Utility of Doppler Echocardiography to Estimate the Severity of Pulmonary Valve Regurgitation Fraction in Patients with Repaired Tetralogy of Fallot.

BACKGROUND: In patients with repaired Tetralogy of Fallot (rTOF), pulmonary regurgitation (PR) leads to significant morbidity. Cardiac magnetic resonance imaging (CMR) is the gold standard to assess severity of PR in rTOF patients. We compared Doppler echocardiography derived indices of PR with CMR to find the best predictive parameter for hemodynamically significant (hs) PR. METHODS: This is a retrospective analysis of echocardiogram and CMR measurements. Doppler indices obtained included: PR deceleration slope, pressure half time (PHT) and PR index. Receiver operating characteristic curve analysis was used to optimize the sensitivity and specificity of selected variables in predicting hsPR. Inter-observer variability of the Doppler parameters was assessed in a random sample of 25 Doppler spectral recordings. RESULTS: Our cohort (n = 96) comprised of 52 (54.2%) males. The mean (SD) age at CMR was 22.9 (10.3) years. 83.4% patients underwent complete repair with transannular patch. 78 (81%) patients had hsPR as defined by CMR PR > 20%. Doppler parameters with the values of; PR index of < 0.86, PR deceleration slope of > 375 cm/s2 and a PHT < 130 ms, demonstrated high sensitivity (93%) and high negative predictive values (98-99%). All the Doppler indices demonstrated minimal inter-observer variability (PHT = 0.9, 95% CI 0.69-0.97; PRi = 0.95, 95%CI 0.83-0.98). CONCLUSION: Our data, with its high negative predictive values, show that Doppler derived echocardiography indices have an ability to rule out hsPR, as measured by CMR. PHT, PR index and deceleration slope correlate with hsPR and can be used as screening tools for further testing.

The RIVUR voiding cystourethrogram pilot study: experience with radiologic reading concordance.

PURPOSE: Two reference radiologists independently review voiding cystourethrograms for the National Institutes of Health sponsored RIVUR (Randomized Intervention for Children with Vesicoureteral Reflux) trial for children with vesicoureteral reflux. A pilot study was required from all clinical centers before enrolling patients. MATERIALS AND METHODS: Digital images were reviewed. Responses were compared and discrepancies adjudicated by teleconference to a final assessment. RESULTS: A total of 75 studies from 19 sites were reviewed. Discrepancies in vesicoureteral reflux grade level were noted on the left and right side in 11 (15%, kappa 0.85) and 12 (16%, kappa 0.83) ureters, respectively. Other areas of disagreement were the presence of paraureteral diverticulum (left 11%, kappa 0.31; right 9%, kappa 0.34), urethral anatomy (15%, kappa 0.33), whether the child voided (8%, kappa 0.21), the presence of ureteral duplication (left 7%, kappa 0.64; right 3%, kappa 0.78) and the presence of bladder trabeculation (5%, kappa 0.32). Of 83 ureters in which reflux was seen there was grade disagreement about 23 (28%). Of 61 ureters initially assessed as grade II or III reflux by both readers, there was disagreement on 9 (15%). Of these 9 discrepancies 7 (78%) were adjudicated to the higher grade (grade III). CONCLUSIONS: Discrepancies in the assessment of intermediate grade vesicoureteral reflux were noteworthy. Recommendations for patients with grade II or III reflux advanced by studies which rely on a single reading, which categorize only grade III or higher reflux as significant, may not be valid.

Volume US of the urinary tract in pediatric patients-a pilot study.

Three-dimensional ultrasonography (3DUS) adds functionality to two-dimensional ultrasonography (2DUS) by allowing examiners to explore volume datasets using multiplanar or rendering methods already familiar to radiologists. In this pilot study, 30 patients referred for ultrasound examination of the urinary tract were examined by 3DUS. Three abnormalities initially not detected by 2DUS were seen: bilateral bladder diverticulae, urachal remnant and bilateral accessory renal arteries. Rendered images of the bladder trigone were feasible in the majority of patients. Potential applications of this technology in pediatric uroradiology and technical pitfalls are illustrated.

Reliability of grading of vesicoureteral reflux and other findings on voiding cystourethrography.

INTRODUCTION: Voiding cystourethrography (VCUG) is the modality of choice to diagnose vesicoureteral reflux (VUR). Although grading of VUR is essential for prognosis and clinical decision-making, the inter-observer reliability for grading has been shown to vary substantially. The Randomized Intervention for Children with VesicoUreteral Reflux (RIVUR) trial provides a large cohort of children with VUR to better understand the reliability of VCUG findings. OBJECTIVE: To determine the inter-observer consistency of the grade of VUR and other VCUG findings in a large cohort of children with VUR. STUDY DESIGN: The RIVUR trial is a randomized controlled trial of antimicrobial prophylaxis in children with VUR diagnosed after UTI. Each enrollment VCUG was read by a local clinical (i.e. non-reference) radiologist, and independently by two blinded RIVUR reference radiologists. Reference radiologists' disagreements were adjudicated for trial purposes. The grade of VUR and other VCUG findings were extracted from the local clinical radiologist's report. The unit of analysis included individual ureters and individual participants. We compared the three interpretations for grading of VUR and other VCUG findings to determine the inter-observer reliability. RESULTS: Six-hundred and two non-reference radiology reports from 90 institutions were reviewed and yielded the grade of VUR for 560 left and 524 right ureters. All three radiologists agreed on VUR grade in only 59% of ureters; two of three agreed on 39% of ureters; and all three disagreed on 2% of ureters (Table). Agreement was better (≥92%) for other VCUG findings (e.g. bladder shape "normal"). The non-reference radiologists' grade of VUR differed from the reference radiologists' adjudicated grade by exactly one grade level in 19% of ureters, and by two or more grade levels in 2.2% of ureters. When the participant was the unit of analysis, all three radiologists agreed on the grade of VUR in both ureters in just 43% of cases. DISCUSSION: Our study shows considerable and clinically relevant variability in grading VUR by VCUG. This variability was consistent when comparing non-reference to the adjudicated reference radiologists' assessment and the reference radiologists to each other. This study was limited to children with a history of UTI and grade I-IV VUR and may not be generalizable to all children who have a VCUG. CONCLUSION: The considerable inter-observer variability in VUR grading has both research and clinical implications, as study design, risk stratification, and clinical decision-making rely heavily on grades of VUR.

Variation in the level of detail in pediatric voiding cystourethrogram reports.

INTRODUCTION: Voiding cystourethrogram (VCUG) provides a wealth of data on urinary tract function and anatomy, but few standards exist for reporting VCUG findings. OBJECTIVE: We aimed to assess variability in VCUG reports and to test our hypothesis that VCUG reports from pediatric facilities and pediatric radiologists are more complete than those performed at other facilities or by non-pediatric radiologists. STUDY DESIGN: We analyzed original VCUG reports from children enrolled in the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) trial. A 23-item checklist was created and used to evaluate reporting of technical (e.g. catheter size), anatomic (e.g. vesicoureteral reflux (VUR) presence and grade, bladder shape), and functional information (e.g. bladder emptying). Radiologists were classified as pediatric or non-pediatric radiologists. Facilities were categorized as to whether they were a free-standing pediatric hospital (FSPH), a pediatric "hospital within a hospital" (PHWH), a non-pediatric hospital (NPH), or an outpatient radiology facility (ORF). Multivariate linear regression was used to analyze factors associated with the completeness of the VCUG reports (percent of items reported from the 23-item checklist). RESULTS: Six-hundred and two VCUGs were performed at 90 institutions. Of those, 76% were read by a pediatric radiologist, and 49% were performed at a FSPH (Table). On average, less than half of the 23 items in our standardized assessment tool were included in VCUG reports (mean 48%, SD 12). The completeness of reports varied by facility type: 51% complete at FSPH (SD 11), 50% at PHWH (SD 10), 36% at NPH (SD 11), and 43% at ORF (SD 8) (p < 0.0001). In multivariate analysis, VCUG reports generated at NPH or ORF had 8% fewer items included (95% CI 3.0-12.8, p < 0.01), and those generated at PHWH did not differ from those generated at FSPH. Reports read by a non-pediatric radiologist had 6% fewer items included (95% CI 3-9.7; p < 0.01) compared with those read by a pediatric radiologist. DISCUSSION: There is substantial underreporting of findings in VCUG reports when assessing a widely represented sample of routine, community-generated reports using an idealized standard. Although VUR was often reported, other crucial anatomic and functional findings of the VCUG were consistently underreported across all facility types. CONCLUSION: Although pediatric radiologist and pediatric hospitals generated more complete VCUG reports compared with those having non-pediatric origins, the differences are small when considering the substantial underreporting of VCUG findings in general. This underscores the opportunities for improvement in reporting of VCUG findings.

MRI detection of atrophic kidney in a hypertensive child with a single kidney.

The role of magnetic resonance imaging (MRI) in the work-up of secondary causes of pediatric hypertension is typically restricted to that of renovascular causes where main renal artery stenosis is suspected. We report a case of a 10-year-old female child with hypertension, who was thought to have unilateral renal agenesis, because only a solitary left kidney could be visualized on both ultrasound and renal scintigraphy. Our patient underwent magnetic resonance imaging because of suspected renal artery stenosis in her solitary left kidney. At MRI she was found to have a normal left kidney. However, a very tiny, atrophic right kidney was also visualized. A laparoscopic right nephrectomy was performed, which resulted in complete resolution of her hypertension. This case illustrates a possible additional role for MRI in a very small subset of pediatric hypertensive patients: those with a single kidney on ultrasound.

Definitive diagnosis in children with congenital hypothyroidism.

OBJECTIVES: To investigate the definitive diagnosis and underlying causes of congenital hypothyroidism (CH) in eligible children through the use of a standardized protocol. STUDY DESIGN: Children > or =3 years of age with CH without an identified permanent cause underwent a diagnostic algorithm. Eligible subjects had an anatomically normal thyroid or had not undergone imaging studies. After thyroxine was discontinued for 4 weeks, thyroid function tests and a thyroid ultrasound were obtained. An abnormal ultrasound was followed by a (99m)Tc thyroid scan. A perchlorate washout test was performed in subjects with a normal ultrasound but abnormal thyroid function tests. Children with normal results were followed for 1 year. RESULTS: Of 33 children, 17 were boys. Nine (27%) had an absent or ectopic thyroid, 12 (36%) had dyshormonogenesis, and 12 (36%) had transient CH. Average thyroxine dose before medication discontinuation was 2.9 +/- 0.83 microg/kg in permanent cases versus 2.0 +/- 0.53 microg/kg in transient (P <.002). No complications from discontinuation of thyroxine occurred. CONCLUSIONS: A significant percentage of children with CH have a transient requirement for thyroid hormone. A standardized protocol with thyroid ultrasonography is a safe and sensitive approach to a trial off of thyroxine in select patients.