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Lucy He, Stephen Gannon, Chevis N. Shannon, Brandon G. Rocque, Jay Riva-Cambrin and Robert P. Naftel

OBJECTIVE

The success of endoscopic third ventriculostomy with choroid plexus cauterization may have associations with age, etiology of hydrocephalus, previous shunting, cisternal scarring, and possibly aqueduct patency. This study aimed to measure interrater reliability among surgeons in identifying cisternal scarring and aqueduct patency.

METHODS

Using published definitions of cistern scarring and aqueduct patency, 7 neuroendoscopists with training from Dr. Warf in Uganda and 7 neuroendoscopists who were not trained by Dr. Warf rated cistern status from 30 operative videos and aqueduct patency from 26 operative videos. Interrater agreement was calculated using Fleiss' kappa coefficient (κ). Fisher's 2-tailed exact test was used to identify differences in the rates of agreement between the Warf-trained and nontrained groups compared with Dr. Warf's reference answer.

RESULTS

Aqueduct status, among all raters, showed substantial agreement with κ = 0.663 (confidence interval [CI] 0.626–0.701); within the trained group and nontrained groups, there was substantial agreement with κ = 0.677 (CI 0.593–0.761) and κ = 0.631 (CI 0.547–0.715), respectively. The identification of cistern scarring was less reliable, with moderate agreement among all raters with κ = 0.536 (CI 0.501–0.571); within the trained group and nontrained groups, there was moderate agreement with κ = 0.555 (CI 0.477–0.633) and κ = 0.542 (CI 0.464–0.620), respectively. There was no statistically significant difference in the amount of agreement between groups compared with Dr. Warf's reference.

CONCLUSIONS

Regardless of training with Dr. Warf, all neuroendoscopists could identify scarred cisterns and aqueduct patency with similar reliability, emphasizing the strength of the published definitions. This makes the identification of this risk factor for failure generalizable for surgical decision making and research studies.

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Travis R. Ladner, Ashly C. Westrick, John C. Wellons III and Chevis N. Shannon

OBJECT

The purpose of this study was to design and validate a patient-reported health-related quality of life (HRQOL) instrument for pediatric Chiari Type I malformation (CM-I), the Chiari Health Index for Pediatrics (CHIP).

METHODS

The CHIP has 45 items with 4 components making up 2 domain scores, physical (pain frequency, pain severity, nonpain symptoms) and psychosocial; physical and psychosocial scores are combined to create an overall HRQOL score. Increasing scores (0 to 1) represent increasing HRQOL. Fifty-five patients with CM-I (mean age 12 ± 4 years, 53% male) were enrolled and completed the CHIP and Health Utilities Index Mark 3 (HUI3). Twenty-five healthy controls (mean age 11.9 ± 4 years, 40% male) also completed the CHIP. CHIP scores were compared between these groups via the Mann-Whitney U-test. For CHIP discriminative function, subscore versus presence of CM-I was compared via receiver operating characteristic curve analysis. CHIP scores in the CM-I group were stratified by symptomatology (asymptomatic, headaches, and paresthesias) and compared via Kruskal-Wallis test with Mann-Whitney U-test with Bonferroni correction (p < 0.0167). CHIP was compared with HUI3 (Health Utilities Index Mark 3) via univariate and multivariate linear regression.

RESULTS

CHIP physical and psychosocial subscores were, respectively, 24% and 18% lower in CM-I patients than in controls (p < 0.001); the overall HRQOL score was 23% lower as well (p < 0.001). The area under the curve (AUC) for CHIP physical subscore versus presence of CM-I was 0.809. CHIP physical subscore varied significantly with symptomatology (p = 0.001) and HUI3 pain-related quality of life (R2 = 0.311, p < 0.001). The AUC for CHIP psychosocial subscore versus presence of CM-I was 0.754. CHIP psychosocial subscore varied significantly with HUI3 cognitive- (R2 = 0.324, p < 0.001) and emotion-related (R2 = 0.155, p = 0.003) quality of life. The AUC for CHIP HRQOL versus presence of CM-I was 0.820. Overall CHIP HRQOL score varied significantly with symptomatology (p = 0.001) and HUI3 multiattribute composite HRQOL score (R2 = 0.440, p < 0.001).

CONCLUSIONS

The CHIP is a patient-reported, CM-I-specific HRQOL instrument, with construct validity in assessing pain-, cognitive-, and emotion-related quality of life, as well as symptomatic features unique to CM-I. It holds promise as a discriminative HRQOL index in CM-I outcomes assessment.

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Michael C. Dewan, Jaims Lim, Chevis N. Shannon and John C. Wellons III

OBJECTIVE

Up to one-third of patients with a posterior fossa brain tumor (PFBT) will experience persistent hydrocephalus mandating permanent CSF diversion. The optimal hydrocephalus treatment modality is unknown; the authors sought to compare the durability between endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt (VPS) therapy in the pediatric population.

METHODS

The authors conducted a systematic review of articles indexed in PubMed between 1986 and 2016 describing ETV and/or VPS treatment success/failure and time-to-failure rate in patients < 19 years of age with hydrocephalus related to a PFBT. Additionally, the authors conducted a retrospective review of their institutional series of PFBT patients requiring CSF diversion. Patient data from the systematic review and from the institutional series were aggregated and a time-to-failure analysis was performed comparing ETV and VPS using the Kaplan-Meier method.

RESULTS

A total of 408 patients were included from 12 studies and the authors' institutional series: 284 who underwent ETV and 124 who underwent VPS placement. The analysis included uncontrolled studies with variable method and timing of CSF diversion and were subject to surgeon bias. No significant differences between cohorts were observed with regard to age, sex, tumor grade or histology, metastatic status, or extent of resection. The cumulative failure rate of ETV was 21%, whereas that of VPS surgery was 29% (p = 0.105). The median time to failure was earlier for ETV than for VPS surgery (0.82 [IQR 0.2–1.8] vs 4.7 months [IQR 0.3–5.7], p = 0.03). Initially the ETV survival curve dropped sharply and then stabilized around 2 months. The VPS curve fell gradually but eventually crossed below the ETV curve at 5.7 months. Overall, a significant survival advantage was not demonstrated for one procedure over the other (p = 0.21, log-rank). However, postoperative complications were higher following VPS (31%) than ETV (17%) (p = 0.012).

CONCLUSIONS

ETV failure occurred sooner than VPS failure, but long-term treatment durability may be higher for ETV. Complications occurred more commonly with VPS than with ETV. Limited clinical conclusions are drawn using this methodology; the optimal treatment for PFBT-related hydrocephalus warrants investigation through prospective studies.

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Travis R. Ladner, Michael C. Dewan, Matthew A. Day, Chevis N. Shannon, Luke Tomycz, Noel Tulipan and John C. Wellons III

OBJECT

Osseous anomalies of the craniocervical junction are hypothesized to precipitate the hindbrain herniation observed in Chiari I malformation (CM-I). Previous work by Tubbs et al. showed that posterior angulation of the odontoid process is more prevalent in children with CM-I than in healthy controls. The present study is an external validation of that report. The goals of our study were 3-fold: 1) to externally validate the results of Tubbs et al. in a different patient population; 2) to compare how morphometric parameters vary with age, sex, and symptomatology; and 3) to develop a correlative model for tonsillar ectopia in CM-I based on these measurements.

METHODS

The authors performed a retrospective review of 119 patients who underwent posterior fossa decompression with duraplasty at the Monroe Carell Jr. Children’s Hospital at Vanderbilt University; 78 of these patients had imaging available for review. Demographic and clinical variables were collected. A neuroradiologist retrospectively evaluated preoperative MRI examinations in these 78 patients and recorded the following measurements: McRae line length; obex displacement length; odontoid process parameters (height, angle of retroflexion, and angle of retroversion); perpendicular distance to the basion-C2 line (pB–C2 line); length of cerebellar tonsillar ectopia; caudal extent of the cerebellar tonsils; and presence, location, and size of syringomyelia. Odontoid retroflexion grade was classified as Grade 0, > 90°; Grade I,85°–89°; Grade II, 80°–84°; and Grade III, < 80°. Age groups were defined as 0–6 years, 7–12 years, and 13–17 years at the time of surgery. Univariate and multivariate linear regression analyses, Kruskal-Wallis 1-way ANOVA, and Fisher’s exact test were performed to assess the relationship between age, sex, and symptomatology with these craniometric variables.

RESULTS

The prevalence of posterior odontoid angulation was 81%, which is almost identical to that in the previous report (84%). With increasing age, the odontoid height (p < 0.001) and pB–C2 length (p < 0.001) increased, while the odontoid process became more posteriorly inclined (p = 0.010). The pB–C2 line was significantly longer in girls (p = 0.006). These measurements did not significantly correlate with symptomatology. Length of tonsillar ectopia in pediatric CM-I correlated with an enlarged foramen magnum (p = 0.023), increasing obex displacement (p = 0.020), and increasing odontoid retroflexion (p < 0.001).

CONCLUSIONS

Anomalous bony development of the craniocervical junction is a consistent feature of CM-I in children. The authors found that the population at their center was characterized by posterior angulation of the odontoid process in 81% of cases, similar to findings by Tubbs et al. (84%). The odontoid process appeared to lengthen and become more posteriorly inclined with age. Increased tonsillar ectopia was associated with more posterior odontoid angulation, a widened foramen magnum, and an inferiorly displaced obex.

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Andrew T. Hale, David P. Stonko, Jaims Lim, Oscar D. Guillamondegui, Chevis N. Shannon and Mayur B. Patel

OBJECTIVE

Pediatric traumatic brain injury (TBI) is common, but not all injuries require hospitalization. A computational tool for ruling in patients who will have a clinically relevant TBI (CRTBI) would be valuable, providing an evidence-based way to safely discharge children who are at low risk for a CRTBI. The authors hypothesized that an artificial neural network (ANN) trained on clinical and radiologist-interpreted imaging metrics could provide a tool for identifying patients likely to suffer from a CRTBI.

METHODS

The authors used the prospectively collected, publicly available, multicenter Pediatric Emergency Care Applied Research Network (PECARN) TBI data set. All patients under the age of 18 years with TBI and admission head CT imaging data were included. The authors constructed an ANN using clinical and radiologist-interpreted imaging metrics in order to predict a CRTBI, as previously defined by PECARN: 1) neurosurgical procedure, 2) intubation > 24 hours as direct result of the head trauma, 3) hospitalization ≥ 48 hours and evidence of TBI on a CT scan, or 4) death due to TBI.

RESULTS

Among 12,902 patients included in this study, 480 were diagnosed with CRTBI. The authors’ ANN had a sensitivity of 99.73% with precision of 98.19%, accuracy of 97.98%, negative predictive value of 91.23%, false-negative rate of 0.0027%, and specificity for CRTBI of 60.47%. The area under the receiver operating characteristic curve was 0.9907.

CONCLUSIONS

The authors are the first to utilize artificial intelligence to predict a CRTBI in a clinically meaningful manner, using radiologist-interpreted CT information, in order to identify pediatric patients likely to suffer from a CRTBI. This proof-of-concept study lays the groundwork for future studies incorporating iterations of this algorithm directly into the electronic medical record for real-time, data-driven predictive assistance to physicians.

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Travis R. Ladner, Michael C. Dewan, Matthew A. Day, Chevis N. Shannon, Luke Tomycz, Noel Tulipan and John C. Wellons III

OBJECT

The clinical significance of radiological measurements of the craniocervical junction in pediatric Chiari I malformation (CM-I) is yet to be fully established across the field. The authors examined their institutional experience with the pB–C2 line (drawn perpendicular to a line drawn between the basion and the posterior aspect of the C-2 vertebral body, at the most posterior extent of the odontoid process at the dural interface). The pB–C2 line is a measure of ventral canal encroachment, and its relationship with symptomatology and syringomyelia in pediatric CM-I was assessed.

METHODS

The authors performed a retrospective review of 119 patients at the Monroe Carell Jr. Children's Hospital at Vanderbilt University who underwent posterior fossa decompression with duraplasty, 78 of whom had imaging for review. A neuroradiologist retrospectively evaluated preoperative and postoperative MRI examinations performed in these 78 patients, measuring the pB–C2 line length and documenting syringomyelia. The pB–C2 line length was divided into Grade 0 (< 3 mm) and Grade I (≥ 3 mm). Statistical analysis was performed using the t-test for continuous variables and Fisher's exact test analysis for categorical variables. Multivariate logistic and linear regression analyses were performed to assess the relationship between pB–C2 line grade and clinical variables found significant on univariate analysis, controlling for age and sex.

RESULTS

The mean patient age was 8.5 years, and the mean follow-up duration was 2.4 years. The mean pB–C2 line length was 3.5 mm (SD 2 mm), ranging from 0 to 10 mm. Overall, 65.4% of patients had a Grade I pB–C2 line. Patients with Grade I pB–C2 lines were 51% more likely to have a syrinx than those with Grade 0 pB–C2 lines (RR 1.513 [95% CI 1.024–2.90], p = 0.021) and, when present, had greater syrinx reduction (3.6 mm vs 0.2 mm, p = 0.002). Although there was no preoperative difference in headache incidence, postoperatively patients with Grade I pB–C2 lines were 69% more likely to have headache reduction than those with Grade 0 pB–C2 lines (RR 1.686 [95% CI 1.035–2.747], p = 0.009). After controlling for age and sex, pB–C2 line grade remained an independent correlate of headache improvement and syrinx reduction.

CONCLUSIONS

Ventral canal encroachment may explain the symptomatology of select patients with CM-I. The clinical findings presented suggest that patients with Grade I pB–C lines2, with increased ventral canal obstruction, may experience a higher likelihood of syrinx reduction and headache resolution from decompressive surgery with duraplasty than those with Grade 0 pB–C2 lines.

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Emily W. Chan, Stephen R. Gannon, Chevis N. Shannon, Jeffrey E. Martus, Gregory A. Mencio and Christopher M. Bonfield

OBJECTIVE

Adolescent idiopathic scoliosis (AIS), the most common type of scoliosis, often presents immediately prior to a woman’s childbearing years; however, research investigating the impact of AIS on women’s health, particularly pregnancy delivery outcomes, is sparse, with existing literature reporting mixed findings. Similarly limited are studies examining the change in scoliotic curve during or after pregnancy. Therefore, this study aims to determine 1) the impact of scoliotic curvature on obstetric complications (preterm births, induction of labor, and urgent/emergency caesarean section delivery), 2) regional anesthetic decision making and success during delivery for these patients, and 3) the effect of pregnancy on curve progression.

METHODS

Records of all pregnant patients diagnosed with AIS at the authors’ institution who delivered between January 2002 and September 2016 were retrospectively reviewed. Demographic information, pre- and postpartum radiographic Cobb angles, and clinical data for each pregnancy and delivery were recorded and analyzed. The Wilcoxon rank-sum test and the Wilcoxon signed-rank test were used for statistical analyses.

RESULTS

Fifty-nine patients (84 deliveries) were included; 14 patients had undergone prior posterior spinal fusion. The median age at AIS diagnosis was 15.2 years, and the median age at delivery was 21.8 years. Overall, the median major Cobb angle prior to the first pregnancy was 25° (IQR 15°–40°). Most births were by spontaneous vaginal delivery (n = 45; 54%); elective caesarean section was performed in 17 deliveries (20%). Obstetric complications included preterm birth (n = 18; 21.4%), induction of labor (n = 20; 23.8%), and urgent/emergency caesarean section (n = 12; 14.0%); none were associated with severity of scoliosis curve or prior spinal fusion. Attempts at spinal anesthesia were successful 99% of the time (70/71 deliveries), even among the patients who had undergone prior spinal fusion (n = 13). There were only 3 instances of provider refusal to administer spinal anesthesia. In the subset of 11 patients who underwent postpartum scoliosis radiography, there was no statistically significant change in curve magnitude either during or immediately after pregnancy.

CONCLUSIONS

The results of this study suggest that there was no effect of the severity of scoliosis on delivery complications or regional anesthetic decision making in pregnant patients with AIS. Moreover, scoliosis was not observed to progress significantly during or immediately after pregnancy. Larger prospective studies are needed to further investigate these outcomes, the findings of which can guide the prenatal education and counseling of pregnant patients with AIS.

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Christopher M. Bonfield, Rachel Pellegrino, Jillian Berkman, Robert P. Naftel, Chevis N. Shannon and John C. Wellons III

OBJECTIVE

Both the American Association of Neurological Surgeons/Congress of Neurological Surgeons Joint Section on Pediatric Neurological Surgery (AANS/CNS Pediatric Section) and the International Society for Pediatric Neurosurgery (ISPN) annual meetings provide a platform for pediatric neurosurgeons to present, discuss, and disseminate current academic research. An ultimate goal of these meetings is to publish presented results in peer-reviewed journals. The purpose of the present study was to investigate the publication rates of oral presentations from the 2009, 2010, and 2011 AANS/CNS Pediatric Section and ISPN annual meetings in peer-reviewed journals.

METHODS

All oral presentations from the 2009, 2010, and 2011 AANS/CNS Pediatric Section and ISPN annual meetings were reviewed. Abstracts were obtained from the AANS/CNS Pediatric Section and ISPN conference proceedings, which are available online. Author and title information were used to search PubMed to identify those abstracts that had progressed to publication in peer-reviewed journals. The title of the journal, year of the publication, and authors’ country of origin were also recorded.

RESULTS

Overall, 60.6% of the presented oral abstracts from the AANS/CNS Pediatric Section meetings progressed to publication in peer-reviewed journals, as compared with 40.6% of the ISPN presented abstracts (p = 0.0001). The journals in which the AANS/CNS Pediatric Section abstract-based publications most commonly appeared were Journal of Neurosurgery: Pediatrics (52%), Child’s Nervous System (11%), and Journal of Neurosurgery (8%). The ISPN abstracts most often appeared in the journals Child’s Nervous System (29%), Journal of Neurosurgery: Pediatrics (14%), and Neurosurgery (9%). Overall, more than 90% of the abstract-based articles were published within 4 years after presentation of the abstracts on which they were based.

CONCLUSIONS

Oral abstract presentations at two annual pediatric neurosurgery meetings have publication rates in peer-reviewed journal comparable to those for oral abstracts at other national and international neurosurgery meetings. The vast majority of abstract-based papers are published within 4 years of the meeting at which the abstract was presented; however, the AANS/CNS Pediatric Section abstracts are published at a significantly higher rate than ISPN abstracts, which could indicate the different meeting sizes, research goals, and resources of US authors compared with those of authors from other countries.

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Robert P. Naftel, Nicole A. Safiano, Michael I. Falola, Chevis N. Shannon, John C. Wellons III and James M. Johnston Jr.

Object

The Internet and social media are powerful disseminators of medical information, providing new portals for patient care. The authors of this study evaluated current technology hardware, Internet, and social media use and their socioeconomic relationships among caregivers of children with hydrocephalus.

Methods

A written survey was completed in the neurosurgical clinics at the University of Alabama at Birmingham by 300 parents of children with shunted hydrocephalus between October 26, 2010, and July 26, 2011.

Results

Computer use (94.6%), Internet use (91.7%), smartphone use (56.9%), and Internet research on hydrocephalus (81.9%) were prevalent. However, for each of these four utilizations there was significantly lower access by caregivers of minority races (p = 0.04, 0.03, 0.002, and < 0.0001, respectively), lower income (p = 0.02, 0.01, < 0.0001, and < 0.0001, respectively), and lower level of education (p = 0.001, 0.002, < 0.0001, and 0.001, respectively). Personal use of social media was prevalent (95.1% of all Internet users) with use being more prevalent among less-educated than higher-educated caregivers (p = 0.017). Hydrocephalus-related social media use (59.5% of Internet users) was not associated with socioeconomic factors. For hydrocephalus education on the Internet, caregivers chose information websites such as Wikipedia or the Hydrocephalus Association as preferred platforms; these preferences were followed by use of social media websites. Facebook and YouTube were the preferred social media platforms for personal and hydrocephalus-related use. Parents indicate moderate skepticism about the trustworthiness of the Internet; only 21.7% always trust the online sources. Most parents (89.8%) say that they would visit neurosurgeon-recommended websites. Of Internet-using caregivers, 28.6% use the Internet or social media to find hydrocephalus support groups, and 34.8% have used the Internet to communicate with other caregivers who have children with similar conditions.

Conclusions

Technology hardware, the Internet, and social media are widely used with some skepticism by parents of children with shunted hydrocephalus. Caregivers are interested in physician-recommended Internet resources. Socioeconomic factors including race, income, and level of education reveal a disparity in access to some of these resources, although all groups have relatively high use. Unlike typical technology use, social media use is breaking down the digital divide among ethnic and socioeconomic groups.

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Amber S. Gordon, Ashly C. Westrick, Michael I. Falola, Chevis N. Shannon, Beverly C. Walters and Winfield S. Fisher

Object

This study was undertaken to assess the reliability of observations of postoperative photographs in assigning House-Brackmann scores as outcome measures for patients following resection of vestibular schwannomas.

Methods

Forty pictures of differing facial expressions typically elicited from patients for assigning House-Brackmann scores were individually evaluated by neurosurgery residents and faculty members at the University of Alabama at Birmingham; a score was assigned to each picture by the individual raters. The interrater reliability was measured using the Spearman correlation coefficient, Kendall coefficient of concordance, and kappa statistic; internal consistency was calculated using the Cronbach alpha reliability estimate.

Results

The Spearman correlation coefficients showed strong positive association among raters, with a range of values of 0.66 to 0.90. Internal consistency measured by the Cronbach alpha coefficient was excellent (α = 0.97). The Kendall coefficient of concordance for the ordinal grades suggested a substantial degree of agreement among the raters (w = 0.76, p < 0.001).

Conclusions

Static postoperative photographs are a reliable outcome measure for determining facial nerve function after vestibular schwannoma resection and may serve as a surrogate for the dynamic patient interview.