Diana P. Rodriguez

Imaging of Back Pain in Children

SUMMARY: While back pain presents less frequently in children than in adults, it still poses a significant clinical challenge with respect to making a firm diagnosis and developing an effective treatment plan. When children have back pain and medical attention is sought, an underlying pathology is usually suspected. Pediatric patients are evaluated, first, with a complete clinical history and examination and, second, by an imaging work-up that is based on initial findings, including the childs age and size, signs and symptoms, and suspected etiology. This article describes 1) the epidemiology of back pain in children, 2) the imaging work-up used, and 3) the correlation of imaging findings with disease entities that may cause back pain in the pediatric patient. The list of diseases giving rise to back pain is not meant to be exhaustive but rather reflective of the most commonly identified pathologies and disorders among young children and adolescents, from athletic injuries to lethal cancers.

Incidence of Epidural Catheter-associated Infections after Continuous Epidural Analgesia in Children

Clinical observation suggests that the number of serious epidural catheter-associated infections have increased recently in children. This increase is likely attributed to an increase in reporting and in frequency of epidural analgesia usage. Estimates of infection rates are difficult to determine primarily because of insufficient study of large pediatric populations. In this retrospective study, the authors investigated the incidence of epidural catheter-associated soft tissue and epidural infections after use of continuous epidural analgesia spanning 17 yr. A total of 10,653 epidural catheters were used in 7,792 children. The majority of catheters, 10,437 (98%), were placed for the management of postoperative pain, and 216 (2%) were placed for the management of chronic pain. The authors identified 13 cases of infections (nine cellulitis, two paravertebral musculature infections, one epidural inflammation, and one epidural abscess) between 3 and 11 days after catheter insertion. The incidence of infection was significantly higher in patients treated for chronic pain (7 of 216 = 3.2%) compared with postoperative pain (6 of 10,437 = 0.06%; P < 0.0001). Surgical drainage of subcutaneous pus was performed in three patients, and medical therapy was administered in the remainder of patients; all patients recovered without sequelae. Although rare, epidural catheter-associated infections remain a serious concern in high-risk children who may benefit the most from epidural analgesia. The findings of the authors support the low rate of epidural infection previously reported despite growing concerns of serious infections in children. These findings highlight the importance of vigilance to early diagnostic indicators of infection and provide practitioners and families with incidence data to guide informed medical decision-making.

Appendicitis in Young Children: Imaging Experience and Clinical Outcomes

OBJECTIVE Our purpose was to evaluate the imaging characteristics and clinical outcomes of children less than 5 years old who underwent surgery for presumed appendicitis. CONCLUSION Appendicitis is not rare in young children and imaging findings reflect the high frequency of perforation in this population.

Post-closed reduction perfusion magnetic resonance imaging as a predictor of avascular necrosis in developmental hip dysplasia: a preliminary report.

Introduction: Avascular necrosis (AVN) of the femoral head remains a major complication in the treatment of developmental dysplasia of the hip (DDH) in infants. We performed a retrospective analysis to look at the predictive ability of postclosed reduction contrast-enhanced magnetic resonance imaging (MRI) for AVN after closed reduction in DDH. Methods: Twenty-eight hips in 27 infants (aged 1-11 months) with idiopathic hip dislocations who had failed brace treatment underwent closed reduction ± adductor tenotomy and spica cast application under general anesthesia. Magnetic resonance imaging of the hips after intravenous gadolinium contrast injection for evaluation of epiphyseal perfusion was obtained immediately after cast application. Patients were followed with serial radiographs for a minimum of 1 year after closed reduction. Presence of AVN was determined by the presence of any one of the 5 Salter criteria by 2 readers. Magnetic resonance imaging was graded as normal, asymmetric enhancement, focal decreased enhancement, or global decreased enhancement by 2 radiologists. Results: Six (21%) of 28 hips showed evidence of clinically significant AVN on follow-up radiographs. Fifty percent of the hips with AVN, but only 2 of 22 hips without AVN, showed a global decreased MRI enhancement (P < 0.05, Fisher exact test). Multivariate logistic regression indicated that a global decreased enhancement was associated with a significantly higher risk of developing AVN (P < 0.01), independently of age at reduction (P = 0.02) and abduction angle. Conclusions: In addition to accurate anatomical assessment of a closed reduction in DDH, gadolinium-enhanced MRI provides information about femoral head perfusion that may be predictive for future AVN. At present, it is premature to use the perfusion information for routine clinical use. However, it opens the door to studies looking at repositioning or alternative reduction methods that may reduce the risk of AVN in this higher risk group.

Neuroimaging of the child with developmental delay.

Developmental delay (DD) affects approximately 1% to 3% of all children in the United States. This diagnosis significantly impedes quality of life and full participation in the life of the family, school, and community. In this setting, the clinicians ability to detect, diagnose, and possibly treat the cause for DD in a timely manner depends on a multimodality approach to neuroimaging and a robust understanding of the various imaging algorithms aimed at determining the etiology of disease, structural and/or anatomic defects, functional activity, metabolic profiles, and genetic characteristics. Taken separately and in combination, these features are effectively depicted and analyzed using an array of brain imaging modalities: ultrasound, computed tomography, nuclear medicine, magnetic resonance (MR) spectroscopy, and a growing mix of sophisticated MR imaging (MRI) techniques, including diffusion-weighted imaging, diffusion tensor imaging, perfusion MRI, and functional MRI. Thus, equipped with these advanced imaging capabilities, pediatric neurologists and neuroradiologists are now positioned to diagnose with greater accuracy and speed; this, in turn, results in more effective treatment plans and improved patient outcomes as measured by progress in reaching developmental milestones and in ameliorating secondary conditions such as seizures, poor motor control, incontinence, and impulsivity. The purpose of this article is to present the numerous causes of pediatric DD, describe their respective neuroimaging findings, discuss various neuroimaging approaches for elucidating etiology, and offer specific guidelines for optimizing imaging results in the setting of multimodality imaging capabilities.

Network analysis of UBE3A/E6AP-associated proteins provides connections to several distinct cellular processes

Perturbations in activity and dosage of the UBE3A ubiquitin-ligase have been linked to Angelman syndrome and autism spectrum disorders. UBE3A was initially identified as the cellular protein hijacked by the human papillomavirus E6 protein to mediate the ubiquitylation of p53, a function critical to the oncogenic potential of these viruses. Although a number of substrates have been identified, the normal cellular functions and pathways affected by UBE3A are largely unknown. Previously, we showed that UBE3A associates with HERC2, NEURL4, and MAPK6/ERK3 in a high-molecular-weight complex of unknown function that we refer to as the HUN complex (HERC2, UBE3A, and NEURL4). In this study, the combination of two complementary proteomic approaches with a rigorous network analysis revealed cellular functions and pathways in which UBE3A and the HUN complex are involved. In addition to finding new UBE3A-associated proteins, such as MCM6, SUGT1, EIF3C, and ASPP2, network analysis revealed that UBE3A-associated proteins are connected to several fundamental cellular processes including translation, DNA replication, intracellular trafficking, and centrosome regulation. Our analysis suggests that UBE3A could be involved in the control and/or integration of these cellular processes, in some cases as a component of the HUN complex, and also provides evidence for crosstalk between the HUN complex and CAMKII interaction networks. This study contributes to a deeper understanding of the cellular functions of UBE3A and its potential role in pathways that may be affected in Angelman syndrome, UBE3A-associated autism spectrum disorders, and human papillomavirus-associated cancers.