PubMed Health⌕ Search

Biomedical subjects

Paul Steinbok

Publications and source records attributed to Paul Steinbok.

At least 19 recordsLinked to original sources
PubMed2006

Simple technique of head fixation for image-guided neurosurgery in infants.

INTRODUCTION: The authors describe an extremely simple technique of head fixation for image-guided neurosurgery in young children in whom standard pin fixation cannot be used. MATERIALS AND METHODS: This involves positioning the head on a horseshoe headrest and using a 'U-drape' to fix the head to the headrest. RESULT: Over the last 5 years, this technique of head fixation (in conjunction with Stealthstation) has been used for various neurosurgical procedures in more than ten infants successfully.

Brain Diseases↗
PubMed2006

Selection of treatment modalities in children with spastic cerebral palsy.

The purpose of this report was to outline the various options currently used for treatment of spastic cerebral palsy (CP) and to discuss factors involved in selecting the appropriate treatment modalities for the individual child. In a review of the literature and his personal observations, the author presents an outline of treatment options and the criteria for using each. Therapeutic options include the following: physiotherapy; occupational therapy; oral spasmolytic and antidystonic drugs; botulinum toxin injections; orthopedic procedures; continuous infusion of intrathecal baclofen (ITB); selective dorsal rhizotomy (SDR); and selective peripheral neurotomy. The most commonly used neurosurgical procedures are ITB pump placement and SDR, and these are discussed in the most detail. The author's personal schema for assessment of the child to determine the nature of the hypertonia, the impact of the hypertonia, and the appropriate therapeutic intervention is presented. There are factors that help guide the optimal treatment modalities for the child with spastic CP. The treatment of these children is optimized in the setting of a multidisciplinary team.

Baclofen↗
PubMed2006

Tuberous sclerosis complex: a review of the management of epilepsy with emphasis on surgical aspects.

OBJECTIVE: To review the management of epilepsy in patients with tuberous sclerosis complex (TSC) with an emphasis on surgical aspects, neuropathology, and pathogenesis. METHODS: Review of the literature and presentation of the authors' experience of surgery for refractory epilepsy in patients with TSC. RESULTS: TSC is a multisystem genetic disorder with variable phenotypic expression. TSC results from a mutation in the TSC1 gene on chromosome 9, which codes for hamartin, or in the TSC 2 gene on chromosome 16 which codes for tuberin. The majority of the patients have TSC as a result of spontaneous genetic mutations while in one-third of the patients, the disorder is inherited in an autosomal dominant manner. Epilepsy is the most common neurological complication, and up to 80-90% of individuals with TSC develop epilepsy at some point in their lifetime. The onset of epilepsy is typically in early childhood. Infantile spasms are a very common early seizure type although partial seizures may occur. Developmental delay, intellectual impairment, autism, behavioral problems, and neuropsychiatric disorders occur commonly in individuals with TSC and may be associated with poorly controlled epilepsy. Antiepileptic drugs are the first-line management for epilepsy but the ketogenic diet, resection of one or more tubers, corpus callosotomy, and vagus nerve stimulation are other therapeutic options for individuals with poorly controlled epilepsy.

Cognition↗
PubMed2006

Spontaneous regression of cerebellar astrocytoma after subtotal resection.

CASE REPORT: The authors report a child in whom residual cerebellar astrocytoma after surgical resection was documented on serial computed tomography scans to undergo gradual complete regression spontaneously over a period of 11 years. In this case, the time course of regression has been well documented. CONCLUSION: The time course of regression may provide clues as to the underlying cause of this phenomenon.

Astrocytoma↗
PubMed2006

Etiological differences between the isolated lateral ventricle and the isolated fourth ventricle.

OBJECTIVE: To determine if an etiological difference exists between isolation of the lateral ventricle and isolation of the fourth ventricle after ventricular shunting. METHODS: Cases of symptomatic isolation of the lateral and fourth ventricles were reviewed retrospectively. The ages at presentation of ventricular isolation, the time course to development of isolation, the number of shunt surgeries leading up to symptomatic isolation, the types of shunt valves utilized, and the background of infection were analyzed. RESULTS: Twenty-six patients had lateral ventricle isolation and 11 patients had fourth ventricle isolation. Infection, hemorrhage, Chiari malformation/myelomeningocele, and aqueductal stenosis were factors contributing to hydrocephalus requiring treatment in these patients. Compared to 26.9% of patients with lateral ventricle isolation, 90.9% of patients with fourth ventricle isolation had a previous history of infection. CONCLUSIONS: Prior meningitis and ventriculitis frequently contributed to fourth ventricle isolation. Lateral ventricle isolation seems to arise from functional obstruction of the foramen of Monro related to prior shunting.

Adolescent↗
PubMed2006

Quantifying positional plagiocephaly: reliability and validity of anthropometric measurements.

The treatment of positional plagiocephaly is controversial. A confounding factor is the lack of a proven clinically viable measure to quantify severity and change in plagiocephaly. The use of anthropometric measurements is one proposed method. In this study, the reliability and validity for this method of measurement were investigated. Two clinicians independently recorded caliper measurements of cranial vault asymmetry (CVA) for infants referred for plagiocephaly or torticollis, and an unbiased observer recorded visual analysis scores during the same visit. CVA scores were assigned into three predetermined severity categories (normal CVA < 3 mm, mild/moderate CVA 12 mm). CVA measurements and visual analysis scores were recorded for 71 and 54 infants, respectively. Intrarater reliability was established (kappa = 0.98, kappa = 0.99), but inter-rater reliability was not (kappa = 0.42). In addition, the inter-rater reliability for the severity categories based upon these measures was poor (kappa = 0.28) and failed to correlate to the visual analysis (kappa = 0.31). Development of a stable and meaningful measurement system for the extent of plagiocephaly is needed to allow scientific studies of the natural history of plagiocephaly and effectiveness of interventions.

Age Factors↗
PubMed2006

Pseudoclosure of anterior fontanelle by wormian bone in isolated sagittal craniosynostosis.

AIMS AND OBJECTIVES: Although syndromic craniosynostosis is one of the causes for early closure of the anterior fontanelle, there is no literature on the incidence and causes of fontanelle closure in isolated single-suture craniosynostosis. The objective of this study was to review the incidence of fontanelle closure by a wormian bone in isolated, nonsyndromic sagittal craniosynostosis. MATERIALS AND METHODS: Intraoperative records of 100 consecutive children under 1 year of age, operated for isolated sagittal synostosis over a 14-year period (1987- 2000), were reviewed to identify the presence of a wormian bone closing the anterior fontanelle. RESULTS: The median age at surgery was 4.2 months with a range of 1.9-11.7 months. Intraoperatively, a wormian bone was seen replacing the anterior fontanelle in 4 cases giving an incidence of 4%. CONCLUSIONS: A wormian bone can occupy the anterior fontanelle in children with isolated sagittal craniosynostosis giving the appearance of a 'closed fontanelle'.

Cranial Fossa, Anterior↗
PubMed2006

Occult tethered cord syndrome: a survey of practice patterns.

OBJECT: Tethered cord syndrome (TCS) is associated with a number of congenital anomalies involving early development of the spinal cord. These include myelomeningocele, spinal cord lipoma, low-lying conus medullaris, and a fibrofatty terminal filum. Occult TCS occurs in patients when clinical features indicate a TCS but the typical anatomical abnormalities are lacking. It is controversial whether surgical release of the terminal filum leads to clinical improvement in a patient who does not have a previously identified anatomical abnormality. To assess the clinical standard used by practicing pediatric neurosurgeons, a practice survey was conducted at the 2004 Annual Meeting of the Joint Section for Pediatric Neurological Surgery of the American Association of Neurological Surgeons/Congress of Neurological Surgeons. METHODS: The survey examined clinical decision making for a same-case scenario with differing appearance on imaging studies. There was a clear consensus regarding diagnosis and treatment in the patient with symptoms, a low-lying conus medullaris, and a fatty terminal filum. The vast majority of respondents (85%) favored surgical untethering for this patient. A majority of respondents (67%) also favored treatment for the patient having symptoms and a fatty terminal filum. There was, however, significant disagreement regarding the diagnosis and treatment of disease in one patient with symptoms and an inconclusive magnetic resonance imaging study. Some respondents clearly favored surgery, whereas others believed that this patient did not meet the diagnostic criteria for TCS. CONCLUSIONS: The results of this survey support the development of a randomized clinical trial to address the benefit of surgery for occult TCS.

Cauda Equina↗
PubMed2006

Reformation of the sagittal suture following surgery for isolated sagittal craniosynostosis.

OBJECT: Data from animal studies have shown that in experimentally induced craniosynostosis, removal of the involved calvaria results in the formation of new calvaria with time, and sutures redevelop in their normal anatomical positions. However, the pattern of suture reformation following surgery in humans with craniosynostosis remains ill-defined. The aim of this study was to determine the pattern of postoperative suture reformation in children who have undergone surgery for isolated sagittal synostosis and assess possible factors related to suture reformation. METHODS: Records were retrospectively reviewed for 42 consecutive infants who had surgery for isolated sagittal synostosis between 1987 and 2000 and for whom postoperative skull radiographs were available. The radiographs were evaluated for sagittal suture morphology and patency of the coronal and lambdoid sutures. Surgery involved at a minimum 1) a vertex craniectomy, characterized by removal of the sagittal suture and a 1.5- to 2.5-cm piece of adjacent parietal bone with the attached pericranium bilaterally, and 2) parietal osteotomies and/or craniectomies. The median age at surgery was 3.9 months (range 1.9-7.6 months). The mean duration of follow up was 32.2 months (range 6-144 months). The sagittal suture had reformed in only seven (16.7%) of the children at follow up. In the other 35 (83.3%), the craniectomized bone defects had reossified without any part of the sagittal suture being visible on the radiographs. CONCLUSIONS: There is a very low incidence of suture reformation in children after surgery for isolated sagittal craniosynostosis. Genetic predisposition, inclusion of undiagnosed syndromic patients, and current operative techniques may be some of the factors responsible for the low incidence of suture reformation seen in this series.

Cranial Sutures↗
PubMed2005

Phase II study of high-dose chemotherapy before radiation in children with newly diagnosed high-grade astrocytoma: final analysis of Children's Cancer Group Study 9933.

BACKGROUND: High-grade astrocytomas (HGA) carry a dismal prognosis and compose nearly 20% of all childhood brain tumors. The role of high-dose chemotherapy (HDCT) in the treatment of HGA remains unclear. METHODS: In a nationwide study, The Children's Cancer Group (CCG) prospectively evaluated 102 children with HGA and postoperative residual disease for efficacy and toxicity of four courses of HDCT before radiotherapy (RT). Patients were randomly assigned to one of three couplets of drugs: carboplatin/etoposide (Regimen A), ifosfamide/etoposide (Regimen B), or cyclophosphamide/etoposide (Regimen C). After HDCT, all patients were to receive local RT followed by lomustine and vincristine. Twenty-six patients were excluded after central neuroradiographic review (n = 8) or pathology review (n = 18). RESULTS: Of 76 evaluable patients (median age, 11.95 yrs; range, 3-20 yrs), 30 patients relapsed during HDCT, and 11 others did not complete HDCT because of toxicity. Nonhematologic serious toxicities were common (29%), and 21% of patients did not receive RT. Objective response rates were not associated with amount of residual disease and did not statistically differ between regimens: 27% (Regimen A), 8% (Regimen B), and 29% (Regimen C). Overall survival (OS) was 24% +/- 5% at 5 years and did not differ between groups. Median time to an event was longest for Regimen A (283 days compared with 83 and 91 days for Regimens B and C, respectively). The five-year, event-free survival (EFS) rate for all patients was 8% +/- 3% and 14% +/- 7% for Regimen A (P = 0.07). CONCLUSIONS: OS and EFS were not affected by histologic grade. Patients who responded to HDCT had a nominally higher survival rate (P = 0.03 for trend). The authors conclude that these commonly used HDCT regimens provide no additional clinical benefit to conventional treatment in HGA, regardless of the amount of measurable residual tumor.

Adolescent↗
PubMed2005

Diagnosis of isolated sagittal synostosis: are radiographic studies necessary?

AIMS AND OBJECTIVES: Isolated sagittal synostosis can be diagnosed easily on clinical grounds. This study was designed to determine if children could be operated on based solely on a clinical diagnosis or whether such an approach would result in any potentially unnecessary surgeries. MATERIALS AND METHODS: Records of 114 consecutive children operated on for isolated nonsyndromic sagittal synostosis over a 14-year period (1987-2000) were reviewed to see whether the clinical findings were in concordance with the intraoperative findings and histopathology of the sagittal suture. RESULTS: The age at surgery ranged from 1.9 to 81.3 months (median 4.3 months). Preoperative skull radiographs were done in 78 children and computer tomography (CT) scans of the head in 12 children. One hundred percent of the skull radiographs and 83.3% of the CT scans were completed prior to referring the children to a pediatric neurosurgeon. CT scans confirmed the diagnosis in all patients in whom it was available. For the rest, pathology reports and/or operative records were available for 108 (94.7%) children and were confirmatory for sagittal craniosynostosis in all. CONCLUSIONS: Accurate diagnosis of isolated sagittal synostosis can be made clinically, and operative correction can proceed without a need for radiological investigations, unless the clinical features are not completely typical. This approach could result in significantly reduced radiation exposure for the developing brain and could provide economic benefits to health care providers.

Child↗
PubMed2005

Childhood craniopharyngioma: Vancouver experience.

OBJECTIVE: To present our institution's experience in the management of childhood craniopharyngioma since 1982. METHODS: We retrospectively reviewed the records of all children diagnosed with craniopharyngioma at our children's hospital from its opening in 1982 through to 2003. One neuroradiologist systematically reviewed the neuroimaging. Kaplan-Meier curves were used to analyze the progression-free survival and the overall survival from the time of the first definitive intervention. CONCLUSIONS: Most children diagnosed with craniopharyngioma are long-term survivors. Survivors suffer from multiple deficits in the long term. A conservative surgical and radiotherapeutic approach and avoiding interventions that are known to cause severe morbidity may minimize these. The use of intracystic bleomycin is a strategy that allows the delay of more aggressive therapies in select patients.

Adolescent↗
PubMed2005

Predictors of poor outcome after selective dorsal rhizotomy in treatment of spastic cerebral palsy.

OBJECTIVES: The purpose of the study was to determine if there are preoperative clinical characteristics that might be predictive of a poor outcome after selective dorsal rhizotomy (SDR) surgery in children with spastic cerebral palsy (CP). METHODS: A retrospective analysis was performed on 174 children who had undergone SDR from 1983 to 2001. Patients were divided into two groups according to their outcome at approximately 1 year after surgery: "acceptable" or "poor" outcome. As predictors of outcome, the factors compared were age at operation, types of CP (diplegia, quadriplegia), history of prematurity, prior lower limb orthopedic surgeries, history of seizures, dystonic limbs, opisthotonic posturing, lumbar hyperlordosis, truncal hypotonia, preoperative ambulatory function, preoperative Gross Motor Function Classification System (GMFCS) scores, and presence of intellectual delay and speech delay. RESULTS: Eleven children (6.3%) had a "poor" outcome. The type of CP (P<0.001) and intellectual delay (P=0.015) were significant predictors of outcome in the univariate regression analysis, but only the type of CP retained significant predictive power in the multivariate analysis. CONCLUSION: These data suggest that preoperative diagnosis is the strongest predictor of outcome after SDR. Intellectual delay demonstrated predictive power only in the univariate model, suggesting that it might have some prognostic value but less than the diagnosis.

Adolescent↗
PubMed2005

Spinal deformities after selective dorsal rhizotomy for spastic cerebral palsy.

OBJECT: Spinal deformities are significant problems in children with spastic cerebral palsy. The treatment of their spasticity by selective dorsal rhizotomy (SDR) may worsen or improve these problems. The purpose of this study was to determine the incidence of and change in degree of thoracolumbar scoliosis, thoracic kyphosis, and lumbar lordosis in children who have undergone SDR. METHODS: A retrospective review was conducted of children younger than 18 years of age, who had undergone SDR at British Columbia's Children's Hospital from 1987 to 2001 and in whom preoperative and postoperative spine radiographs have been obtained. Angles for thoracolumbar scoliosis, thoracic kyphosis, and lumbar lordosis were measured. The study group comprised 105 patients. The mean age at surgery was 5.2 years (range 2.7-14.6 years), with a mean time to most recent follow-up radiographs of 4.3 years (1-13.6 years). Sixty-two children had spastic diplegia (59%), 34 spastic quadriplegia (32%), and nine quadriplegia and intellectual delay (9%). A total of 104 children underwent laminoplasty with replacement of the laminae, usually from L-1 to S-1 and 54.8% of children had scoliosis at last follow up, with 25% having worsening of 10 degrees or more. The incidence of abnormal kyphosis at the last follow-up visit was 38.6%, with 31.8% having worsening of 15 degrees or more. The incidence of hyperlordosis at last follow up was 21.3%, with 36% having worsening of 15 degrees or more. The factors in this series impacting development of spinal deformities have been analyzed and are discussed. CONCLUSIONS: The relatively high incidence of spinal deformity in children who have undergone SDR via multi-level lumbosacral laminoplasties should raise some concern.

Adolescent↗