Contrast-enhanced Abdominal Computed Tomography Scan Research Articles

Transarterial embolization in Wunderlich syndrome due to recanalization of giant renal angiomyolipoma pseudoaneurysm: a case report and literature review

BackgroundAcute spontaneous bleeding from renal angiomyolipoma (AML) is one of the causes of Wunderlich syndrome, a rare and potentially fatal clinical condition. Clinical deterioration will occur if there is a delay in urgent management. There are several management options for renal angiomyolipoma rupture. However, until now little is known about the case of recanalization from post-coil embolization of renal angiomyolipoma. There is no guideline about embolization technique for the management of recurrent bleeding after embolization or coil recanalization of renal angiomyolipoma.Case presentationA 55-year-old male has Wunderlich syndrome caused by recurrent bleeding of giant AML of the left renal due to coil recanalization compounded by a pseudoaneurysm and other bleeding site in bilateral giant renal angiomyolipoma which is showed by contrast-enhanced abdominal computed tomography scan. The patient underwent urgent transarterial embolization and some blood transfusion. Clinical improvement occurred and the patient discharged several days later.ConclusionsEmbolization for spontaneous bleeding or rebleeding of renal pseudoaneurysms may become the first choice of treatment in bilateral multiple renal angiomyolipoma rather than other managements which are available to preserve renal function.

Evaluating aortomesenteric parameters in a tertiary center of Nepal for superior mesenteric artery syndrome diagnosis and risk factors: cross-sectional study.

This study examines aortomesenteric angle (AMA) and distance (AMD), which are critical in superior mesenteric artery (SMA) syndrome. Addressing the scarcity of SMA cases, the research explores potential links with lower BMI and aims to establish normative data for diagnostic and predictive purposes, using contrast-enhanced computed tomography (CT) scans across various BMI and sex categories. A retrospective quantitative cross-sectional study was conducted on 189 patients undergoing abdominal contrast-enhanced CT scans between December 2019 and December 2020. Ethical clearance was obtained, and participants provided informed consent. Exclusion criteria targeted specific medical histories. Patient demographics, BMI categories, and imaging data were recorded. Helical 128-slice CT scans were employed, with sagittal-oblique multiplanar reconstructions for parameter assessments. Statistical analysis utilized SPSS 26.0, including Pearson correlation coefficients and mean calculations. The study reveals a mean AMA of 54.07°±8.53° and a mean distance of 16.25±3.44 mm. Elevated BMI is found to positively correlate with AMA and distance, indicating that higher BMI values may augment these parameters, with an additional positive correlation observed between AMA and distance. No significant correlations are found with patient age or sex. The study concludes that decreased BMI may pose a potential risk for SMA syndrome, as evidenced by the observed correlations with aortomesenteric parameters. Understanding these normal values in the Nepalese population is critical for accurate diagnoses and predictions using CT scans. The research highlights the impact of demographic factors on these parameters and emphasizes their significance in clinical assessments related to SMA syndrome.

Amoebic liver abscess in an adult Nigerian: A case report

Background: Amoebic liver abscess (ALA) is a parasitic infection caused by Entamoeba histolytica. ALA is a significant health concern, particularly in regions with poor sanitation and hygiene practices. Radiological imaging plays a crucial role in the diagnosis and management of ALA. Methods: We present a case report of a 40-year-old male patient with ALA. The patient presented to a radio diagnostic centre in Umuahia with right upper quadrant abdominal pain, fever,diarrhea and weight loss. Radiological evaluation was performed using abdominal ultrasound and contrast-enhanced CT scan. The imaging findings were correlated with clinical presentation and laboratory investigations. Results: The radiological findings revealed a focal hypoechoic lesion in the right hepatic lobe with ill-defined margins and internal echoes suggestive of liquefaction. The contrast-enhanced CT scan confirmed the presence of a well-defined, hypodense lesion with peripheral enhancement and central hypoattenuation. No evidence of biliary ductal dilatation or vascular invasion was observed. Based on the findings, a diagnosis of ALA was made, and the patient was initiated on intravenous metronidazole therapy. Follow-up imaging demonstrated a decrease in abscess size and resolution of internal echoes, indicating a positive response to treatment. Conclusion: Radiological imaging, including ultrasound and CT scan, plays a pivotal role in the diagnosis and management of ALA. The characteristic imaging findings, such as hypoechoic lesions with internal echoes and peripheral enhancement with central hypoattenuation, aid in differentiating ALA from other hepatic lesions. Early diagnosis and prompt initiation of appropriate therapy are crucial for favorable patient outcomes. Radiological follow-up allows monitoring of treatment response and guides further management decisions.

Intercostal hemangiomas coexisting with multiple hepatic hemangiomas: Clinical and imaging findings in a single case report with a review of the literature.

Intercostal hemangioma (IH) is an extremely rare disease, with only 18 cases reported in the past 30 years. Herein, we report the first case of IH coexisting with multiple hepatic hemangiomas, which recurred 32 months after surgery with rib erosion. IHs are invasive and difficult to distinguish from other intercostal tumors on imaging. To date, there have been no review articles on the imaging findings of IHs. We hope that this article will help clinicians improve their ability to diagnose and treat IH. A 58-year-old male came to our hospital with gastrointestinal disease. Chest tumors were accidentally discovered on routine chest computed tomography (CT). The patient had no chest symptoms. The patient also had multiple liver tumors that had been present for 2 years but with no remarkable changes. Plain chest CT revealed 2 adjacent masses protruding from the left chest wall into the thoracic cavity. Neurogenic tumors or hamartomas were suspected on enhanced CT scans. Abdominal contrast-enhanced computed tomography scan indicated multiple liver tumors as MMHs, which was consistent with the 2 previous Doppler ultrasound findings. Surgeons removed the chest tumors by video-assisted thoracoscopic surgery. No treatment was provided for the MMHs. Two tumors of the chest wall were diagnosed as the IHs. There were no significant changes in the hepatic tumors after 32 months of follow-up. Unfortunately, the IH recurred, and the left 5th rib was slightly eroded. It is necessary to include IHs as a potential differential diagnosis for chest wall tumors because early clinical intervention can prevent tumor growth and damage to adjacent structures. The imaging findings of IH show special characteristics. Preoperative imaging evaluation and diagnosis of IH are helpful for safe and effective surgery. Because of the high recurrence rate, complete surgical resection of IH with a sufficient tumor-free margin is recommended. It should be noted that the ribs should also be removed when the surrounding ribs are suspected to have been violated.

Sigmoid Lipoma as an Exceptional Cause of Intussusception and Bowel Obstruction in Adults: A Case Report and Review of Literature

This case report describes a 60-year-old man who presented with acute abdominal pain with marked abdominal distention and red rectal bleeding. A contrast-enhanced abdominal CT scan was performed, which revealed a recto-sigmoid intussusception on lipoma, causing mechanical intestinal obstruction. The patient underwent a partial reduction of the intussusception with partial sigmoid resection and end colostomy. And histologic evaluation confirmed the diagnosis of colonic lipoma. Intussusception of the colon is uncommon in adults and is often associated with malignancy, but other nonmalignant causes such as lipoma may also present with obstructive symptoms, abdominal pain, and rectal bleeding. However, it should be a differential diagnosis of such situations.

Surgical Significance of Variant Anatomy of Inferior Mesenteric Artery and Left Colic Artery: A Computed Tomography Angiographic Study

Introduction: A variation in vessel morphology determines flow dynamics and vascular disease pathogenesis. Definite information on the distinctive anatomical variations of the mesenteric vessels is extremely important for laparoscopic surgical procedures and interventional radiological procedures in the abdominal region. Three-dimensional-computed tomography angiography (3D-CTA) is a less invasive method to evaluate vascular anatomy using a visual tracking method on high-definition images, contrast-enhanced inferior mesenteric artery (IMA) can be traced to its terminal branches beside the colon wall. Subjects and Methods: Abdominal contrast-enhanced computed tomography scan data from 180 patients was retrospectively collected, reconstructed, and analyzed. The origin, length of IMA from origin to the first branch, branching patterns of IMA, and tracking patterns of the ascending branch of left colic artery (LCA), were examined, and their associations with clinical features were analyzed. Results: IMA displayed variations in the level of origin ranging from upper 1/3 of L3 to upper 1/3 of L4, mean length from origin to the first branch was 27.4 ± 7.8 mm. Observed branching patterns of IMA were grouped according to Yada classification: Type 1 (52.2%), Type 2 (15.5%), Type 3 (14.4%), and Type 4 (17.7%). Tracking of the ascending branch of LCA before anastomosis with marginal artery revealed four patterns: Type A LCA pattern in 43.9%; Type B LCA anatomy pattern was (19.4%); Type C LCA anatomy pattern was (20.0%); and Type D LCA anatomy pattern was observed (16.7%). Conclusion: Preoperative understanding of the vascular variations of IMA and LCA can be obtained by 3D-CTA. This may be helpful to surgeons in planning preoperative strategies to prevent iatrogenic injuries.

Deep learning reconstruction vs standard reconstruction for abdominal CT: the influence of BMI.

This study aimed to evaluate the image quality and lesion conspicuity of the deep learning image reconstruction (DLIR) algorithm compared with standard image reconstruction algorithms on abdominal enhanced computed tomography (CT) scanning with a wide range of body mass indexes (BMIs). A total of 112 participants who underwent contrast-enhanced abdominal CT scans were divided into three groups according to BMIs: the 80-kVp group (BMI ≤ 23.9kg/m2), 100-kVp group (BMI 24-28.9kg/m2), and 120-kVp group (BMI ≥ 29kg/m2). All images were reconstructed using filtered back projection (FBP), adaptive statistical iterative reconstruction-V of 50% level (IR), and DLIR at low, medium, and high levels (DL, DM, and DH, respectively). Subjective noise, artifact, overall image quality, and low- and high-contrast hepatic lesion conspicuity were all graded on a 5-point scale. The CT attenuation value (in HU), image noise, and contrast-to-noise ratio (CNR) were quantified and compared. DM and DH improved the qualitative and quantitative parameters compared with FBP and IR for all three BMI groups. DH had the lowest image noise and highest CNR value, while DM had the highest subjective overall image quality and low- and high-contrast lesion conspicuity scores for the three BMI groups. Based on the FBP, the improvement in image quality and lesion conspicuity of DM and DH images was greater in the 80-kVp group than in the 100-kVp and 120-kVp groups. For all BMIs, DLIR improves both image quality and hepatic lesion conspicuity, of which DM would be the best choice to balance both. The study suggests that utilizing DLIR, particularly at the medium level, can significantly enhance image quality and lesion visibility on abdominal CT scans across a wide range of BMIs. • DLIR improved the image quality and lesion conspicuity across a wide range of BMIs. • DLIR at medium level had the highest subjective parameters and lesion conspicuity scores among all reconstruction levels. • On the basis of the FBP, the 80-kVp group had improved image quality and lesion conspicuity more than the 100-kVp and 120-kVp groups.

Acute mesenteric ischemia secondary to superior mesenteric vein thrombosis in a patient with liver cirrhosis: A case report.

Acute mesenteric ischemia due to superior mesenteric vein (SMV) thrombosis is a rare yet potentially life-threatening emergency. Our case report explores this condition in the context of a patient with liver cirrhosis due to Wilson disease. We specifically highlight the complex derangement of the coagulative balance in liver cirrhosis. A 34-year-old female with Wilson disease-related cirrhosis presented with intractable abdominal pain, nausea, and vomiting that showed no response to antispasmodic medication. A contrast-enhanced abdominal computed tomography scan and Doppler ultrasound confirmed an intraluminal filling defect in the SMV, leading to the diagnosis of SMV thrombosis. Prompt anticoagulation, intravenous fluids, and an antibiotic were initiated. Surgical consultation recommended conservative therapy with close monitoring. Over the following 2 days, the patient's condition improved considerably, with almost complete resolution of her symptoms. Genetic testing identified a 4G/4G homozygous genotype of the plasminogen activator inhibitor 1 gene, associated with a higher risk of thrombosis in the vessels of internal organs. After 2 months of sustained anticoagulant therapy, a follow-up contrast-enhanced computed tomography scan revealed near-complete recanalization of the SMV, and the patient remained symptom-free. This case underscores the importance of early detection and treatment of acute mesenteric ischemia in patients with liver cirrhosis, as well as the potential role of genetic factors in thrombosis.

Robotic-assisted partial nephrectomy nightmare: poor clamping and tumor rupture

An 82-year-old Caucasian male patient was referred to our center because of the incidental finding of a nodule in the middle third of the right kidney during a screening abdominal ultrasound. No local or systemic symptom could be associated with the renal mass on initial evaluation. The patient underwent an abdominal contrastenhanced CT scan, which revealed a mass in the outer middle third of the right kidney measuring 4.5 × 3.5 cm, predominantly exophytic, with contact to the collecting system and an enhancement pattern suspicious for primary renal malignancy. Tumor complexity was classified as PADUA score 9 and Renal Score 9x. Clinical stage was cT1bN0M0. Total procedure time was 130 min. Estimated blood loss was 800 mL and warm ischemia time was 24 min. Intraoperative complications were tumor rupture and increased bleeding. The postoperative course was uneventful. Meticulous preoperative planning including contrast enhanced CT with 1 mm thick slices and 3D reconstruction imaging is critical. Comprehensive dissection of the renal hilum must be performed to access the exact number of vessels vascularizing the kidney and to provide adequate ischemia of the renal parenchyma for clean visualization during tumor resection to avoid nightmares such as positive margins and tumor rupture.

Computed tomography in the diagnosis of oncopathology in end-stage renal disease: A case report

BACKGROUND: In recent years, an increasing tendency of oncopathology in patients with chronic kidney disease (CKD) was observed. Clinical data demonstrate an increased risk of malignization in patients with decreased renal function. The cohort study (2022) reported a cumulative incidence of cancer in nephrology patients ranging from 10.8% to 15.3%. A high percentage of stage IV cancers were detected in patients with CKD at the time of diagnosis. In 2022, the American Association for Cancer Research published the results of a Mendelian Randomization Study examining the causal relationship between CKD and the risk of developing 19 local cancers, including renal cell cancer, cervical cancer, leukemia, and colorectal cancer. Several studies found a direct correlation between a decreased glomerular filtration rate and the development of oncopathologies. Therefore, cancer awareness is important in the management of patients with CKD. In patients with end-stage chronic renal disease (ESRD) who are on hemodialysis, X-ray diagnosis with iodine-containing radiopaque agents is possible without additional risk of kidney damage.
 AIM: To demonstratу the role of computed tomography (CT) in the diagnosis of oncopathology in a patient with CKD to attract the attention of physicians to the importance of using advanced diagnostic techniques in patients with CKD.
 METHODS: A clinical case of a 32-year-old patient M. who was hospitalized in the Therapeutic Department of Multidisciplinary City Hospital No. 2 in Astana was presented.
 RESULTS: A patient with ESRD resulting from chronic glomerulonephritis in a hypertensive form complained of dyspnea at rest, cough with difficult sputum, right thoracic pain, general weakness, and weight loss of 8 kg in 1 month. Past medical history showed that the patient was on alternate program hemodialysis for 4 years. Deterioration occurred within 3 months. The patient was examined at the place of residence. CT scan showed signs of tuberculosis of the upper right lobe (?) and lymphadenopathy of intrathoracic and axillary lymph nodes. A neoplasm was not excluded. The patient was consulted by a phthisiatrician, GeneXpert sputum was performed, and tuberculosis was excluded. In dynamics, ultrasound was conducted due to increasing dyspnea. Fluid accumulation in the pericardial and pleural cavities was detected. A pulmonologist assessed the situation as uremic pericarditis, pleurisy on the right side, and right-sided pneumonia in the upper lobe of unclear genesis. Antibacterial therapy was prescribed. Due to a significant deterioration of the condition, the patient went to the city hospital. At admission, respiratory failure, pain syndrome in the chest area, and marked asthenization up to cachexia were observed. Ultrasound of pleural cavities showed free fluid in the pleural cavity on the right (770 ml) and left (110 ml), whereas abdominal ultrasound revealed cavernous hemangiomas of the liver (?), echogenic suspension of the gallbladder, and splenomegaly. Echocardiography showed diffuse hypokinesis of all left ventricular walls. Grade 12 pulmonary hypertension was detected. Systolic function of the left ventricle was moderately decreased. Effusion in the pericardial cavity in the volume of 430 ml and congestion in the inferior vena cava were found. A patient with ESRD was on program hemodialysis for 4 years, which allowed the use of contrast-enhanced X-ray imaging techniques without the risk of additional renal damage. Contrast-enhanced chest CT showed pronounced right-sided pleurisy. Given the presence of foci of contrast agent accumulation in the structure of the parietal pleura, malignancy was not excluded (mesothelioma?). Indolent left-sided pleurisy, segmental and subsegmental compression atelectasis of the right lung, distinct edema and thickening of interlobular septa of both lungs, and single dense foci of I/II, III segments of the left lung up to 4.2 mm in diameter were detected. In addition, chronic bronchitis, pericarditis, and lymphadenopathy of subclavian, intrathoracic, and axillary lymph nodes up to 15.0 mm in diameter (malignancy not excluded) were revealed. Osteosclerosis foci of the Th3 vertebral body measuring 4.75.1 mm was observed. Contrast-enhanced abdominal and retroperineal CT scan showed a focal mass of the IVa segment of the liver measuring 17.315.916.4 mm (malignancy not excluded), chronic calculous cholecystitis, chronic pancreatitis, lymphadenopathy of intra-abdominal para-aortic and mesenteric lymph nodes up to 18.0 mm in size (malignancy not excluded), reduced size of both kidneys (contracted kidneys), and a cystic mass in the left ovary measuring 39.442.034.5 mm (35 HU). Patient was consulted by an oncologist: pleural mesothelioma? Metastasis in the liver? Consultation with a thoracic surgeon to decide on morphological verification was recommended. A biopsy was planned at the place of residence; however, morphological verification of oncopathology was not performed due to the patients lethal outcome.
 CONCLUSIONS: This clinical case of a patient with ESRD on hemodialysis demonstrates the importance of contrast-enhanced CT to diagnose oncopathology.

Automatic bolus tracking in abdominal CT scans with convolutional neural networks.

Bolus tracking can optimize the time delay between contrast injection and diagnostic scan initiation in contrast-enhanced computed tomography (CT), yet the procedure is time-consuming and subject to inter- and intra-operator variances which affect the enhancement levels in diagnostic scans. The objective of the current study is to use artificial intelligence algorithms to fully automate the bolus tracking procedure in contrast-enhanced abdominal CT exams for improved standardization and diagnostic accuracy while providing a simplified imaging workflow. This retrospective study used abdominal CT exams collected under a dedicated Institutional Review Board (IRB). Input data consisted of CT topograms and images with high heterogeneity in terms of anatomy, sex, cancer pathologies, and imaging artifacts acquired with four different CT scanner models. Our method consisted of two sequential steps: (I) automatic locator scan positioning on topograms, and (II) automatic region-of-interest (ROI) positioning within the aorta on locator scans. The task of locator scan positioning is formulated as a regression problem, where the limited amount of annotated data is circumvented using transfer learning. The task of ROI positioning is formulated as a segmentation problem. Our locator scan positioning network offered improved positional consistency compared to a high degree of variance in manual slice positionings, verifying inter-operator variance as a significant source of error. When trained using expert-user ground-truth labels, the locator scan positioning network achieved a sub-centimeter error (9.76±6.78 mm) on a test dataset. The ROI segmentation network achieved a sub-millimeter absolute error (0.99±0.66 mm) on a test dataset. Locator scan positioning networks offer improved positional consistency compared to manual slice positionings and verified inter-operator variance as an important source of error. By significantly reducing operator-related decisions, this method opens opportunities to standardize and simplify the workflow of bolus tracking procedures for contrast-enhanced CT.

Deep learning image reconstruction algorithms in low-dose radiation abdominal computed tomography: assessment of image quality and lesion diagnostic confidence.

The image quality of computed tomography (CT) can be adversely affected by a low radiation dose, and reconstruction algorithms of an appropriate level may be useful in reducing this impact. Eight sets of CT images of a phantom were reconstructed with filtered back projection (FBP); adaptive statistical iterative reconstruction-Veo (ASiR-V) at 30% (AV-30), 50% (AV-50), 80% (AV-80), and 100% (AV-100); and deep learning image reconstruction (DLIR) at low (DL-L), medium (DL-M), and high (DL-H) levels. The noise power spectrum (NPS) and task transfer function (TTF) were measured. Thirty consecutive patients underwent low-dose radiation contrast-enhanced abdominal CT scans that were reconstructed using FBP, AV-30, AV-50, AV-80, and AV-100, and three levels of DLIR. The standard deviation (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the hepatic parenchyma and paraspinal muscle were evaluated. Two radiologists assessed the subjective image quality and lesion diagnostic confidence using a 5-point Likert scale. In the phantom study, both a higher DLIR and ASiR-V strength and a higher radiation dose led less noise. The NPS peak and average spatial frequency of the DLIR algorithms were closer to those of FBP, as the tube current increased and declined as the level of ASiR-V and DLIR strengthened. The NPS average spatial frequency of DL-L were higher than those of AISR-V. In clinical studies, AV-30 demonstrated a higher SD and lower SNR and CNR compared to DL-M and DL-H (P<0.05). For qualitative assessment, DL-M produced the highest qualitative image quality scores, with the exception of overall image noise (P<0.05). The NPS peak, average spatial frequency, and SD were the highest and the SNR, CNR, and subjective scores were the lowest with FBP. Compared with FBP and ASiR-V, DLIR provided better image quality and noise texture both in the phantom and clinical studies, and DL-M maintained the best image quality and lesion diagnostic confidence in low-dose radiation abdominal CT.

Deep Learning to Detect Pancreatic Cystic Lesions on Abdominal Computed Tomography Scans: Development and Validation Study.

Pancreatic cystic lesions (PCLs) are frequent and underreported incidental findings on computed tomography (CT) scans and can evolve to pancreatic cancer-the most lethal cancer, with less than 5 months of life expectancy. The aim of this study was to develop and validate an artificial deep neural network (attention gate U-Net, also named "AGNet") for automated detection of PCLs. This kind of technology can help radiologists to cope with an increasing demand of cross-sectional imaging tests and increase the number of PCLs incidentally detected, thus increasing the early detection of pancreatic cancer. We adapted and evaluated an algorithm based on an attention gate U-Net architecture for automated detection of PCL on CTs. A total of 335 abdominal CTs with PCLs and control cases were manually segmented in 3D by 2 radiologists with over 10 years of experience in consensus with a board-certified radiologist specialized in abdominal radiology. This information was used to train a neural network for segmentation followed by a postprocessing pipeline that filtered the results of the network and applied some physical constraints, such as the expected position of the pancreas, to minimize the number of false positives. Of 335 studies included in this study, 297 had a PCL, including serous cystadenoma, intraductal pseudopapillary mucinous neoplasia, mucinous cystic neoplasm, and pseudocysts . The Shannon Index of the chosen data set was 0.991 with an evenness of 0.902. The mean sensitivity obtained in the detection of these lesions was 93.1% (SD 0.1%), and the specificity was 81.8% (SD 0.1%). This study shows a good performance of an automated artificial deep neural network in the detection of PCL on both noncontrast- and contrast-enhanced abdominal CT scans.

Transarterial Embolization of Ruptured Pancreaticoduodenal Artery Pseudoaneurysm Related to Chronic Pancreatitis

We presented a 67-year-old woman with lightheadedness, diaphoresis, and acute epigastric and right hypochondrium pain, with a past medical history including stage 2 essential hypertension, chronic ischemic cardiomyopathy, and class 1 obesity. An abdominal contrast-enhanced CT scan showed an extensive hematoma (3 × 4 cm2 in size) located intra-abdominally, adjacent to the duodenojejunal area, with hyperdensity around the duodenum, positioned inferior to the pancreas (30-59 HU). Moreover, the CT scan also revealed an enhancing lesion as a pseudoaneurysm of the inferior pancreaticoduodenal artery, measuring 5 × 8 × 8 mm3 with active bleeding and associated hematoma. Following these investigations of the abdominal area, a decision was made to proceed with an endovascular intervention within the interventional radiology department. With the patient under conscious sedation, via a right common femoral artery approach, the superior mesenteric artery was catheterized. While injecting the contrast agent to obtain a better working projection, the pseudoaneurysm ruptured, and acute extravasation of the contrast agent was noted, followed by injection of a mixture of 1 mL Glubran 2 with 2 mL Lipiodol until complete obliteration of the pseudoaneurysm was obtained. The patient was hemodynamically stable at the end of the procedure and was discharged 6 days later in a good condition without active bleeding signs.

Differentiating Benign From Malignant Cystic Renal Masses: A Feasibility Study of Computed Tomography Texture-Based Machine Learning Algorithms.

The Bosniak classification attempts to predict the likelihood of renal cell carcinoma (RCC) among cystic renal masses but is subject to interobserver variability and often requires multiphase imaging. Artificial intelligence may provide a more objective assessment. We applied computed tomography texture-based machine learning algorithms to differentiate benign from malignant cystic renal masses. This is an institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study of 147 patients (mean age, 62.4 years; range, 28-89 years; 94 men) with 144 cystic renal masses (93 benign, 51 RCC); 69 were pathology proven (51 RCC, 18 benign), and 75 were considered benign based on more than 4 years of stability at follow-up imaging. Using a single image from a contrast-enhanced abdominal computed tomography scan, mean, SD, mean value of positive pixels, entropy, skewness, and kurtosis radiomics features were extracted. Random forest, multivariate logistic regression, and support vector machine models were used to classify each mass as benign or malignant with 10-fold cross validation. Receiver operating characteristic curves assessed algorithm performance in the aggregated test data. For the detection of malignancy, sensitivity, specificity, positive predictive value, negative predictive value, and area under the curve were 0.61, 0.87, 0.72, 0.80, and 0.79 for the random forest model; 0.59, 0.87, 0.71, 0.79, and 0.80 for the logistic regression model; and 0.55, 0.86, 0.68, 0.78, and 0.76 for the support vector machine model. Computed tomography texture-based machine learning algorithms show promise in differentiating benign from malignant cystic renal masses. Once validated, these may serve as an adjunct to radiologists' assessments.

Dynamic radiomics for predicting the efficacy of antiangiogenic therapy in colorectal liver metastases.

For patients with advanced colorectal liver metastases (CRLMs) receiving first-line anti-angiogenic therapy, an accurate, rapid and noninvasive indicator is urgently needed to predict its efficacy. In previous studies, dynamic radiomics predicted more accurately than conventional radiomics. Therefore, it is necessary to establish a dynamic radiomics efficacy prediction model for antiangiogenic therapy to provide more accurate guidance for clinical diagnosis and treatment decisions. In this study, we use dynamic radiomics feature extraction method that extracts static features using tomographic images of different sequences of the same patient and then quantifies them into new dynamic features for the prediction of treatmentefficacy. In this retrospective study, we collected 76 patients who were diagnosed with unresectable CRLM between June 2016 and June 2021 in the First Hospital of China Medical University. All patients received standard treatment regimen of bevacizumab combined with chemotherapy in the first-line treatment, and contrast-enhanced abdominal CT (CECT) scans were performed before treatment. Patients with multiple primary lesions as well as missing clinical or imaging information were excluded. Area Under Curve (AUC) and accuracy were used to evaluate model performance. Regions of interest (ROIs) were independently delineated by two radiologists to extract radiomics features. Three machine learning algorithms were used to construct two scores based on the best response and progression-free survival (PFS). For the task that predict the best response patients will achieve after treatment, by using ROC curve analysis, it can be seen that the relative change rate (RCR) feature performed best among all features and best in linear discriminantanalysis (AUC: 0.945 and accuracy: 0.855). In terms of predicting PFS, the Kaplan-Meier plots suggested that the score constructed using the RCR features could significantly distinguish patients with good response from those with poor response (Two-sided P<0.0001 for survival analysis). This study demonstrates that the application of dynamic radiomics features can better predict the efficacy of CRLM patients receiving antiangiogenic therapy compared with conventional radiomics features. It allows patients to have a more accurate assessment of the effect of medical treatment before receiving treatment, and this assessment method is noninvasive, rapid, and less expensive. Dynamic radiomics model provides stronger guidance for the selection of treatment options and precision medicine.

PS-R03-5: HYPOTENSIVE AND HYPERGLYCEMIC EFFECTS OF DIAZOXIDE IN A CASE OF INSULINOMA

Case report: We report the case of sporadic insulinoma in a 70-year-old female with breast cancer and hypertension treated by irbesartan 100 mg and benidipine 8 mg, who presented with a 1-month history of episodic tremulousness, diaphoresis, increased hunger, confusion and fainting. Initial laboratory investigations showed low blood glucose (21 mg/dL) and high blood insulin (107 μU/mL) levels. The hypoglycemic symptoms were relieved greatly by glucose administration and Whipple's triad for insulinoma was met. An abdominal contrast-enhanced computed tomography scan showed a 12 mm, small, well demarcated, heterogeneously enhancing lesion within the tail of pancreas without dilatation of pancreatic duct. The site also showed a well-defined accumulation of boundaries on PET-CT. Patient was diagnosed with insulinoma. Since Patient did not initially wish to undergo surgery, blood glucose control was performed by taking diazoxide 225 mg, gradually reduced to 50 mg. Before and after taking diazoxide, blood glucose increased from 75 ± 40 mg/dL to 124 ± 35 mg/dL significantly (p &lt; 0.05). On the other hand, blood pressure was significantly reduced from 141 ± 3/78 ± 3 mmHg to 126 ± 3/75 ± 3 mmHg. Benidipine was withdrawn to about 130/80 mmHg. Then, Patient changed her mind and underwent laparoscopic caudal pancreatic resection. Histopathological examination of the pancreatic mass confirmed neuroendocrine tumor (insulinoma). Patient had an uneventful recovery. Blood pressure re-increased above 140/90 mmHg and benidipine was resumed. Although diazoxide suppresses insulin secretion in the pancreas due to its KATP channel opening action and improves hypoglycemic attacks with insulinoma, it also acts on the KATP channel of vascular smooth muscle and show a hypotensive effect. It is important to pay close attention not only to blood glucose but also to blood pressure fluctuations when using diazoxide.

Changes in clinical and CT manifestations related to liver abscesses in patients with vs. without basic diabetes mellitus before and after CT-guided interventional therapy: An observational study

PurposeTo explore differences in the changes of clinical and CT manifestations related to liver abscess before and after CT-guided interventional therapy between patients with and without Diabetes Mellitus (DM). Materials and methodsFifty-eight consecutive patients with liver abscesses were retrospectively enrolled in this study. All patients underwent upper abdominal contrast-enhanced CT scans before and after CT-guided interventional therapy. They were divided into two groups including the DM group (n=30) and the Non-DM group (n=28) if the liver abscess occurred in patients with and without DM, respectively. The changes in the clinical and CT manifestations related to liver abscess after CT-guided interventional therapy in both groups were statistically analyzed. ResultsAfter CT-guided interventional therapy, the length of hospital stay, white blood cell recovery time and drainage tube removal time in the DM group were longer than in the Non-DM group (all p-values < 0.05). The incidence of postoperative complications in the DM group was higher than in the Non-DM group (p < 0.05). As shown on CT, the postoperative reduced percentage of maximum diameter of abscess cavity and the reduction rate of edema band surrounding the liver abscess in the DM group were smaller than in the Non-DM group (both p-values < 0.05). The time intervals of the previous characteristic changes on CT before and after interventional therapy in the DM group were longer than in the Non-DM group (all p-values < 0.05). ConclusionsThe liver abscesses patients with DM could not have a faster recovery and better therapeutic effect than those without DM after the CT-guided interventional therapy.

Automated CT pancreas segmentation for acute pancreatitis patients by combining a novel object detection approach and U-Net

Acute pancreatitis is an inflammatory disorder of the pancreas. Medical imaging, such as computed tomography (CT), has been widely used to detect volume changes in the pancreas for acute pancreatitis diagnosis. Many pancreas segmentation methods have been proposed but no methods for pancreas segmentation from acute pancreatitis patients. The segmentation of an inflamed pancreas is more challenging than the normal pancreas due to the following two reasons. 1) The inflamed pancreas invades surrounding organs and causes blurry boundaries. 2) The inflamed pancreas has higher shape, size, and location variability than the normal pancreas. To overcome these challenges, we propose an automated CT pancreas segmentation approach for acute pancreatitis patients by combining a novel object detection approach and U-Net. Our approach includes a detector and a segmenter. Specifically, we develop an FCN-guided region proposal network (RPN) detector to localize the pancreatitis regions. The detector first uses a fully convolutional network (FCN) to reduce the background interference of medical images and generates a fixed feature map containing the acute pancreatitis regions. Then the RPN is employed on the feature map to precisely localize the acute pancreatitis regions. After obtaining the location of pancreatitis, the U-Net segmenter is used on the cropped image according to the bounding box. The proposed approach is validated using a collected clinical dataset with 89 abdominal contrast-enhanced 3D CT scans from acute pancreatitis patients. Compared with other start-of-the-art approaches for normal pancreas segmentation, our method achieves better performance on both localization and segmentation in acute pancreatitis patients.

A spectrum of findings on computed tomography in paediatric abdominal and pelvic tumours in a Ghanaian teaching hospital.

To review the Computed Tomography( CT )features of pediatric oncological patients with abdominal and pelvic tumours and correlate these findings with their histopathological diagnosis. This was a retrospective cross-sectional facility-based study. This study was conducted in the Pediatric Oncology Unit and Radiology Department of the Korle Bu Teaching Hospital. Fifty-six pediatric oncology patients with contrast-enhanced abdominal and pelvic CT scans. The abdominal and pelvic CT scans findings, patient biodata, and histopathology reports of oncology patients over four years were reviewed. Simple descriptive statistics using frequency distribution, percentages, means, and standard deviation were used to describe the various variables and presented tables. The four commonest tumours were nephroblastoma, neuroblastoma, lymphoma, and hepatoblastoma. The mean age at diagnosis was 4.8 years, with a slightly higher male predominance. The majority of the tumours were extremely large at presentation. Overall, the CT - histopathology concordance was 79.2%. Abdominal and pelvic CT scans play an important role in the diagnostic workup of pediatric malignancies by ensuring early and accurate diagnosis of these tumours. None declared.