Machine Learning Detection and Characterization of Splenic Injuries on Abdominal Computed Tomography.

BACKGROUND: Multi-detector contrast-enhanced abdominal computed tomography (CT) allows for the accurate detection and classification of traumatic splenic injuries, leading to improved patient management. Their effective use requires rapid study interpretation, which can be a challenge on busy emergency radiology services. A machine learning system has the potential to automate the process, potentially leading to a faster clinical response. This study aimed to create such a system. METHOD: Using the American Association for the Surgery of Trauma (AAST), spleen injuries were classified into 3 classes: normal, low-grade (AAST grade I-III) injuries, and high-grade (AAST grade IV and V) injuries. Employing a 2-stage machine learning strategy, spleens were initially segmented from input CT images and subsequently underwent classification via a 3D dense convolutional neural network (DenseNet). RESULTS: This single-centre retrospective study involved trauma protocol CT scans performed between January 1, 2005, and July 31, 2021, totaling 608 scans with splenic injuries and 608 without. Five board-certified fellowship-trained abdominal radiologists utilizing the AAST injury scoring scale established ground truth labels. The model achieved AUC values of 0.84, 0.69, and 0.90 for normal, low-grade injuries, and high-grade splenic injuries, respectively. CONCLUSIONS: Our findings demonstrate the feasibility of automating spleen injury detection using our method with potential applications in improving patient care through radiologist worklist prioritization and injury stratification. Future endeavours should concentrate on further enhancing and optimizing our approach and testing its use in a real-world clinical environment.

Interrater Agreement of CT Grading of Blunt Splenic Injuries: Does the AAST Grading Need to Be Reimagined?

Introduction: The Revised Organ Injury Scale (OIS) of the American Association for Surgery of Trauma (AAST) is the most widely accepted classification of splenic trauma. The objective of this study was to evaluate inter-rater agreement for CT grading of blunt splenic injuries. Methods: CT scans in adult patients with splenic injuries at a level 1 trauma centre were independently graded by 5 fellowship trained abdominal radiologists using the AAST OIS for splenic injuries - 2018 revision. The inter-rater agreement for AAST CT injury score, as well as low-grade (IIII) versus high-grade (IV-V) splenic injury was assessed. Disagreement in two key clinical scenarios (no injury versus injury, and high versus low grade) were qualitatively reviewed to identify possible sources of disagreement. Results: A total of 610 examinations were included. The inter-rater absolute agreement was low (Fleiss kappa statistic 0.38, P < 0.001), but improved when comparing agreement between low and high grade injuries (Fleiss kappa statistic of 0.77, P < .001). There were 34 cases (5.6%) of minimum two-rater disagreement about no injury vs injury (AAST grade ≥ I). There were 46 cases (7.5%) of minimum two-rater disagreement of low grade (AAST grade I-III) versus high grade (AAST grade IV-V) injuries. Likely sources of disagreement were interpretation of clefts versus lacerations, peri-splenic fluid versus subcapsular hematoma, application of adding multiple low grade injuries to higher grade injuries, and identification of subtle vascular injuries. Conclusion: There is low absolute agreement in grading of splenic injuries using the existing AAST OIS for splenic injuries.

Pre-operative embolization of a complex systemic to pulmonary vascular malformation.

A 38-year-old male patient presenting with mild exertional dyspnea was noted to have a lingular opacity on chest radiograph. CT of the chest demonstrated an unusual complex inferior lingular vascular malformation with branches arising from the left internal thoracic artery and the left inferior diaphragmatic artery via the celiac artery. There was suspected communication with both pulmonary arterial and venous branches. Following thorough assessment and comprehensive clinical investigation, the patient elected to proceed to definitive surgical management due to potential risk of life-threatening hemoptysis. Interventional radiology performed pre-operative diagnostic angiography and embolization of the systemic feeding arteries. The patient proceeded to have an uncomplicated video-assisted thoracoscopic surgery segmentectomy and was discharged the next day. The patient was asymptomatic at follow-up with complete resolution of the malformation on CT at 6 months. We discuss an uncommon pathology which benefited from multidisciplinary management including successful pre-operative endovascular embolization.

Late Peritoneal Dialysis Exit-Site Leak: A Case Report.

Peritoneal dialysis (PD) pericatheter exit-site leaks most commonly occur early, within 30 days of catheter insertion. Late exit-site leaks are rare. The distinction between early and late exit-site leaks is important because the causes and subsequent management strategies may be different. Early leaks can often be first treated by delaying or holding PD therapy, allowing the prolongation of the healing time because fibrous tissue continues to form around the deep cuff. Late leaks are less likely to heal with cessation of PD alone and often require PD catheter replacement. In this case report, we provide an overview of the diagnosis and management of PD catheter exit-site leaks while highlighting a case of a late presenting exit-site leak resulting from a unique cause of PD catheter trauma.

Infection complications after transrectal ultrasound-guided prostate biopsy: A radiology department's experience and strategy for improvement.

INTRODUCTION: Transrectal ultrasound (TRUS)-guided prostate biopsy is a common procedure performed to diagnose prostate cancer. The risk of infection complications is well-described in the literature, and strategies to avoid such complications continue to evolve over time. We performed a retrospective review of our infection complications and propose a strategy for improvement. METHODS: We reviewed clinical outcomes from patients undergoing TRUS-guided prostate biopsy at our institution from November 2018 to November 2020. We reported the antimicrobial prophylaxis received, whether the biopsy was systematic or targeted, and we examined the rate of clinically significant infection complications and hospitalization. RESULTS: Among 312 men who underwent TRUS-guided prostate biopsy during the study period, seven (2.2%) had an infection. Four patient groups with distinct antimicrobial regimen were identified; the largest of these patient groups received a three-day course of cefixime and a single dose of fosfomycin (59%). The proportion of patients with infection complications across these groups did not demonstrate a statistically significant difference (p=0.803). There was no significant difference in proportion of infection between systematic and targeted biopsy groups (3.0% vs. 0%, p=0.204). The proportion of patients hospitalized was 1.3%, with a mean length of stay of four days. CONCLUSIONS: We report a rate of clinically significant infection following TRUS-guided prostate biopsy of 2.2%. Due to our referral pathway, we have an inconsistent approach to antimicrobial prophylaxis, although there was no statistically significant difference in infection rate between the groups. We propose a standardized approach that may lead to improved patient outcomes.

Appendiceal tumours - A correlation of CT features and histopathological diagnosis.

Appendiceal tumours are uncommon neoplasms of the gastrointestinal tract. An understanding of the imaging appearances facilitates an accurate radiological description, which guides surgical and oncological management. In this study, a retrospective review of the CT imaging and histopathology of all cases of appendiceal tumours discussed at the oncology multidisciplinary meetings in a single centre, over an 8-year period (2012-2019) is performed. The array and incidence of both common and rare pathologies are investigated, and important characteristic imaging findings for radiologists to recognize are highlighted.