, and rupture of cerebral aneurysms are caused by hemodynamic factors. It is extensively accepted that the cerebral aneurysm wall is assumed to be rigid using computational fluid dynamics (CFD). Furthermore, fluid-structure interactions have been recently applied for simulation of an elastic cerebral aneurysm model. Herein, we examined cerebral aneurysm hemodynamics in a realistic moving boundary deformation model based on 4-dimensional computed tomographic angiography (4D-CTA) obtained by high time-resolution using numerical simulation. The aneurysm of the realistic moving deformation model based on 4D-CTA at each phase was constructed. The effect of small wall deformation on hemodynamic characteristics might be interested. So, four hemodynamic factors (wall shear stress, wall shear stress divergence, oscillatory shear index and residual residence time) were determined from the numerical simulation, and their behaviors were assessed in the basilar bifurcation aneurysm.

Multi-scale characterizations of colon polyps via computed tomographic colonography

Texture features have played an essential role in the field of medical imaging for computer-aided diagnosis.The gray-level co-occurrence matrix(GLCM)-based texture descriptor has emerged to become one of the most successful feature sets for these applications.This study aims to increase the potential of these features by introducing multi-scale analysis into the construction of GLCM texture descriptor.In this study,we first introduce a new parameter-stride,to explore the definition of GLCM.Then we propose three multi-scaling GLCM models according to its three parameters,(1)learning model by multiple displacements,(2)learning model by multiple strides(LMS),and(3)learning model by multiple angles.These models increase the texture information by introducing more texture patterns and mitigate direction sparsity and dense sampling problems presented in the traditional Haralick model.To further analyze the three parameters,we test the three models by performing classification on a dataset of 63 large polyp masses obtained from computed tomography colonoscopy consisting of 32 adenocarcinomas and 31 benign adenomas.Finally,the proposed methods are compared to several typical GLCM-texture descriptors and one deep learning model.LMS obtains the highest performance and enhances the prediction power to 0.9450 with standard deviation 0.0285 by area under the curve of receiver operating characteristics score which is a significant improvement.

The value of three-dimensional computed tomographic angiography in the early diagnosis and treatment of spontaneous subarachnoid hemorrhage (616 cases report)

Objective To evaluate the clinical value of three dimensional computerized tomography angiography in the diagnosis and treatment of spontaneous subarachnoid hemorrhage. Methods 616 cases were diagnosed as suspected intracranial aneurysms in 3D CTA system. Computed tomographic scans and CTA studies were

Evaluation of recurrence in gastric carcinoma: Comparison of contrast-enhanced computed tomography and positron emission tomography/computed tomography

AIM To compare the value of contrast-enhanced abdominal computed tomography(CT) and fluorodeoxyglucose(FDG) positron emission tomography/computed tomography(PET/CT) for detecting gastric carcinoma recurrence.METHODS We retrospectively examined data from 2475 patients who underwent both contrast-enhanced abdominal CT and FDG PET/CT for the surveillance of gastric carcinoma curative resection. Patients had an interval of less than 1 mo between their CT and PET/CT scans. Sixty patients who had recurrence were enrolled. Among 1896 patients who did not have recurrence, 60 were selected by simple random sampling. All CT and PET/CT images were reviewed retrospectively by two reviewers blinded to all clinical and pathologic information except curative resection due to gastric carcinoma. RESULTS The pathological stage of the recurrence group was statistically significantly higher than that of the control group(P < 0.001). In the 60 patients who had recurrence, there were 79 recurrent lesions. Fortyfour patients had only one location of recurrence, 13 patients had two locations, and 3 patients had three. In the detection of patient-based overall recurrence, no statistically significant differences existed between the two modalities(P = 0.096). However, for peritoneal carcinomatosis, CT had a statistically significantly higher sensitivity compared to PET/CT(96% vs 50%, P = 0.001). Adenocarcinoma was the most common type of gastric carcinoma. On the pathology-based analysis, CT also had a statistically significantly higher sensitivity compared to PET/CT(98% vs 80%, P = 0.035).CONCLUSION Contrast-enhanced CT was superior to PET/CT in the detection of peritoneal carcinomatosis and pathologic type of adenocarcinoma.

Noninvasive three-dimensional computed tomographic angiography in preoperative detection of intracranial arteriovenous malformations

Obejctive To assess the value of noninvasive three dimensional computed tomographic angiography (3D CTA) in preoperative detection of intracranial arteriovenous malformations (AVMs) Methods A prospective evaluation at a single institute over a 2 year period included 23 patients suspected of intracranial AVMs All patients underwent 3D CTA and digital subtraction angiography (DSA) Results from both procedures were compared Results 3D CTA imaging provided excellent visualization of intracranial AVMs The false positive error and false negative error were zero in our sample The details of arterial supply (numerical measure, orientation, caliber and routing) and vascular nidus (size, morphosis and location) provided by 3D CTA images were the same as DSA and the details of venous drainage were an approximate match Additionally, 3D CTA can depict tridimensional anatomical information for AVMs and their relationship to adjacent structures, a function not possible with DSA This assisted the surgeons in making better surgical planning and reduced trauma As a non invasive course, there were no related complications in the course of 3D CTA processing Conclusions DSA is still regarded as the gold standard for intracranial AVMs detection The modality of 3D CTA is accurate, noninvasive, nearly risk free and low price; we could routinely use it instead of or as a supplement to DSA, in the preoperative detection of suspected intracranial AVMs and postoperative radiological follow up 3D CTA adds tridimensional aspect and assists the surgeon in a the more accurate therapeutic scheme Preliminary data suggest that 3D CTA is playing a favorable role in the assessment of patients with intracranial AVMs

Impact of Clinical Guideline Recommendations on the Application of Coronary Computed Tomographic Angiography in Patients with Suspected Stable Coronary Artery Disease

Background： Coronary computed tomographic angiography （CCTA） has been widely used in patients who are at intemaediate risk for having stable coronary artery disease （SCAD）, and 2013 European Society of Cardiology Guidelines on the Management of SCAD （2013G） recommended the appropriate application of CCTA. However, 2013G has not been subjected to systematic analyses for subsequent impact on clinical practice. Methods： A total of 5320 patients suspected with SCAD were enrolled and scheduled for CCTA from March 2013 to September 2014. For each patient, pretest probability of SCAD was calculated according to updated Diamond-Forrester model （UDFM）. Appropriate CCTA or appropriate stress test was determined as described in the 2013G. A generalized estimating equation model was used to determine the trends in the half-monthly rate of appropriate CCTA. Results： Overall, only 61.37% of patients received appropriate CCTA, and there was insignificant change over time （P = 0.8701）. The application of CCTA in patients who should have had a stress test accounted for most of the inappropriate CCTA before （22.29%） or after （19.98%） the publication of the 2013G. In all patients or any subgroup, no significant change in the adjusted half-monthly rate of appropriate CCTA was found after the publication of the 2013G （odds ratio, 1.002; 95% confidence interval, 0.982-1.021; P = 0.8678）. Conclusions： These findings suggest that the 2013G have not, to date, been fully incorporated into clinical practice, and the clinical utilization of CCTA remains unreasonable to some extent.

Angio-Computed Tomograph-Guided Immediate Lipiodol Computed Tomograph for Diagnosis of Small Hepatocellular Carcinoma Lesions during Transarterial Chemoembolization

Background： The diagnosis and treatment of small hepatocellular carcinoma （HCC） play a vital role in the prognosis of patients with HCC. The purpose of our study was to evaluate anglo-computed tomography （angio-CT）-guided immediate lipiodol CT （a CT scan performed immediately after transarterial chemoembolization [TACE]） in the diagnosis of potential HCCs ≤1 cm in diameter. Methods： This study retrospectively analyzed 31 patients diagnosed with HCCs after routine imaging （contrast-enhanced CT or magnetic resonance imaging） or pathologic examinations with undefined or undetermined tumor lesions （diameter 〈1 cm） from February 2016 to September 2016. After TACE guided by digital subtraction angiography of the angio-CT system, potential HCC lesions with a diameter ≤1 cm were diagnosed by immediate lipiodol CT. The number of well-demarcated lesions was recorded to calculate the true positive rate. The correlation between the number of small HCCs detected by immediate lipiodol CT and the size of HCC lesions （diameter 〉1 cm） diagnosed preoperatively was analyzed 1 month after TACE. A paired t-test was used to analyze differences in liver function. Pearson analysis was used to analyze correlation. Chi-square test was used to compare the rates. Results： Fifty-eight lesions were detected on preoperative routine imaging examinations in 31 patients including 15 lesions with a diameter ≤ 1 cm. Ninety-one lesions were detected on immediate lipiodol CT, of which 48 had a diameter ≤ 1 cm. After 1 month, CT showed that 45 lesions had lipiodol deposition and three lesions had lipiodol clearance. Correlation analysis showed that the number of small HCCs detected by lipiodol CT was positively correlated with the size of HCC lesions diagnosed by conventional imaging examination （R^2 - 0.54, P 〈 0.05）. Conclusion： Immediate lipiodol CT may be a useful tool in the diagnosis of potential HCC lesions with a diameter of ≤1 cm.

Identification of the distinguishing features of Crohn’s disease and ischemic colitis using computed tomographic enterography

Background and aims:The differential diagnosis between Crohn’s disease(CD)and ischemic colitis(ISC)is important as their clinical management is different.ISC can easily be misdiagnosed as CD,especially in elderly populations.The distinctive radiographic features of the two disease entities have not been investigated.The aim of this study is to assess the utility of computed tomographic enterography(CTE)in the differential diagnosis between CD and ISC.Methods:Patients with confirmed CD and ISC were identified through an electronic medical record search of the Cleveland Clinic Foundation.Patients who had undergone CTE,with or without concurrent colonoscopy and histopathological specimens,were included in this study.CTE images were blindly re-reviewed by an expert gastrointestinal radiologist.The sensitivities,specificities,accuracies and positive and negative predictive values for each of the CTE findings in differentiating CD from ISC were estimated.Kappa coefficients(j)were calculated tomeasure diagnosis agreement between CTE and the reference standard.Results:A total of 34 eligible patients were included in this study with 17 having CD and 17 having ISC.In differentiating CD from ISC,the presence ofmucosal hyperenhancement and absence of the“target sign”on CTE showed a sensitivity of 100% each for CD,while the two radiographic features yielded a low specificity of 35.3%and 76.5%,respectively.The presence of stricture had a lower sensitivity of 64.7% for the detection of CD but had a high specificity of 100%.In distinguishing CD fromISC,the accuracy of presence ofmucosal hyperenhancement,stricture and absence of target sign were 67.7%,82.4% and 88.2%,respectively.The combination of the presence ofmucosal hyperenhancement and the absence of the target sign achieved an accuracy of 100%for distinguishing CD from ISC.There was a good correlation between CTE and the reference standard for distinguishing CD fromISC(k=0.882).Conclusions:CTE appeared to be clinically useful in distinguishing CD from ISC.

Coronary Computed Tomographic Angiography for Suspected Stable Coronary Artery Disease： Gap Between the 2013 European Society of Cardiology Guideline Recommendations and Clinical Practice

Coronary computed tomographic angiography （CCTA） as a noninvasive diagnostic technique for the evaluation of coronary anatomy is widely used clinically. Its advantages include high sensitivity and specificity for the diagnosis of present of coronary artery lesions and lesion characteristics,

Understanding the predictive value and methods of risk assessment based on coronary computed tomographic angiography in populations with coronary artery disease:a review

Risk assessment in coronary artery disease plays an essential role in the early identification of high-risk patients.However,conventional invasive imaging procedures all require long intraprocedural times and high costs.The rapid development of coronary computed tomographic angiography(CCTA)and related image processing technology has facilitated the formulation of noninvasive approaches to perform comprehensive evaluations.Evidence has shown that CCTA has outstanding performance in identifying the degree of stenosis,plaque features,and functional reserve.Moreover,advancements in radiomics and machine learning allowmore comprehensive interpretations of CCTA images.This paper reviews conventional as well as novel diagnostic and risk assessment tools based on CCTA.

Intentionally unilateral prostatic artery embolization:Patient selection,technique and potential benefits

BACKGROUND Prostatic artery embolization(PAE)is a promising but also technically demanding interventional radiologic treatment for symptomatic benign prostatic hyperplasia.Many technical challenges in PAE are associated with the complex anatomy of prostatic arteries(PAs)and with the systematic attempts to catheterize the PAs of both pelvic sides.Long procedure times and high radiation doses are often the result of these attempts and are considered significant disadvantages of PAE.The authors hypothesized that,in selected patients,these disadvantages could be mitigated by intentionally embolizing PAs of only one pelvic side.AIM To describe the authors’approach for intentionally unilateral PAE(IU-PAE)and its potential benefits.METHODS This was a single-center retrospective study of patients treated with IU-PAE during a period of 2 years.IU-PAE was applied in patients with opacification of more than half of the contralateral prostatic lobe after angiography of the ipsilateral PA(subgroup A),or with markedly asymmetric prostatic enlargement,with the dominant prostatic lobe occupying at least two thirds of the entire gland(subgroup B).All patients treated with IU-PAE also fulfilled at least one of the following criteria:Severe tortuosity or severe atheromatosis of the pelvic arteries,non-visualization,or visualization of a tiny(<1 mm)contralateral PA on preprocedural computed tomographic angiography.Intraprocedural contrast-enhanced ultrasonography(iCEUS)was applied to monitor prostatic infarction.IU-PAE patients were compared to a control group treated with bilateral PAE.RESULTS IU-PAE was performed in a total 13 patients(subgroup A,n=7;subgroup B,n=6).Dose-area product,fluoroscopy time and operation time in the IU-PAE group(9767.8μGy∙m^(2),30.3 minutes,64.0 minutes,respectively)were significantly shorter(45.4%,35.9%,45.8%respectively,P<0.01)compared to the control group.Clinical and imaging outcomes did not differ significantly between the IU-PAE group and the control group.In the 2 clinical failures of IU-PAE(both in subgroup A),the extent of prostatic infarction(demonstrated by iCEUS)was significantly smaller compared to the rest of the IU-PAE group.CONCLUSION In selected patients,IU-PAE is associated with comparable outcomes,but with lower radiation exposure and a shorter procedure compared to bilateral PAE.iCEUS could facilitate patient selection for IU-PAE.

CT colonography in the diagnosis and management of colorectal cancer:Emphasis on pre-and post-surgical evaluation

This article addresses the use of computed tomographic colonography (CTC) for the diagnosis and management of colorectal cancer, focusing on presurgical evaluation of the colon proximal to an occlusive cancer and surveillance after cancer resection surgery. The key evidences accumulated in the literature and future work needed are summarized. CTC is a technically robust and the most practical method to evaluate the colon proximal to an occlusive cancer, which prevents colonoscopic examination past the occlusion, either before or after metallic stent placement. The high sensitivity of CTC for detecting cancers and advanced adenomas in the proximal colon can help prevent additional surgical procedures in patients showing negative results. However, the accuracy of CTC for distinguishing intramural cancers from adenomas is low, and the technique is limited in guiding management when a medium-sized lesion that do not show invasive features such as pericolic extension or nodal metastasis is found in the proximal colon. A maximal diameter &#x02265; 15 mm has been proposed as a criterion for surgical removal of proximal lesions. However, this needs to be verified in a larger cohort. In addition, the influence of presurgical CTC results on the current post-cancer resection colonic surveillance timeline remains to be determined. CTC can be readily added to the routine abdominopelvic CT in the form of contrast-enhanced CTC, which can serve as an effective stand-alone tool for post-cancer resection surveillance of both the colorectum and extracolonic organs. Although the accuracy of CTC has been demonstrated, its role in the current colonoscopy-based postoperative colonic surveillance protocols remains to be determined. Readers of CTC also need to be knowledgeable on the colonic lesions that are unique to the postoperative colon.