Mandeep S. Tamber

Endoscopic third ventriculostomy and choroid plexus cauterization in infants with hydrocephalus: a retrospective Hydrocephalus Clinical Research Network study

OBJECT The use of endoscopic third ventriculostomy (ETV) with choroid plexus cauterization (CPC) has been advocated as an alternative to CSF shunting in infants with hydrocephalus. There are limited reports of this procedure in the North American population, however. The authors provide a retrospective review of the experience with combined ETV + CPC within the North American Hydrocephalus Clinical Research Network (HCRN). METHODS All children (< 2 years old) who underwent an ETV + CPC at one of 7 HCRN centers before November 2012 were included. Data were collected retrospectively through review of hospital records and the HCRN registry. Comparisons were made to a contemporaneous cohort of 758 children who received their first shunt at < 2 years of age within the HCRN. RESULTS Thirty-six patients with ETV + CPC were included (13 with previous shunt). The etiologies of hydrocephalus were as follows: intraventricular hemorrhage of prematurity (9 patients), aqueductal stenosis (8), myelomeningocele (4), and other (15). There were no major intraoperative or early postoperative complications. There were 2 postoperative CSF infections. There were 2 deaths unrelated to hydrocephalus and 1 death from seizure. In 18 patients ETV + CPC failed at a median time of 30 days after surgery (range 4-484 days). The actuarial 3-, 6-, and 12-month success for ETV + CPC was 58%, 52%, and 52%. Time to treatment failure was slightly worse for the 36 patients with ETV + CPC compared with the 758 infants treated with shunts (p = 0.012). Near-complete CPC (≥ 90%) was achieved in 11 cases (31%) overall, but in 50% (10 of 20 cases) in 2012 versus 6% (1 of 16 cases) before 2012 (p = 0.009). Failure was higher in children with < 90% CPC (HR 4.39, 95% CI 0.999-19.2, p = 0.0501). CONCLUSIONS The early North American multicenter experience with ETV + CPC in infants demonstrates that the procedure has reasonable safety in selected cases. The degree of CPC achieved might be associated with a surgeons learning curve and appears to affect success, suggesting that surgeon training might improve results.

Neurosurgical management of intractable rolandic epilepsy in children: role of resection in eloquent cortex. Clinical article.

OBJECT The authors undertook this study to review their experience with cortical resections in the rolandic region in children with intractable epilepsy. METHODS The authors retrospectively reviewed the medical records obtained in 22 children with intractable epilepsy arising from the rolandic region. All patients underwent preoperative electroencephalography (EEG), MR imaging, prolonged video-EEG recordings, functional MR imaging, magnetoencephalography, and in some instances PET/SPECT studies. In 21 patients invasive subdural grid and depth electrode monitoring was performed. Resection of the epileptogenic zones in the rolandic region was undertaken in all cases. Seizure outcome was graded according to the Engel classification. Functional outcome was determined using validated outcome scores. RESULTS There were 10 girls and 12 boys, whose mean age at seizure onset was 3.2 years. The mean age at surgery was 10 years. Seizure duration prior to surgery was a mean of 7.4 years. Nine patients had preoperative hemiparesis. Neuropsychological testing revealed impairment in some domains in 19 patients in whom evaluation was possible. Magnetic resonance imaging abnormalities were identified in 19 patients. Magnetoencephalography was performed in all patients and showed perirolandic spike clusters on the affected side in 20 patients. The mean duration of invasive monitoring was 4.2 days. The mean number of seizures during the period of invasive monitoring was 17. All patients underwent resection that involved primary motor and/or sensory cortex. The most common pathological entity encountered was cortical dysplasia, in 13 children. Immediately postoperatively, 20 patients had differing degrees of hemiparesis, from mild to severe. The hemiparesis improved in all affected patients by 3-6 months postoperatively. With a mean follow-up of 4.1 years (minimum 2 years), seizure outcome in 14 children (64%) was Engel Class I and seizure outcome in 4 (18%) was Engel Class II. In this series, seizure outcome following perirolandic resection was intimately related to the childs age at the time of surgery. By univariate logistic regression analysis, age at surgery was a statistically significant factor predicting seizure outcome (p < 0.024). CONCLUSIONS Resection of rolandic cortex for intractable epilepsy is possible with expected morbidity. Accurate mapping of regions of functional cortex and epileptogenic zones may lead to improved seizure outcome in children with intractable rolandic epilepsy. It is important to counsel patients and families preoperatively to prepare them for possible worsened functional outcome involving motor, sensory and/or language pathways.

Complications in 622 Cases of Frame-Based Stereotactic Biopsy, a Decreasing Procedure

BACKGROUND Frame-based stereotactic brain biopsy has played an important role in the management of patients with suspected neoplastic intracranial lesions over the last three decades. We reviewed the surgical experience of one surgeon to determine the nature and frequency of complications associated with this procedure. METHODS Records were reviewed for 858 patients undergoing frame-based stereotactic procedures from January 1986 to May 2006. Data on each case were prospectively collected by the senior author. Procedures for Ommaya reservoir placement, brachytherapy, stereotactic craniotomy flap localization, shunt placement, or treatment of previously-diagnosed intracranial cystic lesions were excluded, leaving 614 patients in whom a total of 622 procedures were performed for purely diagnostic purposes. Complication rates and their association with clinical variables were sought. RESULTS Morbidity and mortality rates were 6.9% (43/622) and 1.3% (8/622), respectively. The risk of symptomatic hemorrhage (intracerebral hemorrhage [ICH], subarachnoid hemorrhage [SAH], intraventricular hemorrhage [IVH]) was 4.8%. The risks of transient or permanent neurological deficits were 2.9% (18/622) and 1.5% (9/622), respectively. Biopsy of deep-seated lesions was associated with increased overall complication rate, while biopsy of Glioblastoma Multiforme (GBM) was associated with perioperative mortality. CONCLUSIONS Overall, complication rates were comparable with those in previous reports. The subgroup of patients with deep-seated lesions or a histologic diagnosis of GBM may possess an elevated risk of overall complications or mortality, respectively, compared to other patients undergoing frame-based stereotactic brain biopsy.

Risk Factors for First Cerebrospinal Fluid Shunt Infection: Findings from a Multi-Center Prospective Cohort Study

OBJECTIVE To quantify the extent to which cerebrospinal fluid (CSF) shunt revisions are associated with increased risk of CSF shunt infection, after adjusting for patient factors that may contribute to infection risk. STUDY DESIGN We used the Hydrocephalus Clinical Research Network registry to assemble a large prospective 6-center cohort of 1036 children undergoing initial CSF shunt placement between April 2008 and January 2012. The primary outcome of interest was first CSF shunt infection. Data for initial CSF shunt placement and all subsequent CSF shunt revisions prior to first CSF shunt infection, where applicable, were obtained. The risk of first infection was estimated using a multivariable Cox proportional hazard model accounting for patient characteristics and CSF shunt revisions, and is reported using hazard ratios (HRs) with 95% CI. RESULTS Of the 102 children who developed first infection within 12 months of placement, 33 (32%) followed one or more CSF shunt revisions. Baseline factors independently associated with risk of first infection included: gastrostomy tube (HR 2.0, 95% CI, 1.1, 3.3), age 6-12 months (HR 0.3, 95% CI, 0.1, 0.8), and prior neurosurgery (HR 0.4, 95% CI, 0.2, 0.9). After controlling for baseline factors, infection risk was most significantly associated with the need for revision (1 revision vs none, HR 3.9, 95% CI, 2.2, 6.5; ≥2 revisions, HR 13.0, 95% CI, 6.5, 24.9). CONCLUSIONS This study quantifies the elevated risk of infection associated with shunt revisions observed in clinical practice. To reduce risk of infection risk, further work should optimize revision procedures.

Outcomes of CSF shunting in children: comparison of Hydrocephalus Clinical Research Network cohort with historical controls

OBJECT The Hydrocephalus Clinical Research Network (HCRN), which comprises 7 pediatric neurosurgical centers in North America, provides a unique multicenter assessment of the current outcomes of CSF shunting in nonselected patients. The authors present the initial results for this cohort and compare them with results from prospective multicenter trials performed in the 1990s. METHODS Analysis was restricted to patients with newly diagnosed hydrocephalus undergoing shunting for the first time. Detailed perioperative data from 2008 through 2012 for all HCRN centers were prospectively collected and centrally stored by trained research coordinators. Historical control data were obtained from the Shunt Design Trial (1993-1995) and the Endoscopic Shunt Insertion Trial (1996-1999). The primary outcome was time to first shunt failure, which was determined by using Cox regression survival analysis. RESULTS Mean age of the 1184 patients in the HCRN cohort was older than mean age of the 720 patients in the historical cohort (2.51 years vs 1.60 years, p < 0.0001). The distribution of etiologies differed (p < 0.0001, chi-square test); more tumors and fewer myelomeningoceles caused the hydrocephalus in the HCRN cohort patients. The hazard ratio for first shunt failure significantly favored the HCRN cohort, even after the model was adjusted for the prognostic effects of age and etiology (adjusted HR 0.82, 95% CI 0.69-0.96). CONCLUSIONS Current outcomes of shunting in general pediatric neurosurgery practice have improved over those from the 1990s, although the reasons remain unclear.

Risk factors for shunt malfunction in pediatric hydrocephalus: a multicenter prospective cohort study

OBJECT The rate of CSF shunt failure remains unacceptably high. The Hydrocephalus Clinical Research Network (HCRN) conducted a comprehensive prospective observational study of hydrocephalus management, the aim of which was to isolate specific risk factors for shunt failure. METHODS The study followed all first-time shunt insertions in children younger than 19 years at 6 HCRN centers. The HCRN Investigator Committee selected, a priori, 21 variables to be examined, including clinical, radiographic, and shunt design variables. Shunt failure was defined as shunt revision, subsequent endoscopic third ventriculostomy, or shunt infection. Important a priori-defined risk factors as well as those significant in univariate analyses were then tested for independence using multivariate Cox proportional hazard modeling. RESULTS A total of 1036 children underwent initial CSF shunt placement between April 2008 and December 2011. Of these, 344 patients experienced shunt failure, including 265 malfunctions and 79 infections. The mean and median length of follow-up for the entire cohort was 400 days and 264 days, respectively. The Cox model found that age younger than 6 months at first shunt placement (HR 1.6 [95% CI 1.1-2.1]), a cardiac comorbidity (HR 1.4 [95% CI 1.0-2.1]), and endoscopic placement (HR 1.9 [95% CI 1.2-2.9]) were independently associated with reduced shunt survival. The following had no independent associations with shunt survival: etiology, payer, center, valve design, valve programmability, the use of ultrasound or stereotactic guidance, and surgeon experience and volume. CONCLUSIONS This is the largest prospective study reported on children with CSF shunts for hydrocephalus. It confirms that a young age and the use of the endoscope are risk factors for first shunt failure and that valve type has no impact. A new risk factor-an existing cardiac comorbidity-was also associated with shunt failure.

Outcomes of CSF shunting in children: comparison of Hydrocephalus Clinical Research Network cohort with historical controls: clinical article.

OBJECT The Hydrocephalus Clinical Research Network (HCRN), which comprises 7 pediatric neurosurgical centers in North America, provides a unique multicenter assessment of the current outcomes of CSF shunting in nonselected patients. The authors present the initial results for this cohort and compare them with results from prospective multicenter trials performed in the 1990s. METHODS Analysis was restricted to patients with newly diagnosed hydrocephalus undergoing shunting for the first time. Detailed perioperative data from 2008 through 2012 for all HCRN centers were prospectively collected and centrally stored by trained research coordinators. Historical control data were obtained from the Shunt Design Trial (1993-1995) and the Endoscopic Shunt Insertion Trial (1996-1999). The primary outcome was time to first shunt failure, which was determined by using Cox regression survival analysis. RESULTS Mean age of the 1184 patients in the HCRN cohort was older than mean age of the 720 patients in the historical cohort (2.51 years vs 1.60 years, p < 0.0001). The distribution of etiologies differed (p < 0.0001, chi-square test); more tumors and fewer myelomeningoceles caused the hydrocephalus in the HCRN cohort patients. The hazard ratio for first shunt failure significantly favored the HCRN cohort, even after the model was adjusted for the prognostic effects of age and etiology (adjusted HR 0.82, 95% CI 0.69-0.96). CONCLUSIONS Current outcomes of shunting in general pediatric neurosurgery practice have improved over those from the 1990s, although the reasons remain unclear.

Prospective surveillance of complications in a pediatric neurosurgery unit: Clinical article

OBJECT Complications of specific pediatric neurosurgical procedures are well recognized. However, focused surveillance on a specific neurosurgical unit, for all procedures, may lead to better understanding of the most important complications, and allow targeted strategies for quality improvement. METHODS The authors prospectively recorded the morbidity and mortality events at a large pediatric neurosurgical unit over a 2-year period. Morbidity was defined as any significant adverse outcome or death (for obstructive shunt failure, within 30 days). Multiple and unrelated complications in the same patient were recorded as separate events. RESULTS There were 1082 surgical procedures performed during the evaluation period. One hundred seventy-seven complications (16.4%) occurred in 147 patients. By procedure, the most common complications occurred in vascular surgery (41.7%) and brain tumor surgery (27.9%). The most common complications were CSF leakage (31 cases), a new neurological deficit (27 cases), early shunt or endoscopic third ventriculostomy obstruction (27 cases), and shunt infection (24 cases). Meningitis occurred in 19 cases: in 58% of shunt infections, 13% of CSF leaks, and 10% of wound infections. Sixty-four percent of adverse events required a second procedure, most commonly an external ventricular drain placement or shunt revision. CONCLUSIONS Complications in pediatric neurosurgical procedures are common, result in significant morbidity, and more than half the time require a repeat surgical procedure. Targeted strategies to prevent common complications, such as shunt infections or CSF leaks, might significantly reduce this burden.

Hemispherectomy for the control of intractable epilepsy in childhood: comparison of 2 surgical techniques in a single institution.

BACKGROUND: Hemispherectomy is an established neurosurgical procedure for catastrophic epilepsy in childhood. However, the technique used to achieve an optimum outcome remains to be determined. OBJECTIVE: We examined the influence of hemidecortication (HD) vs peri-insular hemispherotomy (PIH) on patient outcome. METHODS: The medical records of 41 children undergoing hemispherectomy were reviewed for patient demographics, clinical criteria, and surgical outcomes. RESULTS: HD and PIH were performed in 21 and 20 children, respectively. The mean age at surgery for HD was 54 months and 61 months for PIH. The median durations of surgery for HD and PIH were 5 hours and 7 hours, respectively (P < .001). For HD, 6 patients required a second surgery and 3 required a third. One PIH patient required a second procedure. Postoperative shunting was required in 5 HD patients, but only 1 PIH patient. All patients had increased hemiparesis after surgery. The overall mean follow-up time was 72 months. Engel class I or II outcomes after initial surgery were better after PIH (85%) compared with HD (48%) (P < .02). After subsequent surgeries for seizure control, 4 HD patients and 1 PIH patient improved to Engel class I or II. CONCLUSION: Hemispherectomy is an effective surgical procedure for childhood intractable catastrophic epilepsy. In patients with diffuse hemispheric disorder, PIH tends to have fewer major complications, more favorable seizure outcomes, and a decreased need for subsequent surgical procedures, including shunting for hydrocephalus, compared with HD.

Pediatric hydrocephalus: systematic literature review and evidence-based guidelines. Part 8: Management of cerebrospinal fluid shunt infection

OBJECT The objective of this systematic review was to answer the following question: What is the optimal treatment strategy for CSF shunt infection in pediatric patients with hydrocephalus? METHODS The US National Library of Medicine and the Cochrane Database of Systematic Reviews were queried using MeSH headings and key words relevant to the objective of this systematic review. Abstracts were reviewed, after which studies meeting the inclusion criteria were selected and graded according to their quality of evidence (Classes I-III). Evidentiary tables were constructed that summarized pertinent study results, and based on the quality of the literature, recommendations were made (Levels I-III). RESULTS A review and critical appraisal of 27 studies that met the inclusion criteria allowed for a recommendation for supplementation of antibiotic treatment using partial (externalization) or complete shunt hardware removal, with a moderate degree of clinical certainty. However, a recommendation regarding whether complete shunt removal is favored over partial shunt removal (that is, externalization) could not be made owing to severe methodological deficiencies in the existing literature. There is insufficient evidence to recommend the use of intrathecal antibiotic therapy as an adjunct to systemic antibiotic therapy in the management of routine CSF shunt infections. This also holds true for other clinical scenarios such as when an infected CSF shunt cannot be completely removed, when a shunt must be removed and immediately replaced in the face of ongoing CSF infection, or when the setting is ventricular shunt infection caused by specific organisms (for example, gram-negative bacteria). CONCLUSIONS Supplementation of antibiotic treatment with partial (externalization) or complete shunt hardware removal are options in the management of CSF shunt infection. There is insufficient evidence to recommend either shunt externalization or complete shunt removal as the preferred surgical strategy for the management of CSF shunt infection. Therefore, clinical judgment is required. In addition, there is insufficient evidence to recommend the combination of intrathecal and systemic antibiotics for patients with CSF shunt infection when the infected shunt hardware cannot be fully removed, when the shunt must be removed and immediately replaced, or when the CSF shunt infection is caused by specific organisms. The potential neurotoxicity of intrathecal antibiotic therapy may limit its routine use. RECOMMENDATION Supplementation of antibiotic treatment with partial (externalization) or with complete shunt hardware removal is an option in the management of CSF shunt infection. STRENGTH OF RECOMMENDATION Level II, moderate degree of clinical certainty. RECOMMENDATION There is insufficient evidence to recommend either shunt externalization or complete shunt removal as a preferred surgical strategy for the management of CSF shunt infection. Therefore, clinical judgment is required. STRENGTH OF RECOMMENDATION Level III, unclear degree of clinical certainty. RECOMMENDATION There is insufficient evidence to recommend the combination of intrathecal and systemic antibiotics for patients with CSF shunt infection in whom the infected shunt hardware cannot be fully removed or must be removed and immediately replaced, or when the CSF shunt infection is caused by specific organisms. The potential neurotoxicity of intrathecal antibiotic therapy may limit its routine use. STRENGTH OF RECOMMENDATION Level III, unclear degree of clinical certainty.