Factors Affecting Emergency Department Computed Tomography Use in Children.

BACKGROUND: Variability in computed tomography (CT) use during pediatric emergency department (ED) visits has been reported. Our objective was to identify patient and hospital characteristics associated with CT use during pediatric ED visits. METHODS: Patients <18 y treated and released from EDs in the 2006-2012 Nationwide Emergency Department Sample were included. Associations were evaluated between pediatric CT scan rate and patient/hospital factors using logistic mixed effects models. Independent predictors of being a high outlier (having a pediatric CT scan rate in the top 10%) were also evaluated using logistic regression models. RESULTS: There were 1543 EDs and 20,703,273 visits included. CT scans were prescribed in 4.7% of pediatric ED visits; the highest 10% of EDs prescribed CT scans in >7.63% of all pediatric visits. In multivariable analysis, older age, male gender, private insurance, higher zip code level median income, and higher injury severity were all associated with an increased probability of receiving a CT scan (all P < 0.001). The chance of receiving a CT scan also varied by diagnosis and was independently associated with geographic location and annual pediatric ED volume. Rates of CT use increased with increasing pediatric volume up to approximately 5400 annual pediatric visits, and then decreased with volume >5400 annual visits. CONCLUSIONS: Several patient-level and ED-level characteristics, including annual pediatric volume, are associated with the probability of a child having a CT scan during an ED visit. Future work should focus on determining drivers behind these associations to develop intervention strategies to decrease pediatric CT use.

Disparities in Radiation Burden from Trauma Evaluation at Pediatric Versus Nonpediatric Institutions.

BACKGROUND: Computed tomography (CT) imaging protocols and prescribing practices vary across institutions. Pediatric trauma patients imaged at a pediatric trauma center (PTC) may receive less radiation than patients imaged at non-PTCs before transfer. Our objective was to determine differences in radiation exposure from imaging performed at a PTC versus non-PTCs. METHODS: This retrospective analysis included patients <18 y old who underwent CT imaging from January 2013 to August 2015 during a trauma-related encounter. Radiation doses from CT scans were estimated and compared between scans performed at our PTC and non-PTCs before patient transfer using propensity score-weighted median regression. RESULTS: Of 3530 CT scans, 3021 were performed at our PTC and 509 at non-PTCs. Patients imaged at non-PTCs were older and had higher injury severity (all P < 0.05). Patients imaged at non-PTCs more frequently had neck CT (29.0% versus 7.3%) and chest CT (8.3% versus 2.7%), less frequently had abdomen/pelvis CT (19.5% versus 27.9%, all P < 0.01), and had similar rates of head CT (83.9% versus 80.9%, P = 0.18). After propensity weighting, CT scanning was more frequent at non-PTCs and patients received higher cumulative radiation exposure overall (median effective dose 2.36 versus 1.57 mSv, P < 0.001) and for each body region imaged (17% more for head, 191% for neck, 81% for chest, and 33% for abdomen/pelvis). CONCLUSIONS: Pediatric trauma patients imaged at a PTC receive lower radiation burden from CT imaging than patients initially imaged at adult institutions. Broader adoption of pediatric dosing protocols or deferring noncritical CT scans until transfer may mitigate these disparities.

Sclerotherapy for splenic cysts in children.

BACKGROUND: Sclerotherapy has been described as a treatment option for nonparasitic pediatric splenic cysts; however, there are limited data on its long-term effectiveness. METHODS: We performed a retrospective review and prospective follow-up imaging study of children treated for nonparasitic splenic cysts at our institution during 2006-2015. Included patients had International Classification of Disease, Ninth Revision, Clinical Modification diagnosis code 289.59 or 759.0 and underwent either sclerotherapy or a partial splenic operation (partial splenectomy, cyst excision, or marsupialization). Charts were reviewed for demographics, imaging, treatments, and complications. Identified patients were contacted and asked to return for splenic ultrasonography. RESULTS: Six surgical patients and 19 sclerotherapy patients were identified. Sclerotherapy patients underwent a median of four treatments with a decrease in the size of the cyst or complete ablation in 89.5% (17/19). Of the two patients who underwent unsuccessful sclerotherapy, one patient had sclerotherapy with sotradecol and ethanol for eight treatments, developed infection, and underwent total splenectomy. The other patient did not improve with sclerotherapy and underwent partial splenectomy. Nine patients (eight patients treated with sclerotherapy and one patient treated with partial splenectomy) were successfully contacted and underwent follow-up imaging at a median follow-up of 2.4 y since last treatment. Of the eight patients treated with sclerotherapy, four patients remained cyst-free, three had small residual asymptomatic cysts stable in size, and one developed a recurrent small asymptomatic cyst; the patient treated with surgery had no recurrence. CONCLUSIONS: Sclerotherapy appears to be an effective and durable alternative treatment for children with splenic cysts.

How to identify high radiation burden from computed tomography: an example in obese children.

BACKGROUND: Radiation burden from the use of computed tomography (CT) imaging may not be evenly distributed. We tested whether overweight and obese children receive higher radiation burden from CT imaging. METHODS: An automated software tool (DoseWizard) assessed patient-level radiation dose from CT and merged results with clinical data from the electronic health record. CT scans of the head, chest, and abdomen/pelvis (A/P) performed at our institution from January 2013 to August 2015 on patients aged <16 y were processed using this software. Patients were categorized as overweight/obese if they had a body mass index (BMI) greater than the 85th percentile for age. Radiation exposures were compared between groups. Higher dose CT scans were identified as having a radiation dose in the top decile. Multivariate analysis identified factors associated with high-dose CT scans. RESULTS: About 7212 CT scans were included. Overweight/obese patients received similar radiation dose for head CT as compared with normal weight patients (1.51 versus 1.49 mSv, P = 0.04) but higher radiation dose for chest (1.14 versus 0.81 mSv, P < 0.001) and A/P (1.97 versus 1.43 mSv, P < 0.001). In multivariable regression models, being overweight/obese increased the odds of a higher dose chest CT (odds ratio 2.24, P < 0.001) and A/P CT (odds ratio 7.24, P < 0.001). CONCLUSIONS: Overweight and obese children receive higher radiation burden from CT imaging and are one group that deserves consideration of dose monitoring. This software tool can be used to measure changes in radiation exposure and run clinical decision support in future studies targeting high radiation exposure to children.

Factors affecting pediatric patient transfer in testicular torsion.

BACKGROUND: Testicular torsion is a surgical emergency, and interhospital transfer could delay care and increase the risk of orchiectomy. This study identifies factors associated with transfer for pediatric testicular torsion. METHODS: This retrospective cross-sectional study examined emergency department (ED) visits for testicular torsion by men aged 1-21 y in National Emergency Department Sample from 2006 to 2012. Freestanding children's hospitals were excluded. Analyses were weighted to produce nationally representative estimates. Patient- and institutional-level predictors of transfer were evaluated using Rao-Scott chi-square tests and multivariable logistic regression. RESULTS: There were 11,435 ED visits for testicular torsion resulting in admission or transfer. In multivariable regression, the probability of transfer decreased with increasing age but remained higher for patients aged 15-17 y than for those aged 18-21 y (odds ratio [OR] = 1.51, P < 0.001) and was lower for patients living in zip codes in the highest income quartile (OR = 0.69 versus lowest, P = 0.003) or with listed comorbidities (OR = 0.55, P < 0.001). Transfer was less likely in the Northeast (OR = 0.28 versus Midwest, P < 0.001), at urban hospitals (OR = 0.31, P < 0.001), teaching institutions (OR = 0.55, P < 0.001), and level I or II trauma centers (OR = 0.31, P < 0.001). Transfer was less common with increasing annual pediatric ED volume (OR = 0.95 per 1000 patients, P < 0.001). Transfer rates increased significantly over the study period (23.6%-38.8%, P < 0.001). CONCLUSIONS: Older adolescents with testicular torsion are more likely to be transferred than young adults. Interhospital transfers in these patients may represent a potential target for improving care. Future work should focus on evaluating the effect of transfer on the risk for undergoing orchiectomy.

Low vertebral ano-rectal cardiac tracheo-esophageal renal limb screening rates in children with anorectal malformations.

BACKGROUND: The aim of this study was to establish the rate of screening for associated cardiac, vertebral, spinal cord, urologic, and limb anomalies vertebral ano-rectal cardiac tracheo-esophageal renal limb (VACTERL) in children with anorectal malformation (ARM). METHODS: We performed a retrospective cohort study using the Medicaid Analytic eXtract database which contains enrollment and utilization claims and demographic information from all Medicaid enrollees. Patients born between January 2005 and December 2008 with International Classification of Diseases, Ninth Revision codes for a diagnosis of ARM within 30 days of life, an ARM procedure code during the first year of life, and a minimum of 12 months of continuous enrollment were included. VACTERL screening was determined using International Classification of Diseases, Ninth Revision and Current Procedural Terminology codes for diagnostic tests used to detect these anomalies. RESULTS: A total of 406 patients were identified (231 males). Evaluation of the spinal vertebrae was performed in 94% of patients (381 of 406). Spinal cord evaluation was performed in 57% (231 of 406): 52% (121 of 231) received spinal ultrasound (US), 24% (56 of 231) received spinal magnetic resonance imaging, and 23% (54 of 231) received both. Sacral radiographs were performed in 8% (32 of 406) and 77% (313 of 406) underwent an echocardiogram. Genitourinary evaluation was performed in 84% (341 of 406): 67% (229 of 341) received renal US, 8% (27 of 341) received abdominal US, and 25% (85 of 341) received both. Limb evaluation was recorded in 19% (76 of 406). Multiple screening including an echocardiogram, spinal radiograph, spinal cord evaluation, and renal evaluation was performed in 45% (181 of 406); 2% (7 of 406) did not receive any screening tests. CONCLUSIONS: Low VACTERL screening in children with ARM suggests that associated anomalies may be undiagnosed which may lead to increased long-term morbidity.

Current surgical management of intestinal rotational abnormalities.

PURPOSE OF REVIEW: At present, there is a debate as to the management of malrotation in pediatric patients. This review highlights recent literature including the role of laparoscopy, and the management of asymptomatic patients with and without congenital cardiac disease. RECENT FINDINGS: Symptomatic patients are still recommended to undergo open Ladd's procedure. Laparoscopic Ladd's procedure in asymptomatic patients confers a shorter time to tolerating feeds, shorter length of stay, and a decreased rate of bowel obstruction and other complications. It may, however, carry a higher risk of postoperative volvulus. Diagnostic laparoscopy is recommended in asymptomatic patients in whom the diagnosis is uncertain on upper gastrointestinal imaging. Asymptomatic patients with congenital heart disease may be managed with initial observation or operation, based upon individualized risk benefit assessment. If an elective Ladd's procedure is performed, it should take place after palliative cardiac operations have resulted in stable cardiac function. Screening upper gastrointestinal studies in heterotaxy patients may be unnecessary as the reported rates of volvulus in recent studies are low. SUMMARY: Laparoscopic Ladd's procedure may be an acceptable alternative to an open procedure for asymptomatic patients. Observation of asymptomatic patients with congenital cardiac disease is a reasonable alternative in selected patients.

Ultrasound Elastography as a Non-Invasive Method to Monitor Liver Disease in Children with Short Bowel Syndrome: Updated Results.

PURPOSE: The purpose of the study was to determine the accuracy of acoustic radiation force impulse (ARFI) ultrasound elastography in assessing the degree of liver disease in children with short bowel syndrome (SBS). METHODS: A prospective observational cohort study of patients with SBS who underwent a liver biopsy and ARFI elastography was performed. Mean shear wave speed (SWS) and stage of fibrosis was evaluated using t-tests. Receiver operating characteristic curves (ROC) were generated and the area under the curves (AUC) estimated in order to assess the accuracy of SWS measurements to discriminate between stages of fibrosis. RESULTS: Thirty-seven paired elastography and biopsy samples from 31 patients were included. The median age was 0.6 years, and 61% were male. There was a significant positive correlation between stage of fibrosis and mean SWS (ß=0.16 m/s increase per stage, p=<0.001). ROC analysis revealed that mean SWS had good accuracy for discriminating between mild liver fibrosis (F0-F1) and moderate to severe fibrosis (F2-F4) (AUC=0.80, 95% CI 0.65-0.95). In addition, ROC analysis demonstrated that mean SWS can also accurately discriminate between mild to moderate fibrosis (F0-F2) and more severe fibrosis (F3-F4) (AUC=0.84, 95% CI 0.71-0.96). CONCLUSION: ARFI elastography is an accurate, non-invasive method to monitor liver disease in children with SBS. TYPE OF STUDY: Retrospective Cohort Study LEVEL OF EVIDENCE: II.

Can fecal continence be predicted in patients born with anorectal malformations?

PURPOSE: The purpose of this study was to identify factors associated with attaining fecal continence in children with anorectal malformations (ARM). METHODS: We performed a multi-institutional cohort study of children born with ARM in 2007-2011 who had spinal and sacral imaging. Questions from the Baylor Social Continence Scale were used to assess fecal continence at the age of ≥4 years. Factors present at birth that predicted continence were identified using multivariable logistic regression. RESULTS: Among 144 ARM patients with a median age of 7 years (IQR 6-8), 58 (40%) were continent. The rate of fecal continence varied by ARM subtype (p = 0.002) with the highest rate of continence in patients with perineal fistula (60%). Spinal anomalies and the lateral sacral ratio were not associated with continence. On multivariable analysis, patients with less severe ARM subtypes (perineal fistula, recto-bulbar fistula, recto-vestibular fistula, no fistula, rectal stenosis) were more likely to be continent (OR = 7.4, p = 0.001). CONCLUSION: Type of ARM was the only factor that predicted fecal continence in children with ARM. The high degree of incontinence, even in the least severe subtypes, highlights that predicting fecal continence is difficult at birth and supports the need for long-term follow-up and bowel management programs for children with ARM. TYPE OF STUDY: Prospective Cohort Study. LEVEL OF EVIDENCE: II.

Hybrid computational phantoms of the 15-year male and female adolescent: applications to CT organ dosimetry for patients of variable morphometry.

Currently, two classes of the computational phantoms have been developed for dosimetry calculation: (1) stylized (or mathematical) and (2) voxel (or tomographic) phantoms describing human anatomy through mathematical surface equations and three-dimensional labeled voxel matrices, respectively. Mathematical surface equations in stylized phantoms provide flexibility in phantom design and alteration, but the resulting anatomical description is, in many cases, not very realistic. Voxel phantoms display far better anatomical realism, but they are limited in terms of their ability to alter organ shape, position, and depth, as well as body posture. A new class of computational phantoms--called hybrid phantoms-takes advantage of the best features of stylized and voxel phantoms-flexibility and anatomical realism, respectively. In the current study, hybrid computational phantoms representing reference 15-year male and female body anatomy and anthropometry are presented. For the male phantom, organ contours were extracted from the University of Florida (UF) 14-year series B male voxel phantom, while for the female phantom, original computed tomography (CT) data from two 14-year female patients were used. Polygon mesh models for the major organs and tissues were reconstructed for nonuniform rational B-spline (NURBS) surface modeling. The resulting NURBS/polygon mesh models representing body contour and internal anatomy were matched to anthropometric data and reference organ mass data provided by the Centers for Disease Control and Prevention (CDC) and the International Commission on Radiation Protection (ICRP), respectively. Finally, two hybrid 15-year male and female phantoms were completed where a total of eight anthropometric data categories were matched to standard values within 4% and organ masses matched to ICRP data within 1% with the exception of total skin. To highlight the flexibility of the hybrid phantoms, 10th and 90th weight percentile 15-year male and female phantoms were further developed from the 50th percentile phantoms through adjustments in the body contour to match the total body masses given in CDC pediatric growth curves. The resulting six NURBS phantoms, male and female phantoms representing their 10th, 50th, and 90th weight percentiles, were used to investigate the influence of body fat distributions on internal organ doses following CT imaging. The phantoms were exposed to multislice chest and abdomen helical CT scans, and in-field organ absorbed doses were calculated. The results demonstrated that the use of traditional stylized phantoms yielded organ dose estimates that deviate from those given by the UF reference hybrid phantoms by up to a factor of 2. The study also showed that use of reference, or 50th percentile, phantoms to assess organ doses in underweight 15-year-old children would not lead to significant organ dose errors (typically less than 10%). However, more significant errors were noted (up to approximately 30%) when reference phantoms are used to represent overweight children in CT imaging dosimetry. These errors are expected to only further increase as one considers CT organ doses in overweight and obese individuals of the adult patient population, thus emphasizing the advantages of patient-sculptable phantom technology.

Screening practices and associated anomalies in infants with anorectal malformations: Results from the Midwest Pediatric Surgery Consortium.

BACKGROUND: This study evaluates screening practices and the incidence of associated anomalies in infants with anorectal malformations (ARM). METHODS: We performed a multi-institutional retrospective cohort study of children born between 2007 and 2011 who underwent surgery for ARM at 10 children's hospitals. ARM type was classified based on the location of the distal rectum, and all screening studies were reviewed. RESULTS: Among 506 patients, the most common ARM subtypes were perineal fistula (40.7%), no fistula (11.5%), and vestibular fistula (10.1%). At least 1 screening test was performed in 96.6% of patients, and 11.3% of patients underwent all. The proportion of patients with ≥1 abnormal finding on any screening test varied by type of ARM (p<0.001). Screening rates varied from 15.2% for limb anomalies to 89.7% for renal anomalies. The most commonly identified anomalies by screening category were: spinal: tethered cord (20.6%); vertebral: sacral dysplasia/hemisacrum (17.8%); cardiac: patent foramen ovale (58.0%); renal: hydronephrosis (22.7%); limb: absent radius (7.9%). CONCLUSION: Screening practices and the incidence of associated anomalies varied by type of ARM. The rate of identifying at least one associated anomaly was high across all ARM subtypes. Screening for associated anomalies should be considered standard of care for all ARM patients. TYPE OF STUDY: Multi-institutional retrospective cohort study. LEVEL OF EVIDENCE: III.

Hybrid computational phantoms of the male and female newborn patient: NURBS-based whole-body models.

Anthropomorphic computational phantoms are computer models of the human body for use in the evaluation of dose distributions resulting from either internal or external radiation sources. Currently, two classes of computational phantoms have been developed and widely utilized for organ dose assessment: (1) stylized phantoms and (2) voxel phantoms which describe the human anatomy via mathematical surface equations or 3D voxel matrices, respectively. Although stylized phantoms based on mathematical equations can be very flexible in regard to making changes in organ position and geometrical shape, they are limited in their ability to fully capture the anatomic complexities of human internal anatomy. In turn, voxel phantoms have been developed through image-based segmentation and correspondingly provide much better anatomical realism in comparison to simpler stylized phantoms. However, they themselves are limited in defining organs presented in low contrast within either magnetic resonance or computed tomography images-the two major sources in voxel phantom construction. By definition, voxel phantoms are typically constructed via segmentation of transaxial images, and thus while fine anatomic features are seen in this viewing plane, slice-to-slice discontinuities become apparent in viewing the anatomy of voxel phantoms in the sagittal or coronal planes. This study introduces the concept of a hybrid computational newborn phantom that takes full advantage of the best features of both its stylized and voxel counterparts: flexibility in phantom alterations and anatomic realism. Non-uniform rational B-spline (NURBS) surfaces, a mathematical modeling tool traditionally applied to graphical animation studies, was adopted to replace the limited mathematical surface equations of stylized phantoms. A previously developed whole-body voxel phantom of the newborn female was utilized as a realistic anatomical framework for hybrid phantom construction. The construction of a hybrid phantom is performed in three steps: polygonization of the voxel phantom, organ modeling via NURBS surfaces and phantom voxelization. Two 3D graphic tools, 3D-DOCTOR and Rhinoceros, were utilized to polygonize the newborn voxel phantom and generate NURBS surfaces, while an in-house MATLAB code was used to voxelize the resulting NURBS model into a final computational phantom ready for use in Monte Carlo radiation transport calculations. A total of 126 anatomical organ and tissue models, including 38 skeletal sites and 31 cartilage sites, were described within the hybrid phantom using either NURBS or polygon surfaces. A male hybrid newborn phantom was constructed following the development of the female phantom through the replacement of female-specific organs with male-specific organs. The outer body contour and internal anatomy of the NURBS-based phantoms were adjusted to match anthropometric and reference newborn data reported by the International Commission on Radiological Protection in their Publication 89. The voxelization process was designed to accurately convert NURBS models to a voxel phantom with minimum volumetric change. A sensitivity study was additionally performed to better understand how the meshing tolerance and voxel resolution would affect volumetric changes between the hybrid-NURBS and hybrid-voxel phantoms. The male and female hybrid-NURBS phantoms were constructed in a manner so that all internal organs approached their ICRP reference masses to within 1%, with the exception of the skin (-6.5% relative error) and brain (-15.4% relative error). Both hybrid-voxel phantoms were constructed with an isotropic voxel resolution of 0.663 mm--equivalent to the ICRP 89 reference thickness of the newborn skin (dermis and epidermis). Hybrid-NURBS phantoms used to create their voxel counterpart retain the non-uniform scalability of stylized phantoms, while maintaining the anatomic realism of segmented voxel phantoms with respect to organ shape, depth and inter-organ positioning.

NURBS-based 3-D anthropomorphic computational phantoms for radiation dosimetry applications.

Computational anthropomorphic phantoms are computer models used in the evaluation of absorbed dose distributions within the human body. Currently, two classes of the computational phantoms have been developed and widely utilised for dosimetry calculation: (1) stylised (equation-based) and (2) voxel (image-based) phantoms describing human anatomy through the use of mathematical surface equations and 3-D voxel matrices, respectively. However, stylised phantoms have limitations in defining realistic organ contours and positioning as compared to voxel phantoms, which are themselves based on medical images of human subjects. In turn, voxel phantoms that have been developed through medical image segmentation have limitations in describing organs that are presented in low contrast within either magnetic resonance or computed tomography image. The present paper reviews the advantages and disadvantages of these existing classes of computational phantoms and introduces a hybrid approach to a computational phantom construction based on non-uniform rational B-spline (NURBS) surface animation technology that takes advantage of the most desirable features of the former two phantom types.

Variation in Practice Patterns for the Management of Newborn Spina Bifida in the United States.

OBJECTIVE: To survey variations in recommended initial management of newborn spina bifida (SB). METHODS: Members of an international pediatric urology ListServe and of the Pediatric Urology Nurse Specialists organization were surveyed on practice patterns for newborn SB. Pediatric urologists, nurse practitioners, and physician assistants practicing in the United States were included. RESULTS: A total of 63 practitioners (48% pediatric urologists and 52% nurse practitioners or physician assistants) were included. Most practice at tertiary hospitals (94%) and about half use a protocol (56%). Recommended in-hospital screening tests include renal ultrasound (95%), voiding cystourethrogram (52%), catheterized bladder volumes (56%), and renal function tests (37%). Urodynamics are deferred until follow-up by 71%. Fifty percent of practitioners initiate clean intermittent catheterization (CIC) on all newborns, whereas 43% wait for symptoms. The majority of those who start CIC continue until residual volumes are below a threshold. Few recommend prophylactic antibiotics routinely (13%), or in patients on CIC (19%), but most recommend it for urinary reflux (62% grades 1-2, 79% grade 3, and 87% grades 4-5). Anticholinergics are deferred until after urodynamics (68%). Practicing at an institution with a pediatric urology fellowship program or an SB treatment protocol was associated with differing diagnostic work-up and urologic management. CONCLUSION: There is variability in management of newborn SB among pediatric urology providers at tertiary care centers that may be influenced by institutional factors such as the presence of a pediatric urology fellowship or the presence of a protocol to care. This highlights the need for prospective multicenter projects to better understand how variations in management affect patient outcomes.

Patient characteristics associated with differences in radiation exposure from pediatric abdomen-pelvis CT scans: a quantile regression analysis.

BACKGROUND: Computed tomography (CT) is a widely used diagnostic tool in pediatric medicine. However, due to concerns regarding radiation exposure, it is essential to identify patient characteristics associated with higher radiation burden from CT imaging, in order to more effectively target efforts towards dose reduction. Our objective was to identify the effects of various demographic and clinical patient characteristics on radiation exposure from single abdomen/pelvis CT scans in children. METHODS: CT scans performed at our institution between January 2013 and August 2015 in patients under 16 years of age were processed using a software tool that estimates patient-specific organ and effective doses and merges these estimates with data from the electronic health record and billing record. Quantile regression models at the 50th, 75th, and 90th percentiles were used to estimate the effects of patients' demographic and clinical characteristics on effective dose. RESULTS: 2390 abdomen/pelvis CT scans (median effective dose 1.52mSv) were included. Of all characteristics examined, only older age, female gender, higher BMI, and whether the scan was a multiphase exam or an exam that required repeating for movement were significant predictors of higher effective dose at each quantile examined (all p<0.05). The effects of obesity and multiphase or repeat scanning on effective dose were magnified in higher dose scans. CONCLUSIONS: Older age, female gender, obesity, and multiphase or repeat scanning are all associated with increased effective dose from abdomen/pelvis CT. Targeted efforts to reduce dose from abdominal CT in these groups should be undertaken.

Lymphocyte depression as a predictor of postoperative intraabdominal abscess after appendectomy in children.

BACKGROUND: This study evaluated the efficacy of lymphopenia to predict postappendectomy intraabdominal abscess (IAA) in pediatric complex appendicitis. METHODS: This single-center retrospective cohort study included appendectomy patients with complex appendicitis from 4/2012 to 10/2014. IAA was diagnosed based on imaging or undergoing a drainage procedure. Labs were used from the closest day prior to abscess diagnosis or day of discharge from index admission. Lymphocyte percentage was categorized based on age-specific cutoffs with lymphopenia defined as a low percentage. Comparisons were made using chi-square or Fisher exact tests for categorical variables and Mann-Whitney U-tests for continuous variables. RESULTS: Of 611 appendectomy patients with complicated appendicitis, 551 had WBC and differential. IAA was identified in 79 (12.9%) patients. There were no significant differences in demographics between IAA and non-IAA groups. Patients with IAA had higher rates of leukocytosis (44.3% versus 12.3%, p<0.001) and higher rates of age-based lymphopenia (84% vs. 46%, p<0.001). IAA was independently associated with leukocytosis (OR 3.65, p<0.001) and lymphopenia (OR 4.46, p<0.001). Patients with leukocytosis and lymphopenia had the highest abscess rate (36%), and those with normal labs had the lowest (3%, p<0.001). CONCLUSIONS: Lymphocyte depression is a useful adjunct to predict postoperative IAA in patients with complicated appendicitis. LEVEL OF EVIDENCE: III.

A pilot study of ultrasound elastography as a non-invasive method to monitor liver disease in children with short bowel syndrome.

BACKGROUND: Our objective was to evaluate the accuracy of acoustic radiation force impulse (ARFI) elastography in determining extent of liver fibrosis in pediatric patients with short bowel syndrome (SBS). METHODS: This prospective cohort study included pediatric patients with SBS who underwent ultrasound with ARFI measurements of shear wave speed (SWS) and liver biopsy within 30days of each other between 12/2014-9/2015. The mean and median SWS were compared to the stage of fibrosis. Receiver operating characteristic curves (ROC) were also generated to assess the classification accuracy of SWS measurements for mild (F0-F1) versus moderate/severe fibrosis (F2-F4). RESULTS: Twelve patients were included with median age 1.4years and median weight 11.3kg. The median direct bilirubin level was 0.3mg/dL at the time of biopsy. On liver biopsy, 6 patients had mild fibrosis (F1), 3 had septal fibrosis (F3), and 3 had cirrhosis (F4). The area under the ROC curve for elastography to differentiate moderate/severe liver fibrosis from mild disease was 0.83 (95CI 0.58-1.00) and 0.86 (95CI 0.63-1.00) for the median SWS and mean SWS, respectively. CONCLUSIONS: These early results suggest that ARFI ultrasound elastography may be a reliable non-invasive method to monitor liver fibrosis in pediatric patients with SBS. TYPE OF STUDY: Prospective observational cohort. LEVEL OF EVIDENCE: 3.

Sacral nerve stimulation allows for decreased antegrade continence enema use in children with severe constipation.

BACKGROUND: Sacral nerve stimulation (SNS) can be beneficial for children with constipation, but no studies have focused on children with constipation severe enough to require antegrade continence enemas (ACEs). Our objective was to evaluate the efficacy of SNS in children with constipation treated with ACE. METHODS: Using a prospective patient registry, we identified patients <21years old who were receiving ACE prior to SNS placement. We compared ACE/laxative usage, PedsQL Gastrointestinal Symptom Scale (GSS), Fecal Incontinence Quality of Life Scale (FIQL), Fecal Incontinence Severity Index (FISI), and Vancouver Dysfunctional Elimination Syndrome Score (DES) at baseline and progressive follow-up time intervals. RESULTS: Twenty-two patients (55% male, median 12years) were included. Median ACE frequency decreased from 7 per week at baseline to 1 per week at 12months (p<0.0001). Ten children (45%) had their cecostomy/appendicostomy closed. Laxative use, GSS, FIQL, and DES did not change. FISI improved over the first 12months with statistical significance reached only at 6months (p=0.02). Six (27%) children experienced complications after SNS that required further surgery. CONCLUSIONS: In children with severe constipation dependent on ACE, SNS led to a steady decrease in ACE usage with nearly half of patients receiving cecostomy/appendicostomy closure within 2years. LEVEL OF EVIDENCE: IV.

Accuracy of radiographic estimation of small bowel dimensions in pediatric patients with short bowel syndrome.

BACKGROUND: The decision to perform autologous intestinal lengthening in patients with short bowel syndrome (SBS) depends on total bowel length and the diameter and length of dilated segments. This study evaluated the accuracy of radiologic measurements of intestinal length and diameter. METHODS: Patients who underwent an intestinal lengthening procedure with preoperative upper gastrointestinal study (UGI) were identified from 10/2012 through 1/2015. Measurements of total length and diameters and lengths of dilated segments on UGI were compared to intraoperative measurements using Spearman's rank correlation coefficients and Bland-Altman plots. RESULTS: Fourteen patients underwent 15 lengthening procedures. Median age was 3.6years. Most common causes of SBS were complicated gastroschisis (43%) and small bowel atresia (36%). Intra-operative bowel lengths prior to performing lengthening procedures ranged from 21 to 170cm. The median measurements of radiographic and operative measurements (respectively) were total bowel lengths 77cm and 69cm (r=0.93, p<0.0001), maximum diameters 7.7cm and 7cm (r=0.86, p=0.001), and lengths of dilated segments 13cm and 14cm (r=0.41, p=0.36). CONCLUSIONS: The correlation between UGI and operative measurements suggests that prediction of total bowel length and maximum diameter of dilation is accurate and can assist with operative planning.

High failure rate of nonoperative management of acute appendicitis with an appendicolith in children.

BACKGROUND: The purpose of this study was to investigate the feasibility of nonoperative management of acute appendicitis in children with an appendicolith identified on preoperative imaging. STUDY DESIGN: We performed a prospective nonrandomized trial of nonoperative management of uncomplicated acute appendicitis with an appendicolith in children aged 7 to 17years. The primary outcome was the failure rate of nonoperative management, defined as having undergone an appendectomy. Early termination was set to occur if the lower limit of the 95% confidence interval of the failure rate was greater than 20% at 30days or 30% at 1year. RESULTS: Recruitment for this study was halted after enrollment of 14 patients (N=5 nonoperative; N=9 surgery). The failure rate of nonoperative management was 60% (3/5) at a median follow-up of 4.7months (IQR 1.0-7.6) with a 95% CI of 23%-88%. None of the three patients that failed nonoperative management had complicated appendicitis at the time of appendectomy, while six out of nine patients who chose surgery had complicated appendicitis (0/3 vs. 6/9, p=0.18). The trial was stopped for concerns over patient safety. CONCLUSIONS: Nonoperative management of acute appendicitis with an appendicolith in children resulted in an unacceptably high failure rate.