Search PubMed⌕ Search

Biomedical subjects

Paul Steinbok

Publications and source records attributed to Paul Steinbok.

At least 37 records · Page 2Linked to original sources
PubMed2005

Hip joint subluxation after selective dorsal rhizotomy for spastic cerebral palsy.

OBJECT: The effects of selective dorsal rhizotomy (SDR) procedures on the hip joints of children with spastic cerebral palsy (CP) are not well described. This study was performed to determine the incidence of hip subluxation in children with CP who underwent SDR at a single institution. METHODS: The study group comprised 82 patients (164 hip joints) with a mean follow up of 3.9 years. Forty-four patients had spastic diplegia (53.6%), 35 had spastic quadriplegia (42.7%), two had spastic triplegia (2.4%), and one had spastic hemiplegia (1.2%). The mean patient age at SDR was 5.2 +/- 2.4 years. Preoperative and postoperative hip radiographs were reviewed and the femoral head center edge (CE) angles were recorded. The mean pre- and postoperative right CE angles were 14.1 and 17.2 degrees, respectively, and those of the left were 13.6 and 15.1 degrees, respectively. Considering a change in CE angle greater than 5 degrees as clinically significant, 72 hips (43.5%) remained unchanged, 63 (38.4%) improved, and 29 (17.7%) worsened. Of a number of preoperative variables, including age at time of surgery, Gross Motor Function Classification System (GMFCS) level, ambulatory status, extent of hip subluxation, preoperative scoliosis, and asymmetry of hip subluxation, only GMFCS level was associated with worsening of hip subluxation. CONCLUSIONS: Selective dorsal rhizotomy is more likely to have a positive effect or no effect on hip joint subluxation rather than to have a negative effect. More severe involvement, as measured using the GMFCS, may predispose to worsening of hip subluxation after SDR.

Adolescent↗
PubMed2004

Minimizing blood transfusions in the surgical correction of coronal and metopic craniosynostosis.

OBJECTIVE: The current study was performed to determine the rate of allogeneic blood transfusion for coronal and metopic craniosynostosis surgery done by two experienced pediatric neurosurgeons and to identify factors associated with a need for transfusion. METHODS: First operations for coronal and metopic craniosynostosis correction in children from 1996 to 2002 were reviewed retrospectively. For analysis, the primary endpoint was defined as either the receipt of a blood transfusion or a postoperative Hb level below 70 g/l, even if no blood was transfused. Univariate and multivariate analyses were done to examine the relationship of attaining the primary endpoint to extent of surgery, surgeons, surgery time, preoperative hemoglobin, craniosynostosis type, weight, and age. RESULTS: Thirty-two patients were operated on: 17 with unicoronal; 9 with bicoronal, and 6 with metopic craniosynostosis. Median age at operation was 7.5 months. Blood transfusion rates were 0% for unicoronal, 44% for bicoronal, and 33% for metopic synostosis operations. Logistic regression revealed that the best predictor of having a postoperative hemoglobin level of <70 g/l or receiving a blood transfusion was the extent of surgery (beta=1.59, SE(beta)=0.57). The odds of reaching the primary endpoint for extensive surgery over basic surgery was 4.9 [95%CI=(1.6,15.0)]. Once extent of surgery was accounted for in the model, no other covariates significantly improved the model. CONCLUSIONS: Low transfusion rates were achieved in primary operations for coronal and metopic craniosynostosis using simple intraoperative techniques and by accepting a low postoperative hemoglobin level.

Analysis of Variance↗
PubMed2004

Clinical features of Chiari I malformations.

BACKGROUND: With the advent of MRI, the diagnosis of Chiari I malformation is being made in younger patients, often with minimal or no neurologic symptoms. CLINICAL FEATURES: The symptoms and signs of a Chiari I malformation may be related to the compression of neural and/or dural structures at the cranio-cervical junction or may be related to the associated syringomyelia. Scoliosis is a particularly important and common finding in those children with syringomyelia.

Arnold-Chiari Malformation↗
PubMed2004

International survey on the management of Chiari I malformation and syringomyelia.

INTRODUCTION: The availability of magnetic resonance imaging (MRI) has resulted in an increasing number of asymptomatic, minimally symptomatic, and doubtfully symptomatic patients being diagnosed with a Chiari I malformation with or without syringomyelia. In an attempt to clarify how neurosurgeons manage these clinical problems, an international survey on the Chiari I malformation and related syringomyelia was undertaken. METHOD: A questionnaire on the expected natural course of the disease and on aspects of the surgical technique for a number of hypothetical cases relating to Chiari I malformation with and without syringomyelia was used to survey Pediatric Neurosurgeons worldwide. RESULTS: Of 246 questionnaires distributed, 76 (30.8%) were completed and returned. There was a consensus that no operation should be carried out in asymptomatic patients with a Chiari I malformation, unless there is associated syringomyelia. There was a consensus that decompression of the Chiari malformation should be performed in patients with scoliosis when syringomyelia is present, and the majority decompressed the Chiari malformation in scoliotic patients even in the absence of syringomyelia. Suboccipital decompression was the standard surgical procedure for Chiari I malformations. The majority of respondents favored routine dural opening at surgery and closure with a pericranial or synthetic patch graft. In the case of a persistent or progressive syrinx after suboccipital decompression, the majority recommended shunting of the syrinx to the subarachnoid space or to the pleural cavity. CONCLUSION: There continues to be much variation in the management of the Chiari I malformation.

Arnold-Chiari Malformation↗
PubMed2004

Spontaneous hemorrhage into spinal neurenteric cyst.

CASE REPORT: A case of spontaneous hemorrhage into an intradural extramedullary neurenteric cyst at the C4-C6 level in a 6-year-old boy is reported. The child presented with sudden neck pain, torticollis, and myelopathy. The cyst was of high signal intensity on both T1- and T2-weighted magnetic resonance images, suggesting hemorrhage into the cyst. The combination of CT and MR provided useful preoperative information regarding the nature and the location of the cyst. A posterior approach via osteoplastic laminotomy was used for this anteriorly localized cyst. The use of intraoperative ultrasound was helpful in identifying and puncturing the cyst to minimize the spinal cord manipulation during the excision of the cyst wall. DISCUSSION: We report the first documented case of hemorrhage into a spinal neurenteric cyst that has been confirmed surgically and histopathologically.

Child↗
PubMed2004

Predicting stroke risk in pediatric moyamoya disease with xenon-enhanced computed tomography.

OBJECTIVE: To determine whether estimates of regional cerebral blood flow (rCBF) using xenon computed tomography (XeCT) in children with moyamoya disease can predict stroke risk before and after treatment. METHOD: Seven patients with moyamoya disease underwent 22 serial Xe computed tomographic scans. Estimates of rCBF were obtained at three computed tomographic levels by use of a 5-minute inhalation of 28% Xe. Acetazolamide challenge was performed in eight scans. For comparison of abnormal vessel distribution and areas of infarction, 17 intra-arterial digital subtraction angiograms, 47 computed tomographic scans, and 15 magnetic resonance imaging scans were available. Follow-up exceeded 36 months in all patients. Mean follow-up for the interventional group was 65.2 months (n = 5; range, 37-109 mo) and 38 months for the nonoperative patients (n = 2; 36 and 40 mo). RESULTS: Of six Xe computed tomographic scans obtained at diagnosis, four revealed regions of oligemia, augmented vertebrobasilar flow, and regions of carotid steal after acetazolamide. In the delay between diagnosis and treatment, three patients had strokes in ischemic areas identified by XeCT. Of the 10 posttreatment scans obtained from 4 patients, 2 revealed improved tissue perfusion with angiography confirming successful encephaloduroangiomyosynangiosis. In 2 others, XeCT performed 6 months posttreatment revealed improved perfusion without angiographic change, and angiography at 1 year revealed failed encephaloduroangiomyosynangiosis and new native collaterals. None of the patients with improved rCBF had new strokes. Eleven of 14 Xe computed tomographic scans were obtained within 30 days of angiography. Comparison of these studies demonstrates that regions of oligemia were confined to areas associated with vessel stenosis and little neovascularity or collateral pathways. CONCLUSION: XeCT, particularly with acetazolamide challenge, objectively quantifies rCBF. Our preliminary data suggest that it may permit assessment of stroke risk in children with moyamoya disease and may predict surgical outcome earlier than angiography.

Administration, Inhalation↗
PubMed2003

Reexamining the effects of epilepsy surgery on IQ in children: use of regression-based change scores.

Prior studies have found no adverse effects of pediatric epilepsy surgery on IQ. However, empirical techniques such as regression models, designed to account for confounding factors such as practice effects and test-retest reliability and able to provide a standardized method for evaluating outcome, have not been used in studying change after pediatric epilepsy. The goal of this study was to demonstrate the regression technique while empirically measuring the effect of epilepsy surgery on IQ in a group of pediatric patients. Predictors of retest IQ (e.g., baseline IQ, retest interval, demographics, epilepsy severity) were evaluated in a control group with intractable seizures (N = 23) assessed twice with the WISC-III. The resulting equation was used to evaluate IQ changes in a second group of children who underwent epilepsy surgery (N = 22). In controls, baseline IQ was a strong predictor of retest IQ. Number of AEDs was inversely related to retest IQ. Based on the control regression, four children (18%) in the surgical sample obtained significantly higher than expected postsurgical IQ scores and one child (5%) obtained a lower than expected IQ score. This study demonstrates that regression-based techniques yield informative estimates on outcome and may be an improvement over prior methods of measuring change after pediatric epilepsy surgery.

Adolescent↗
PubMed2003

Spontaneous resolution of calvarial eosinophilic granuloma in children.

OBJECTIVE: The recommended treatment for solitary calvarial eosinophilic granuloma (EG) is surgical resection by curettage, craniectomy or craniotomy. The purpose of this study was to describe the spontaneous resolution of calvarial EG and discuss 'observation only' as an option in the management of this condition. METHODS: A retrospective review was performed of children with calvarial EG seen at a tertiary care children's hospital. Of a total of 17 such patients, four were managed without any intervention and formed the basis of this report. RESULTS: In all four patients treated by 'observation only', there was a tender calvarial mass which enlarged rapidly over a few days and then resolved slowly over many weeks. The diagnosis of EG was based on the findings of plain radiographs and/or computed tomography. All masses had resolved by 8 weeks, and the underlying cranial defect filled in spontaneously in all cases. There was no recurrence at follow-up, which ranged from 2 months to 7 years. CONCLUSIONS: 'Observation only' should be considered as a viable option in the management of children with solitary calvarial masses that have the radiographic features of EG. Consideration should be given to delaying surgical intervention to allow time to see if spontaneous resolution occurs.

Adolescent↗
PubMed2003

Mutism after posterior fossa tumour resection in children: incomplete recovery on long-term follow-up.

INTRODUCTION: Mutism after posterior fossa tumour resection is generally said to be transient. Our experience suggested that speech did not usually normalise, and that mutism was associated with neurologic deficits that did not recover fully. METHODS: Children with mutism after posterior fossa tumour resection, and alive more than 2 years post-operatively, were reviewed retrospectively. Charts were reviewed and parents contacted to ascertain details about mutism, associated neurologic deficits, and the most recent speech and neurologic status. RESULTS: There were 7 children, with follow-up ranging from 2.5 to 13.1 years (mean 6.8 years). Tumours were midline, with 4 astrocytomas and 3 medulloblastomas. Mutism was noted immediately after post-operative extubation in all patients. Speech reappeared 1-15 weeks post-operatively, except for 1 patient, who remained mute at 2.5 years. Speech returned to normal in only 1 patient. Mutism was always accompanied by new or worsened cerebellar ataxia, which resolved incompletely in the long term. Sixth nerve palsies occurred in 3 and recovered incompletely. Seventh nerve paresis occurred in 2 and recovered completely. CONCLUSION: Mutism after posterior fossa tumour resection is associated with other neurologic deficits, particularly ataxia. Whereas speech usually returns, contrary to general opinion, speech rarely normalises. Other associated deficits rarely resolve completely. These findings have significant implications for counselling of family and patients.

Adolescent↗
PubMed2003

Conservative neurosurgical management of intracranial epidural abscesses in children.

OBJECTIVE: Traditional management of epidural abscesses caused by sinusitis in children involves neurosurgical drainage. With better techniques to drain affected sinuses, to identify causative organisms, and to guide medical therapy, some pediatric epidural intracranial abscesses may be treated effectively with sinus drainage and antibiotics, without an intracranial procedure. METHODS: Charts and computed tomographic scans of children with isolated intracranial epidural abscess associated with sinusitis who were treated in a pediatric hospital were reviewed retrospectively. RESULTS: Eight patients were treated between 1982 and 2002. All patients received antibiotic therapy appropriate to the causative organism(s). Four patients treated before mid-1997 had an intracranial procedure additionally (operative group, Group 1), and four patients treated thereafter did not (conservative group, Group 2). Abscesses had a mean size of 3 x 3 x 1 cm (length x width x depth) in both groups. All patients experienced clinical and radiographic resolution of the infection with treatment. In Group 1, neurosurgical management consisted of burr hole drainage in two patients and craniotomy in two patients. Extranasal otorhinolaryngological procedures for sinus drainage were performed in two patients. In Group 2, endonasal procedures were used in three patients for paranasal sinus infections to effect drainage and obtain specimens for culture. A radical mastoidectomy was required in the single patient with mastoiditis. Although two of four patients initially demonstrated transient worsening of headaches, all patients subsequently improved rapidly after the first week of treatment. Computed tomographic follow-up revealed minimal or no enlargement of the abscess or mass effect at 1 week, decrease or stable size at 2 weeks, and resolution by 6 weeks. CONCLUSION: Sinus-related intracranial epidural abscesses in children may be managed without neurosurgical procedures in the setting of adequate sinus drainage, appropriate antibiotic therapy, and minimal extradural mass effect from the abscess. Symptomatic worsening without significant increase in mass effect during the first week of therapy is not necessarily an indication for an intracranial drainage procedure.

Adolescent↗
PubMed2003

Optic pathway tumors in children.

Tumors of the optic pathways are sub-divided in this review into those that arise in one or both optic nerves anterior to the chiasm (optic nerve tumors); those that arise within the chiasm and do not extend significantly into the hypothalamus (optic chiasmatic tumors) and the large exophytic tumors that involve both the optic chiasm and the hypothalamus to a lesser or greater degree (optic chiasmatic/hypothalamic tumors). The management of optic chiasmatic gliomas is controversial, partly related to failure to separate out chiasmatic tumors from the chiasmatic/hypothalamic tumors. The optic nerve tumors are reviewed briefly, since they rarely extend intracranially. Chiasmatic tumors tend to be associated with NF1 and to behave almost like hamartomas. Close observation is usually the most appropriate management. On the other hand, chiasmatic/hypothalamic tumors grow like typical neoplasms. The tumors are almost uniformly low grade astrocytomas, but growth rates may berapid, especially in infants. Modern management has trended away from radical surgical resection, which has significant morbidity, to chemotherapy as the first line of treatment. In this review, the clinical presentation and management of different types of optic pathway tumors are discussed.

Child↗
PubMed2002

Selective dorsal rhizotomy: meta-analysis of three randomized controlled trials.

This study is a comparative analysis and meta-analysis of three randomized clinical trials. Children with spastic diplegia received either 'selective' dorsal rhizotomy (SDR) plus physiotherapy (SDR+PT) or PT without SDR (PT-only). Common outcome measures were used for spasticity (Ashworth scale) and function (Gross Motor Function Measure [GMFM]). Baseline and 9- to 12-month outcome data were pooled (n=90). At baseline, 82 children were under 8 years old and 65 had Gross Motor Function Classification System level II or III disability. Pooled Ashworth data analysis confirmed a reduction of spasticity with SDR+PT (mean change score difference -1.2; Wilcoxonp<0.001). Pooled GMFM data revealed greater functional improvement with SDR+PT (difference in change score +4.0, p=0.008). Multivariate analysis in the SDR+PT group revealed a direct relationship between percentage of dorsal root tissue transected and functional improvement. SDR+PT is efficacious in reducing spasticity in children with spastic diplegia and has a small positive effect on gross motor function.

Cerebral Palsy↗
PubMed2002

Validity of three measures of health-related quality of life in children with intractable epilepsy.

PURPOSE: Validity studies on health-related quality of life (HRQOL) scales for pediatric epilepsy are few, and cross-validation with other samples has not been reported. This study was designed to assess the validity of three parent-rated measures of HRQOL in pediatric epilepsy: (a) the Impact of Childhood Illness Scale (ICI), (b) the Impact of Child Neurologic Handicap Scale (ICNH), and (c) the Hague Restrictions in Epilepsy Scale (HARCES). METHODS: Retrospective data were examined for 44 children with intractable epilepsy. Validity was assessed by evaluating differences across epilepsy severity groups as well as correlations between HRQOL scales and neurologic variables (seizure severity, epilepsy duration, current/prior antiepileptic medications) and psychosocial measures (emotional functioning, IQ, social skills, adaptive behavior). Scale overlap with a global QOL rating also was assessed. RESULTS: The HRQOL measures were moderately to highly intercorrelated. The scales differed in terms of their associations with criterion measures. The HARCES was related to the highest number of neurologic variables and the ICNH to the fewest. All three scales were related to psychosocial functioning and to global quality of life. CONCLUSIONS: The results of this study suggest that the three measures are likely adequate measures of HRQOL for use in intractable childhood epilepsy. The measures were highly intercorrelated, and they were all broadly related to criterion measures reflecting specific domains of HRQOL as well as global QOL. Some differences between scales emerged, however, that suggest care in choosing HRQOL instruments for children with epilepsy.

Age of Onset↗
PubMed2002

A cost-effectiveness analysis of endoscopic third ventriculostomy.

OBJECTIVE: Endoscopic third ventriculostomy (ETV) is currently the principal alternative to cerebrospinal fluid shunt placement in the management of pediatric hydrocephalus. Cost-effectiveness analysis can help determine the optimal strategy for integrating these different approaches. METHODS: All patients (n = 28) who underwent ETV at British Columbia's Children's Hospital between 1989 and 1998 were matched for age, pathogenesis, and number of previous shunt procedures, with patients treated with cerebrospinal fluid shunts. To perform a cost-effectiveness analysis, hydrocephalus-related resource consumption and outcome (determined as the number of hydrocephalus treatment-free days during follow-up) were then retrospectively identified. Cost data were linked to resource use to provide a total cost for all resources used. Costs and outcomes were discounted annually at 5% by standard economic analysis methods. RESULTS: Twenty-four of 28 ETV patients had obstructive hydrocephalus. Over equivalent follow-up periods (median, 35 mo), the ETV success rate (defined by need for reoperation) was 54%. One hydrocephalus-related death and one hemiparesis occurred in the ETV group. No permanent procedure-related morbidity or mortality was seen in the shunt group. The cost/effect ratios for the two groups were similar. The additional incremental resource use by the shunt group included six readmissions and eight reoperations. ETV mean costs per patient were $10,570 +/- $7628, versus $10,922 +/- $8722 for the shunt group (Canadian dollars for the year 2000). Costs accrued more quickly for the shunt group as time passed. The additional incremental outcome benefit to the endoscopy group was 86 treatment-free days (3.07 d per patient [95% confidence interval, -7.56 to 13.70 d]). Neither of these differences was statistically significant. CONCLUSION: In this matched cohort, ETV was not significantly less costly or more effective over a median 35 months of follow-up, with a 54% initial ETV success rate, even before the additional morbidity and mortality encountered were taken into account. The time course for the accrued costs suggests that a larger cohort, longer follow-up, or higher success rates are needed to demonstrate the cost-effectiveness of this therapy.

Adolescent↗
PubMed2002

Comparison of motor outcomes after selective dorsal rhizotomy with and without preoperative intensified physiotherapy in children with spastic diplegic cerebral palsy.

A previous randomized clinical trial compared selective dorsal rhizotomy (SDR) plus postoperative intensified physiotherapy (group 1) with intensified physiotherapy alone (group 2) for children with spastic diplegic cerebral palsy. At the end of this trial, all patients in group 2 had an SDR, followed by further intensified physiotherapy. This study was performed to determine if the additional intensified physiotherapy before SDR, as occurred in group 2, improved long-term motor outcome. Outcomes were compared in the two groups, i.e. group 1 without intensified physiotherapy before SDR and group 2 with intensified physiotherapy before SDR. The primary outcome measure was the Gross Motor Function Measure (GMFM). Lower-limb spasticity, range and strength were secondary outcome measures. Baseline assessments had been done for the prior clinical trial. For this study, patients were reassessed by physiotherapists blinded to the treatment group. Thirteen children in each group were studied at a mean follow-up of 53 months. The mean improvement in GMFM was 10.0 in group 1 and 10.4 in group 2 (p = 0.9). Improvements in spasticity and range were similar in the two groups. There was no significant change in muscle strength in either group. It was concluded that in this relatively small series of patients, additional intensified physiotherapy before SDR did not improve motor outcomes.

Cerebral Palsy↗
PubMed2002

Reduction of transfusion rates in the surgical correction of sagittal synostosis.

OBJECT: As public concern about the risks of blood transfusions increased in the mid-1990s, avoidance of transfusions became a goal of surgery for sagittal synostosis. This study was performed to confirm a hypothesized reduction in transfusion rates in recent years and to identify factors associated with both the need for transfusion and low postoperative levels of hemoglobin. METHODS: Sagittal synostosis operations performed in children between 1986 and 1999 were reviewed retrospectively. Patients underwent a minimum of vertex strip craniectomy and parietal craniectomies. There were 118 patients whose median age at surgery was 4.2 months. The primary end point for analysis was defined as either the receipt of a blood transfusion or a postoperative level of hemoglobin less than 70 g/L. Forty-two percent of patients (95% confidence interval [CI] 31-52%) treated before 1996 and 11% of patients (95% CI 0-23%) treated from 1996 onward received blood. The reduction in the blood transfusion rate in later years was, in part, related to the acceptance of a lower postoperative hemoglobin level, often below 70 g/L. A univariate analysis showed that the only patient or surgical factors that correlated with reaching the primary end point in a statistically significant manner were the year of surgery and the extent of surgery. A logistic regression of the age and weight of the child, length of surgery time (from skin opening to skin closure), preoperative hemoglobin level, extent of surgery, and surgeon against the primary end point revealed that the best predictor of the need for a blood transfusion or the presence of a postoperative hemoglobin level lower than 70 g/L was the extent of surgery (beta = 1.4, standard error of the beta statistic = 0.44). Once the extent of surgery was accounted for in the model, no other covariates significantly improved the model. Techniques implemented to minimize blood loss since 1995 included the following: use of the Colorado needle for scalp incision, selection of the Midas Rex craniotome for cranial cuts, and application of microfibrillar collagen. Postoperative hemoglobin was allowed to decrease to 60 g/L if the child was stable hemodynamically, before blood was administered. There were no cardiovascular, wound healing, or infectious complications, and no surgeries were repeated for cosmetic reasons. CONCLUSIONS: Low blood transfusion rates were achieved using simple intraoperative techniques and by accepting a low level of postoperative hemoglobin.

Blood Loss, Surgical↗