Search

The radiology report in a case of suspected child abuse is both a medical and a legal document. Such reports should be thorough, specific, well-constructed and without error. Structured templates and standardized reporting contribute to completeness, consistency and communication. Here, the authors discuss common reporting errors. Radiologists should be prepared that the radiology report in a case of suspected child abuse is likely to be used in court.

Ehlers-Danlos syndrome is a real diagnosis that is erroneously used to explain multiple fractures in suspected child abuse. This paper reviews the clinical and molecular diagnostic criteria for Ehlers-Danlos syndrome. This knowledge can help prevent misdiagnosis and support clinicians when evaluating infants and young children with multiple fractures.

Please see the Editorial Comment by Katya Rozovsky discussing this article. BACKGROUND. Costochondral junction (CCJ) rib fractures pose a challenge in the radiographic detection and dating of infan...

PURPOSE: To evaluate the efficacy of convolutional neural networks (CNNs) to improve the image quality of low-dose pediatric abdominal CT images. MATERIALS AND METHODS: Images from 11 pediatric abdominal CT examinations acquired between June and July 2018 were reconstructed with filtered back projection (FBP) and an iterative reconstruction (IR) algorithm. A residual CNN was trained using the FBP image as the input and the difference between FBP and IR as the target such that the network was able to predict the residual image and simulate the IR. CNN-based postprocessing was applied to 20 low-dose pediatric image datasets acquired between December 2016 and December 2017 on a scanner limited to reconstructing FBP images. The FBP and CNN images were evaluated based on objective image noise and subjective image review by two pediatric radiologists. For each of five features, readers rated images on a five-point Likert scale and also indicated their preferred series. Readers also indicated their “overall preference” for CNN versus FBP. Preference and Likert scores were analyzed for individual and combined readers. Interreader agreement was assessed. RESULTS: The CT number remained unchanged between FBP and CNN images. Image noise was reduced by 31% for CNN images (P < .001). CNN was preferred for overall image quality for individual and combined readers. For combined Likert scores, at least one of the two score types (Likert or binary preference) indicated a significant favoring of CNN over FBP for low contrast, image noise, artifacts, and high contrast, whereas the reverse was true for spatial resolution. CONCLUSION: FBP images can be improved in image space by a well-trained CNN, which may afford a reduction in dose or improvement in image quality on scanners limited to FBP reconstruction. © RSNA, 2019

Background Contrast-enhanced MRI of the small bowel is an effective imaging sequence for the detection and characterization of disease burden in pediatric Crohn's disease (CD). However, visualization and quantification of disease burden requires scrolling back and forth through 3D images to follow the anatomy of the bowel, and it can be difficult to fully appreciate the extent of disease. Purpose To develop and evaluate a method that offers better visualization and quantitative assessment of CD from MRI. Study type Retrospective. Population Twenty-three pediatric patients with CD. Field strength/sequence 1.5T MRI system and T1 -weighted postcontrast VIBE sequence. Assessment The convolutional neural network (CNN) segmentation of the bowel's lumen, wall, and background was compared with manual boundary delineation. We assessed the reproducibility and the capability of the extracted markers to differentiate between different levels of disease defined after a consensus review by two experienced radiologists. Statistical tests The segmentation algorithm was assessed using the Dice similarity coefficient (DSC) and boundary distances between the CNN and manual boundary delineations. The capability of the extracted markers to differentiate between different disease levels was determined using a t-test. The reproducibility of the extracted markers was assessed using the mean relative difference (MRD), Pearson correlation, and Bland-Altman analysis. Results Our CNN exhibited DSCs of 75 ± 18%, 81 ± 8%, and 97 ± 2% for the lumen, wall, and background, respectively. The extracted markers of wall thickness at the location of min radius (P = 0.0013) and the median value of relative contrast enhancement (P = 0.0033) could differentiate active and nonactive disease segments. Other extracted markers could differentiate between segments with strictures and segments without strictures (P 3 times superior when computed on curved planar reformatting images compared with the conventional scheme. Data conclusion The results of this study show that the newly developed method is efficient for visualization and assessment of CD. Level of evidence 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1565-1576.

Objective Critically ill children with congenital heart disease (CHD) are at risk for metabolic bone disease (MBD) and bone fractures. Our objective was to characterize a cohort of CHD patients with fractures and describe a Fragile Bone Protocol (FBP) developed to reduce fractures. Design/Setting Patients who developed fractures in the Cardiac Intensive Care Unit (CICU) of Boston Children's Hospital from 3/2008 to 6/2014 were identified via quality improvement and radiology databases. The FBP (initiated July 2011) systematically identifies patients at risk for MBD and prescribes special handling precautions. Results Twenty-three fractures were identified in 15 children. Median age at fracture identification was 6.2 months, with a median duration of hospitalization before fracture diagnosis of 2.7 months. Six patients (40%) had single ventricle CHD. Hyperparathyroidism and low 25-OH vitamin D levels were present in 77% and 40% of those tested, respectively. Compared with patients not diagnosed with fractures, fracture patients had increased exposure to possible risk factors for MBD and had elevated parathyroid and decreased calcitriol levels.Six patients (40%) did not survive to hospital discharge, compared with an overall CICU mortality rate of 2.6% (P < .01). The fracture case rate before implementation of the FBP was 2.6 cases/1000 admissions and was 0.7/1000 after implementation of the FBP (P = .04). Conclusions Critically ill CHD patients are at risk for fractures. They represent a complex group who frequently has hyperparathyroidism and decreased calcitriol levels, and each may predispose to fractures. FBPs consisting of identification and careful patient handling should be considered in at-risk patients.

To determine if rickets is present in cases of infant homicide with classic metaphyseal lesions (CMLs) and other skeletal injuries.This study was exempt from the institutional human subjects board review because all infants were deceased. An archival review (1984-2012) was performed of the radiologic and histopathologic findings of 46 consecutive infant fatalities referred from the state medical examiner's office for the evaluation of possible child abuse. Thirty infants with distal femoral histologic material were identified. Additional inclusion criteria were as follows: (a) The medical examiner determined that the infant had sustained a head injury and that the manner of death was a homicide, (b) at least one CML was evident at skeletal survey, (c) CMLs were confirmed at autopsy, and (d) non-CML fractures were also present. Nine infants (mean age, 3.9 months; age range, 1-9 months) were identified. Two pediatric radiologists independently reviewed the skeletal surveys for rachitic changes at the wrists and knees. A bone and soft tissue pathologist reviewed the distal femoral histologic slices for rickets.There were no radiographic or pathologic features of rickets in the cohort.The findings provide no support for the view that the CML is due to rickets. Rather, they strengthen a robust literature that states that the CML is a traumatic injury commonly encountered in physically abused infants.

Purpose: To evaluate the effect of the spatially constrained incoherent motion (SCIM) method on improving the precision and robustness of fast and slow diffusion parameter estimates from diffusion-weighted MRI in liver and spleen in comparison to the independent voxel-wise intravoxel incoherent motion (IVIM) model. Methods: We collected diffusion-weighted MRI (DW-MRI) data of 29 subjects (5 healthy subjects and 24 patients with Crohn’s disease in the ileum). We evaluated parameters estimates’ robustness against different combinations of b-values (i.e., 4 b-values and 7 b-values) by comparing the variance of the estimates obtained with the SCIM and the independent voxel-wise IVIM model. We also evaluated the improvement in the precision of parameter estimates by comparing the coefficient of variation (CV) of the SCIM parameter estimates to that of the IVIM. Results: The SCIM method was more robust compared to IVIM (up to 70% in liver and spleen) for different combinations of b-values. Also, the CV values of the parameter estimations using the SCIM method were significantly lower compared to repeated acquisition and signal averaging estimated using IVIM, especially for the fast diffusion parameter in liver (CVIV IM = 46.61 ± 11.22, CVSCIM = 16.85 ± 2.160, p < 0.001) and spleen (CVIV IM = 95.15 ± 19.82, CVSCIM = 52.55 ± 1.91, p < 0.001). Conclusions: The SCIM method characterizes fast and slow diffusion more precisely compared to the independent voxel-wise IVIM model fitting in the liver and spleen.

The distal tibia is a common location for the classic metaphyseal lesion (CML). Prior radiologic-pathologic studies have suggested a tendency for medial, as opposed to lateral, cortical injury with the CML, but there has been no formal study of the geographic distribution of this strong indicator of abuse. This study compares medial versus lateral cortical involvement of distal tibial CMLs in a clinical cohort of infants with suspected abuse. Reports of 1,020 skeletal surveys performed for suspected abuse (July 2005-June 2016) were reviewed. Twenty-six distal tibial CMLs (14 unilateral, 6 bilateral) with anteroposterior (AP) and lateral projections on the initial skeletal survey and at least an AP view on the follow-up survey were identified in 20 infants. Two blinded pediatric radiologists determined if the medial and/or lateral margins of the distal tibial metaphysis were involved by the CML. Average interreader absolute agreement and kappa scores were 0.69-0.90 and 0.45-0.72, respectively. Average intrareader absolute agreement and kappa scores were 0.65-0.88 and 0.44-0.57, respectively. Analyses showed that the distal tibial CML almost always involved the medial cortical margin (reader 1=89%, reader 2=88%, pooled=89%) and the fracture infrequently involved the lateral cortical margin (reader 1=12%, reader 2=38%, pooled=26%). The percentage point difference between fracture involvement in medial and lateral margins was statistically significant from zero (P

OBJECTIVE: To describe a skeletal survey data entry and compilation tool and assess physician attitudes toward this reporting approach. BACKGROUND: Narrative skeletal survey reports are highly variable and prone to inconsistencies with potential adverse impact on patients. MATERIALS AND METHODS: The prototype skeletal survey data entry and compilation tool was developed and introduced into clinical practice at a large urban children's hospital. Pediatric radiologists and child protection team (CPT) pediatricians completed a survey of reporting preferences. Skeletal survey reports between March 1, 2013, and March 1, 2014, were reviewed to assess use of the tool. RESULTS: The survey response rate was 70% (14/20) for radiologists and 100% (4/4) for CPT pediatricians. Among responding radiologists, 54.5% (6/11) indicated that a skeletal survey data entry and compilation tool was helpful for skeletal surveys with >3 fractures; 80% (8/10) of responding radiologists indicated that tabulated data from prior skeletal survey was helpful when interpreting a follow-up skeletal survey with >3 fractures; 90.9% (10/11) of radiologists thought the tool improved report organization; 72.7% (8/11) thought it improved accuracy. Most radiologists (11/12, 91.7%) and 100% (4/4) of CPT clinicians preferred reports with both free text and a tabulated fracture list for testifying in court when >3 fractures were present. The tool was used in the reporting of 14/23 (61%) skeletal surveys with >3 fractures during a 1-year period. A case example using the application is presented. CONCLUSION: Most radiologists and CPT physicians at our center prefer skeletal survey reports with tabulated data and narrative description; 91.7% (11/12) of radiologists and all CPT clinicians prefer this approach for testifying in court when >3 fractures are present. Language: en

Fractures are common injuries caused by child abuse. Although the consequences of failing to diagnose an abusive injury in a child can be grave, incorrectly diagnosing child abuse in a child whose fractures have another etiology can be distressing for a family. The aim of this report is to review recent advances in the understanding of fracture specificity, the mechanism of fractures, and other medical diseases that predispose to fractures in infants and children. This clinical report will aid physicians in developing an evidence-based differential diagnosis and performing the appropriate evaluation when assessing a child with fractures.

Spinal fractures are uncommon manifestations of child abuse and elimination of the lateral views of the spine from the initial skeletal survey protocol has been recommended. To establish the prevalence of spinal fractures detected on skeletal surveys performed for suspected child abuse and their association with intracranial injury (ICI). The ACR standardized skeletal surveys and neuroimaging studies of 751 children (ages 0–4 years) were reviewed. A positive skeletal survey was defined as having one or more clinically unsuspected fractures. Fourteen children had a total of 22 definite spinal fractures. This constituted 1.9% (14/751) of the total cohort, and 9.7% (14/145) of children with a positive skeletal survey. Advanced imaging confirmed the fractures in 13 of the 14 children and demonstrated 12 additional spinal fractures. In five cases, spinal fractures were the only positive skeletal findings. In 71% (10/14) of the children, the spinal fractures were accompanied by ICI. Children with spinal fractures were at significantly greater risk for ICI than those without spinal injury (P

Quantitative diffusion-weighted MR imaging (DW-MRI) of the body enables characterization of the tissue microenvironment by measuring variations in the mobility of water molecules. The diffusion signal decay model parameters are increasingly used to evaluate various diseases of abdominal organs such as the liver and spleen. However, previous signal decay models (i.e., mono-exponential, bi-exponential intra-voxel incoherent motion (IVIM) and stretched exponential models) only provide insight into the average of the distribution of the signal decay rather than explicitly describe the entire range of diffusion scales. In this work, we propose a probability distribution model of incoherent motion that uses a mixture of Gamma distributions to fully characterize the multi-scale nature of diffusion within a voxel. Further, we improve the robustness of the distribution parameter estimates by integrating spatial homogeneity prior into the probability distribution model of incoherent motion (SPIM) and by using the fusion bootstrap solver (FBM) to estimate the model parameters. We evaluated the improvement in quantitative DW-MRI analysis achieved with the SPIM model in terms of accuracy, precision and reproducibility of parameter estimation in both simulated data and in 68 abdominal in-vivo DW-MRIs. Our results show that the SPIM model not only substantially reduced parameter estimation errors by up to 26%; it also significantly improved the robustness of the parameter estimates (paired Student's t-test, p < 0.0001) by reducing the coefficient of variation (CV) of estimated parameters compared to those produced by previous models. In addition, the SPIM model improves the parameter estimates reproducibility for both intra- (up to 47%) and inter-session (up to 30%) estimates compared to those generated by previous models. Thus, the SPIM model has the potential to improve accuracy, precision and robustness of quantitative abdominal DW-MRI analysis for clinical applications.

Purpose: To characterize fast and slow diffusion components in diffusion-weighted magnetic resonance imaging (DW-MRI) of pediatric Crohn's disease (CD). Overall diffusivity reduction as measured by the apparent diffusion coefficient (ADC) in patients with CD has been previously demonstrated. However, the ADC reduction may be due to changes in either fast or slow diffusion components. In this study we distinguished between the fast and slow diffusion components in the DW-MRI signal decay of pediatric CD. Materials and Methods: We acquired MRI from 24 patients, including MR enterography (MRE) and DW-MRI with 8 b-values (0–800 s/mm2). We characterized fast and slow diffusivity by intravoxel incoherent motion (IVIM) model parameters (f, D*, D), and overall diffusivity by ADC values. We determined which model best described the DW-MRI signal decay. We assessed the influence of the IVIM model parameters on the ADC. We evaluated differences in model parameter values between the enhancing and nonenhancing groups. Results: The IVIM model described the observed data significantly better than the ADC model (P = 0.0088). The ADC was correlated with f (r = 0.67, P = 0.0003), but not with D (r = 0.39, P = 0.062) and D* (r = −0.39, P = 0.057). f values were significantly lower (P < 0.003) and D* values were significantly higher (P = 0.03) in the enhancing segments, while D values were not significantly different between the groups (P = 0.14). Conclusion: For this study population the IVIM model provides a better description of the DW-MRI signal decay than the ADC model. The reduced ADC is related to changes in the fast diffusion rather than to changes in the slow diffusion. J. Magn. Reson. Imaging 2013;37:156–163. © 2012 Wiley Periodicals, Inc.

Purpose: To assess the optimal b-values range for perfusion-insensitive apparent diffusion coefficient (ADC) imaging of abdominal organs using short-duration DW-MRI acquisitions with currently available ADC estimation methods. Methods: DW-MRI data of 15 subjects were acquired with eight b-values in the range of 5–800 s/mm2. The reference-standard, a perfusion insensitive, ADC value (ADCIVIM), was computed using an intravoxel incoherent motion (IVIM) model with all acquired diffusion-weighted images. Simulated DW-MRI data was generated using an IVIM model with b-values in the range of 0–1200 s/mm2. Monoexponential ADC estimates were calculated using: (1) Two-point estimator (ADC2); (2) least squares three-point (ADC3) estimator and; (3) Rician noise model estimator (ADCR). The authors found the optimal b-values for perfusion-insensitive ADC calculations by minimizing the relative root mean square error (RRMS) between the ADCIVIM and the monoexponential ADC values for each estimation method and organ. Results: Low b-value = 300 s/mm2 and high b-value = 1200 s/mm2 minimized the RRMS between the estimated ADC and the reference-standard ADCIVIM to less than 5% using the ADC3 estimator. By considering only the in vivo DW-MRI data, the combination of low b-value = 270 s/mm2 and high b-value of 800 s/mm2 minimized the RRMS between the estimated ADC and the reference-standard ADCIVIM to

To examine radiographic findings in children with vitamin D deficiency in comparison with biochemical marker levels and prevalence of fractures.The parents or guardians of all participants provided written informed consent at the time of enrollment. The institutional review board approved the protocol, and HIPAA guidelines were followed. From a prospective sample of children seen for routine clinical care, 40 children with vitamin D deficiency (25-hydroxyvitamin D [25-OHD] level, ≤ 20 ng/mL) were identified, and high-detail computed radiographs of the wrists and knees were obtained. The children ranged in age from 8 to 24 months. Radiographs were scored by three readers with use of the 10-point Thacher score for rachitic changes and a five-point scale for demineralization. Serum calcium, phosphorus, alkaline phosphatase, and parathyroid hormone levels were determined. Fracture history was obtained for 35 of the 40 patients (88%).All readers identified rachitic changes at both readings in two patients (5%) and demineralization in two patients (5%). Interrater agreement was 65% for rachitic changes (κ = 0.33) and 70% for demineralization (κ = 0.37). When the majority of the raters determined that rachitic changes were absent at both readings, alkaline phosphatase levels were lower than those with other assessments (median, 267 vs 515 U/L [4.4589 vs 8.6005 μkat/L]; P = .01). When most raters determined that demineralization was present at both readings, serum 25-OHD levels were lower than those at other assessments (median, 9.0 vs 17.5 ng/mL [22.464 vs 43.68 nmol/L]; P = .02). No fractures were reported or identified radiographically.In infants and toddlers with vitamin D deficiency, rachitic changes and definite demineralization are uncommon and fracture risk is low.

The purpose of this article is to determine the relative likelihood of encountering a classic metaphyseal lesion in infants at low and high risk for abuse.This 10-year retrospective study compared the prevalence of the classic metaphyseal lesion on high-detail American College of Radiology-standardized skeletal surveys in infants at low and high risk for abuse. Low-risk infants met all of the following criteria: skull fracture without significant intracranial injury on CT, history of a fall, and no other social risk factors for abuse. High-risk infants met all of the following criteria: significant intracranial injury, retinal hemorrhages, and skeletal injuries (excluding classic metaphyseal lesions and skull fractures). Differences between the two groups were calculated using the Fisher exact test.There were 42 low-risk infants (age range, 0.4-12 months; mean age, 4.4 months) and 18 high-risk infants (age range, 0.8-10.3 months; mean age, 4.6 months). At least one classic metaphyseal lesion was identified in nine infants (50%) in the high-risk category. No classic metaphyseal lesions were identified in the low-risk group. The relative prevalence of classic metaphyseal lesions in the low-risk group (0/42) versus that in the high-risk group (9/18) was statistically significant (p0.0001; 95% CI, 0-8% to 29-76%).Classic metaphyseal lesions are commonly encountered in infants at high risk for abuse and are rare in infants with skull fractures associated with falls, but no other risk factors. The findings support the view that the classic metaphyseal lesion is a high-specificity indicator of infant abuse.

We prospectively evaluated the precision of ultrasound and computerized tomography to diagnose urinary stones in children and determined whether these differences in radiological findings have any impact on clinical management.A total of 50 consecutive patients with suspected urolithiasis underwent computerized tomography and ultrasound. Two radiologists reviewed each study independently in blinded fashion. When a difference in findings was detected, 8 pediatric urologists reviewed the case. Clinical management was based on the results of each radiological test independently. Statistical analysis was performed using Fisher's exact test.Compared to computerized tomography ultrasound had 76% sensitivity and 100% specificity. In 8 patients stone(s) seen on computerized tomography was not seen on ultrasound. The average size of missed stones was 2.3 mm. In 7 patients computerized tomography showed stones bilaterally but stone was seen on only 1 side on ultrasound. When evaluating the clinical impact, the ultrasound/computerized tomography discrepancy did not result in any significant change in clinical management except in 4 cases. In these cases ultrasound findings suggested that additional imaging was required and, thus, stone(s) in the distal ureter would have been identified on subsequent imaging.Although computerized tomography is more sensitive for detecting urolithiasis than ultrasound, the difference in usefulness between the 2 radiological tests may not be clinically significant. Given concerns for the potentially harmful cumulative long-term effect of radiation, ultrasound should be considered the first imaging test in children with suspected urolithiasis.

OBJECTIVE. The purpose of this study was to examine imaging findings that differentiate inflicted injuries from developmental variants of the superior pubic ramus in healthy and abused infants.CONCLUSION. A superior pubic ramus fracture and a developmental variant can be difficult to differentiate radiographically. A smoothly marginated vertical radiolucency of the superior pubic ramus detected without other features suggesting infant abuse should not be interpreted as a fracture.

Introduction Infants and children with metabolic bone diseases are at increased risk of fractures. Demineralization is an observation that alerts the radiologist to the possibility of an underlying disturbance of calcium and phosphorus metabolism. Demineralization or osteopenia are descriptive (qualitative) terms that can be seen in a variety of conditions causing osteoporosis or osteomalacia; for purposes of simplicity, they will be used interchangeably in this chapter (1–4). In osteoporosis there is normal mineralization of physeal cartilage (see Chapters 1 and 2); the demineralization is due to decrease osteoid matrix. However, the diagnosis of osteoporosis in children requires the presence of a clinically significant fracture and low bone mineral content (BMC) and the term “decreased osteoid matrix” is preferred by some (5). Osteomalacia occurs when there is lack of minerals available for adequate mineralization of osteoid matrix and, thus, there is an accumulation of unmineralized bone matrix. Rickets occurs when the endochondral mineralization at the physes is disturbed, leading to the characteristic pathologic and radiographic findings to be described. Rickets is associated with osteomalacia in children; osteomalacia alone is found once the physes have fused (Fig. 8.1). The most common cause of osteomalacia in children is vitamin D deficiency rickets but there are several other forms of the disease including hypophosphatemic rickets (vitamin D-resistant rickets) and disorders of vitamin D synthesis and/or action. This chapter focuses on osteomalacia and rickets in the infants and young children where the primary manifestations of the metabolic disturbance (metaphyseal irregularities) and superimposed fractures are relevant to the differential diagnosis of abuse. Rickets is also discussed elsewhere in the context of miscellaneous form of abuse and neglect (see Chapter 23).

Critically ill children with congenital heart disease (CHD) are at risk for metabolic bone disease (MBD) and bone fractures. Our objective was to characterize a cohort of CHD patients with fractures and describe a Fragile Bone Protocol (FBP) developed to reduce fractures.Patients who developed fractures in the Cardiac Intensive Care Unit (CICU) of Boston Children's Hospital from 3/2008 to 6/2014 were identified via quality improvement and radiology databases. The FBP (initiated July 2011) systematically identifies patients at risk for MBD and prescribes special handling precautions.Twenty-three fractures were identified in 15 children. Median age at fracture identification was 6.2 months, with a median duration of hospitalization before fracture diagnosis of 2.7 months. Six patients (40%) had single ventricle CHD. Hyperparathyroidism and low 25-OH vitamin D levels were present in 77% and 40% of those tested, respectively. Compared with patients not diagnosed with fractures, fracture patients had increased exposure to possible risk factors for MBD and had elevated parathyroid and decreased calcitriol levels.Six patients (40%) did not survive to hospital discharge, compared with an overall CICU mortality rate of 2.6% (P.01). The fracture case rate before implementation of the FBP was 2.6 cases/1000 admissions and was 0.7/1000 after implementation of the FBP (P = .04).Critically ill CHD patients are at risk for fractures. They represent a complex group who frequently has hyperparathyroidism and decreased calcitriol levels, and each may predispose to fractures. FBPs consisting of identification and careful patient handling should be considered in at-risk patients.

To evaluate the effect of the spatially constrained incoherent motion (SCIM) method on improving the precision and robustness of fast and slow diffusion parameter estimates from diffusion-weighted MRI in liver and spleen in comparison to the independent voxel-wise intravoxel incoherent motion (IVIM) model.We collected diffusion-weighted MRI (DW-MRI) data of 29 subjects (5 healthy subjects and 24 patients with Crohn's disease in the ileum). We evaluated parameters estimates' robustness against different combinations of b-values (i.e., 4 b-values and 7 b-values) by comparing the variance of the estimates obtained with the SCIM and the independent voxel-wise IVIM model. We also evaluated the improvement in the precision of parameter estimates by comparing the coefficient of variation (CV) of the SCIM parameter estimates to that of the IVIM.The SCIM method was more robust compared to IVIM (up to 70% in liver and spleen) for different combinations of b-values. Also, the CV values of the parameter estimations using the SCIM method were significantly lower compared to repeated acquisition and signal averaging estimated using IVIM, especially for the fast diffusion parameter in liver (CVIV IM = 46.61 ± 11.22, CVSCIM = 16.85 ± 2.160, p0.001) and spleen (CVIV IM = 95.15 ± 19.82, CVSCIM = 52.55 ± 1.91, p0.001).The SCIM method characterizes fast and slow diffusion more precisely compared to the independent voxel-wise IVIM model fitting in the liver and spleen.

OBJECTIVE. The purpose of this study was to describe the varied appearances of metaphyseal fragmentation associated with physiologic bowing and to estimate their frequency in children undergoing radiographic evaluation.CONCLUSION. The results of this study suggest that metaphyseal fragmentation is occasionally encountered in children with physiologic bowing. Results of a systematic imaging assessment should minimize confusion of this innocent radiologic alteration with the classic metaphyseal lesion of child abuse.

Diffusion-weighted MRI of the body has the potential to provide important new insights into physiological and microstructural properties. The Intra-Voxel Incoherent Motion (IVIM) model relates the observed DW-MRI signal decay to parameters that reflect perfusivity (D*) and its volume fraction (f), and diffusivity (D). However, the commonly used voxel-wise fitting of the IVIM model leads to parameter estimates with poor precision, which has hampered their practical usage. In this work, we increase the estimates' precision by introducing a model of spatial homogeneity, through which we obtain estimates of model parameters for all of the voxels at once, instead of solving for each voxel independently. Furthermore, we introduce an efficient iterative solver which utilizes a model-based bootstrap estimate of the distribution of residuals and a binary graph cut to generate optimal model parameter updates. Simulation experiments show that our approach reduces the relative root mean square error of the estimated parameters by 80% for the D* parameter and by 50% for the f and D parameters. We demonstrated the clinical impact of our model in distinguishing between enhancing and nonenhancing ileum segments in 24 Crohn's disease patients. Our model detected the enhanced segments with 91%/92% sensitivity/specificity which is better than the 81%/85% obtained by the voxel-independent approach.

The value of 3-D skull models in evaluation of young children with suspected child abuse is not known. The purpose of this study was to assess the value of 3-D skull models as a problem-solving tool in children younger than 2 years. We performed a retrospective study on 73 children (ages 0–24 months) seen by a child protection team (CPT) who were undergoing head CT between August 2007 and July 2009. Of the 73 children, volume-rendered 3-D models were obtained in 26 (35.6%). Three-dimensional models changed initial CT interpretation in nine instances (34.6%). Findings thought to be fractures were confirmed as normal variants in four children. Depressed fractures were correctly shown to be ping-pong fractures in two cases. In one case, an uncertain finding was confirmed as a fracture, and an additional contralateral fracture was identified in one child. A fracture seen on skull radiographs but not seen on axial CT images was identified on the 3-D model in one case. Changes in interpretation led to modification in management in five children. Use of 3-D skull models can be a problem-solving tool when there is discordance among the CT reading, subsequent radiographic investigations and clinical evaluation.

Diffusion-weighted MRI has the potential to provide important new insights into physiological and microstructural properties of the body. The Intra-Voxel Incoherent Motion (IVIM) model relates the observed DW-MRI signal decay to parameters that reflect blood flow in the capillaries (D*), capillaries volume fraction (f), and diffusivity (D). However, the commonly used, independent voxel-wise fitting of the IVIM model leads to imprecise parameter estimates, which has hampered their practical usage. In this work, we improve the precision of estimates by introducing a spatially-constrained Incoherent Motion (IM) model of DW-MRI signal decay. We also introduce an efficient iterative "fusion bootstrap moves" (FBM) solver that enables precise parameter estimates with this new IM model. This solver updates parameter estimates by applying a binary graph-cut solver to fuse the current estimate of parameter values with a new proposal of the parameter values into a new estimate of parameter values that better fits the observed DW-MRI data. The proposals of parameter values are sampled from the independent voxel-wise distributions of the parameter values with a model-based bootstrap resampling of the residuals. We assessed both the improvement in the precision of the incoherent motion parameter estimates and the characterization of heterogeneous tumor environments by analyzing simulated and in vivo abdominal DW-MRI data of 30 patients, and in vivo DW-MRI data of three patients with musculoskeletal lesions. We found our IM-FBM reduces the relative root mean square error of the D* parameter estimates by 80%, and of the f and D parameter estimates by 50% compared to the IVIM model with the simulated data. Similarly, we observed that our IM-FBM method significantly reduces the coefficient of variation of parameter estimates of the D* parameter by 43%, the f parameter by 37%, and the D parameter by 17% compared to the IVIM model (paired Student's t-test, p0.0001). In addition, we found our IM-FBM method improved the characterization of heterogeneous musculoskeletal lesions by means of increased contrast-to-noise ratio of 19.3%. The IM model and FBM solver combined, provide more precise estimate of the physiological model parameter values that describing the DW-MRI signal decay and a better mechanism for characterizing heterogeneous lesions than does the independent voxel-wise IVIM model.

The purpose of our study was to examine the utility of whole-body MRI (WB-MRI) in the detection of skeletal and soft-tissue injuries in suspected infant abuse.Twenty-one infants (0-12 months) underwent WB-MRI for evaluation of suspected child abuse. WB-MRI at 1.5 T was performed using coronal and sagittal STIR sequences within 5 days of initial skeletal survey. Follow-up skeletal survey was performed in 16 cases. The "truth" was determined by integrating the initial and follow-up skeletal surveys, where available, into a summary of skeletal injuries (summary skeletal survey). Statistics included analysis of counts and proportions, concordance rate, sensitivity, and specificity.Summary skeletal survey and WB-MRI identified 167 fractures or areas of skeletal signal abnormality: 46 (27.5%) by both techniques, 68 (40.7%) by summary skeletal survey only, and 53 (31.7%) by WB-MRI only. WB-MRI had high specificity (95%) but low sensitivity (40%) for identifying fractures or signal abnormalities compared with summary skeletal survey. Thirty-seven classic metaphyseal lesions or metaphyseal signal abnormalities were identified: 11 (29.7%) by both techniques, 24 (64.8%) by summary skeletal survey only, and two (5.4%) by WB-MRI only. WB-MRI had very low sensitivity (31%) for identifying signal abnormality where classic metaphyseal lesions were seen with skeletal survey. WB-MRI had low sensitivity (57%) for identifying signal abnormality in areas where rib fractures were seen on skeletal survey. WB-MRI identified soft-tissue injuries such as muscle edema and joint effusions that, in some cases, led to identifying additional fractures.WB-MRI is insensitive in the detection of classic metaphyseal lesions and rib fractures, high specificity indicators of infant abuse. WB-MRI cannot replace the skeletal survey but may complement it by identifying soft-tissue abnormalities.

To evaluate the sensitivity of fluorine 18-labeled sodium fluoride ((18)F-NaF) positron emission tomography (PET) for assessment of skeletal trauma in pediatric patients suspected of having been abused and to compare the diagnostic performance of this examination with that of high-detail skeletal survey.The institutional review board approved this retrospective study and determined that it was in accordance with regulations of HIPAA privacy rule 45, Code of Federal Regulations parts 160 and 164, and that the criteria for waived patient authorization were met. The baseline skeletal survey and PET images obtained in 22 patients younger than 2 years between September 2007 and January 2009 were reviewed. Fourteen patients also underwent follow-up skeletal survey. The PET images were interpreted by two pediatric nuclear medicine physicians. The initially obtained skeletal survey images were interpreted blindly by a pediatric radiologist. A second pediatric radiologist interpreted the follow-up skeletal survey images in conjunction with the baseline survey images and rendered a final interpretation for the 14 patients in whom both baseline and follow-up skeletal survey data were available, which served as the reference standard.A total of 156 fractures were detected at baseline skeletal survey, and 200 fractures were detected at PET. Compared with the reference standard (findings in the 14 patients who underwent baseline and follow-up skeletal survey), PET had sensitivities of 85% for the detection of all fractures, 92% for the detection of thoracic fractures (ribs, sternum, clavicle, and scapula), 93% for the detection of posterior rib fractures, and 67% for the detection of classic metaphyseal lesions (CMLs), defined as a series of microfractures across the metaphysis. Compared with the reference standard, baseline skeletal survey had sensitivities of 72% for the detection of all fractures, 68% for the detection of thoracic fractures, 73% for the detection of posterior rib fractures, and 80% for the detection of CMLs.(18)F-NaF PET had greater sensitivity in the overall detection of fractures related to child abuse than did baseline skeletal survey. (18)F-NaF PET was superior in the detection of rib fractures in particular. Thus, (18)F-NaF PET is an attractive choice for evaluation of suspected child abuse, an application in which high sensitivity is desirable. Because of the lower sensitivity of PET in the detection of CMLs, a characteristic fracture in child abuse, initial radiographic evaluation remains necessary.

To determine the prevalence of vitamin D deficiency and to examine whether 25-hydroxyvitamin D (25OHD) concentration varies as a function of skin pigmentation, season, sun exposure, breastfeeding, and vitamin D supplementation.Cross-sectional sample.Urban primary care clinic.Healthy infants and toddlers (N = 380) who were seen for a routine health visit.Primary outcomes were serum 25OHD and parathyroid hormone levels; secondary measures included data on sun exposure, nutrition, skin pigmentation, and parental health habits. Wrist and knee radiographs were obtained for vitamin D-deficient participants.The prevalence of vitamin D deficiency (or =20 ng/mL) was 12.1% (44 of 365 participants), and 146 participants (40.0%) had levels below an accepted optimal threshold (or =30 ng/mL). The prevalence did not vary between infants and toddlers or by skin pigmentation. There was an inverse correlation between serum 25OHD and parathyroid hormone levels (infants: r = -0.27, P.001; toddlers: r = -0.20, P = .02). In multivariable models, breastfeeding without supplementation among infants and lower milk intake among toddlers were significant predictors of vitamin D deficiency. In vitamin D-deficient participants, 3 participants (7.5%) exhibited rachitic changes on radiographs, whereas 13 (32.5%) had evidence of demineralization.Suboptimal vitamin D status is common among otherwise healthy young children. Predictors of vitamin D status vary in infants vs toddlers, information that is important to consider in the care of these young patients. One-third of vitamin D-deficient participants exhibited demineralization, highlighting the deleterious skeletal effects of this condition.

Symptoms are commonly nonspecific in children with acute pyelonephritis; therefore, other diagnoses may be considered first. Skeletal scintigraphy revealed abnormal tracer distribution in the left kidney of a 7-year-old girl suspected of having acute osteomyelitis. A diagnosis of acute pyelonephritis was suggested and later supported by computed tomography and urine culture.

Os calcaneus secundarius is an uncommon anatomic variant that usually has no symptoms. The authors describe a patient with foot pain in whom plain radiographs and computed tomography suggested an os calcaneus secundarius. Skeletal scintigraphy, by showing high uptake at the corresponding site, supported its contributory role in explaining the patient's symptoms.