Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients

BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and third for mortality.Knowledge of the invasive depth of the tumor is vital to treatment decisions.AIM To evaluate the diagnostic performance of double contrast-enhanced ultrasonography(DCEUS)for preoperative T staging in patients with GC by comparing with multi-detector computed tomography(MDCT).METHODS This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023.Patients underwent DCEUS,including ultrasonography(US)and intravenous contrast-enhanced ultrasonography(CEUS),and MDCT examinations for the assessment of preoperative T staging.Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual.The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard.RESULTS A total of 229 patients with GC(80 T1,33 T2,59 T3 and 57 T4)were included.Overall accuracies were 86.9%for DCEUS and 61.1%for MDCT(P<0.001).DCEUS was superior to MDCT for T1(92.5%vs 70.0%,P<0.001),T2(72.7%vs 51.5%,P=0.041),T3(86.4%vs 45.8%,P<0.001)and T4(87.7%vs 70.2%,P=0.022)staging of GC.CONCLUSION DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT,and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making.

Role of multidetector computed tomography angiography in nonvariceal upper gastrointestinal bleeding:A comprehensive review

Non-variceal upper gastrointestinal bleeding(NVUGIB)is a common gastroenterological emergency associated with significant morbidity and mortality.Upper gastrointestinal endoscopy is currently recommended as the gold standard modality for both diagnosis and treatment,with computed tomography traditionally playing a limited role in the diagnosis of acute NVUGIB.Following the introduction of multidetector computed tomography(MDCT),this modality is emerging as a promising tool in the diagnosis of NVUGIB.However,to date,evidence concerning the role of MDCT in the NVUGIB diagnosis is still lacking.The aim of our study was to review the current evidence concerning the role of MDCT in the diagnosis of acute NVUGIB.

Rectal cancer staging: Multidetector-row computed tomography diagnostic accuracy in assessment of mesorectal fascia invasion

AIM: To assess the diagnostic accuracy of multidetectorrow computed tomography(MDCT) as compared with conventional magnetic resonance imaging(MRI), in identifying mesorectal fascia(MRF) invasion in rectal cancer patients.METHODS: Ninety-one patients with biopsy proven rectal adenocarcinoma referred for thoracic and abdominal CT staging were enrolled in this study. The contrast-enhanced MDCT scans were performed on a 256 row scanner(ICT, Philips) with the following acquisition parameters: tube voltage 120 KV, tube current 150-300 m As. Imaging data were reviewed as axial and as multiplanar reconstructions(MPRs) images along the rectal tumor axis. MRI study, performed on 1.5 T with dedicated phased array multicoil, included multiplanar T2 and axial T1 sequences and diffusion weighted images(DWI). Axial and MPR CT images independently were compared to MRI and MRF involvement was determined. Diagnostic accuracy of both modalities was compared and statistically analyzed.RESULTS: According to MRI, the MRF was involved in 51 patients and not involved in 40 patients. DWI allowed to recognize the tumor as a focal mass with high signal intensity on high b-value images, compared with the signal of the normal adjacent rectal wall or with the lower tissue signal intensity background. The number of patients correctly staged by the native axial CT images was 71 out of 91(41 with involved MRF; 30 with not involved MRF), while by using the MPR 80 patients were correctly staged(45 with involved MRF; 35 with not involved MRF). Local tumor staging suggested by MDCT agreed with those of MRI, obtaining for CT axial images sensitivity and specificity of 80.4% and 75%, positive predictive value(PPV) 80.4%, negative predictive value(NPV) 75% and accuracy 78%; while performing MPR the sensitivity and specificity increased to 88% and 87.5%, PPV was 90%, NPV 85.36% and accuracy 88%. MPR images showed higher diagnostic accuracy, in terms of MRF involvement, than native axial images, as compared to the reference magnetic resonance images. The difference in accuracy was statistically significant(P = 0.02). CONCLUSION: New generation CT scanner, using high resolution MPR images, represents a reliable diagnostic tool in assessment of loco-regional and whole body staging of advanced rectal cancer, especially in patients with MRI contraindications.

Imaging features of solid pseudopapillary tumor of the pancreas on multi-detector row computed tomography

AIM： To retrospectively analyze the imaging features of solid-pseudopapillary tumors （SPTs） of the pancreas on multi-detector row computed tomography （MDCT） and define the imaging findings suggestive of malignant potential. METHODS： A total of 24 consecutive cases with surgically and pathologically confirmed SPTs of the pancreas underwent preoperative abdominal MDCT studies in our hospital. All axial CT images, CT angiographic images, and coronally and sagittally reformed images were obtained. The images were retrospectively reviewed at interactive picture archiving and communication system workstations. RESULTS： Of the 24 cases of SPTs, 11 cases （45.8%） occurred in the pancreatic head and seven （29.1%） in the tail. Eighteen were pathologically diagnosed as benign and six as malignant. MDCT diagnosis of SPTs was well correlated with the surgical and pathological results （Kappa = 0.6, P 〈 0.05）. The size of SPTs ranged from 3 to 15 cm （mean, 5.8 cm）. When the size of the tumor was greater than 6 cm （including 6 cm）, the possibilities of vascular （8 vs 1） and capsular invasion （9 vs 0） increased significantly （P 〈 0.05）.Two pathologically benign cases with vascular invasion and disrupted capsule on MDCT presented with local recurrence and hepatic metastases during follow-up about 1 year after the resection of the primary tumors. CONCLUSION： Vascular and capsular invasion with superimposed spread into the adjacent pancreatic parenchyrna and nearby structures in SPTs of the pancreas can be accurately revealed by MDCT preoperatively. These imaging findings are predictive of the malignant potential associated with the aggressive behavior of the tumor, even in the pathologically benign cases.

Predictive value of multi-detector computed tomography for accurate diagnosis of serous cystadenoma:Radiologic-pathologic correlation

AIM： To identify multi-detector computed tomography （MDCT） features most predictive of serous cystadenomas （SCAs）, correlating with histopathology, and to study the impact of cyst size and MDCT technique on reader performance. METHODS： The MDCT scans of 164 patients with surgically verified pancreatic cystic lesions were reviewed by two readers to study the predictive value of various morphological features for establishing a diagnosis of SCAs. Accuracy in lesion characterization and reader confidence were correlated with lesion size （≤3 cm or 〉≥3 cm） and scanning protocols （dedicated vs routine）. RESULTS： 28/164 cysts （mean size, 39 mm; range, 8-92 mm） were diagnosed as SCA on pathology. The MDCT features predictive of diagnosis of SCA were microcystic appearance （22/28, 78.6%）, surface Iobulations （25/28, 89.3%） and central scar （9/28, 32.4%）. Stepwise logistic regression analysis showed that only microcystic appearance was significant for CT diagnosis of SCA （P = 0.0001）. The sensitivity, specificity and PPV of central scar and of combined microcystic appearance and Iobulations were 32.4%/100%/100% and 68%/100%/100%, respectively. The reader confidence was higher for lesions 〉 3 cm （P = 0.02） and for MDCT scans performed using thin collimation （1.25-2.5 mm） compared to routine 5 mm collimation exams （P 〉 0.05）. CONCLUSION： Central scar on MDCT is diagnostic of SCA but is seen in only one third of SCAs. Microcystic morphology is the most significant CT feature in diagnosis of SCA. A combination of microcystic appearance and surface Iobulations offers accuracy comparable to central scar with higher sensitivity.

Clinical impact of multidetector computed tomography before double-balloon enteroscopy for obscure gastrointestinal bleeding

AIM： To evaluate the clinical impact of multidetector computed tomography （MDCT） before double-balloon endoscopy （DBE） for patients with obscure gastrointestinal bleeding （OGIB）.

Diagnosis of Congenital Aortic Arch Anomalies in Chinese Children by Multi-Detector Computed Tomography Angiography

Summary： The purpose of this study was to evaluate the value of multi-detector computed tomography （MDCT） angiography for the diagnosis of congenital aortic arch anomalies and present the radiological images of congenital aortic arch anomalies in Chinese children. MDCT angiography and transthoracic echocardiography （TTE） were applied for the diagnosis of congenital aortic arch anomalies in 362 Chi- nese children between May 2006 and December 2011 （age ranges from 5 days to 12 years; mean age, 3.3 years）. Surgery and/or catheter angiography （CA） were conducted in all patients to confirm the final diagnosis. In the 362 Chinese children with congenital heart anomalies, congenital aortic arch anomalies were definitely diagnosed in 198 children and 164 children ruled out by operation and/or （CA）. Among the 198 children with anomalies, coarctation of aorta （CoA）, interruption of aortic arch （IAA）, fight aor- tic arch, aberrant right subclavian artery and double aortic arch were diagnosed in 134, 32, 20, 10 and 2 children respectively, and there were 6 cases with uncommon congenital aortic arch anomalies： 2 had double aortic arch including 1 with five branches of the aortic arch, 2 had isolation of the right sub- clavian artery with two patent ductus arteriosus （PDA）, 1 had an isolation of the common carotid artery with a PDA, and 1 had double PDA with a single ventricle and pulmonary artery atresia. Among the 32 children with IAA, 28 were of type A, and 4 were of type B. The diagnostic sensitivity, specificity and accuracy of MDCT angiography for congenital aortic arch anomaiies were 100% （198/198）, 98% （161/164） and 99% （359/362）, respectively. The diagnostic sensitivity, specificity and accuracy of TTE were 92% （182/198）, 81% （133/164） and 87% （315/362）, respectively. In conclusion, MDCT angiogra- phy is a reliable, noninvasive imaging technique for the diagnosis of congenital aortic arch anomalies in children. Sometimes, even more information can be obtained from this technique than from conven- tional angiography.

Evaluation of human epidermal growth factor receptor 2 status of breast cancer using preoperative multidetector computed tomography with deep learning and handcrafted radiomics features

Objective:To evaluate the human epidermal growth factor receptor 2(HER2)status in patients with breast cancer using multidetector computed tomography(MDCT)-based handcrafted and deep radiomics features.Methods:This retrospective study enrolled 339 female patients(primary cohort,n=177;validation cohort,n=162)with pathologically confirmed invasive breast cancer.Handcrafted and deep radiomics features were extracted from the MDCT images during the arterial phase.After the feature selection procedures,handcrafted and deep radiomics signatures and the combined model were built using multivariate logistic regression analysis.Performance was assessed by measures of discrimination,calibration,and clinical usefulness in the primary cohort and validated in the validation cohort.Results:The handcrafted radiomics signature had a discriminative ability with a C-index of 0.739[95%confidence interval(95%CI):0.661-0.818]in the primary cohort and 0.695(95%CI:0.609-0.781)in the validation cohort.The deep radiomics signature also had a discriminative ability with a C-index of 0.760(95%CI:0.690-0.831)in the primary cohort and 0.777(95%CI:0.696-0.857)in the validation cohort.The combined model,which incorporated both the handcrafted and deep radiomics signatures,showed good discriminative ability with a C-index of 0.829(95%CI:0.767-0.890)in the primary cohort and 0.809(95%CI:0.740-0.879)in the validation cohort.Conclusions:Handcrafted and deep radiomics features from MDCT images were associated with HER2 status in patients with breast cancer.Thus,these features could provide complementary aid for the radiological evaluation of HER2 status in breast cancer.

Magnetic resonance imaging and multi-detector computed tomography assessment of extracellular compartment in ischemic and non-ischemic myocardial pathologies

Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume(ECV) in myocardium is critical to initiate effective treatment. The three compartments in healthy myocardium are: intravascular(approximately 10% of tissue volume), interstitium(approximately 15%) and intracellular(approximately 75%). Myocardial cells, fibroblasts and vascular endothelial/smooth muscle cells represent intracellular compartment and the main proteins in the interstitium are types Ⅰ/Ⅲ collagens. Microscopic studies have shown that expansion of ECV is an important feature of diffuse physiologic fibrosis(e.g., aging and obesity) and pathologic fibrosis [heart failure, aortic valve disease, hypertrophic cardiomyopathy, myocarditis, dilated cardiomyopathy, amyloidosis, congenital heart disease, aortic stenosis, restrictive cardiomyopathy(hypereosinophilic and idiopathic types), arrythmogenic right ventricular dysplasia and hypertension]. This review addresses recent advances in measuring of ECV in ischemic and non-ischemic myocardial pathologies. Magnetic resonance imaging(MRI) has the ability to characterize tissue proton relaxation times(T1, T2, and T2*). Proton relaxation times reflect the physical and chemical environments of water protons in myocardium. Delayed contrast enhanced-MRI(DE-MRI) and multi-detector computed tomography(DE-MDCT) demonstrated hyper-enhanced infarct, hypo-enhanced microvascular obstruction zone and moderately enhanced peri-infarct zone, but are limited for visualizing diffuse fibrosis and patchy microinfarct despite the increase in ECV. ECV can be measured on equilibrium contrast enhanced MRI/MDCT and MRI longitudinal relaxation time mapping. Equilibrium contrast enhanced MRI/MDCT and MRI T1 mapping is currently used, but at a lower scale, as an alternative to invasive sub-endomyocardial biopsies to eliminate the need for anesthesia, coronary catheterization and possibility of tissue sampling error. Similar to delayed contrast enhancement, equilibrium contrast enhanced MRI/MDCT and T1 mapping is completely noninvasive and may play a specialized role in diagnosis of subclinical and other myocardial pathologies. DE-MRI and when T1-mapping demonstrated sub-epicardium, sub-endocardial and patchy mid-myocardial enhancement in myocarditis, Behcet's disease and sarcoidosis, respectively. Furthermore, recent studies showed that the combined technique of cine, T2-weighted and DE-MRI technique has high diagnostic accuracy for detecting myocarditis. When the tomographic techniques are coupled with myocardial perfusion and left ventricular function they can provide valuable information on the progression of myocardial pathologies and effectiveness of new therapies.

Role of multidetector computed tomography in patients with acute infectious colitis

BACKGROUND The role of multidetector computed tomography(MDCT)in patients with acute infectious colitis is still unclear.AIM To examine the usefulness of MDCT in distinguishing the etiology of acute infectious colitis.METHODS Overall,244 patients who met the criteria for acute infectious colitis and visited the Hospital from February 2015 to 2018 were retrospectively enrolled and divided into two groups(bacterial:204,viral:40)according to causes of acute colitis,based on stool PCR.Eleven MDCT parameters,including wall thickening,submucosal edema,mucosal enhancement,serosa involvement,empty colon sign,small bowel involvement,comb sign,continuous distribution,accordion sign,mucosal thickening,and lymph node enlargement,were constructed in a blinded fashion.RESULTS MDCT parameters of wall thickening(OR:13.60;95%CI:5.80–31.88;P<0.001),submucosal edema(OR:36.08;95%CI:13.54–96.13;P<0.001),mucosal enhancement(OR:22.55;95%CI:9.28–54.81;P<0.001),serosal involvement(OR:14.50;95%CI:3.33–63.23;P<0.001),empty colon sign(OR:6.68;95%CI: 2.44–18.32;P < 0.001), continuous distribution (OR: 24.09;95%CI: 9.38–61.90;P < 0.001), accordionsign (OR: 9.02;95%CI: 1.12–72.35;P = 0.038), mucosal thickening (OR: 46.41;95%CI: 10.38–207.51;P< 0.001), and lymph node enlargement (OR: 4.39;95%CI: 1.22–15.72;P = 0.023) were significantlyassociated with bacterial colitis. At least one positive finding in four CT outcomes (submucosaledema, mucosal enhancement, continuous distribution, mucosal thickening) in summer showed ahigh probability of bacterial colitis (sensitivity, 41.67;specificity, 92.50;OR: 24.95).CONCLUSIONMDCT provides many clues that can be useful in suggesting a specific etiology of acute infectiouscolitis.

Scattering correction method for panel detector based cone beam computed tomography system

A scattering correction method for a panel detector based cone beam computed tomography system is presented. First, the x-ray spectrum of the system is acquired by using the Monte Carlo simulation method. Secondly, scattered photon distribution is calculated and stored as correction matrixes by using the Monte Carlo simulation method according to scanned objects and computed tomography system specialties. Thirdly, scattered photons are removed from projection data by correction matrixes. A comparison of reconstruction image between before and after scattering correction demonstrates that the scattering correction method is effective for the panel detector based cone beam computed tomography system.

Colonic perforation by a transmural and transvalvular migrated retained sponge:Multi-detector computed tomography findings

Transmural migrated retained sponges usually impact at the level of the ileo-cecal valve leading to a small bowel obstruction.Once passed through the ileo-cecal valve,a retained sponge can be propelled forward by peristaltic activity and eliminated with feces.We report the case of a 52-year-old female with a past surgical history and recurrent episodes of abdominal pain and constipation.On physical examination,a generalized resistance was observed with tenderness in the right flank.Contrast-enhanced multi-detector computed tomography findings were consistent with a perforated right colonic diverticulitis with several out-pouchings at the level of the ascending colon and evidence of free air in the right parieto-colic gutter along with an air-fluid collection within the mesentery.In addition,a ring-shaped hyperdense intraluminal material was also noted.At surgery,the ascending colon appeared irregularly thickened and folded with a focal wall interruption and a peri-visceral abscess at the level of the hepatic flexure,but no diverticula were found.A right hemi-colectomy was performed and on dissection of the surgical specimen a retained laparotomy sponge was found in the bowel lumen.

Abdominal crush injury in the Sichuan earthquake evaluated by multidetector computed tomography

AIM: To investigate the features of abdominal crush injuries resulting from an earthquake using multidetector computed tomography (MDCT). METHODS: Fifty-one survivors with abdominal crush injuries due to the 2008 Sichuan earthquake underwent emergency non-enhanced scans with 16-row MDCT. Data were reviewed focusing on anatomic regions including lumbar vertebrae, abdominal wall soft tissue, retroperitoneum and intraperitoneal space; and types of traumatic lesions. RESULTS: Fractures of lumbar vertebrae and abdominal wall soft tissue injuries were more common than retro- and intraperitoneal injuries (P < 0.05). With regard to the 49 lumbar vertebral fractures in 24 patients, these occurred predominantly in the transverse process (P < 0.05), and 66.67% of patients (16/24) had fractures of multiple vertebrae, predominantly two vertebrae in 62.5% of patients (10/16), mainly in L1-3 vertebrae in 81.63% of the vertebrae (40/49). Retroperitoneal injuries occurred more frequently than intraperitoneal injuries (P < 0.05), and renal and liver injuries were most often seen in the retroperitoneum and in the intraperitoneal space, respectively (all P < 0.05). CONCLUSION: Transverse process fractures in two vertebrae among L1-3 vertebrae, injury of abdominal wall soft tissue, and renal injury might be features of earthquake-related crush abdominal injury.

Role of clinical data and multidetector computed tomography findings in acute superior mesenteric artery embolism

BACKGROUND Superior mesenteric artery embolism(SMAE)has acute onset and fast progression,which seriously threatens the life of patients.Multidetector computed tomography(MDCT)is one of the most important diagnostic methods for SMAE,which plays an important role in the diagnosis and prognosis of SMAE.AIM To evaluate the value of combined clinical data and MDCT findings in the diagnosis of acute SMAE and predict the risk factors for SMAE-related death.METHODS Data from 53 SMAE patients who received abdominal MDCT multi-phase enhancement and superior mesenteric artery digital subtraction angiography examinations were collected.Univariate cox regression and multivariate cox model were used to analyze the correlation between death risk and clinical and computed tomography features in SMAE patients.RESULTS Univariate Cox regression model showed that intestinal wall thinning,intestinal wall pneumatosis,blood lactate>2.1 mmol/L and blood pH<7.35 increased the risk of death in patients with SMAE.After adjusting for age,sex,embolic involvement length and embolic distribution region,multivariate Cox regression model I showed that blood lactate>2.1 mmol/L(HR=5.26,95%CI:1.04-26.69,P=0.045)and intestinal wall thinning(HR=9.40,95%CI:1.05-83.46,P=0.044)were significantly increases the risk of death in patients with SMAE.CONCLUSION For patients with SAME,increased blood lactate and intestinal wall thinning are the risk factors for death;hence,close monitoring may reduce the mortality rate.Clinical observation combined with MDCT signs can significantly improve SMAE diagnosis.

Acquired renal arteriovenous malformation:the diagnostic value of three-dimensional multidetector-row computed tomography

Objective To evaluate the diagnostic value of three-dimensional multidetector-row computed tomogra- phy （MDCT） in detecting acquired renal arteriovenous malformation （RAVM） and to compare its perfor- mance with that of ultrasonography and digital subtraction angiography （DSA）. Methods The institutional review board approved this retrospective study and written informed consent was obtained from all patients before examination. All 14 patients with acquired RAVM underwent MDCT, including cortical and medullary phase enhancement angiography and three-dimensional （3D） reconstruc- tion. Five and nine patients were further examined and their diagnoses confirmed by DSA and surgery, respectively. The MDCT images, including 3D reconstructions, were analyzed for RAVM independently and in consensus by two observers using a workstation. Results Among the 14 patients with acquired RAVM, 12 with maximum lesion diameter 〉 10 mm, and one with a maximum lesion diameter between 5 and 10 ram, were correctly diagnosed with MDCT angiog- raphy. Among these patients, four diagnoses were confirmed by DSA. One patient with a lesion 5-10 mm in diameter was misdiagnosed with a renal aneurysm by MDCT angiography. The other one with the maxi- mum diameter of the lesion between 5 mm and 10 mm was misdiagnosed as renal aneurysm with MDCT angiography, which was diagnosed as renal arteriovenous malformation with DSA. Among 14 lesions in 14 patients, eight and six originated in the left and right kidney, respectively. Conclusion MDCT angiography can accurately diagnose RAVM and improve our understanding of the disease, which will allow clinicians to provide better care.

Coronary Artery Anomalies Detected by Multi-Detector Computed Tomography: A Single Centre Experience

Background: Coronary artery anomalies (CAA) prevalence represents less than 1% of congenital heart diseases. It includes anomalies in origin, course, and termination. Its detection has been easier with advances in imaging techniques using multi-detector computed tomography (MDCT). MDCT helps not only detection of the anomalous origin, but it allows delineation of the course and termination of the arteries, differentiation between benign and malignant courses, and guiding therapeutic interventions. Results: There were consecutive patients with a low-to-intermediate probability of coronary artery disease scanned with 128 MDCT. Each patient underwent a non-contrast prospective gating acquisition for coronary calcium scoring followed by contrast-enhanced helical retrospective gated scans for the detection of coronary artery origin, course, termination, and detection of concomitant atherosclerosis. We scanned 1000 patients with a mean age of 57.5 ± 8.3, and 68% were males. Thirty-two anomalies were noted (3.2%) including;nineteen (1.9%) anomalous origin from the opposite sinus, three (0.3%) anomalous left coronary arteries from the pulmonary artery (ALCAPA), one (0.1%) super dominant left anterior descending artery (LAD) giving origin to the posterior descending artery (PDA), three single coronary arteries (0.3%)in which the left main (LM) and right coronary arteries were originating with a common stem from the right coronary sinus (RCS)and the LM took a pre-pulmonic course. Along with six (0.6%) dual LAD including five (0.5%) patients with type I (short LAD and long diagonal), there was one (0.1%) type 4 with an extra LAD originating from the RCS with a pre-pulmonic course. Conclusions: MDCT allows easy detection of coronary anomalies with high spatial resolution and overcomes limitations in conventional invasive coronary angiography. Based on our study we recommend the use of MDCT as an efficient and feasible modality for the diagnosis of coronary anomalies once this pathology is clinically suspected.

Effectiveness of Multidetector Computed Tomography in Prosthetic Valve Endocarditis

Background: Redo aortic valve replacement for prosthetic valve endocarditis is a challenge for surgeons. Echocardiography is occasionally not an effective modality for the detection of infectious signs in prosthetic valve endocarditis. Case presentation: Herein, we report the case of a patient whose prosthetic valve endocarditis was detected by multidetector computed tomography and who successfully underwent redo aortic valve replacement. Preoperative echocardiography revealed no remarkable findings related to endocarditis such as perivalvular leakage or vegetation;however, multidetector computed tomography revealed a thickened right coronary cusp. Intraoperatively, the right coronary cusp was confirmed to be covered with thick infected tissue. The pathological findings revealed broad destruction due to infection of the right coronary cusp. Conclusion: Multidetector computed tomography was useful in detecting infectious signs in prosthetic valves.

Coronary arterial bypass graft patency evaluated by multi-detector computed tomography and magnetic resonance imaging

The progression of atherosclerosis of the coronary artery does not stop after coronary arterial bypass grafting (CABG) surgery.……

Common bile duct stones on multidetector computed tomography:Attenuation patterns and detectability

AIM:To investigate the attenuation patterns and detectability of common bile duct(CBD) stones by multidetector computed tomography(MDCT).METHODS:Between March 2010 and February 2012,191 patients with suspicion of CBD stones undergoing both MDCT and endoscopic retrograde cholangiopancreatography(ERCP) were enrolled and reviewed retrospectively.The attenuation patterns of CBD stones on MDCT were classified as heavily calcified,radiopaque,less radiopaque,or undetectable.The association between the attenuation patterns of CBD stones on MDCT and stone type consisting of pure cholesterol,mixed cholesterol,brown pigment,and black pigment and the factors related to the detectability of CBD stones by MDCT were evaluated.RESULTS:MDCT showed CBD stones in 111 of 130 patients in whom the CBD stones were demonstrated by ERCP with 85.4% sensitivity.The attenuation patterns of CBD stones on MDCT were heavily calcified 34(26%),radiopaque 31(24%),less radiopaque 46(35%),and undetectable 19(15%).The radiopacity of CBD stones differed significantly according to stone type(P < 0.001).From the receiver operating characteristic curve,stone size was useful for the determination of CBD stone by MDCT(area under curve 0.779,P < 0.001) and appropriate cut-off stone size on MDCT was 5 mm.The factors related to detectability of CBD stones on MDCT were age,stone type,and stone size on multivariate analysis(P < 0.05).CONCLUSION:The radiopacity of CBD stones on MDCT differed according to stone type.Stone type and stone size were related to the detectability by MDCT,and appropriate cut-off stone size was 5 mm.

Advances of multidetector computed tomography in the characterization and staging of renal cell carcinoma

Renal cell carcinoma(RCC) accounts for approximately 90%-95% of kidney tumors. With the widespread use of cross-sectional imaging modalities, more than half of RCCs are detected incidentally, often diagnosed at an early stage. This may allow the planning of more conservative treatment strategies. Computed tomography(CT) is considered the examination of choice for thedetection and staging of RCC. Multidetector CT(MDCT) with the improvement of spatial resolution and the ability to obtain multiphase imaging, multiplanar and threedimensional reconstructions in any desired plane brought about further improvement in the evaluation of RCC. Differentiation of RCC from benign renal tumors based on MDCT features is improved. Tumor enhancement characteristics on MDCT have been found closely to correlate with the histologic subtype of RCC, the nuclear grade and the cytogenetic characteristics of clear cell RCC. Important information, including tumor size, localization, and organ involvement, presence and extent of venous thrombus, possible invasion of adjacent organs or lymph nodes, and presence of distant metastases are provided by MDCT examination. The preoperative evaluation of patients with RCC was improved by depicting the presence or absence of renal pseudocapsule and by assessing the possible neoplastic infiltration of the perirenal fat tissue and/or renal sinus fat compartment.