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.

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）.

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.

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.

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.

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.

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.

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.

Computed tomography vs liver stiffness measurement and magnetic resonance imaging in evaluating esophageal varices in cirrhotic patients:A systematic review and meta-analysis

BACKGROUND Computed tomography(CT),liver stiffness measurement(LSM),and magnetic resonance imaging(MRI)are non-invasive diagnostic methods for esophageal varices(EV)and for the prediction of high-bleeding-risk EV(HREV)in cirrhotic patients.However,the clinical use of these methods is controversial.AIM To evaluate the accuracy of LSM,CT,and MRI in diagnosing EV and predicting HREV in cirrhotic patients.METHODS We performed literature searches in multiple databases,including Pub Med,Embase,Cochrane,CNKI,and Wanfang databases,for articles that evaluated the accuracy of LSM,CT,and MRI as candidates for the diagnosis of EV and prediction of HREV in cirrhotic patients.Summary sensitivity and specificity,positive likelihood ratio and negative likelihood ratio,diagnostic odds ratio,and the areas under the summary receiver operating characteristic curves were analyzed.The quality of the articles was assessed using the quality assessment of diagnostic accuracy studies-2 tool.Heterogeneity was examined by Q-statistic test and I2 index,and sources of heterogeneity were explored using metaregression and subgroup analysis.Publication bias was evaluated using Deek’s funnel plot.All statistical analyses were conducted using Stata12.0,Meta Disc1.4,and Rev Man5.3.RESULTS Overall,18,17,and 7 relevant articles on the accuracy of LSM,CT,and MRI in evaluating EV and HREV were retrieved.A significant heterogeneity was observed in all analyses(P<0.05).The areas under the summary receiver operating characteristic curves of LSM,CT,and MRI in diagnosing EV and predicting HREV were 0.86(95%confidence interval[CI]:0.83-0.89),0.91(95%CI:0.88-0.93),and 0.86(95%CI:0.83-0.89),and 0.85(95%CI:0.81-0.88),0.94(95%CI:0.91-0.96),and 0.83(95%CI:0.79-0.86),respectively,with sensitivities of 0.84(95%CI:0.78-0.89),0.91(95%CI:0.87-0.94),and 0.81(95%CI:0.76-0.86),and 0.81(95%CI:0.75-0.86),0.88(95%CI:0.82-0.92),and 0.80(95%CI:0.72-0.86),and specificities of 0.71(95%CI:0.60-0.80),0.75(95%CI:0.68-0.82),and 0.82(95%CI:0.70-0.89),and 0.73(95%CI:0.66-0.80),0.87(95%CI:0.81-0.92),and 0.72(95%CI:0.62-0.80),respectively.The corresponding positive likelihood ratios were 2.91,3.67,and 4.44,and 3.04,6.90,and2.83;the negative likelihood ratios were 0.22,0.12,and 0.23,and 0.26,0.14,and 0.28;the diagnostic odds ratios were 13.01,30.98,and 19.58,and 11.93,49.99,and 10.00.CT scanner is the source of heterogeneity.There was no significant difference in diagnostic threshold effects(P>0.05)or publication bias(P>0.05).CONCLUSION Based on the meta-analysis of observational studies,it is suggested that CT imaging,a non-invasive diagnostic method,is the best choice for the diagnosis of EV and prediction of HREV in cirrhotic patients compared with LSM and MRI.

Imaging features of malignant vs stone-induced biliary obstruction:Aspects to consider

Radiological studies play a crucial role in the evaluation of patients with biliary duct obstruction,allowing for the guidance of clinical diagnosis towards a malignant or stone-induced etiology through the recognition of relevant imaging features,which must be continuously revisited given their prognostic significance.This article aims to emphasize the importance of recognizing crucial imaging aspects of malignant and stone-induced biliary obstruction.

Value of three-dimensional reconstructions in pancreatic carcinoma using multidetector CT:Initial results

AIM:To evaluate the use of three-dimensional imaging of pancreatic carcinoma using multidetector computed tomography(CT)in a prospective study.METHODS:Ten patients with suspected pancreatic tumors were examined prospectively using multidetec-tor CT(Somatom Sensation 16,Siemens,Erlangen,Germany).The images were evaluated for the pres-ence of a pancreatic carcinoma and invasion of the peripancreatic vessels and surrounding organs.Using the isotropic CT data sets,a three-dimensional image was created with automatic vascular analysis and semi-automatic segmentation of the organs and pancreatic tumor by a radiologist.The CT examinations and the three-dimensional images were presented to the sur-geon directly before and during the patient's operation using the Medical Imaging Interaction Toolkit-based software "ReLiver".Immediately after surgery,the value of the two images was judged by the surgeon.The operation and the histological results served as the gold standard.RESULTS:Nine patients had a pancreatic carcinoma(all pT3),and one patient had a serous cystadenoma.One tumor inf iltrated the superior mesenteric vein.The inf iltration was correctly evaluated.All carcinomas were resectable.In comparison to the CT image with axial and coronal reconstructions,the three-dimensional image was judged by the surgeons as better for operation planning and consistently described as useful.CONCLUSION:A 3D-image of the pancreas repre-sents an invaluable aid to the surgeon.However,the 3D-software must be further developed in order to be integrated into daily clinical routine.

Unusual gastric tumors and tumor-like lesions: Radiological with pathological correlation and literature review

Although gastric tumors have overlapping radiologic appearances, some unusual tumors may present specific imaging features. Using multidetector computed tomography(MDCT), with water as a negative oral contrast agent and intravenous contrast medium, can provide critical information for the diagnosis of gastric diseases. In addition, MDCT can evaluate the involvement of the gastric wall and extragastric extent of the disease, as compared with gastroenteroscopy and double-contrast upper gastrointestinal study. Regarding lesion location and size, enhancing and growth patterns, presence of calcification or fat, and involvement of the gastric wall and adjacent structures, CT may provide useful information. In this review article, we review the relevant literature and discuss the CT features and the histopathologic findings of different types of gastric lesions. The lesions are divided into benign(glomus tumors, schwannomas, leiomyomas, and lipomas), malignant(gastrointestinal stromal tumors, mucinous carcinomas, lymphomas, and carcinoid tumors), and tumor-like lesions(ectopic pancreas and bezoar). Familiarity with imaging appearances and pathologic findings can help physicians make an accurate diagnosis.

Multimodality imaging in apical hypertrophic cardiomyopathy

Apical hypertrophic cardiomyopathy(AHCM) is a relatively rare morphologic variant of HCM in which the hypertrophy of myocardium is localized to the left ventricular apex. Symptoms of AHCM might vary from none to others mimic coronary artery disease including acute coronary syndrome, thus resulting in inappropriate hospitalization. Transthoracic echocardiography is the firstline imaging technique for the diagnosis of hypertrophic cardiomyopathies. However, when the hypertrophy of the myocardium is localized in the ventricular apex might results in missed diagnosis. Aim of this paper is to review the different imaging techniques used for the diagnosis of AHCM and their role in the detection and comprehension of this uncommon disease.

MRI versus 64-row MDCT for diagnosis of hepatocellular carcinoma

AIM： To compare the diagnostic capability of multidetector computed tomography （MDCT） and magnetic resonance imaging （MRI） for the detection of hepatocellular carcinoma （HCC） tumour nodules and their effect on patient management. METHODS： A total of 28 patients （25 male, 3 female, mean age 67 ± 10.8 years） with biopsy-proven HCC were investigated with 64-row MDCT （slice 3 mm native, arterial and portal-venous phase, 120 mL Iomeprol, 4 mL/s, delay by bolus trigger） and MRI （Tlfs fl2d TE/ TR 2.72/129 ms, T2tse TE/TR 102/4000 ms, 5-phase dynamic contrast-enhanced Tlfs fl3d TE/TR 1.56/4.6, Gadolinium-DTPA, slice 4 mm）. Consensus reading of both modalities was used as reference. Tumour nodules were analyzed with respect to number, size, and location. RESULTS： In total, 162 tumour nodules were detected by consensus reading. MRI detected significantly more tumour nodules （159 vs 123, P 〈 0.001） compared to MDCT, with the best sensitivity for early arterial phase MRI. False-negative CT findings included nodules ≤ 5 mm （n = 5）, ≤ 10 mm （n = 17）, ≤ 15 mm （n= 12）,≤20mm（n=4）,andlnodule〉20mm.MRI missed 2 nodules ≤ 10 mm and 1 nodule ≤ 15 mm. On MRI, nodule diameters were greater than on CT （29.2 ≤25.1 mm, range 5-140 mm vs 24.1 ± 22.7 mm, range 4-129 mm, P 〈 0.005）. In 2 patients, MDCT showed only unilobar tumour spread, whereas MRI revealed additional nodules in the contralateral lobe. Detection of these nodules could have changed the therapeutic strategy. CONCLUSION： Contrast-enhanced MRI is superior to 64-row MDCT for the detection of HCC nodules. Patients should be allocated to interventional or operative treatment according to a dedicated MRI-protocol.

Multifocal autoimmune pancreatitis:A retrospective study in a single tertiary center of 26 patients with a 20-year literature review

BACKGROUND Multifocal-type autoimmune pancreatitis(AIP),sometimes forming multiple pancreatic masses,is frequently misdiagnosed as pancreatic malignancy in routine clinical practice.It is critical to know the imaging features of multifocaltype AIP to prevent misdiagnosis and unnecessary surgery.To the best of our knowledge,there have been no studies evaluating the value of diffusionweighted imaging(DWI),axial fat-suppressed T1 weighted image(T1WI),and dynamic contrast enhanced-computed tomography(DCE-CT)in detecting the lesions of multifocal-type AIP.AIM To clarify the exact prevalence and radiological findings of multifocal AIP in our cohorts and compare the sensitivity of DWI,axial fat-suppressed T1WI,and DCECT for detecting AIP lesions.We also compared radiological features between multifocal AIP and pancreatic ductal adenocarcinoma with several key imaging landmarks.METHODS Twenty-six patients with proven multifocal AIP were retrospectively included.Two blinded independent radiologists rated their confidence level in detecting the lesions on a 5-point scale and assessed the diagnostic performance of DWI,axial fat-suppressed T1WI,and DCE-CT.CT and magnetic resonance imaging of multifocal AIP were systematically reviewed for typical imaging findings and compared with the key imaging features of pancreatic ductal adenocarcinoma.RESULTS Among 118 patients with AIP,26(22.0%)had multiple lesions(56 lesions).Ulcerative colitis was associated with multifocal AIP in 7.7%(2/26)of patients,and Crohn’s disease was present in 15.3%(4/26)of patients.In multifocal AIP,multiple lesions,delayed homogeneous enhancement,multifocal strictures of the main pancreatic duct,capsule-like rim,lower apparent diffusion coefficient values,and elevated serum Ig4 level were observed significantly more frequently than pancreatic ductal adenocarcinoma,whereas the presence of capsule-like rim in multifocal-type AIP was lower in frequency than total AIP.Of these lesions of multifocal AIP,DWI detected 89.3%(50/56)and 82.1%(46/56)by the senior and junior radiologist,respectively.CONCLUSION Multifocal AIP is not as rare as previously thought and was seen in 22.0%of our patients.The diagnostic performance of DWI for detecting multifocal AIP was best followed by axial fat-suppressed T1WI and DCE-CT.

Multi-slice computed tomography for diagnosis of combined thoracoabdominal injury

Purpose： To investigate the diagnostic value of multi-slice computed tomography （MSCT） for combined thoracoabdominal injury. Methods： A retrospective study was conducted to analyze the clinical data and MSCT images of 68 patients who sustained a combined thoracoabdominal injury associated with diaphragm rupture, and 18 patients without diaphragm rupture. All the patients were admitted and treated in the Chongqing Emergency Medical Center （a level I trauma center） between July 2005 and February 2014. There were 71 males and 15 females with a mean age of 39.1 years （range 13-88 years）. Among the 86 patients, 40 patients suffered a penetrating injury, 46 suffered a blunt injury as a result of road traffic accident in 21 cases, fall from a height in 16, and crushing injury in 9. The MSCT images were retrospectively reviewed by two radiologists. The results of CT diagnosis were compared with surgical findings and/or follow-up results. Results： Among the 86 cases, diaphragm discontinuity was found in 29 cases, segmental nonrecognition of the diaphragm in 14, diaphragmatic hernia in 21, collar sign in 14, dependent viscera sign in 18, elevated abdominal organs in 21, bowel wall thickening and/or hematoma in 6, and pneumoperitoneum in 8. CT diagnostic accuracy for diaphragm rupture was 88.4% in the right side and 90.7% in the left side. CT diagnostic accuracy for hemopneumothorax, pulmonary contusion, mediastinal hemorrhage, kidney and adrenal gland injuries was 100%, while for liver, spleen and pancreas injuries was 96.5%, 96.5g, 94.2% respectively. Conclusion： To reach an early diagnosis of combined thoracoabdominal injury, surgeons and radiologists should be familiar with all kinds of images which might show signs of diaphragm rupture, such as diaphragm discontinuity, segmental nonrecognition of the diaphragm, dangling diaphragm sign, diaphragm herniation, collar sign, dependent viscera sign, and elevated abdominal organs.

Risk factors of lymphatic metastasis complement poor radiological detection in gallbladder cancer

AIM: To explore risk factors of lymphatic metastasis (LM) in gallbladder cancer, and their potential to complement unsatisfactory radiological detection.

Ascaris-mimicking common bile duct stone: A case report

BACKGROUND In most cases,it is not difficult to differentiate common bile duct(CBD)stone from Ascaris infection because they are different disease entities and have different imaging findings.The two diseases usually demonstrate unique characteristic findings on computed tomography or magnetic resonance cholangiopancreatography.However,we report a rare case from our experience in which a CBD stone mimicked and was misdiagnosed as Ascaris.CASE SUMMARY A 72-year-old male presented with elevated serum liver enzymes.Computed tomography showed a hyper-attenuated,elongated lesion in the CBD lumen and associated biliary inflammation.Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography revealed a linear filling defect in the bile duct.Moreover,elongated echogenic material with a central hypoechogenic area was seen on endoscopic ultrasound.Although the imaging findings caused us to suspect infection with the nematode Ascaris,the lesion was revealed to be a dark-brown-colored CBD stone through endoscopic extraction.CONCLUSION We report a rare case of a CBD stone that mimicked Ascaris.We also review the literature for side-by-side comparisons of the imaging features of CBD stones and ascariasis.

Imaging of pannus formation in patients with mechanical heart valves

Patient-prosthesis mismatch(PPM) should be recognized in patients with elevated transprosthetic gradients but without leaflet immobility, since the treatment strategy may differ in either etiology. However, thrombus and/or pannus formation should be excluded before a diagnosis of PPM is made. Particularly, pannus formation may not be diagnosed with 2-dimensional transesophageal echocardiography. Electrocardiographically gated 64-section multidetector computed tomography(MDCT) may be a promising tool in diagnosing or excluding pannus formation. Our report underlines the utility of MDCT in this regard and also emphasizes the importance of recognition of PPM as a differential diagnosis in such patients.