John R. W. Kestle
John R. W. Kestle
John R. W. Kestle
John R. W. Kestle
Report of five cases and review of the literature
Daniel R. Fassett, James Pingree, and John R. W. Kestle
P Myxopapillary ependymomas (MPEs) have historically been thought to be benign tumors occurring most frequently in adults. Only 8 to 20% of these tumors occur in the first two decades of life, making this tumor a rarity in pediatric neurosurgery. Five patients with intraspinal MPEs were treated by the authors between 1992 and 2003. Four (80%) of these five patients suffered from disseminated disease of the central nervous system (CNS) at the time of presentation; this incidence is much higher than that reported in the combined adult and pediatric literature.
Combining five pediatric case series reported in the literature with the present series, the authors review a total of 26 cases of pediatric patients with intraspinal MPEs. In nine cases (35%) CNS metastases occurred. In those cases in which patients underwent screening for CNS tumor dissemination, however, the incidence of disseminated disease was 58% (seven of 12 patients).
In pediatric patients MPEs may spread throughout the CNS via cerebrospinal fluid pathways; therefore, MR imaging of the entire CNS axis is recommended at both presentation and follow-up review to detect tumor dissemination.
Ricky R. Kalra and John R. W. Kestle
Various bibliometric indices are now commonly used to assess academic productivity in medicine. Some evidence suggests that these measures are specific to subspecialty areas. The authors' goal was to measure the h index of academic pediatric neurosurgeons and compare it with previously reported results for academic neurosurgeons in general.
Programs with an Accreditation Council for Pediatric Neurosurgery Fellowships–approved fellowship were identified, and the h and g indices of each of their surgeons were calculated. These were correlated with academic rank and compared with published literature on academic neurosurgical departments.
Seventy-two pediatric neurosurgeons had a mean h index of 16.6 and a mean g index of 29.5. Both indices increased with progressive academic rank. The rank-specific mean index for academic pediatric neurosurgeons was similar to that of neurosurgeons from academic departments in general.
Overall, the authors conclude that the h index metric is a reasonable measure of academic productivity in the pediatric neurosurgery arena that provides a robust measure of an individual's contribution to the pediatric neurosurgery literature. Like its counterpart in neurosurgery in general, the h index for pediatric neurosurgeons correlates with institutional rank. The h index calculation also reveals the productivity of the pediatric neurosurgeons to be on par with the productivity of neurosurgeons in general.
Brandon A. Sherrod, Rajiv R. Iyer, and John R. W. Kestle
Surgical options for managing hydrocephalus secondary to CNS tumors have traditionally included ventriculoperitoneal shunting (VPS) when tumor resection or medical management alone are ineffective. Endoscopic third ventriculostomy (ETV) has emerged as an attractive treatment strategy for tumor-associated hydrocephalus because it offers a lower risk of infection and hardware-related complications; however, relatively little has been written on the topic of ETV specifically for the treatment of tumor-associated hydrocephalus. Here, the authors reviewed the existing literature on the use of ETV in the treatment of tumor-associated hydrocephalus, focusing on the frequency of ETV use and the failure rates in patients with hydrocephalus secondary to CNS tumor.
The authors queried PubMed for the following terms: “endoscopic third ventriculostomy,” “tumor,” and “pediatric.” Papers with only adult populations, case reports, and papers published before the year 2000 were excluded. The authors analyzed the etiology of hydrocephalus and failure rates after ETV, and they compared failure rates of ETV with those of VPS where reported.
Thirty-two studies with data on pediatric patients undergoing ETV for tumor-related hydrocephalus were analyzed. Tumors, particularly in the posterior fossa, were reported as the etiology of hydrocephalus in 38.6% of all ETVs performed (984 of 2547 ETVs, range 29%–55%). The ETV failure rate in tumor-related hydrocephalus ranged from 6% to 38.6%, and in the largest studies analyzed (> 100 patients), the ETV failure rate ranged from 10% to 38.6%. The pooled ETV failure rate was 18.3% (199 failures after 1087 procedures). The mean or median follow-up for ETV failure assessment ranged from 6 months to 8 years in these studies. Only 5 studies directly compared ETV with VPS for tumor-associated hydrocephalus, and they reported mixed results in regard to failure rate and time to failure. Overall failure rates appear similar for ETV and VPS over time, and the risk of infection appears to be lower in those patients undergoing ETV. The literature is mixed regarding the need for routine ETV before resection for posterior fossa tumors with associated hydrocephalus.
Treatment of tumor-related hydrocephalus with ETV is common and is warranted in select pediatric patient populations. Failure rates are overall similar to those of VPS for tumor-associated hydrocephalus.
Antibiotic-impregnated external ventricular drains
John R. W. Kestle
John R. W. Kestle and Marion L. Walker
Previous reports suggest that adjustable valves may improve the survival of cerebrospinal fluid shunts or relieve shunt-related symptoms. To evaluate these claims, the authors conducted a prospective multicenter cohort study of children who underwent placement of Strata valves.
Patients undergoing initial shunt placement (Group 1) or shunt revision (Group 2) were treated using Strata valve shunt systems. Valves were adjustable to five performance level settings by using an externally applied magnet. The performance levels were checked using an externally applied hand tool and radiography. Patients were followed for 1 year or until they underwent shunt revision surgery.
Between March 2000 and February 2002, 315 patients were enrolled in the study. In Group 1 (201 patients) the common causes of hydrocephalus were myelomeningocele (16%), aqueductal stenosis (14%), and hemorrhage (14%). The overall 1-year shunt survival was 67%. Causes of shunt failure were obstruction (17%), overdrainage (1.5%), loculated ventricles (2%), and infection (10.6%). Patients in Group 2 (114 patients) were older and the causes of hydrocephalus were similar. Among patients in Group 2 the 1-year shunt survival was 71%.
There were 256 valve adjustments. Symptoms completely resolved (26%) or improved (37%) after 63% of adjustments. When symptoms improved or resolved, they did so within 24 hours in 89% of adjustments. Hand-tool and radiographic readings of valve settings were the same in 234 (98%) of 238 assessments.
The 1-year shunt survival for the Strata valve shunt system when used in initial shunt insertion procedures or shunt revisions was similar to those demonstrated for other valves. Symptom relief or improvement following adjustment was observed in 63% of patients. Hand-tool assessment of performance level settings reliably predicted radiographic assessments.