Search

Lipoblastomatous lesions are mesenchymal tumors of embryonal white fat and are classified into two forms: a superficial, well-defined mass (lipoblastoma) or a deep, infiltrative lesion (lipoblastomatosis). We report an unique case of mediastinal lipoblastoma in a 17-month-old boy which harbored a dual nature and exhibited the characteristics of both forms, a large well-encapsulated intrathoracic main tumor with focal infiltrative features at the thoracic inlet and transforaminal intraspinal extension forming a long-segment extradural mass. In addition to specific signal characterization of a fatty mediastinal mass with intratumoral streaks and whorls corresponding to the fibrovascular network, magnetic resonance (MR) imaging offered clear demonstration of the chest wall, lower neck and intraspinal extension, which was important for preoperative planning.

Sharp penetrating trauma to the skull and brain is uncommon in children. The related pediatric literature consists mainly of cases involving penetrating stab wounds to the face or scalp resulting from assaults or accidents. Herein, we present two cases of perioral intracranial penetration. The first case was a 2-year-old boy who presented with septic complications and developed a brain abscess. The second case was a 2-year-old girl who presented with a subarachnoid hemorrhage and developed a traumatic pericallosal artery aneurysm. After craniotomy and clipping, both patients made a satisfactory recovery. A high index of suspicion, liberal use of neuroimaging and early operative intervention are important points in the successful management of such cases.

✓ The authors report the case of a 3-year-old boy who suffered from quadriparesis and respiratory distress after failing to execute a somersault properly. Neuroimaging revealed spinal cord contusion with marked spinal canal stenosis at the level of the atlas. No subtle instability, occult fracture, or other congenital abnormalities were confirmed. Spinal cord contusion with marked canal stenosis is rare, and only several adult cases have been reported. Severe stenosis at the level of the atlas may predispose individuals to severe spinal cord contusion, as occurred in our patient after sustaining trivial trauma.

This retrospective chart review describes the clinical features, pathogens, and outcomes of 46 patients with cerebrospinal fluid (CSF) shunt infections collected over 16 years. The overall CSF shunt infection rate was 2.1%, broken down into 1.7 and 9.3% in adult and pediatric groups, respectively. Fever and progressive consciousness disturbance were the most clinical features in the adult patient group, whereas disturbance of consciousness and abdominal symptoms and signs were the two most common clinical features in the pediatric patient group. The most frequently isolated microorganisms were of the Staphylococcus spp., including Staphylococcus aureus and coagulase negative Staphylococcus, which accounted for 47% of the episodes. Furthermore, increases in polymicrobial and Gram-negative bacilli infections were observed in our study. Due to the high proportion of oxacillin-resistant Staphylococcus spp. and polymicrobial infections, we recommend initial empirical antibiotics with both vancomycin and a third-generation cephalosporin for cases in which the causative bacteria has not been identified or for which the results of antimicrobial susceptibility tests are not available. For patients who develop smoldering fevers, progressive disturbed consciousness, seizures, or abdominal fullness after ventriculoperitoneal shunt procedures, CSF shunt infections should be suspected. Although some infections have been managed successfully with antimicrobial therapy alone, the timely use of appropriate antibiotics according to antimicrobial susceptibility testing and the removal of the shunt apparatus are essential for successful treatment.

Primary palmar hyperhidrosis often starts in childhood. It usually causes academic and social disabling at the age children begin primary school. This study included 65 children (44 girls and 21 boys, mean age 13.5 years) who underwent one-stage bilateral transthoracic endoscopic sympathectomy. The proper sympathetic segment was visualized in almost all cases and electrocautery ablation was performed. The immediate postoperative course was uneventful in all cases and no major morbidity was encountered. Horner's syndrome did not occur in any case. All patients were discharged the day of surgery or after an overnight stay. The duration of follow-up was from 6 months to 3 years. Although compensatory sweating was found in 40% of the patients, long-term satisfaction was reported in 63 cases (96%). This procedure is effective, simple, and is recommended as the method of choice for surgical treatment of severe upper extremity hyperhidrosis in children.

An analytical procedure is presented for the calculation of the statistical properties of the response of a linear elastic tall building under earthquake excitations. The emphasis is placed on the effect of the vertical ground motion. The restoring force in each story of the structural model is assumed to arise from the bending deformation of the columns whose rigidities are subject to a general reduction due to gravitational forces and to a random variation due to vertical ground accelerations. To illustrate the application of the procedure, numerical results are presented for a 6-story building. Within the limit of linear elastic deformation, the vertical ground acceleration is shown to be capable of causing an increase in certain response variables in the order of 10% for this moderately tall building. The percentage is expected to be larger for a taller building and much larger when the deformations exceed the elastic limit.

Using a simple structural model which consists of a massless column supporting a concentrated mass at the top, it is shown that the vertical ground motion in an earthquake can amplify the power of the horizontal ground motion, and cause greater horizontal structural displacement response. Furthermore, this amplification effect is greater for greater initial response; i.e., the response initally computed without taking the vertical excitation into consideration. Although the present analysis is based on a linear structural model, numerical computations have included large deflections so that the general trend can become more visible, and the results so obtained can provide useful guides for future investigation into the nonlinear inelastic regimes.

An analytical method is developed to calculate the statistical properties of the response of hysteretic columns under earthquake excitations, with special emphasis on the effect of the vertical ground acceleration. Both the vertical and horizontal ground accelerations are modeled as amplitude-modulated Gaussian random processes, and the restoring force in a column is assumed to follow a functional relationship proposed by Hata and Shibata. Numerical results are presented for two columns, having two contrasting values of the post-yielding to pre-yielding stiffness ratio of 0.5 and 0.1, respectively. These results indicate that the vertical ground acceleration has an aggravating effect similar to that of the gravitational force in causing greater peak mean-square structural response than one induced by the horizontal ground acceleration alone. The time variation of the mean-square response is found to be extremely sensitive to structural parameters. For softer structures with a small post-yielding to pre-yielding stiffness ratio, large permanent deformations may remain after termination of the earthquake excitations.