Lissa C. Baird

Discovery of asymptomatic moyamoya arteriopathy in pediatric syndromic populations: Radiographic and clinical progression

OBJECT Limited data exist to guide management of incidentally discovered pediatric moyamoya. Best exemplified in the setting of unilateral moyamoya, in which the unaffected side is monitored, this phenomenon also occurs in populations undergoing routine surveillance of the cerebral vasculature for other conditions, such as sickle cell disease (SCD) or neurofibromatosis Type 1 (NF1). The authors present their experience with specific syndromic moyamoya populations to better characterize the natural history of radiographic and clinical progression in patients with asymptomatic moyamoya. METHODS The authors performed a retrospective review of the clinical database of the neurosurgery department at Childrens Hospital Boston, including both nonoperative referrals and a consecutive series of 418 patients who underwent surgical revascularization for moyamoya disease between 1988 and 2010. RESULTS Within the period of time studied, 83 patients were asymptomatic at the time of radiographic diagnosis of moyamoya, while also having either unilateral moyamoya or moyamoya in association with either SCD or NF1. The mean age at presentation was 9.1 years (range 1-21 years), and there were 49 female (59%) and 34 male (41%) patients. The mean follow-up duration was 5.4 ± 3.8 years (mean ± SD), with 45 patients (54%) demonstrating radiographic progression and 37 (45%) becoming symptomatic within this period. Patients with SCD had the highest incidence of both radiographic (15 patients [75%]) and clinical (13 patients [65%]) progression, followed by NF1 (20 patients [59%] with radiographic progression and 15 patients [44%] with clinical progression) and patients with unilateral moyamoya (10 patients [35%] with radiographic progression and 9 patients [31%] with clinical progression). CONCLUSIONS Radiographic progression occurred in the majority of asymptomatic patients and generally heralded subsequent clinical symptoms. These data demonstrate that moyamoya is a progressive disorder, even in asymptomatic populations, and support the rationale of early surgical intervention to minimize morbidity from stroke.

Pediatric hydrocephalus: systematic literature review and evidence-based guidelines. Part 7: Antibiotic-impregnated shunt systems versus conventional shunts in children: a systematic review and meta-analysis

OBJECT The objective of this systematic review and meta-analysis was to answer the following question: Are antibiotic-impregnated shunts (AISs) superior to standard shunts (SSs) at reducing the risk of shunt infection in pediatric patients with hydrocephalus? METHODS Both the US National Library of Medicine PubMed/MEDLINE database and the Cochrane Database of Systematic Reviews were queried using MeSH headings and key words relevant to AIS use in children. Abstracts were reviewed, after which studies meeting the inclusion criteria were selected. An evidentiary table was assembled summarizing the studies and the quality of their evidence (Classes I-III). A meta-analysis was conducted using a random-effects model to calculate a cumulative estimate of treatment effect using risk ratio (RR). Heterogeneity was assessed using the chi-square and I(2) statistics. Based on the quality of the literature and the result of the meta-analysis, a recommendation was rendered (Level I, II, or III). RESULTS Six studies, all Class III, met our inclusion criteria. All but one study focused on a retrospective cohort and all but one were conducted at a single institution. Four of the studies failed to demonstrate a lowered infection rate with the use of an AIS. However, when the data from individual studies were pooled together, the infection rate in the AIS group was 5.5% compared with 8.6% in the SS group. Using a random-effects model, the cumulative RR was 0.51 (95% CI 0.29-0.89, p < 0.001), indicating that a shunt infection was 1.96 times more likely in patients who received an SS. CONCLUSIONS We recommend AIS tubing because of the associated lower risk of shunt infection compared to the use of conventional silicone hardware (quality of evidence: Class III; strength of recommendation: Level III). RECOMMENDATION Antibiotic-impregnated shunt (AIS) tubing may be associated with a lower risk of shunt infection compared with conventional silicone hardware and thus is an option for children who require placement of a shunt. STRENGTH OF RECOMMENDATION Level III, unclear degree of clinical certainty.

Vagus nerve stimulation therapy in patients with autism spectrum disorder and intractable epilepsy: Results from the vagus nerve stimulation therapy patient outcome registry - Clinical article

OBJECT The purpose of this study was to determine the effectiveness of vagus nerve stimulation (VNS) therapy on quality-of-life (QOL) variables among patients with both autism spectrum disorder (ASD) and persistent or recurrent intractable epilepsy. METHODS Data were obtained from the VNS therapy patient outcome registry, which was established after US FDA approval of the VNS device in 1997 as a means of capturing open-label clinical data outside of protocol. The integrity of the systems for collecting and processing registry data was authenticated by an independent auditing agency. The effect of potential selection bias, however, remains uncertain. RESULTS Two cohorts were compared: 1) patients with epilepsy but without ASD (non-ASD [NASD] Group, 315 patients) who were being tracked in the registry (this cohort, which was controlled for age, included patients 20 years of age or younger); and 2) patients with a diagnosis of ASD who underwent implantation of the VNS device (ASD Group, 77 patients). Differences between the ASD and NASD groups were noted in the following categories: sex (male preponderance in ASD); normal imaging results (MR imaging results normal in ASD); depression (less common in ASD); behavioral problems (more common in ASD); neurological deficit (more common in ASD); mental retardation (more common in ASD); and developmental delay. The only QOL difference between the ASD and NASD groups was noted in mood at 12 months postimplant (mood was improved in ASD) (p = 0.04). There were no other differences in the QOL variables. CONCLUSIONS Patients with ASD and intractable epilepsy respond as favorably as all other patients receiving VNS therapy. In addition, they may experience a number of QOL improvements, some of which exceed those classically observed following placement of a VNS device.

Pediatric hydrocephalus: systematic literature review and evidence-based guidelines. Part 4: Cerebrospinal fluid shunt or endoscopic third ventriculostomy for the treatment of hydrocephalus in children

OBJECT The objective of this systematic review was to examine the existing literature comparing CSF shunts and endoscopic third ventriculostomy (ETV) for the treatment of pediatric hydrocephalus and to make evidence-based recommendations regarding the selection of surgical technique for this condition. METHODS Both the US National Library of Medicine and the Cochrane Database of Systematic Reviews were queried using MeSH headings and key words specifically chosen to identify published articles detailing the use of CSF shunts and ETV for the treatment of pediatric hydrocephalus. Articles meeting specific criteria that had been determined a priori were examined, and data were abstracted and compiled in evidentiary tables. These data were then analyzed by the Pediatric Hydrocephalus Systematic Review and Evidence-Based Guidelines Task Force to consider treatment recommendations based on the evidence. RESULTS Of the 122 articles identified using optimized search parameters, 52 were recalled for full-text review. One additional article, originally not retrieved in the search, was also reviewed. Fourteen articles met all study criteria and contained comparative data on CSF shunts and ETV. In total, 6 articles (1 Class II and 5 Class III) were accepted for inclusion in the evidentiary table; 8 articles were excluded for various reasons. The tabulated evidence supported the evaluation of CSF shunts versus ETV. CONCLUSIONS Cerebrospinal fluid shunts and ETV demonstrated equivalent outcomes in the clinical etiologies studied. RECOMMENDATION Both CSF shunts and ETV are options in the treatment of pediatric hydrocephalus. STRENGTH OF RECOMMENDATION Level II, moderate clinical certainty.

Pediatric hydrocephalus: systematic literature review and evidence-based guidelines. Part 5: Effect of valve type on cerebrospinal fluid shunt efficacy.

OBJECT The objective of this systematic review was to examine the existing literature to compare differing shunt components used to treat hydrocephalus in children, find whether there is a superior shunt design for the treatment of pediatric hydrocephalus, and make evidence-based recommendations for the selection of shunt implants when placing shunts. METHODS Both the US National Library of Medicine PubMed/MEDLINE database and the Cochrane Database of Systematic Reviews were queried using MeSH headings and key words chosen to identify publications comparing the use of shunt implant components. Abstracts of these publications were reviewed, after which studies meeting the inclusion criteria were selected. An evidentiary table was compiled summarizing the selected articles and quality of evidence. These data were then analyzed by the Pediatric Hydrocephalus Systematic Review and Evidence-Based Guidelines Task Force to consider evidence-based treatment recommendations. RESULTS Two hundred sixty-nine articles were identified using the search parameters, and 43 articles were recalled for full-text review. Of these, 22 papers met the study criteria for a comparison of shunt components and were included in the evidentiary table. The included studies consisted of 1 Class I study, 11 Class II studies, and 10 Class III studies. The remaining 21 articles were excluded. CONCLUSIONS An analysis of the evidence did not demonstrate a clear advantage for any specific shunt component, mechanism, or valve design over another. RECOMMENDATION There is insufficient evidence to demonstrate an advantage for one shunt hardware design over another in the treatment of pediatric hydrocephalus. Current designs described in the evidentiary tables are all treatment options. STRENGTH OF RECOMMENDATION Level I, high degree of clinical certainty. RECOMMENDATION There is insufficient evidence to recommend the use of a programmable valve versus a nonprogrammable valve. Programmable and nonprogrammable valves are both options for the treatment of pediatric hydrocephalus. STRENGTH OF RECOMMENDATION Level II, moderate degree of clinical certainty.

Mortality resulting from head injury in professional boxing

BACKGROUND:The majority of boxing-related fatalities result from traumatic brain injury. Biomechanical forces in boxing result in rotational acceleration with resultant subdural hematoma and diffuse axonal injury. OBJECTIVE:Given the inherent risk and the ongoing criticism boxing has received, we evaluated mortalities associated with professional boxing. METHODS:We used the Velaquez Fatality Collection of boxing injuries and supplementary sources to analyze mortality from 1950 to 2007. Variables evaluated included age at time of death, association with knockout or other outcome of match, rounds fought, weight class, location of fight, and location of pretermial event. RESULTS:There were 339 mortalities between 1950 and 2007 (mean age, 24 ± 3.8 years); 64% were associated with knockout and 15% with technical knockout. A higher percentage occured in the lower weight classes. The preterminal event occured in the ring (61%), in the locker room (17%), and outside the arena (22%), We evaluated for significant changes after 1983 when championship bouts were reduced from 15 to 12 rounds. CONCLUSION:There was a significant decline in mortality after 1983. We found no significant variables to support that this decline is related to a reduction in rounds. Rather, we hypothesize the decline to be the result of a reduction in exposure to repetitive head trauma (shorter careers and fewer fights), along with increased medical oversight and stricter safety regulations. Increased efforts should be made to improve medical supervisions of boxers. Mandatory central nervous system imaging after a knockout could lead to a significant reduction in associated mortality

Moyamoya Syndrome Associated with Alagille Syndrome: Outcome after Surgical Revascularization

Vasculopathy is well-described in Alagille syndrome (ALGS); however, few data exist regarding neurosurgical interventions. We report 5 children with ALGS with moyamoya who underwent revascularization surgery. Postsurgical complications included 1 stroke and 1 death from thalamic hemorrhage. Global function improved in survivors. Revascularization is reasonably safe in patients with ALGS and may improve neurologic outcomes.

Results of a North American survey of rapid-sequence MRI utilization to evaluate cerebral ventricles in children

OBJECT Growing concern about potential adverse effects of ionizing radiation exposure during imaging studies is particularly relevant to the pediatric population. To decrease radiation exposure, many institutions use rapid-sequence (or quick-brain) MRI to evaluate cerebral ventricle size. There are obstacles, however, to widespread implementation of this imaging modality. The purpose of this study was to define and quantify these obstacles to positively affect institutional and governmental policy. METHODS A 9-question survey was emailed to pediatric neurosurgeons who were either members or candidate members of the American Society of Pediatric Neurosurgeons at every one of 101 institutions in the US and Canada having such a neurosurgeon on staff. Responses were compiled and descriptive statistics were performed. RESULTS Fifty-six institutions completed the survey. Forty-four (79%) of the 56 institutions currently have a rapid-sequence MRI protocol to evaluate ventricle size, while 36 (64%) use it routinely. Of the 44 institutions with a rapid-sequence MRI protocol, 29 (66%) have had a rapid-sequence MRI protocol for less than 5 years while 39 (89%) have had a rapid-sequence MRI protocol for no more than 10 years. Thirty-six (88%) of 41 rapid-sequence MRI users responding to this question obtain a T2-weighted rapid-sequence MRI while 13 (32%) obtain a T1-weighted rapid-sequence MRI. Twenty-eight (64%) of 44 institutions never use sedation while an additional 12 (27%) rarely use sedation to obtain a rapid-sequence MRI (less than 5% of studies). Of the institutions with an established rapid-sequence MRI protocol, obstacles to routine use include lack of emergency access to MRI facilities in 18 (41%), lack of staffing of MRI facilities in 12 (27%), and the inability to reimburse a rapid-sequence MRI protocol in 6 (14%). In the 12 institutions without rapid-sequence MRI, obstacles to implementation include lack of emergency access to MRI facilities in 8 (67%), lack of staffing of MRI facilities in 7 (58%), the inability to reimburse in 3 (25%), and lack of administrative support in 3 (25%). To evaluate pediatric head trauma, 53 (96%) of 55 institutions responding to this question use noncontrast CT, no institution uses rapid-sequence MRI, and only 2 (4%) use standard MRI. CONCLUSIONS Many North American institutions have a rapid-sequence MRI protocol to evaluate ventricle size, with most developing this technique within the past 5 years. Most institutions never use sedation, and most obtain T2-weighted sequences. The greatest obstacles to the routine use of rapid-sequence MRI in institutions with and in those without a rapid-sequence MRI protocol are the lack of emergency access and staffing of the MRI facility during nights and weekends.

Third-ventricular neurocysticercosis: hydraulic maneuvers facilitating endoscopic resection

BackgroundNeurocysticercosis, an infection of the central nervous system with the larval cysts of the pork tapeworm, Taenia solium, is the most common parasitic disease of the central nervous system. The disease is a major global cause of acquired epilepsy and may also manifest as intracranial hypertension due to mass effect from large cysts or to cerebrospinal fluid flow obstruction by intraventricular cysts or inflammation of the subarachnoid space. While the condition is endemic in several regions of the world and has been appreciated as a public health problem in such regions for several decades, its emergence in the USA in areas far from the Mexican border is a more recent phenomenon.MethodsWe present a case of surgically corrected acute hydrocephalus in a recent Haitian emigrant child due to a third ventricular neurocysticercal cyst complex.ResultsWe describe the endoscope-assisted en bloc removal of the complex, together with hydraulic maneuvers facilitating the removal of the intact cyst.ConclusionsSimple hydraulic maneuvers can facilitate the endoscopic en bloc removal of third ventricular neurocysticercal cysts.

Mortality resulting from head injury in professional boxing: case report

BACKGROUNDThe majority of boxing-related fatalities result from traumatic brain injury. Biomechanical forces in boxing result in rotational acceleration with resultant subdural hematoma and diffuse axonal injury. OBJECTIVEGiven the inherent risk and the ongoing criticism boxing has received, we evaluated mortalities associated with professional boxing. METHODSWe used the Velazquez Fatality Collection of boxing injuries and supplementary sources to analyze mortality from 1950 to 2007. Variables evaluated included age at time of death, association with knockout or other outcome of match, rounds fought, weight class, location of fight, and location of preterminal event. RESULTSThere were 339 mortalities between 1950 and 2007 (mean age, 24 ± 3.8 years); 64% were associated with knockout and 15% with technical knockout. A higher percentage occurred in the lower weight classes. The preterminal event occurred in the ring (61%), in the locker room (17%), and outside the arena (22%). We evaluated for significant changes after 1983 when championship bouts were reduced from 15 to 12 rounds. CONCLUSIONThere was a significant decline in mortality after 1983. We found no significant variables to support that this decline is related to a reduction in rounds. Rather, we hypothesize the decline to be the result of a reduction in exposure to repetitive head trauma (shorter careers and fewer fights), along with increased medical oversight and stricter safety regulations. Increased efforts should be made to improve medical supervision of boxers. Mandatory central nervous system imaging after a knockout could lead to a significant reduction in associated mortality.