Biomedical subjects

Dale Swift

Publications and source records attributed to Dale Swift.

5 recordsLinked to original sources

PubMed2005

Robotically guided radiosurgery for children.

BACKGROUND: A robotically guided linear accelerator has recently been developed which provides frameless radiosurgery with high precision. Potential advantages for the pediatric population include the avoidance of the cognitive decline associated with whole brain radiotherapy, the ability to treat young children with thin skulls unsuitable for frame-based methods, and the possible avoidance of general anesthesia. We report our experience with this system (the "Cyberknife") in the treatment of 21 children. PROCEDURES: Cyberknife radiosurgery was performed on 38 occasions for 21 patients, age ranging from 8 months to 16 years (7.0 +/- 5.1 years), with tumors considered unresectable. Three had pilocytic astrocytomas, two had anaplastic astrocytomas, three had ependymomas (two anaplastic), four had medulloblastomas, three had atypical teratoid/rhabdoid tumors, three had craniopharyngiomas, and three had other pathologies. The mean target volume was 10.7 +/- 20 cm(3), mean marginal dose was 18.8 +/- 8.1 Gy, and mean follow-up is 18 +/- 11 months. Twenty-seven (71%) of the treatments were single-shot and eight (38%) patients did not require general anesthesia. RESULTS: Local control was achieved in the patients with pilocytic and anaplastic astrocytoma, three of the patients with medulloblastoma, and the three with craniopharyngioma, but not for those with ependymoma. Two of the patients with rhabdoid tumors are alive 16 and 35 months after this diagnosis. There have been no procedure related deaths or complications. CONCLUSION: Cyberknife radiosurgery can be used to achieve local control for some children with CNS tumors without the need for rigid head fixation.

Adolescent↗

PubMed2005

Neurocytoma-like neoplasm of the thoracic spine in a 15-month-old child presenting with diffuse leptomeningeal dissemination and communicating hydrocephalus. Case report.

This unusual mixed glioneuronal neoplasm of the spine resembling central neurocytoma is only the second reported example of a neoplasm of this type involving the spinal cord and is, seemingly, the first to present with diffuse leptomeningeal dissemination and communicating hydrocephalus. This 15-month-old boy presented with somnolence, bilateral sixth nerve palsy, and lower-extremity weakness and was found to harbor a primary neoplasm within the thoracic spine and associated syrinx, widespread leptomeningeal dissemination, and communicating hydrocephalus. The patient underwent cerebrospinal fluid shunt placement, thoracic laminectomy for tumor debulking and biopsy, chemotherapy, and radiation therapy to the neuraxis. Immunohistochemically, the tumor was marked by evidence of mixed glial (glial fibrillary acidic protein-positive) and neuronal (synaptophysin-positive) differentiation. Mitotic activity was inconspicuous. No areas of vascular proliferation, necrosis, or marked nuclear pleomorphism were noted. Mixed glioneuronal neoplasms are a heterogeneous group of tumors whose biological potential remains incompletely defined. The present case illustrates the reality that some of these neoplasms can be clinically aggressive, despite comparatively bland histological features. The authors' goal is to acquaint neurosurgeons with the expanding spectrum of mixed glioneuronal neoplasms and with the potential of some of these lesions to pursue an aggressive clinical course.

Arachnoid↗

PubMed2004

Advanced "tactile" medical imaging for separation surgeries of conjoined twins.

BACKGROUND: Understanding the anatomy of conjoined twins is difficult because of the rarity of this congenital malformation and the scarcity of reported cases in medical literature. NEW TECHNOLOGY: Advances in radiologic imaging, computer modeling, and sophisticated manufacturing techniques enable medical imaging datasets to be translated into accurate, solid, life-size models. These models, which can be designed to include various combinations of anatomical features revealed by established imaging modalities, are important for pre-surgical assessments and planning, as well as for reference during the actual operative procedure. In addition, they provide a valuable basis for communication between the groups of specialists who are involved in these cases. CASE STUDIES: This article will describe the advances in technology behind this process and illustrate its value in two cases of craniopagus twins.

Adult↗

PubMed2004

Performance and complications associated with the synchromed 10-ml infusion pump for intrathecal baclofen administration in children.

OBJECT: The objectives of this multicenter study were to monitor the performance of a 10-ml pump infusing intrathecal baclofen to treat 100 children with cerebral spasticity, to monitor complications associated with the pump, and to correlate pump-related complications with body habitus. METHODS: Age at implantation of the pump ranged from 1.4 to 16.8 years (mean 8.1 years). The effects of ITB on spasticity in the upper and lower extremities were evaluated using the Ashworth Scale. Data were collected regarding implant site, infection, complication, and body mass index (BMI). Ashworth Scale scores decreased significantly in the upper and lower extremities at 6 and 12 months after pump implantation (p < 0.001). There were four serious system-related complications, all specific to catheters. There were 32 serious procedure-related complications in 21 patients: 11 complications were infections that occurred in nine patients. Four of nine pump-induced infections were treated with pump removal and antibiotic therapy; five infections were treated successfully with antibiotic therapy alone, without pump removal. In children younger than 8 years of age there was a significantly higher incidence of serious procedure-related adverse events than in older children. There was no significant correlation between BMI and the incidence of pump pocket-related complications or infections. CONCLUSIONS: The 10-ml pump can be used therapeutically in small children, particularly those weighing less than 40 lbs, with greater ease and less wound tension, than the conventional 18-ml pump. The incidence of complications associated with the 10-ml pump in younger children appears to be similar to that previously reported with the 18-ml pump in larger-sized children.

Adolescent↗

PubMed2003

Long-term intrathecal baclofen therapy for severe spasticity of cerebral origin.

OBJECT: The goal of this study was to ascertain the long-term effectiveness and safety of intrathecal baclofen (ITB) in the treatment of spasticity of cerebral origin in children and young adults. METHODS: A prospective, multicenter study was conducted in 68 patients who had been enrolled in the initial evaluation of ITB therapy and were willing to participate in long-term surveillance. Seventy-three percent of the patients were younger than 16 years of age at the time of study entry. The patients were examined at least every 3 months and were observed for an average of 70 months. At each follow-up visit, spasticity in the upper and lower extremities was evaluated by applying Ashworth scores. All adverse events and complications were recorded on standardized data forms. Spasticity in both upper and lower extremities decreased significantly (p < 0.005) and remained decreased up to 10 years. The dosage of ITB increased from a mean of 157 microg/day 3 months after pump insertion to 300 microg/day at 2 years postimplantation, and remained relatively stable thereafter. There were no significant differences in ITB dosage in children of different ages. Adverse events potentially related to ITB therapy occurred in 50% of patients within 2 months after pump insertion and in 50% of patients thereafter; hypotonia and lethargy were the two most common adverse events. The most common complications of surgery were catheter-related problems (31%), seromas (24%), and cerebrospinal fluid leaks (15%). CONCLUSIONS: Intrathecal baclofen provides effective long-term treatment of spasticity of cerebral origin and its effects do not appear to diminish with time. This therapy is frequently associated with adverse side effects that usually can be alleviated by adjustments in dosage.

Adolescent↗