Complex Pediatric Elbow Injury: An Uncommon Case

Background  

There is paucity of literature describing complex elbow trauma in the pediatric population. We described a case of an uncommon pediatric elbow injury comprised of lateral condyle fracture associated with posterolateral dislocation of elbow.     

Digit representation is more than just hand waving

Lip-reading and interpreting hand gestures help provide nonverbal information that aids speech comprehension in noisy environments and places emphasis on certain key utterances. In this fMRI study, we examined if viewing the similar semantic information presented by either finger movements or lip movements was processed by common or discrete brain regions. Subjects viewed videos of a hand conveying number information via finger movements and a face whose lip movements conveyed the same numerical information. Control stimuli consisted of meaningless finger and lip movements. Lip-reading numbers activated left posterior superior temporal sulcus (STS), while identifying numbers presented by fingers activated the intraparietal region (IPR) bilaterally. Conjunction analysis highlighted common activation in right IPR to numbers presented via fingers and lips. Our data indicate that left hemisphere decodes human movements conveying semantic information, although the specific brain region that is engaged may depend on the body part that is moving.     

Automatic MR volume registration and its evaluation for the pelvis and prostate

A three-dimensional (3D) mutual information registration method was created and used to register MRI volumes of the pelvis and prostate. It had special features to improve robustness. First, it used a multi-resolution approach and performed registration from low to high resolution. Second, it used two similarity measures, correlation coefficient at lower resolutions and mutual information at full resolution, because of their particular advantages. Third, we created a method to avoid local minima by restarting the registration with randomly perturbed parameters. The criterion for restarting was a correlation coefficient below an empirically determined threshold. Experiments determined the accuracy of registration under conditions found in potential applications in prostate cancer diagnosis, staging, treatment and interventional MRI (iMRI) guided therapies. Images were acquired in the diagnostic (supine) and treatment position (supine with legs raised). Images were also acquired as a function of bladder filling and the time interval between imaging sessions. Overall studies on three patients and three healthy volunteers, when both volumes in a pair were obtained in the diagnostic position under comparable conditions, bony landmarks and prostate 3D centroids were aligned within 1.6 +/- 0.2 mm and 1.4 +/- 0.2 mm, respectively, values only slightly larger than a voxel. Analysis suggests that actual errors are smaller because of the uncertainty in landmark localization and prostate segmentation. Between the diagnostic and treatment positions, bony landmarks continued to register well, but prostate centroids moved towards the posterior 2.8-3.4 mm. Manual cropping to remove voxels in the legs was necessary to register these images. In conclusion, automatic, rigid body registration is probably sufficiently accurate for many applications in prostate cancer. For potential iMRI-guided treatments, the small prostate displacement between the diagnostic and treatment positions can probably be avoided by acquiring volumes in similar positions and by reducing bladder and rectal volumes.     

Human neural responses elicited to observing the actions of others

Monkey electrophysiological and human neuroimaging studies indicate the existence of specialized neural systems for the perception and execution of actions. To date, the dynamics of these neural systems in humans have not been well studied. Here, we investigated the spatial and temporal behavior of human neural responses elicited to viewing motion of the face, hand, and body. Scalp event-related potentials (ERPs) were recorded in 20 participants viewing videotaped mouth (opening, closing), hand (closing, opening), and body stepping (forward, backward) movements. ERP peak differences within the movements of each body part were compared using topographical maps of voltage, voltage difference, and Student's t-test at ERP peak latencies. Predominantly temporoparietal negative ERPs occurred to motion of all body parts within 200 ms postmovement onset. Hand closure elicited a significantly greater negativity than opening, particularly in the left hemisphere. Vertex positive ERPs within 300 ms postmovement onset were elicited to hand and body motion. A significantly greater positivity occurred for the body stepping forward relative to stepping backward. The ERP topography was consistent with observed activation foci in human neuroimaging studies. Our data indicate that the neural activity of a system dedicated to the perception of high-level motion stimuli can rapidly differentiate between movements across and within body parts.     

Visual function in breast-fed term infants weaned to formula with or without long-chain polyunsaturates at 4 to 6 months: a randomized clinical trial

OBJECTIVE: Breast-fed infants receive docosahexaenoic acid (DHA) and arachidonic acid (ARA) in their diet. Upon weaning, infants lose this dietary source of long-chain polyunsaturates because many commercial formulas do not contain these important constituents for neural membrane biogenesis. We evaluated the benefits of postweaning dietary supplementation of DHA + ARA on visual maturation. STUDY DESIGN: Healthy term infants (n = 61) were breast-fed to 4 to 6 months, then were randomly assigned to commercial formula or formula supplemented with DHA (0.36%) + ARA (0.72%). Measurements of red blood cell (RBC) fatty acids, visually evoked potential (VEP) acuity, and stereoacuity were done before and after weaning. RESULTS: At 1 year of age, RBC-DHA in the commercial formula-fed group was reduced by 50% from the weaning level, whereas there was a 24% increase in the DHA + ARA-supplemented group. The primary outcome measure, VEP acuity, was significantly more mature in supplemented infants at 1 year of age. Elevated RBC-DHA levels were associated with more mature VEP acuity. There were no significant diet-related differences in stereoacuity. CONCLUSIONS: These data extend through the first year of life the critical period in which a dietary supply of DHA and ARA can contribute in optimizing visual development in term infants.     

Respiratory syncytial virus infection and immunoprophylaxis for selected high-risk children in Central Australia

BACKGROUND: There are limited data on the epidemiology and viral aetiology of bronchiolitis in Central Australia and respiratory syncytial virus (RSV) immunoprophylaxis in an Australian population. OBJECTIVE: To (i) determine the incidence and the viral aetiology of bronchiolitis hospitalisations and (ii) report on the usage of RSV immunoprophylaxis in selected high-risk infants and children in Central Australia. METHODOLOGY: A retrospective review was performed of all hospital separations for bronchiolitis for a three-year period, 1998-2000. Respiratory viruses in the nasopharyngeal aspirates were identified from the cases in the year 2000. A combined retrospective chart review and prospective follow up study was undertaken of all the infants and children who received RSV immunoprophylaxis at the Alice Springs Hospital, Central Australia. RESULTS: Incidence of bronchiolitis hospitalisation in infants for 1998, 1999 and 2000 were 176, 200 and 180 per 1000, respectively. Nine high-risk children had RSV immunoprophylaxis on a total of 46 occasions and there were two mild RSV-related illnesses in them. None had severe lower respiratory tract illness. CONCLUSION: The incidence of bronchiolitis in Central Australia is extremely high. The usage of RSV immunoprophylaxis may be justified in selected high-risk children living in high endemic areas.     

Interventional radiology in the spleen

Despite the widespread use of interventional radiologic techniques, there has been reluctance to apply these to the spleen. Concern for bleeding and difficulty in negotiating around the colon and pleura have limited its use. The authors report their experience with interventional radiology of the spleen in 35 cases, including percutaneous biopsy (n = 5), diagnostic and therapeutic fluid aspiration (n = 14), and catheter drainage of abscesses (n = 9), hematomas (n = 2), intrasplenic pancreatic pseudocysts (n = 2), and necrotic tumor (n = 1). Transsplenic fluid aspiration and biopsy of the pancreas and adrenal gland were performed as well (n = 2). All procedures were performed under computed tomographic or ultrasound guidance. Biopsies were performed with 22- or 20-gauge needles only; no complications were encountered. Diagnoses included primary and secondary malignancies and an infectious process. Drainages were successful in 11 of 14 patients; pleural effusions occurred in two cases, but neither required specific therapy. Interventional radiologic procedures in the spleen are feasible, and the authors discuss methods to promote their safe application.