A "global village": promoting research and careers in the pediatric radiology community through diversity.

There is a severe shortage of pediatric radiologists in the USA and across the globe due to multiple factors. These severe shortages, along with increased clinical demand, growing research costs and limited funding sources place pediatric radiologists, particularly those in academic departments, under increasing time pressure, affecting their ability to maintain research productivity. In this paper, we model a new concept that should help boost the research efforts within the pediatric radiology community, while diversifying the academic workforce through the involvement of international medical graduates (IMGs). We describe the mutual advantages this concept could have on academic pediatric radiology departments and IMGs alike, as well as pose some of the unique challenges that could impact this concept and effective strategies to ensure success.

Imaging fibrosis in pediatric kidney transplantation: A pilot study.

BACKGROUND: Noninvasive alternatives to biopsy for assessment of interstitial fibrosis and tubular atrophy (IFTA), the major determinant of kidney transplant failure, remain profoundly limited. Elastography is a noninvasive technique that propagates shear waves across tissues to measure their stiffness. We aimed to test utility of elastography for early detection of IFTA in pediatric kidney allografts. METHODS: We compared ultrasound (USE) and MR elastography (MRE) stiffness measurements, performed on pediatric transplant recipients referred for clinically indicated biopsies, and healthy controls. RESULTS: Ten transplant recipients (median age 16 years) and eight controls (median age 16.5 years) were enrolled. Three transplant recipients had "stable" allografts and seven had Banff Grade 1 IFTA. Median time from transplantation to biopsy was 12 months. Mean estimated glomerular filtration rate was 61.5 mL/min/1.73m2 by creatinine-cystatin-C CKiD equation at time of biopsy. Mean stiffness, calculated through one-way ANOVA, was higher for IFTA allografts (23.4 kPa USE/5.6 kPa MRE) than stable allografts (13.7 kPa USE/4.4 kPa MRE) and controls (9.1 kPa USE/3.6 kPa MRE). Pearson's coefficient between USE and MRE stiffness values was strong (r = .97). AUC for fibrosis prediction in transplanted kidneys was high for both modalities (0.91 USE and 0.89 MRE), although statistically nonsignificant (p > .05). Stiffness cut-off values for USE and MRE were 13.8 kPa and 4.6 kPa, respectively. Both values yielded a sensitivity of 100% but USE specificity (72%) was slightly higher than MRE (67%). CONCLUSION: Elastography shows potential for detection of low-grade IFTA in allografts although a larger sample is imperative for clinical validation.

Magnetic resonance urography: a practical approach to preparation, protocol and interpretation.

Magnetic resonance urography (MRU) is an important MRI application that provides noninvasive comprehensive morphological and functional evaluation of the kidneys and urinary tract. It can be used to assess congenital anomalies of the kidney and urinary tract, which often present as urinary tract dilation. In children, MRU allows for high tissue contrast and high spatial resolution without requiring ionizing radiation. Magnetic resonance urography requires patient preparation in the form of pre-examination intravenous hydration, placement of a urinary catheter, and the administration of diuretics at the time of the exam. The imaging protocol is based on T2-weighted images for anatomical assessment and dynamic post-contrast images for functional evaluation. These images are then used to generate quantitative and graphic results including contrast transit and excretion time as well as to calculate differential renal function. This review focuses on a simple approach to pediatric MRU acquisition and interpretation based on clinical cases and the authors' experience.

Retrograde urethrography in children: a decade of experience at a children's hospital.

BACKGROUND: Retrograde urethrography (RUG) is a radiologic procedure that optimizes imaging evaluation of the urethra, particularly in settings of difficulty with micturition or urethral injury. OBJECTIVE: To review our experience with RUG at a large pediatric radiology practice. MATERIALS AND METHODS: We conducted a retrospective review of medical records and fluoroscopic images of RUGs performed from January 2010 to December 2020. RESULTS: We identified 180 RUG exams (median frequency 17 exams per year), all in male children (median age 13 years). The most common indications were stricture (42%; n=76), postsurgical evaluation (34%; n=62) and trauma (16%; n=29). The most commonly used catheter was Foley (40%; n=72), with a median catheter size of 5 French (Fr) for infants younger than 1 year, 7 Fr for children ages 1-5 years and 8 Fr for children older than 5 years. About a third of the children (57; 32%) had combined voiding cystourethrography (VCUG)-RUG exams. Water-soluble contrast agent, either 17% or 43% Cysto-Conray, was used. Most RUG exams were normal (46%; n=83). The most common urethral pathology was stricture (30%; n=54), commonly involving a bulbar urethra (n=26). Urethral trauma was seen in 11 children (6%), 10 bulbar and 1 membranous. Most children with stricture were surgically treated (n=40; 74%), whereas most children with trauma were conservatively treated (n=8; 73%). The remaining diagnoses included diverticula, polyps, valves, fistulas and duplications, constituting <17% of our sample; most of these were surgically treated. Four exams (2%) were non-diagnostic. RUG showed 89% sensitivity and 97% specificity compared to cystourethroscopy/VCUG findings. Technical difficulties occurred in 14 (8%) children (e.g., pain or inappropriate catheter seal). CONCLUSION: Our experience indicates that when catheterization techniques are properly tailored, RUG provides a useful and successful radiologic method of evaluating the pediatric male urethra.

Comparison of chest radiograph findings in ambulatory and hospitalized children with pulmonary tuberculosis.

BACKGROUND: The diagnosis of childhood tuberculosis (TB) is, in many instances, solely reliant on chest radiographs (CXRs), as they are often the only diagnostic tool available, especially in TB-endemic areas. Accuracy and reliability of CXRs for detecting TB lymphadenopathy may vary between groups depending on severity of presentation and presence of parenchymal disease, which may obscure visualization. OBJECTIVE: To compare CXR findings in ambulatory versus hospitalized children with laboratory confirmed pulmonary TB versus other lower respiratory tract infections (LRTI) and test inter-rater agreement for these findings. MATERIALS AND METHODS: Retrospective review, by two pediatric radiologists, of CXRs performed on children < 12 years old referred for evaluation of LRTI with clinical suspicion of pulmonary TB in inpatient and outpatient settings. Each radiologist commented on imaging findings of parenchymal changes, lymphadenopathy, airway compression and pleural effusion. Frequency of imaging findings was compared between patients based on location and diagnosis and inter-rater agreement was determined. Accuracy of radiographic diagnosis was compared to laboratory testing which served as the gold standard. RESULTS: The number of enrolled patients was 181 (54% males); 69 (38%) were ambulatory and 112 (62%) were hospitalized. Of those enrolled, 87 (48%) were confirmed to have pulmonary TB, while 94 (52%) were other LRTI controls. Lymphadenopathy and airway compression were more common in TB patients than other LRTI controls, regardless of patient location. Parenchymal changes and pleural effusion were more common in hospitalized than ambulatory patients, regardless of patient diagnosis. Agreement for parenchymal changes was higher in the hospitalized group (kappa [κ] = 0.75), while agreement for lymphadenopathy (κ = 0.65) and airway compression (κ = 0.68) was higher in the ambulatory group. The specificity of CXRs for TB diagnosis (> 75%) was higher than the sensitivity (< 50%) for both ambulatory and hospitalized groups. CONCLUSION: Higher frequency of parenchymal changes among hospitalized children may conceal specific imaging findings of TB such as lymphadenopathy, contributing to the poor reliability of CXRs. Despite this, the high specificity of CXRs shown in our results is encouraging for continued use of radiographs for TB diagnosis in both settings.

A roadmap to success: Securing a radiology residency through a research fellowship - Insights from a former international fellow.

Given the increasing competitiveness of matching into radiology residency programs in the U.S., especially for international medical graduates (IMGs), many IMGs opt to join research fellowships to boost their academic productivity and expand their research portfolios. This strategy helps them become as competitive as their national peers. This paper provides insights from the personal experience of a former international radiology research fellow who successfully utilized a fellowship to match into a radiology residency. It outlines a roadmap and strategic steps taken-from finding and preparing for the fellowship to maximizing its benefits by increasing publications and developing professional connections, ultimately securing a radiology residency, and maintaining ongoing collaboration with the research team after departure.

Evaluation of quality of renal tract ultrasound scans and reports performed in children with first urinary tract infection.

PURPOSE: To determine the quality of renal tract ultrasound (US) imaging records performed in children for evaluation of urinary tract infection (UTI) by multiple professionals with different levels of experience in a dedicated academic children's hospital. METHODS: Retrospective analysis of US images and reports for children ≤ 13-years with first presentation of a UTI. 9 Operators (6 consultant radiologists and 3 sonographers) were anonymised and the adequacy of their US images and reports were evaluated for the following categories; Image acquisition, Image labelling, Metric labelling, and Final reporting. The frequency of the reporting quality of the elements assessed was compared between radiologists and sonographers using Chi-square or fisher exact test. RESULTS: Renal tract US studies for 100 children (20 males, 80 females) with first UTI episode were assessed. Mean age was 4.5 ± 3.4 years. 54% of the studies were performed by sonographers and 46% by radiologists. Kidneys and pre-micturition bladder scans were acquired in more than 96% of exams by both sonographers and radiologists. Kidney image and metric labelling was adequate in almost all exams (98-100%) with the exception of plane labelling which was not routinely done by US operators (less than 3%). Sonographers performed consistently better than radiologists in post-micturition bladder scanning, pre- and post-micturition bladder labelling and renal length reporting (p<0.05). Least to be recorded by US operators (both radiologists and sonographers) were doppler scan acquisitions (less than 3%), bladder wall thickness labelling (less than 3%), and renal calculi reporting (less than 1%). CONCLUSION: The inconsistency of the reporting quality between the different elements assessed highlights the difference in US training and experience received by sonographers and radiologists. A pro-forma structured reporting template may ensure US operators provide consistent, thorough and good quality ultrasound images and reports.

Liver and spleen volume and stiffness in patients post-Fontan procedure and patients with ARPKD compared to normal controls.

PURPOSE: Both congestive (patients post-Fontan hepatopathy) and congenital (patients with ARPKD) disease can lead to hepatic fibrosis and portal hypertension with eventual development of splenomegaly. We investigated liver and spleen stiffness as measured by MRE between post-Fontan, ARPKD patients and controls independent of organ volume. METHODS: Our study included 122 subjects (70 Fontan patients, 14 ARPKD patients, and 38 controls). The mean MRE liver and spleen stiffness values of Fontan patients and patients with ARPKD were compared to controls. Similarly, the liver and spleen volumes of the Fontan patients and patients with ARPKD were then compared to the volumes of controls. RESULTS: Post-Fontan and ARPKD patients, mean liver stiffness, mean liver volume as well as mean spleen stiffness and mean spleen volume were higher than mean liver stiffness, mean liver volume, mean spleen stiffness, and mean spleen volume of controls. While liver stiffness correlated to liver volume in controls, we found no correlation between stiffness and volume in either Fontan or ARPKD patients, which indicates MRE's ability to act as an independent biomarker. However, these findings are not true in the spleen, where there is significant association between volume and stiffness in patients with ARPKD, but not in Fontan patients or controls. CONCLUSION: Liver and spleen stiffness and volumes are significantly different among Fontan patients, ARPKD patients, and controls. Our findings suggest that beyond diagnosing fibrosis, MRE cut-off values could be disease-specific since not only the severity but the underlying pathology causing organ congestion or fibrosis influences MRE results.

Added value of gadolinium-based contrast agents for magnetic resonance evaluation of adnexal torsion in girls.

PURPOSE: Ultrasound is the first-line imaging modality to evaluate adnexa in girls with clinical suspicion of torsion. Patients with equivocal ultrasound findings can undergo MRI for better delineation of adnexal pathology. Here, we assess the utility of intravenous contrast in MRI evaluation of adnexal torsion in children. METHODS: Two pediatric radiologists (R1, R2) retrospectively reviewed 198 pelvic MRI exams in 172 girls (median age 15 years). Each MRI was reviewed twice. The first review included pre-contrast images only. A second review, at least 1 month later, included both pre- and post-contrast images. Readers concluded if findings were suspicious for torsion or not. Readers' findings were compared to each other's and to surgical and MRI reports and clinical course. RESULTS: 198 MRI exams yielded 354 evaluable ovaries. Surgical and pathological reports were available for 47 patients. 11 patients had adnexal torsion. Both readers accurately diagnosed acutely torsed ovaries during pre- and post-contrast reviews (n = 4). However, readers disagreed on torsed paraovarian cysts (n = 4) and chronically/intermittently torsed ovaries (n = 3). In 21 non-torsed ovaries that had lesions, one or both readers concluded that there were pre-contrast features of torsion. In this set with ovarian lesions, contrast helped readers to correctly conclude no torsion (R1 = 8, R2 = 6) more commonly than to incorrectly conclude torsion (1 each), improving post-contrast specificity for each reader. CONCLUSIONS: Post-contrast sequences did not provide additional benefit in evaluating acutely torsed ovaries but helped in excluding torsion in patients with adnexal lesions. Therefore, contrast administration should be individualized, potentially reserved only for those with abnormal ultrasound or pre-contrast images.

Frequency of duodenal anatomical variants in neonatal and pediatric upper gastrointestinal tract series (UGI) and the influence of exam quality on diagnostic reporting of these.

AIM: To determine frequency of duodenal anatomical variants on clinically indicated pediatric UGI examinations and determine the influence of these variants and exam quality on the reliability of diagnosis. MATERIALS AND METHODS: Two-pediatric radiologists retrospectively reviewed 100-UGI exams performed on children ≤18-years. Exams were considered diagnostic if the duodenojejunal (DJ) flexure was identified. For diagnostic exams, readers categorized the duodenal location and shape as: normal, normal variant, or abnormal. Exam quality was assessed according to duodenal visualization, number of boluses required, and patient positioning. RESULTS: Reader 1: 90/100 exams diagnostic -77% normal duodenum, 20% normal variant, and 3% abnormal. Reader 2: 97/100 exams diagnostic - 88% normal, 8% normal variant, and 4% abnormal. Original reports: 99/100 exams diagnostic - 92% normal, 3% normal variant, and 5% abnormal. 42% of exams were "high-quality" and 58% were "low-quality". The number of abnormal was the same between readers in "high-quality" studies. In "low-quality" studies reader 1 and the original read diagnosed 1 further case as non-rotation which was diagnosed as a normal variant by reader 2. Two further cases were reported as non-rotation by the original reader. Inter-rater reliability was significantly higher among each pair of raters in "high quality" exams (κ 0.3; p ≤ 0.05) compared to "low quality" exams (k < 0.1 - p > 0.05). CONCLUSION: Duodenal variants were diagnosed in 8-20% of UGI. Compromised exam quality contributes to poor interrater reliability and may result in diagnostic errors of normal variant duodenums, posing a risk for unnecessary intervention and/or delayed treatment.