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Andrew S. Luksik, Tomas Garzon-Muvdi, Wuyang Yang, Judy Huang and George I. Jallo

OBJECTIVE

Intramedullary spinal cord tumors comprise 1%–10% of all childhood central nervous system neoplasms, with astrocytomas representing the most common subtype. Due to their rarity and poor prognosis, large population-based studies are needed to assess the epidemiology and survival risk factors associated with these tumors in the hope of improving outcome. The authors undertook this retrospective study to explore factors that may influence survival in pediatric patients with spinal cord astrocytomas.

METHODS

Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, a prospective cancer registry, the authors retrospectively assessed survival in histologically confirmed, primary spinal cord astrocytomas in patients 21 years of age and younger. Survival was described with Kaplan-Meyer curves, and a multivariate regression analysis was used to assess the association of several variables with survival while controlling for confounding variables.

RESULTS

This analysis of 348 cases showed that age (hazard ratio [HR] 1.05, 95% CI 1.01–1.09, p = 0.017), nonwhite race (HR 1.74, 95% CI 1.11–2.74, p = 0.014), high-grade tumor status (HR 14.67, 95% CI 6.69–32.14, p < 0.001), distant or invasive extension of the tumor (HR 2.37, 95% CI 1.02–5.49, p = 0.046), and radiation therapy (HR 3.74, 95% CI 2.18–6.41, p < 0.001) were associated with decreased survival. Partial resection (HR 0.37, 95% CI 0.16–0.83, p = 0.017) and gross-total resection (HR 0.39, 95% CI 0.16–0.95, p = 0.039) were associated with improved survival.

CONCLUSIONS

Younger age appears to be protective, while high-grade tumors have a much worse prognosis. Early diagnosis and access to surgery appears necessary for improving outcomes, while radiation therapy has an unclear role. There is still much to learn about this disease in the hope of curing children with the misfortune of having one of these rare tumors.

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Brendan F. Judy, Jordan W. Swanson, Wuyang Yang, Phillip B. Storm, Scott P. Bartlett, Jesse A. Taylor, Gregory G. Heuer and Shih-Shan Lang

OBJECTIVE

Evaluation of increased intracranial pressure (ICP) in the pediatric craniosynostosis population based solely on ophthalmological, clinical, and radiographic data is subjective, insensitive, and inconsistent. The aim of this study was to examine the intraoperative ICP before and after craniectomy in this patient population.

METHODS

The authors measured the ICP before and after craniectomy using a subdural ICP monitor in 45 children. They regulated end-tidal carbon dioxide and the monitoring site under general anesthesia to record consistent ICP readings.

RESULTS

The average age of the patient population was 29 months (range 3.8–180.5 months). Thirty-seven patients (82.2%) were undergoing initial craniosynostosis procedures. All craniosynostosis procedures were categorized as one of the following: frontoorbital advancement (n = 24), frontoorbital advancement with distraction osteogenesis (n = 1), posterior vault distraction osteogenesis (n = 10), and posterior vault reconstruction (n = 10). Nineteen of 45 patients (42.2%) had syndromic or multisuture craniosynostosis. The mean postcraniectomy ICP (8.8 mm Hg, range 2–18 mm Hg) was significantly lower than the precraniectomy ICP (16.5 mm Hg, range 6–35 mm Hg) (p < 0.001). Twenty-four patients (53%) had elevated ICP prior to craniectomy, defined as ≥ 15 mm Hg. Only 4 (8.9%) children had papilledema on preoperative funduscopic examination (sensitivity 17%, specificity 100%, negative predictive value 51%, and positive predictive value 100%). There were no significant differences in elevated precraniectomy ICP based on type of craniosynostosis (syndromic/multisuture or nonsyndromic) or age at the time of surgery. Patients undergoing initial surgery in the first 12 months of life were significantly less likely to have elevated precraniectomy ICP compared with patients older than 12 months (26.3% vs 73.1%, p = 0.005).

CONCLUSIONS

In this study, the authors report the largest cohort of syndromic and nonsyndromic craniosynostosis patients (n = 45) who underwent precraniectomy and postcraniectomy ICP evaluation. A craniectomy or completed craniotomy cuts for distractors effectively reduced ICP in 43/45 patients. The authors’ findings support the notion that papilledema on funduscopy is a highly specific, however poorly sensitive, indicator of increased ICP, and thus is not a reliable screening method. These findings indicate that even nonsyndromic patients with craniosynostosis are at risk for increased ICP. Furthermore, patients who present prior to 12 months of age appear less likely to have elevated ICP on presentation. Further studies with other noninvasive imaging of the retina may be useful as an adjunct tool for determining elevated ICP.

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Wuyang Yang, Heather Anderson-Keightly, Erick M. Westbroek, Justin M. Caplan, Xiaoming Rong, Alice L. Hung, Geoffrey P. Colby, Alexander L. Coon, Rafael J. Tamargo, Judy Huang and Edward S. Ahn

OBJECTIVE

Compared with the general population, the specific natural history of arteriovenous malformations (AVMs) in pediatric patients is less well understood. Furthermore, few pediatric studies have compared posttreatment hemorrhagic risk and functional outcome across different treatment modalities. The objective of this study was to elucidate these points.

METHODS

The authors retrospectively reviewed all pediatric patients with AVMs evaluated at their institution between 1990 and 2013. The AVM natural history was represented by hemorrhagic risk during the observation period. For treated patients, the observation period was defined as the interval between diagnosis and treatment. Posttreatment hemorrhagic risk and functional outcomes were also assessed.

RESULTS

A total of 124 pediatric patients with AVMs were evaluated, and 90 patients (72.6%) were retained through follow-up. The average patient age was 13.3 ± 3.8 years, with a mean follow-up period of 9.95 years. The overall AVM obliteration rate was 59.7%. Radiosurgery had an obliteration rate of 49.0%. Thirteen patients were managed conservatively. Four patients under observation hemorrhaged during a total interval of 429.4 patient-years, translating to an annual risk of 0.9%. Posttreatment hemorrhagic risk by treatment modalities were categorized as follows: surgery ± embolization (0.0%), radiosurgery ± embolization (0.8%), embolization alone (2.8%), surgery + radiosurgery ± embolization (3.5%), and observation (0.8%). A significantly higher risk of posttreatment hemorrhage was observed for patients with hemorrhagic presentation (p = 0.043) in multivariate analysis. Seizure presentation, frontal lobe location, nonheadache presentation, and treatment modality were significantly associated with increased risk of poor functional outcomes.

CONCLUSIONS

In this study of pediatric patients with AVMs, the natural history of hemorrhage was relatively low at 0.9%. Resection remained the optimal management for hemorrhage control and functional outcome perseverance in these pediatric patients with AVMs. AVM obliteration is a valid treatment goal, especially for patients with ruptured presentation, to prevent further hemorrhages later in life.

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Wuyang Yang, Risheng Xu, Jose L. Porras, Clifford M. Takemoto, Syed Khalid, Tomas Garzon-Muvdi, Justin M. Caplan, Geoffrey P. Colby, Alexander L. Coon, Rafael J. Tamargo, Judy Huang and Edward S. Ahn

OBJECTIVE

Sickle cell disease (SCD) in combination with moyamoya syndrome (MMS) represents a rare complication of SCD, with potentially devastating neurological outcomes. The effectiveness of surgical revascularization in this patient population is currently unclear. The authors’ aim was to determine the effectiveness of surgical intervention in their series of SCD-MMS patients by comparing stroke recurrence in those undergoing revascularization and those undergoing conservative transfusion therapy.

METHODS

The authors performed a retrospective chart review of patients with MMS who were seen at the Johns Hopkins Medical Institution between 1990 and 2013. Pediatric patients (age < 18 years) with confirmed diagnoses of SCD and MMS were included. Intracranial stroke occurrence during the follow-up period was compared between surgically and conservatively managed patients.

RESULTS

A total of 15 pediatric SCD-MMS patients (28 affected hemispheres) were included in this study, and all were African American. Seven patients (12 hemispheres) were treated with indirect surgical revascularization. The average age at MMS diagnosis was 9.0 ± 4.0 years, and 9 patients (60.0%) were female. Fourteen patients (93.3%) had strokes before diagnosis of MMS, with an average age at first stroke of 6.6 ± 3.9 years. During an average follow-up period of 11.6 years, 4 patients in the conservative treatment group experienced strokes in 5 hemispheres, whereas no patient undergoing the revascularization procedure had any strokes at follow-up (p = 0.029). Three patients experienced immediate postoperative transient ischemic attacks, but all recovered without subsequent strokes.

CONCLUSIONS

Indirect revascularization is suggested as a safe and effective alternative to the best medical therapy alone in patients with SCD-MMS. High-risk patients managed on a regimen of chronic transfusion should be considered for indirect revascularization to maximize the effect of stroke prevention.