Protein tyrosine phosphatase 69D is a substrate of protein O-mannosyltransferases 1-2 that is required for the wiring of sensory axons in Drosophila.

Mutations in protein O-mannosyltransferases (POMTs) result in severe brain defects and congenital muscular dystrophies characterized by abnormal glycosylation of α-dystroglycan (α-Dg). However, neurological phenotypes of POMT mutants are not well understood, and the functional substrates of POMTs other than α-Dg remain unknown. Using a Drosophila model, here we reveal that Dg alone cannot account for the phenotypes of POMT mutants, and identify Protein tyrosine phosphatase 69D (PTP69D) as a gene interacting with POMTs in producing the abdomen rotation phenotype. Using RNAi-mediated knockdown, mutant alleles, and a dominant-negative form of PTP69D, we reveal that PTP69D is required for the wiring of larval sensory axons. We also found that PTP69D and POMT genes interact in this process, and that their interactions lead to complex synergistic or antagonistic effects on axon wiring phenotypes, depending on the mode of genetic manipulation. Using glycoproteomic approaches, we further characterized the glycosylation of the PTP69D transgenic construct expressed in genetic strains with different levels of POMT activity. We found that the PTP69D construct carries many O-linked mannose modifications when expressed in Drosophila with wild-type or ectopically upregulated expression of POMTs. These modifications were absent in POMT mutants, suggesting that PTP69D is a substrate of POMT-mediated O-mannosylation. Taken together, our results indicate that PTP69D is a novel functional substrate of POMTs that is required for axon connectivity. This mechanism of POMT-mediated regulation of receptor-type protein tyrosine phosphatase functions could potentially be conserved in mammals and may shed new light on the etiology of neurological defects in muscular dystrophies.

Abdominal Diffusion-Weighted MRI With Simultaneous Multi-Slice Acquisition: Agreement and Reproducibility of Apparent Diffusion Coefficients Measurements.

BACKGROUND: Simultaneous multi-slice diffusion-weighted imaging (SMS-DWI) can shorten acquisition time in abdominal imaging. PURPOSE: To investigate the agreement and reproducibility of apparent diffusion coefficient (ADC) from abdominal SMS-DWI acquired with different vendors and different breathing schemes. STUDY TYPE: Prospective. SUBJECTS: Twenty volunteers and 10 patients. FIELD STRENGTH/SEQUENCE: 3.0 T, SMS-DWI with a diffusion-weighted echo-planar imaging sequence. ASSESSMENT: SMS-DWI was acquired using breath-hold and free-breathing techniques in scanners from two vendors, yielding four scans in each participant. Average ADC values were measured in the liver, pancreas, spleen, and both kidneys. Non-normalized ADC and ADCs normalized to the spleen were compared between vendors and breathing schemes. STATISTICAL TESTS: Paired t-test or Wilcoxon signed rank test; intraclass correlation coefficient (ICC); Bland-Altman method; coefficient of variation (CV) analysis; significance level: P < 0.05. RESULTS: Non-normalized ADCs from the four SMS-DWI scans did not differ significantly in the spleen (P = 0.262, 0.330, 0.166, 0.122), right kidney (P = 0.167, 0.538, 0.957, 0.086), and left kidney (P = 0.182, 0.281, 0.504, 0.405), but there were significant differences in the liver and pancreas. For normalized ADCs, there were no significant differences in the liver (P = 0.315, 0.915, 0.198, 0.799), spleen (P = 0.815, 0.689, 0.347, 0.423), pancreas (P = 0.165, 0.336, 0.304, 0.584), right kidney (P = 0.165, 0.336, 0.304, 0.584), and left kidney (P = 0.496, 0.304, 0.443, 0.371). Inter-reader agreements of non-normalized ADCs were good to excellent (ICCs ranged from 0.861 to 0.983), and agreement and reproducibility were good to excellent depending on anatomic location (CVs ranged from 3.55% to 13.98%). Overall CVs for abdominal ADCs from the four scans were 6.25%, 7.62%, 7.08, and 7.60%. DATA CONCLUSION: The normalized ADCs from abdominal SMS-DWI may be comparable between different vendors and breathing schemes, showing good agreement and reproducibility. ADC changes above approximately 8% may potentially be considered as a reliable quantitative biomarker to assess disease or treatment-related changes. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

Large variation in radiation dose for routine abdomen CT: reasons for excess and easy tips for reduction.

OBJECTIVE: To characterize the use and impact of radiation dose reduction techniques in actual practice for routine abdomen CT. METHODS: We retrospectively analyzed consecutive routine abdomen CT scans in adults from a large dose registry, contributed by 95 hospitals and imaging facilities. Grouping exams into deciles by, first, patient size, and second, size-adjusted dose length product (DLP), we summarized dose and technical parameters and estimated which parameters contributed most to between-protocols dose variation. Lastly, we modeled the total population dose if all protocols with mean size-adjusted DLP above 433 or 645 mGy-cm were reduced to these thresholds. RESULTS: A total of 748,846 CTs were performed using 1033 unique protocols. When sorted by patient size, patients with larger abdominal diameters had increased dose and effective mAs (milliampere seconds), even after adjusting for patient size. When sorted by size-adjusted dose, patients in the highest versus the lowest decile in size-adjusted DLP received 6.4 times the average dose (1680 vs 265 mGy-cm) even though diameter was no different (312 vs 309 mm). Effective mAs was 2.1-fold higher, unadjusted CTDIvol 2.9-fold, and phase 2.5-fold for patients in the highest versus lowest size-adjusted DLP decile. There was virtually no change in kV (kilovolt). Automatic exposure control was widely used to modulate mAs, whereas kV modulation was rare. Phase was the strongest driver of between-protocols variation. Broad adoption of optimized protocols could result in total population dose reductions of 18.6-40%. CONCLUSION: There are large variations in radiation doses for routine abdomen CT unrelated to patient size. Modification of kV and single-phase scanning could result in substantial dose reduction. CLINICAL RELEVANCE: Radiation dose-optimization techniques for routine abdomen CT are routinely under-utilized leading to higher doses than needed. Greater modification of technical parameters and number of phases could result in substantial reduction in radiation exposure to patients. KEY POINTS: • Based on an analysis of 748,846 routine abdomen CT scans in adults, radiation doses varied tremendously across patients of the same size and optimization techniques were routinely under-utilized. • The difference in observed dose was due to variation in technical parameters and phase count. Automatic exposure control was commonly used to modify effective mAs, whereas kV was rarely adjusted for patient size. Routine abdomen CT should be performed using a single phase, yet multi-phase was common. • kV modulation by patient size and restriction to a single phase for routine abdomen indications could result in substantial reduction in radiation doses using well-established dose optimization approaches.

Radiomics in differential diagnosis of Wilms tumor and neuroblastoma with adrenal location in children.

OBJECTIVES: Machine learning methods can be applied successfully to various medical imaging tasks. Our aim with this study was to build a robust classifier using radiomics and clinical data for preoperative diagnosis of Wilms tumor (WT) or neuroblastoma (NB) in pediatric abdominal CT. MATERIAL AND METHODS: This is a single-center retrospective study approved by the Institutional Ethical Board. CT scans of consecutive patients diagnosed with WT or NB admitted to our hospital from January 2005 to December 2021 were evaluated. Three distinct datasets based on clinical centers and CT machines were curated. Robust, non-redundant, high variance, and relevant radiomics features were selected using data science methods. Clinically relevant variables were integrated into the final model. Dice score for similarity of tumor ROI, Cohen's kappa for interobserver agreement among observers, and AUC for model selection were used. RESULTS: A total of 147 patients, including 90 WT (mean age 34.78 SD: 22.06 months; 43 male) and 57 NB (mean age 23.77 SD:22.56 months; 31 male), were analyzed. After binarization at 24 months cut-off, there was no statistically significant difference between the two groups for age (p = .07) and gender (p = .54). CT clinic radiomics combined model achieved an F1 score of 0.94, 0.93 accuracy, and an AUC 0.96. CONCLUSION: In conclusion, the CT-based clinic-radiologic-radiomics combined model could noninvasively predict WT or NB preoperatively. Notably, that model correctly predicted two patients, which none of the radiologists could correctly predict. This model may serve as a noninvasive preoperative predictor of NB/WT differentiation in CT, which should be further validated in large prospective models. CLINICAL RELEVANCE STATEMENT: CT-based clinic-radiologic-radiomics combined model could noninvasively predict Wilms tumor or neuroblastoma preoperatively. KEY POINTS: • CT radiomics features can predict Wilms tumor or neuroblastoma from abdominal CT preoperatively. • Integrating clinic variables may further improve the performance of the model. • The performance of the combined model is equal to or greater than human readers, depending on the lesion size.

Automated abdominal CT contrast phase detection using an interpretable and open-source artificial intelligence algorithm.

OBJECTIVES: To develop and validate an open-source artificial intelligence (AI) algorithm to accurately detect contrast phases in abdominal CT scans. MATERIALS AND METHODS: Retrospective study aimed to develop an AI algorithm trained on 739 abdominal CT exams from 2016 to 2021, from 200 unique patients, covering 1545 axial series. We performed segmentation of five key anatomic structures-aorta, portal vein, inferior vena cava, renal parenchyma, and renal pelvis-using TotalSegmentator, a deep learning-based tool for multi-organ segmentation, and a rule-based approach to extract the renal pelvis. Radiomics features were extracted from the anatomical structures for use in a gradient-boosting classifier to identify four contrast phases: non-contrast, arterial, venous, and delayed. Internal and external validation was performed using the F1 score and other classification metrics, on the external dataset "VinDr-Multiphase CT". RESULTS: The training dataset consisted of 172 patients (mean age, 70 years ± 8, 22% women), and the internal test set included 28 patients (mean age, 68 years ± 8, 14% women). In internal validation, the classifier achieved an accuracy of 92.3%, with an average F1 score of 90.7%. During external validation, the algorithm maintained an accuracy of 90.1%, with an average F1 score of 82.6%. Shapley feature attribution analysis indicated that renal and vascular radiodensity values were the most important for phase classification. CONCLUSION: An open-source and interpretable AI algorithm accurately detects contrast phases in abdominal CT scans, with high accuracy and F1 scores in internal and external validation, confirming its generalization capability. CLINICAL RELEVANCE STATEMENT: Contrast phase detection in abdominal CT scans is a critical step for downstream AI applications, deploying algorithms in the clinical setting, and for quantifying imaging biomarkers, ultimately allowing for better diagnostics and increased access to diagnostic imaging. KEY POINTS: Digital Imaging and Communications in Medicine labels are inaccurate for determining the abdominal CT scan phase. AI provides great help in accurately discriminating the contrast phase. Accurate contrast phase determination aids downstream AI applications and biomarker quantification.

Deep learning for automatic bowel-obstruction identification on abdominal CT.

RATIONALE AND OBJECTIVES: Automated evaluation of abdominal computed tomography (CT) scans should help radiologists manage their massive workloads, thereby leading to earlier diagnoses and better patient outcomes. Our objective was to develop a machine-learning model capable of reliably identifying suspected bowel obstruction (BO) on abdominal CT. MATERIALS AND METHODS: The internal dataset comprised 1345 abdominal CTs obtained in 2015-2022 from 1273 patients with suspected BO; among them, 670 were annotated as BO yes/no by an experienced abdominal radiologist. The external dataset consisted of 88 radiologist-annotated CTs. We developed a full preprocessing pipeline for abdominal CT comprising a model to locate the abdominal-pelvic region and another model to crop the 3D scan around the body. We built, trained, and tested several neural-network architectures for the binary classification (BO, yes/no) of each CT. F1 and balanced accuracy scores were computed to assess model performance. RESULTS: The mixed convolutional network pretrained on a Kinetics 400 dataset achieved the best results: with the internal dataset, the F1 score was 0.92, balanced accuracy 0.86, and sensitivity 0.93; with the external dataset, the corresponding values were 0.89, 0.89, and 0.89. When calibrated on sensitivity, this model produced 1.00 sensitivity, 0.84 specificity, and an F1 score of 0.88 with the internal dataset; corresponding values were 0.98, 0.76, and 0.87 with the external dataset. CONCLUSION: The 3D mixed convolutional neural network developed here shows great potential for the automated binary classification (BO yes/no) of abdominal CT scans from patients with suspected BO. CLINICAL RELEVANCE STATEMENT: The 3D mixed CNN automates bowel obstruction classification, potentially automating patient selection and CT prioritization, leading to an enhanced radiologist workflow. KEY POINTS: • Bowel obstruction's rising incidence strains radiologists. AI can aid urgent CT readings. • Employed 1345 CT scans, neural networks for bowel obstruction detection, achieving high accuracy and sensitivity on external testing. • 3D mixed CNN automates CT reading prioritization effectively and speeds up bowel obstruction diagnosis.

Radiomics in the characterization of lipid-poor adrenal adenomas at unenhanced CT: time to look beyond usual density metrics.

OBJECTIVES: In this study, we developed a radiomic signature for the classification of benign lipid-poor adenomas, which may potentially help clinicians limit the number of unnecessary investigations in clinical practice. Indeterminate adrenal lesions of benign and malignant nature may exhibit different values of key radiomics features. METHODS: Patients who had available histopathology reports and a non-contrast-enhanced CT scan were included in the study. Radiomics feature extraction was done after the adrenal lesions were contoured. The primary feature selection and prediction performance scores were calculated using the least absolute shrinkage and selection operator (LASSO). To eliminate redundancy, the best-performing features were further examined using the Pearson correlation coefficient, and new predictive models were created. RESULTS: This investigation covered 50 lesions in 48 patients. After LASSO-based radiomics feature selection, the test dataset's 30 iterations of logistic regression models produced an average performance of 0.72. The model with the best performance, made up of 13 radiomics features, had an AUC of 0.99 in the training phase and 1.00 in the test phase. The number of features was lowered to 5 after performing Pearson's correlation to prevent overfitting. The final radiomic signature trained a number of machine learning classifiers, with an average AUC of 0.93. CONCLUSIONS: Including more radiomics features in the identification of adenomas may improve the accuracy of NECT and reduce the need for additional imaging procedures and clinical workup, according to this and other recent radiomics studies that have clear points of contact with current clinical practice. CLINICAL RELEVANCE STATEMENT: The study developed a radiomic signature using unenhanced CT scans for classifying lipid-poor adenomas, potentially reducing unnecessary investigations that scored a final accuracy of 93%. KEY POINTS: • Radiomics has potential for differentiating lipid-poor adenomas and avoiding unnecessary further investigations. • Quadratic mean, strength, maximum 3D diameter, volume density, and area density are promising predictors for adenomas. • Radiomics models reach high performance with average AUC of 0.95 in the training phase and 0.72 in the test phase.

Multi-reader multiparametric DECT study evaluating different strengths of iterative and deep learning-based image reconstruction techniques.

OBJECTIVES: To perform a multi-reader comparison of multiparametric dual-energy computed tomography (DECT) images reconstructed with deep-learning image reconstruction (DLIR) and standard-of-care adaptive statistical iterative reconstruction-V (ASIR-V). METHODS: This retrospective study included 100 patients undergoing portal venous phase abdominal CT on a rapid kVp switching DECT scanner. Six reconstructed DECT sets (ASIR-V and DLIR, each at three strengths) were generated. Each DECT set included 65 keV monoenergetic, iodine, and virtual unenhanced (VUE) images. Using a Likert scale, three radiologists performed qualitative assessments for image noise, contrast, small structure visibility, sharpness, artifact, and image preference. Quantitative assessment was performed by measuring attenuation, image noise, and contrast-to-noise ratios (CNR). For the qualitative analysis, Gwet's AC2 estimates were used to assess agreement. RESULTS: DECT images reconstructed with DLIR yielded better qualitative scores than ASIR-V images except for artifacts, where both groups were comparable. DLIR-H images were rated higher than other reconstructions on all parameters (p-value < 0.05). On quantitative analysis, there was no significant difference in the attenuation values between ASIR-V and DLIR groups. DLIR images had higher CNR values for the liver and portal vein, and lower image noise, compared to ASIR-V images (p-value < 0.05). The subgroup analysis of patients with large body habitus (weight ≥ 90 kg) showed similar results to the study population. Inter-reader agreement was good-to-very good overall. CONCLUSION: Multiparametric post-processed DECT datasets reconstructed with DLIR were preferred over ASIR-V images with DLIR-H yielding the highest image quality scores. CLINICAL RELEVANCE STATEMENT: Deep-learning image reconstruction in dual-energy CT demonstrated significant benefits in qualitative and quantitative image metrics compared to adaptive statistical iterative reconstruction-V. KEY POINTS: Dual-energy CT (DECT) images reconstructed using deep-learning image reconstruction (DLIR) showed superior qualitative scores compared to adaptive statistical iterative reconstruction-V (ASIR-V) reconstructed images, except for artifacts where both reconstructions were rated comparable. While there was no significant difference in attenuation values between ASIR-V and DLIR groups, DLIR images showed higher contrast-to-noise ratios (CNR) for liver and portal vein, and lower image noise (p value < 0.05). Subgroup analysis of patients with large body habitus (weight ≥ 90 kg) yielded similar findings to the overall study population.

Outcomes of Prolonged Open Abdomen in Children.

INTRODUCTION: We sought to better characterize outcomes in pediatric patients requiring open abdomen for instability with ongoing resuscitation, second look surgery, or left in discontinuity or congenital or acquired loss of domain that may lead to prolonged open abdomen (POA) or difficulties in successful abdominal wall closure. METHODS: We performed a single-institution retrospective review of patients aged less or equal to 18 years who presented to our institution from 2015 to 2022. We defined POA as requiring three or more surgeries prior to abdominal wall closure. Descriptive statistics were performed using median and interquartile range. RESULTS: Median age was 15 years (interquartile range 0-6 years), 46% female, and 69% White. Survival rate was 93% for the entire cohort. The most common indication for open abdomen was second look/discontinuity 22/41 (54%). The most common temporary abdominal wall closure was wound vac (43%). Fifty eight percent patients achieved primary tissue closure, the remaining required mesh. Of the 42 patients, 25 required POA. They had increasing rate of secondary infections at 56% compared to 44% (P = 0.17). The groups were further divided into indications for open abdomen including ongoing resuscitation, second look/discontinuity, and loss of domain with similar outcomes. CONCLUSIONS: In the largest series of long-term outcomes in pediatric patients with an open abdomen, we found that a majority of children were able to be primarily closed without mesh despite the number of surgeries required. Further studies require a protocolized approach to improve the long-term outcomes of these patients.

Negative Pressure Wound Therapy After Intestinal Anastomosis: A Risk Factor Analysis for Dehiscence.

INTRODUCTION: Negative pressure wound therapy (NPWT) is part of the temporary abdominal closure in the treatment of patients with traumatic, inflammatory, or vascular disease. However, the use of NPWT when performing an intestinal anastomosis has been controversial. This study aimed to describe the patients managed with NPWT therapy and identify the risk factors for anastomotic dehiscence when intestinal anastomosis was performed. METHODS: A single-center cohort study with prospectively collected databases was performed. Patients who required NPWT therapy from January 2014 to December 2018 were included. Patients were stratified according to the performance of intestinal anastomosis and according to the presence of dehiscence. Bivariate and multivariate analyses were performed for anastomotic dehiscence and mortality. RESULTS: A total of 97 patients were included. Median age was 52 y old [interquartile range 24.5-70]. Male patients corresponded to 75.6% (n = 34) of the population. Delayed fascial closure was performed in 80% (n = 36). The risk of anastomotic dehiscence was higher in females (odds ratio (OR) 11.52 [confidence interval (CI) 1.29-97.85], P = 0.030), delayed fascial closure (OR 18.18 [CI 2.02-163.5], P = 0.010) and use of vasopressors (OR 12.04 [CI 1.22-118.47], P = 0.033). NPWT pressures >110 mmHg were evidenced in the dehiscence group with statistically significant value (OR 1.2 [0.99-2.26] p 0.04) CONCLUSIONS: There is still controversy in the use of NPWT when performing intestinal anastomosis. According to our data, the risk of dehiscence is higher in females, delayed fascial closure, use of vasopressors, and NPWT pressures >110 MMHG.

Temporary abdominal closure in oncological patients: Surgical characteristics and implications.

BACKGROUND AND OBJECTIVES: In critically ill patients, temporary abdominal closure (TAC) is utilized for conditions like abdominal compartment syndrome risk, gross abdominal contamination, and intestinal loop viability doubts. TAC techniques aim to safeguard abdominal contents, drain intraperitoneal fluids, and minimize fascia and skin damage. Our goal is to outline clinical characteristics and surgical outcomes in oncological patients undergoing peritoneostomy. METHODS: Patients undergoing TAC with vacuum therapy at a tertiary oncological center were studied, with data sourced from an institutional database. RESULTS: Forty-seven patients (54.3% female), with an average age of 63.1 ± 12.3 years, were included in the study. The primary tumor site was predominantly gastrointestinal (78.2%). Patients presented systemic signs of chronic disease, reflected by a mean body mass index of 18.2 ± 7.6 kg/m², hemoglobin level of 9.2 ± 1.8 g/dL, and albumin level of 2.3 ± 0.6 g/dL. Additionally, most patients had a low-performance status (53% Eastern Cooperative Oncology Group 1/2, 44.8% Karnofsky score ≤80, and 61.2% Charlson Comorbidity Index ≥6). Emergency surgical complications were the main reasons for initial surgery (68%), with the majority attributed to fecal peritonitis (65.9%). Only 14.8% of patients achieved complete abdominal closure with an average of 24.8 days until closure. The in-hospital mortality rate was 85.2%. CONCLUSION: TAC is an alternative for oncological patients with surgical complications, but it carries a high mortality rate due to the compromised conditions of the patients.

Increasing Use of Prophylactic Open Abdomen Therapy With Vacuum Assisted Wound Closure and Mesh Mediated Fascial Traction After Repair of Ruptured Abdominal Aortic Aneurysm.

OBJECTIVE: Open abdomen therapy (OAT) is commonly used to prevent or treat abdominal compartment syndrome (ACS) in patients with ruptured abdominal aortic aneurysms (rAAAs). This study aimed to evaluate the incidence, treatment, and outcomes of OAT after rAAA from 2006 to 2021. Investigating data on resuscitation fluid, weight gain, and cumulative fluid balance could provide a more systematic approach to determining the timing of safe abdominal closure. METHODS: This was a single centre observational cohort study. The study included all patients treated for rAAA followed by OAT from October 2006 to December 2021. RESULTS: Seventy-two of the 244 patients who underwent surgery for rAAA received OAT. The mean age was 72 ± 7.85 years, and most were male (n = 61, 85%). The most frequent comorbidities were cardiac disease (n = 31, 43%) and hypertension (n = 31, 43%). Fifty-two patients (72%) received prophylactic OAT, and 20 received OAT for ACS (28%). There was a 25% mortality rate in the prophylactic OAT group compared with the 50% mortality in those who received OAT for ACS (p = .042). The 58 (81%) patients who survived until closure had a median of 12 (interquartile range [IQR] 9, 16.5) days of OAT and 5 (IQR 4, 7) dressing changes. There was one case of colocutaneous fistula and two cases of graft infection. All 58 patients underwent successful abdominal closure, with 55 (95%) undergoing delayed primary closure. In hospital survival was 85%. Treatment trends over time showed the increased use of prophylactic OAT (p ≤ .001) and fewer ACS cases (p = .03) assessed by Fisher's exact test. In multivariable regression analysis fluid overload and weight reduction predicted 26% of variability in time to closure. CONCLUSION: Prophylactic OAT after rAAA can be performed safely, with a high rate of delayed primary closure even after long term treatment.

Small bowel intramural hematoma caused by warfarin: case report and literature review.

BACKGROUND: Intramural hematoma of the small bowel is a rare yet acute gastrointestinal condition typically linked with impaired coagulation function, often posing diagnostic challenges. It is principally encountered in patients undergoing prolonged anticoagulant therapy, specifically warfarin. CASE PRESENTATION: We reported a case of intramural hematoma associated with warfarin use. The patient was admitted to hospital with abdominal pain and had received anticoagulant therapy with warfarin 2.5 mg/day for 4 years. Laboratory examination showed decreased coagulation function, abdominal CT showed obvious thickening and swelling of part of the jejunal wall, and abdominal puncture found no gastroenteric fluid or purulent fluid. We treated the patient with vitamin K and fresh frozen plasma. The patient was discharged after the recovery of coagulation function. Then we undertaook a comprehensive review of relevant case reports to extract shared clinical features and effective therapeutic strategies. CONCLUSION: Our analysis highlights that hematoma in the small intestinal wall caused by warfarin overdose often presents as sudden and intense abdominal pain, laboratory tests suggest reduced coagulation capacity, and imaging often shows thickening of the intestinal wall. Intravenous vitamin K and plasma supplementation are effective non-surgical strategies. Nevertheless, in instances of severe obstruction and unresponsive hemostasis, surgical resection of necrotic intestinal segments may be necessary. In the cases we reported, we avoided surgery by closely monitoring the coagulation function. Therefore, we suggest that identifying and correcting the impaired coagulation status of patient is essential for timely and appropriate treatment.

Evaluation of geographic variations in appendicectomy outcomes within Western Australia assessing the impact of surgical wait times and rate of negative appendicectomies in both urban and rural locations statewide.

PURPOSE: Surgery wait times after diagnosis of appendicitis are an important factor influencing the success of a patient's treatment. The proposed study will be a quantitative multicenter retrospective cohort design with the primary aim of assessing the difference between appendicectomy wait times between rural and urban hospitals in Western Australia and the effect of this on operative outcomes. Selected outcome measures will be examined by time from initial presentation at an emergency department to the patient being diagnosed and then time of diagnosis to surgery being performed. The secondary aim is to compare rates of negative appendicectomies between hospitals. METHODS: Appendicectomy patients will be identified from operating room register by medical student data collectors; then, each respective hospital's emergency room data collection will subsequently be accessed to complete case report forms based on demographics and clinical findings, pre-operative investigations, and management and follow-up. Case report forms with > 95% completeness will be accepted for pooled analysis. The expected duration of retrospective data collection will be 8 months. This study RGS6483 has received HREC approval by the Royal Perth Hospital HREC Ethics Committee, with a waiver of consent obtained and the HREC was notified of amendments to the protocol made on April 21, 2024. Dissemination of results. Data will be collected and stored online through a secure server running the Research Electronic Data Capture (REDCap) web application. No patient-identifiable data will be entered into the system. Results will subsequently be shared via scientific journal publication and presentation at relevant meetings.

Evaluation of acute terminal ileitis in children before and during the COVID-19 pandemic.

OBJECTIVES: The aim of this study was to examine the clinical features of acute terminal ileitis in children and evaluate its rate before and during the COVID-19 pandemic. METHODS: This retrospective study was performed in our pediatric emergency department between 2018 and 2022. The records of 5363 patients who required abdominal imaging due to acute abdomen were analyzed, and 143 patients with terminal ileitis were included. The rate and etiological causes were compared during and before the COVID-19 pandemic. RESULTS: The rate of acute terminal ileitis has increased over the years. The fastest increase was in 2021, when the COVID-19 pandemic was experienced. While 59 (41.2%) patients showed acute nonspecific ileitis, the most common etiologic cause that could be identified was acute gastroenteritis. It was determined that multisystem inflammatory syndrome in children was among the causes of ileitis after the COVID-19 pandemic and was one of the top three causes. CONCLUSIONS: Acute terminal ileitis, which has many etiologies, is one of the rare radiological findings in acute abdominal pain. Examination and laboratory findings are not specific. Guidelines are needed for the investigation of the underlying etiology of acute terminal ileitis in children. The incidence of acute terminal ileitis is increasing, and the increase has been found to be faster after the COVID-19 pandemic.

Towards more precise automatic analysis: a systematic review of deep learning-based multi-organ segmentation.

Accurate segmentation of multiple organs in the head, neck, chest, and abdomen from medical images is an essential step in computer-aided diagnosis, surgical navigation, and radiation therapy. In the past few years, with a data-driven feature extraction approach and end-to-end training, automatic deep learning-based multi-organ segmentation methods have far outperformed traditional methods and become a new research topic. This review systematically summarizes the latest research in this field. We searched Google Scholar for papers published from January 1, 2016 to December 31, 2023, using keywords "multi-organ segmentation" and "deep learning", resulting in 327 papers. We followed the PRISMA guidelines for paper selection, and 195 studies were deemed to be within the scope of this review. We summarized the two main aspects involved in multi-organ segmentation: datasets and methods. Regarding datasets, we provided an overview of existing public datasets and conducted an in-depth analysis. Concerning methods, we categorized existing approaches into three major classes: fully supervised, weakly supervised and semi-supervised, based on whether they require complete label information. We summarized the achievements of these methods in terms of segmentation accuracy. In the discussion and conclusion section, we outlined and summarized the current trends in multi-organ segmentation.

Diagnosis and treatment of epiploic appendagitis in a Middle Eastern country: An observational retrospective analysis of 156 cases.

BACKGROUND: Epiploic appendagitis (EPA) is an uncommon emergency surgical condition that causes acute abdominal pain, rendering a list of differential diagnoses. Therefore, careful examination and imaging tools are required. EPA is a self-limiting condition that can be resolved in 1-2 weeks and rarely needs surgical intervention. Its low incidence makes EPA less well-known among the public and some medical professionals, and it is frequently under-diagnosed. We aimed to explore the incidence, clinical presentation, modalities of imaging to diagnose and options for treating EPA. METHODS: An observational retrospective analysis was conducted between 2016 and 2022 at a tertiary hospital in an Arab Middle Eastern country. RESULTS: There were 156 EPA cases diagnosed over six years, with a mean age of 33 years. Males represented 82% of the cohort. The entire cohort was treated non-operatively except for eight patients who had surgical intervention using open or laparoscopic surgery. The diagnosis was made by a computerized tomographic scan (CT). However, plain X-ray, abdominal ultrasound, and magnetic resonance imaging (MRI) were performed initially in a few selected cases to rule out other conditions. No specific blood test indicated EPA; however, a histopathology examination was diagnostic. No mortality was reported in the study cohort. CONCLUSION: This is the most extensive study analyzing EPA patients from the Middle East. EPA is a rare and mostly self-limiting acute abdominal disorder; however, early ultrasound and CT scan can pick it up quickly after a high index of suspicion.

A method for treatment of deep and superficial enteroatmospheric fistulas in an open abdomen, ChimneyVAC: Ten years experience.

BACKGROUND: Leakage of intestinal fluid is a challenging event when it appears in an open abdomen (OA) and surgical deviation does not seem possible. Intestinal contents in the abdominal cavity maintain inflammation and drainage is there for essential. We have developed a method, ChimneyVAC, to treat both deep and superficial enteroatmospheric fistulas (EAF) AIMS: To describe this innovative surgical technique and our 10-year experience. MATERIAL & METHODS: This single-center observational cohort study included all 16 consecutive patients treated with ChimneyVAC. Seven women and 9 men; median age: 47; (interquartile range [IQR]:39-63) years, 15 with a small bowel fistula and 1 with a large bowel fistula. All except of the colonic fistula were classified as a high output fistula; 14 were deep and 2 superficial. In this technique, a negative-pressure source is applied directly above the fistula opening, in addition to negative pressure wound therapy for the OA. This controls the leakage of intestinal fluid by direct drainage into a vacuum system, thereby avoiding contamination of the abdomen. A controlled enterocutaneous fistula (ECF) then forms as the traction from the ChimneyVAC brings the fistula opening to skin level. RESULTS: In 14 patients, an ECF formed after a median of 42 (IQR:28-55) days and 12 (IQR:7-16) dressing changes. The median length of hospitalization was 103 (IQR:58-143) days. Two patients died of multiorgan failure and 14 initially survived. DISCUSSION: This study showed that 14 out of 16 patients survived the initial treatment for enteric leakage with the ChimneyVAC method. The outcome of ChimneyVAC treatment is a controlled ECF, which was then corrected after a median of six months. However, hospitalization is lengthy, the patients undergo several dressing changes and many needs additional parenteral nutrition until intestinal continuity is reestablished. CONCLUSION: ChimneyVAC is a feasible method for treatment of EAF in an OA, with favorable survival.

The open abdomen in mesenteric ischemia: A tool for patients undergoing revascularization.

BACKGROUND: We examined outcomes in Acute Mesenteric Ischemia (AMI) with the hypothesis that Open Abdomen (OA) is associated with decreased mortality. METHODS: We performed a cohort study reviewing NSQIP emergency laparotomy patients, 2016-2020, with a postoperative diagnosis of mesenteric ischemia. OA was defined using flags for patients without fascial closure. Logistic regression was used with outcomes of 30-day mortality and several secondary outcomes. RESULTS: Out of 5514 cases, 4624 (83.9%) underwent resection and 387 (7.0%) underwent revascularization. The OA rate was 32.6%. 10.8% of patients who were closed required reoperation. After adjustment for demographics, transfer status, comorbidities, preoperative variables including creatinine, white blood cell count, and anemia, as well as operative time, OA was associated with OR 1.58 for mortality (95% CI [1.38, 1.81], p < 0.001). Among revascularizations, there was no such association (p = 0.528). OA was associated with ventilator support >48 h (OR 4.04, 95% CI [3.55, 4.62], and p < 0.001). CONCLUSION: OA in AMI was associated with increased mortality and prolonged ventilation. This is not so in revascularization patients, and 1 in 10 patients who underwent primary closure required reoperation. OA should be considered in specific cases of AMI. LEVEL OF EVIDENCE: Retrospective cohort, Level III.

Quantitative 23Na magnetic resonance imaging in the abdomen at 3 T.

OBJECTIVES: To assess the feasibility of sodium-23 MRI for performing quantitative and non-invasive measurements of total sodium concentration (TSC) and relaxation in a variety of abdominal organs. MATERIALS AND METHODS: Proton and sodium imaging of the abdomen was performed in 19 healthy volunteers using a 3D cones sequence and a sodium-tuned 4-rung transmit/receive body coil on a clinical 3 T system. The effects of B1 non-uniformity on TSC measurements were corrected using the double-angle method. The long-component of 23Na T2* relaxation time was measured using a series of variable echo-times. RESULTS: The mean and standard deviation of TSC and long-component 23Na T2* values were calculated across the healthy volunteer group in the kidneys, cerebrospinal fluid (CSF), liver, gallbladder, spleen, aorta, and inferior vena cava. DISCUSSION: Mean TSC values in the kidneys, liver, and spleen were similar to those reported using 23Na-MRI previously in the literature. Measurements in the CSF and gallbladder were lower, potentially due to the reduced spatial resolution achievable in a clinically acceptable scan time. Mean long-component 23Na T2* values were consistent with previous reports from the kidneys and CSF. Intra-population standard error was larger in smaller, fluid-filled structures due to fluid motion and partial volume effects.