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Timothy W. Vogel, Biji Bahuleyan, Shenandoah Robinson and Alan R. Cohen


Hydrocephalus remains a major public health problem. Conventional treatment has relied on extracranial shunting of CSF to another systemic site, but this approach is associated with a high rate of complications. Endoscopic third ventriculostomy (ETV) is a novel treatment for select forms of hydrocephalus that can eliminate the need for implantation of a lifelong ventricular shunt system. However, the indications for ETV are contested and its long-term effectiveness is not well established.


The authors selected 100 consecutive patients who underwent ETV for hydrocephalus beginning in 1994. Patients were enrolled and treated at a single institution by a single surgeon. The primary outcome was success of ETV, with success defined as no need for subsequent surgery for hydrocephalus.


Ninety-five patients satisfied the inclusion criteria. The mean follow-up period was 5.1 years (median 4.7 years) with follow-up data available for as long as 17 years. Patients commonly presented with headache (85%), ataxia (34%), emesis (29%), and changes in vision (27%). The success rate for ETV was 75%. Twenty-one patients (22%) in the series had malfunctioning shunts preoperatively and 13 (62%) were successfully treated with ETV. Preoperative inferior bowing of the third ventricle floor on MRI was significantly associated with ETV success (p < 0.05).


Endoscopic third ventriculostomy is an effective and durable treatment for select patients with hydrocephalus. When successful, the procedure eliminates the lifelong complications associated with implanted ventricular shunts.

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Timothy C. Ryken, Robert A. Robinson and John C. VanGilder

✓ Subependymomas are unusual tumors believed to arise from the bipotential subependymal cell. Previous reports of familial occurrence of subependymoma have involved monozygous twins and siblings. The authors describe the first reported occurrence of fourth ventricular subependymoma in a father and son, suggesting the possibility of direct inheritance.

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Hormuzdiyar H. Dasenbrock, Timothy R. Smith and Shenandoah Robinson


The goal of this study was to evaluate clinical predictors of abnormal preoperative laboratory values in pediatric neurosurgical patients.


Data obtained in children who underwent a neurosurgical operation were extracted from the prospective National Surgical Quality Improvement Program–Pediatrics (NSQIP-P, 2012–2013) registry. Multivariable logistic regression evaluated predictors of preoperative laboratory values that might require further evaluation (white blood cell count < 2000/μl, hematocrit < 24%, platelet count < 100,000/μl, international normalized ratio > 1.4, or partial thromboplastin time > 45 seconds) or a preoperative transfusion (within 48 hours prior to surgery). Variables screened included patient demographics; American Society of Anesthesiologists (ASA) physical designation classification; comorbidities; recent steroid use, chemotherapy, or radiation therapy; and admission type. Predictive score validation was performed using the NSQIP-P 2014 data.


Of the 6556 patients aged greater than 2 years, 68.9% (n = 5089) underwent laboratory testing, but only 1.9% (n = 125) had a critical laboratory value. Predictors of a laboratory abnormality were ASA class III–V; diabetes mellitus; hematological, hypothrombotic, or oncological comorbidities; nutritional support; recent chemotherapy; systemic inflammatory response syndrome; and a nonelective hospital admission. These 9 variables were used to create a predictive score, with a single point assigned for each predictor. The prevalence of critical values in the validation population (NSQIP-P 2014) of patients greater than 2 years of age was 0.3% with a score of 0, 1.0% in those with a score of 1, 1.6% in those with a score of 2, and 6.2% in those with a score ≥ 3. Higher score was predictive of a critical value (OR 2.33, 95% CI 1.91–2.83, p < 0.001, C-statistic 0.76) and with the requirement of a perioperative transfusion (intraoperatively or within 72 hours postoperatively; OR 1.42, 95% CI 1.22–1.67, p < 0.001) in the validation population. Moreover, when the same score was applied to children aged 2 years or younger, a greater score was predictive of a critical value (OR 2.47, 95% CI 2.15–2.84, p < 0.001, C-statistic 0.76).


Critical laboratory values in pediatric neurosurgical patients are largely predicted by clinical characteristics, and abnormal preoperative laboratory results are rare in patients older than 2 years of age without comorbidities who are undergoing elective surgery. The NSQIP-P critical preoperative laboratory value scale is proposed to indicate patients with the highest odds of an abnormal value. The scale can assist with triaging preoperative testing based on the surgical risk, as determined by the treating surgeon and anesthesiologist.

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Timothy W. Vogel, Calvin S. Carter, Kingsley Abode-Iyamah, Qihong Zhang and Shenandoah Robinson

Neural tube defects (NTDs) are a set of disorders that occur from perturbation of normal neural development. They occur in open or closed forms anywhere along the craniospinal axis and often result from a complex interaction between environmental and genetic factors. One burgeoning area of genetics research is the effect of cilia signaling on the developing neural tube and how the disruption of primary cilia leads to the development of NTDs. Recent progress has implicated the hedgehog (Hh), wingless-type integration site family (Wnt), and planar cell polarity (PCP) pathways in primary cilia as involved in normal neural tube patterning. A set of disorders involving cilia function, known as ciliopathies, offers insight into abnormal neural development. In this article, the authors discuss the common ciliopathies, such as Meckel-Gruber and Joubert syndromes, that are associated with NTDs, and review cilia-related signaling cascades responsible for mammalian neural tube development. Understanding the contribution of cilia in the formation of NTDs may provide greater insight into this common set of pediatric neurological disorders.

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Oral Presentations

2010 AANS Annual Meeting Philadelphia, Pennsylvania May 1–5, 2010