A case report of hepatic fetus-in-fetu: Approach to diagnosis.

Multiple theories have been proposed about the pathophysiology of Fetus-in-fetu (FIF). The most widely accepted theory is abnormal embryogenesis in diamniotic monochorionic pregnancies, in which a malformed parasitic fetus is found within the body of a twin host. Hepatic FIF has been reported in almost 1% of FIF cases, with only 2 case reports being published in the literature. This article presents the third case report of intrahepatic FIF. Additionally, we review the role of radiology in diagnosing these cases and guiding their proper management. This case report supports the monozygotic twin theory of FIF and the diagnostic dilemma of FIF vs. teratoma can be solved through collaborative work between radiologists and pathologists.

Properties of ultrasound-rapid MRI clinical diagnostic pathway in suspected pediatric appendicitis.

OBJECTIVE: to determine diagnostic accuracy of an US-MRI clinical diagnostic pathway to detect appendicitis in the emergency department (ED). STUDY DESIGN: prospective cohort study of 624 previously healthy children 4-17 years old undergoing US for suspected appendicitis and clinical re-assessment. Children with non-diagnostic USs and persistent appendicitis concern/conclusive US-reassessment discrepancies underwent ultra-rapid MRI (US-MRI pathway), interpreted as positive, negative or non-diagnostic. Cases with missed appendicitis, negative appendectomies, and CT utilization were considered clinically diagnostically inaccurate. Primary outcome was the proportion of accurate diagnoses of appendicitis/lack thereof by the pathway. RESULTS: 150/624 (24%) children had appendicitis;255 USs (40.9%) were non-diagnostic. Of 139 US-MRI pathway children (after 117 non-diagnostic and 22 conclusive USs), 137 [98.6%; 95% CI 0.96-1.00] had clinically accurate outcomes (1 CT, 1 negative appendectomy): sensitivity 18/18 [100%], specificity 119/121 [98.3%], positive predictive value 18/20 [90.5%], negative predictive value 119/119 [100%]. MRI imaging accuracy was 134/139 (96.4%); 3 MRIs were non-diagnostic (no appendicitis). In the overall algorithm, 616/624 [98.7% (0.97-0.99)] patients had accurate outcomes: 147/150 (98.0%) appendicitis cases had confirmatory surgeries (3 CTs) and 469/474 (98.9%) appendicitis-negative children had no surgery/CT. CONCLUSION: this study demonstrated high clinical accuracy of the US-rapid-MRI pathway in suspected pediatric appendicitis after non-diagnostic US.

Two-dimensional ultrasound shear wave elastography for identifying and staging liver fibrosis in pediatric patients with known or suspected liver disease: a clinical effectiveness study.

BACKGROUND: Ultrasound shear wave elastography (SWE) measures liver stiffness noninvasively, but few studies have defined cutoff values for detecting liver fibrosis in pediatric patients using 2-D ultrasound SWE. OBJECTIVE: To evaluate the diagnostic performance of 2-D ultrasound SWE and define cutoff values for liver fibrosis in pediatric patients, using Canon (Toshiba) Aplio ultrasound systems. MATERIALS AND METHODS: This was an institutional review board-approved retrospective study of patients (≤18 years old) who had undergone both liver 2-D ultrasound SWE and percutaneous liver biopsy within 6 months. Liver biopsies were staged using the METAVIR (fibrosis) scoring system. Continuous data were compared using the Mann-Whitney U test. Receiver operating characteristic (ROC) curve analysis was used to evaluate diagnostic performance. RESULTS: Forty-six patients, with a median age of 11.5 years (interquartile range: 8.0-14.3 years), were included. Twenty-three patients were male (50%). Twenty-seven patients had a METAVIR fibrosis score of F0-1, and 19 patients had a score of F2-4. For differentiating METAVIR F0-1 from F2--4, the area under the ROC (AuROC) was 0.75 (95% confidence interval [CI]: 0.60-0.90). A cutoff of >1.89 m/s yielded sensitivity of 73.7% (95% CI: 51.2-88.2) and specificity of 77.8% (95% CI: 59.2-89.4). For the subset of patients without histological hepatic steatosis (n=35), the AuROC was 0.86 (95% CI: 0.71-1.0). The same cutoff of >1.89 m/s yielded a sensitivity of 80.0% (95% CI: 54.8-93.0) and specificity of 95.0% (95% CI 76.4-99.7). CONCLUSION: Two-dimensional ultrasound SWE distinguishes patients with no/mild fibrosis from those with moderate/severe fibrosis with good sensitivity and specificity. Diagnostic performance is comparable to that published for magnetic resonance elastography and is likely adversely impacted by steatosis.

A case of urinary bladder agenesis and bilateral ectopic ureters: a case report.

BACKGROUND: Urinary bladder agenesis is a very rare congenital anomaly with very few cases reported in the literature. CASE PRESENTATION: We report a one-month-old baby presenting with ambiguous genitalia and recurrent urinary tract infections. Her clinical course was complicated by renal impairment. Magnetic resonant imaging (MRI) revealed a diagnosis of bladder agenesis with bilateral ectopic insertion of the ureters into the vagina, associated with several other anomalies. The patient underwent bilateral high anterior ureterostomies in an hospital abroad at 5.5 months of age. She then developed ureteral necrosis that had to be corrected with left pyeloplasty and by placing a left nephrostomy tube for drainage. Eventually, the patient's renal function declined, and she developed chronic kidney disease (CKD).The case with its imaging findings and pathogenesis as well as a review of the literature are presented. CONCLUSIONS: Urinary bladder agenesis is a rare congenital condition that can be associated with multiple anomalies. Early diagnosis and therapeutic intervention can prevent progression to chronic kidney disease.

Impact of high-fidelity transvaginal ultrasound simulation for radiology on residents' performance and satisfaction.

RATIONALE AND OBJECTIVES: Because of the intimate and uncomfortable nature of transvaginal ultrasound, training residents to perform this type of examination is a difficult task. As a consequence, residents may receive inadequate training that leads to a lack of the skills and confidence needed to perform this examination. The aim of the study was to assess the effectiveness of using simulation sessions to teach residents how to perform transvaginal ultrasound, enabling them to diagnose obstetric and gynecologic emergencies and helping them survive on-calls alone while keeping their patients safe. MATERIALS AND METHODS: We used an experimental study design to compare the confidence levels of 20 senior residents who received clinical training only to those of 25 junior residents who were enrolled in a simulation-based teaching session. We also compared the junior residents' levels of performance and confidence using transvaginal ultrasound before and after the sessions. RESULTS: The performance of transvaginal ultrasound by the junior residents and their confidence levels significantly improved after they attended the simulation sessions. They had higher levels of confidence than the senior residents who did not attend the session. It was also observed that the number of nondiagnostic transvaginal ultrasounds performed by the on-call resident that needed to be repeated the next day had significantly dropped. CONCLUSIONS: Simulation-based teaching sessions are an effective method of education, which improve trainees' skills and confidence levels and improve patient safety.