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Neurosurgical Treatment and Outcome of Pediatric Skull Base Lesions: A Case Series and Review of the Literature. CHILDREN (BASEL, SWITZERLAND) 2023; 10:children10020216. [PMID: 36832345 PMCID: PMC9954611 DOI: 10.3390/children10020216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 01/22/2023] [Accepted: 01/24/2023] [Indexed: 01/27/2023]
Abstract
INTRODUCTION Pediatric skull base lesions occur rarely and are of various etiologies. Traditionally, open craniotomy has been the treatment of choice; however, nowadays, endoscopic approaches are increasingly applied. In this retrospective case series, we describe our experience in treating pediatric skull base lesions and provide a systematic overview of the literature on the treatment and outcome of pediatric skull base lesions. METHODS We conducted a retrospective data collection of all pediatric patients (<18 years) treated for a skull base lesion at the Division of Pediatric Neurosurgery, University Children's Hospital Basel, Switzerland, between 2015 and 2021. Descriptive statistics and a systematic review of the available literature were additionally conducted. RESULTS We included 17 patients with a mean age of 8.92 (±5.76) years and nine males (52.9%). The most common entity was sellar pathologies (n = 8 47.1%), with craniopharyngioma being the most common pathology (n = 4, 23.5%). Endoscopic approaches, either endonasal transsphenoidal or transventricular, were used in nine (52.9%) cases. Six patients (35.3%) suffered from transient postoperative complications, while in none of the patients these were permanent. Of the nine (52.9%) patients with preoperative deficits, two (11.8%) showed complete recovery and one (5.9%) partial recovery after surgery. After screening 363 articles, we included 16 studies with a total of 807 patients for the systematic review. The most common pathology reported in the literature confirmed our finding of craniopharyngioma (n = 142, 18.0%). The mean PFS amongst all the studies included was 37.73 (95% CI [36.2, 39.2]) months, and the overall weighted complication rate was 40% (95% CI [0.28 to 0.53] with a permanent complication rate of 15% (95% CI [0.08 to 0.27]. Only one study reported an overall survival of their cohort of 68% at five years. CONCLUSION This study highlights the rarity and heterogeneity of skull base lesions in the pediatric population. While these pathologies are often benign, achieving GTR is challenging due to the deep localization of the lesions and eloquent adjacent structures, leading to high complication rates. Therefore, skull base lesions in children require an experienced multidisciplinary team to provide optimal care.
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Foo MI, Nicol K, Murakami JW. Skull base chondroblastoma with aneurysmal bone cyst-like changes treated with percutaneous radiofrequency ablation and doxycycline sclerotherapy: illustrative case. JOURNAL OF NEUROSURGERY. CASE LESSONS 2022; 4:CASE22436. [PMID: 36536526 PMCID: PMC9764370 DOI: 10.3171/case22436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 11/10/2022] [Indexed: 12/23/2022]
Abstract
BACKGROUND Chondroblastomas (CBs) are rare benign bone tumors that are often difficult to treat because of their locations. CBs can be even more challenging to successfully manage when they present alongside aneurysmal bone cyst (ABC)-like changes. To minimize operative morbidity, especially in hard-to-reach lesions, percutaneous approaches for both lesions have been individually described. We present a skull base CB with associated ABC-like changes treated by combining two different previously described percutaneous modalities. OBSERVATIONS The authors report successful percutaneous treatment of a skull base CB with adjacent ABC-like changes in a 17-year-old male. The CB was treated with radiofrequency ablation (RFA) and the adjacent ABC area with doxycycline sclerotherapy. After 3 years of follow-up, there has been no clinical or radiological evidence of recurrence. LESSONS CBs occur in the skull base and, as elsewhere in the body, can be associated with ABC-like changes. Successful percutaneous treatment of such a CB with ABC-like changes is possible by combining previously described techniques of RFA and doxycycline sclerotherapy.
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Affiliation(s)
| | - Kathleen Nicol
- Pathology, Nationwide Children’s Hospital, Columbus, Ohio
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Ballestero MFM, de Souza SNF, Pacheco Neto RC, Gondim GGP, Valera ET, Dos Reis MBF, Colli BO, de Oliveira RS. Pediatric Skull Base Tumors: A Management Challenge. J Pediatr Neurosci 2021; 16:35-43. [PMID: 34316306 PMCID: PMC8276951 DOI: 10.4103/jpn.jpn_56_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/29/2020] [Accepted: 08/17/2020] [Indexed: 12/29/2022] Open
Abstract
Context Skull base tumors are varied in children and are particularly challenging to pediatric neurosurgeons, with few papers in the literature describing the evolution, complications, and outcome. The authors evaluated long-term outcomes in children submitted to skull base tumor surgery and performed a literature review. Aims The aim of this study was to analyze surgical results, complications, and outcomes, on comparison with previous publications. Materials and Methods A retrospective analysis of children undergoing surgery at a single institution between 2000 and 2018 for lesions of the cranial base was carried out. In addition, a literature review was carried out describing a total of 115 children operated on for skull base tumors. Statistical Analysis Chi-squared and Fisher's exact tests were performed to compare the distribution of categorical variables and a nonparametric Mann-Whitney U test was used to perform intergroup comparisons of continuous variables. Results Seventeen children ranging in age from 8 months to 17 years (mean, 10.9 years) underwent skull base approaches. Tumor types included schwannoma, meningioma, chondroid chordoma, mature teratoma, epidermoid cyst, hemangiopericytoma, rhabdomyosarcoma, myofibroblastic inflammatory tumor, fibromyxoid sarcoma, Crooke's cell adenoma, ossifying fibroma, osteoblastoma, nasopharyngeal angiofibroma and Ewing's sarcoma. Gross total resection was achieved in 6 patients (35.3%), 12 patients (70.6%) had benign histology, and 5 patients (29.4%) had a malignant tumor. Transient postoperative cerebrospinal fluid leak affected only one patient. Thirteen children (76.4%) had a residual neurological deficit at last follow-up evaluation. Three (17.6%) surviving patients received adjuvant therapy. The rate of recurrence or lesion progression was 17.6%. Conclusions Skull base tumors in children present a therapeutic challenge because of their unique pathological composition and can lead to considerable morbidity and mortality in pediatric age.
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Affiliation(s)
- Matheus F M Ballestero
- Department of Medicine, Federal University of São Carlos, São Carlos, Brazil.,Division of Neurosurgery, Department of Surgery and Anatomy, University Hospital of Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Stephanie N F de Souza
- Division of Neurosurgery, Department of Surgery and Anatomy, University Hospital of Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Romilto C Pacheco Neto
- Division of Neurosurgery, Department of Surgery and Anatomy, University Hospital of Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Guilherme G P Gondim
- Division of Neurosurgery, Department of Surgery and Anatomy, University Hospital of Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Elvis T Valera
- Division of Pediatric Neuroncology, Department of Pediatrics, Ribeirão Preto Medical School, University of Sao Paulo, São Carlos, Brazil
| | - Maristella B F Dos Reis
- Division of Pediatric Neuroncology, Department of Pediatrics, Ribeirão Preto Medical School, University of Sao Paulo, São Carlos, Brazil
| | - Benedicto O Colli
- Division of Neurosurgery, Department of Surgery and Anatomy, University Hospital of Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Ricardo S de Oliveira
- Division of Neurosurgery, Department of Surgery and Anatomy, University Hospital of Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
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Xu JC, Lehrich BM, Yasaka TM, Fong BM, Hsu FPK, Kuan EC. Characteristics and overall survival in pediatric versus adult skull base chordoma: a population-based study. Childs Nerv Syst 2021; 37:1901-1908. [PMID: 33459820 DOI: 10.1007/s00381-021-05046-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 01/14/2021] [Indexed: 10/22/2022]
Abstract
PURPOSE Less than 5% of chordomas occur in pediatric patients. While many studies have explored the treatment and outcomes of skull base chordomas, few have focused on the differences between pediatric and adult populations. The aim of this study is to analyze the epidemiological variables and clinical outcomes between pediatric and adult skull base chordomas using a large-sample, population-based cancer database. METHODS The National Cancer Database was queried between 2004 and 2015 for skull base chordomas. We stratified patients as pediatric (<18 years) and adults (≥18 years). We compared several clinical covariates between the two groups. RESULTS Our cohort consisted of 658 patients, 61 pediatric (9.3%), and 597 adults (90.7%). Pediatric patients were more likely to have larger tumor size (41.4 ± 15.7 mm versus 34.1 ± 15.8 mm, p < 0.01) and universally treated at academic facilities. There was no significant difference in overall survival. CONCLUSIONS Pediatric skull base chordomas are rare tumors that are managed with aggressive surgical resection, followed by radiation. While there may be difference between tumor presentation, outcomes between pediatric and adult patients are similar.
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Affiliation(s)
- Jordan C Xu
- Department of Neurosurgery, University of California, Irvine, CA, USA
| | - Brandon M Lehrich
- Medical Scientist Training Program, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, PA, USA
| | - Tyler M Yasaka
- Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine, Orange, CA, USA
| | - Brendan M Fong
- Department of Neurosurgery, University of California, Irvine, CA, USA
| | - Frank P K Hsu
- Department of Neurosurgery, University of California, Irvine, CA, USA
| | - Edward C Kuan
- Department of Neurosurgery, University of California, Irvine, CA, USA. .,Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine, Orange, CA, USA.
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Marcus HJ, Rasul FT, Hussein Z, Baldeweg SE, Spoudeas HA, Hayward R, Jeelani NUO, Thompson D, Grieve JP, Dorward NL, Aquilina K. Craniopharyngioma in children: trends from a third consecutive single-center cohort study. J Neurosurg Pediatr 2020; 25:242-250. [PMID: 31860822 DOI: 10.3171/2019.10.peds19147] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Accepted: 10/21/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The management of children with craniopharyngioma has evolved over time, with a trend toward less invasive neurosurgical approaches as surgeons have sought to balance oncological control and treatment-related morbidity. To this end, the aim of this study was to evaluate the safety and effectiveness of the current management of children with craniopharyngioma compared to the previous management methods used at the authors' treatment center. METHODS A prospectively maintained database was searched over a 14-year period between January 1, 2005, and December 31, 2018, to identify all children 17 years of age or younger with a new diagnosis of craniopharyngioma. A retrospective case note review was performed for each child to extract data on the presentation, investigation, treatment, and outcome of their illness. Morbidity was assessed in the same fashion as in previous cohorts, according to the following categories: visual loss, pituitary dysfunction, hypothalamic dysfunction, neurological deficits, and cognitive impairment. RESULTS In total, 59 children were identified with craniopharyngioma during the study period. A total of 92 operations were performed, including cyst drainage (35/92; 38.0%), craniotomy and resection (30/92; 32.6%), and transsphenoidal resection (16/92; 17.4%). Approximately two-thirds of all operations were performed using image guidance (66/92; 71.7%) and one-third were performed using endoscopy (27/92; 29.3%). The majority of children had adjuvant therapy comprising proton beam therapy (18/59; 30.5%) or conventional radiotherapy (16/59; 27.1%). The median follow-up duration was 44 months (range 1-142 months), and approximately one-half of the children had no evidence of residual disease on MRI studies (28/59; 47.5%). Of the remaining 31 children, there was a reduction in the volume of residual disease in 8 patients (8/59; 13.6%), stable residual disease in 18 (18/59; 30.5%), and tumor growth in 5 patients (5/59; 8.5%). There was significantly reduced morbidity (p < 0.05) in all categories in the current cohort compared with our last cohort (1996-2004). CONCLUSIONS The authors' institutional experience of pediatric craniopharyngioma confirms a trend toward less invasive neurosurgical procedures, most of which are now performed with the benefit of image guidance or endoscopy. Moreover, the authors have identified an expanding role for more targeted radiotherapy for children with residual disease. These advances have allowed for tumor control comparable to that achieved in previous cohorts, but with significantly reduced morbidity and mortality.
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Affiliation(s)
- Hani J Marcus
- 1Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London
- 2Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London
| | | | - Ziad Hussein
- 1Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London
- 4Department of Endocrinology, University College London Hospital, London, United Kingdom
| | - Stephanie E Baldeweg
- 1Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London
- 4Department of Endocrinology, University College London Hospital, London, United Kingdom
| | | | | | | | | | - Joan P Grieve
- 1Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London
| | - Neil L Dorward
- 1Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London
- 2Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London
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Chen P, Wu WJ, Yi ZQ, Ma XL, Zhao WH, Zhang JG. 125 I interstitial brachytherapy in management of pediatric skull base tumors. Pediatr Blood Cancer 2019; 66:e27622. [PMID: 30666774 DOI: 10.1002/pbc.27622] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 01/05/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND The purpose of this study was to present our preliminary assessment of the safety and efficacy of 125 I interstitial brachytherapy (IBT) in the management of pediatric skull base tumors. METHODS Thirty pediatric patients with skull base tumors treated with 125 I IBT from April 2007 to May 2017 were included in this study. The probabilities of local control (LC) and overall survival (OS) were calculated by the Kaplan-Meier method. RESULTS The one- and two-year LC rates were 96.7% and 74.8%, respectively. The one- and two-year OS rates were 93.3% and 72.2%, respectively. No severe acute toxicity was observed. Severe late toxicities were observed in one (3.33%) of 30 patients. CONCLUSION 125 I IBT is effective and safe in the management of pediatric skull base tumors, with satisfactory cosmetic and functional outcomes.
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Affiliation(s)
- Peng Chen
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China
| | - Wen-Jie Wu
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China
| | - Zhi-Qiang Yi
- Department of Neurosurgery, Peking University First Hospital, Beijing, China
| | - Xiao-Li Ma
- Beijing Key Laboratory of Pediatric Hematology Oncology; National Key Discipline of Pediatrics, Ministry of Education; Key Laboratory of Major Diseases in Children, Ministry of Education; Hematology Oncology Center, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Wei-Hong Zhao
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Jian-Guo Zhang
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China
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Zou Y, Neale N, Sun J, Yang M, Bai HX, Tang L, Zhang Z, Landi A, Wang Y, Huang RY, Zhang PJ, Li X, Xiao B, Yang L. Prognostic Factors in Clival Chordomas: An Integrated Analysis of 347 Patients. World Neurosurg 2018; 118:e375-e387. [DOI: 10.1016/j.wneu.2018.06.194] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2017] [Revised: 06/21/2018] [Accepted: 06/22/2018] [Indexed: 12/11/2022]
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Stapleton AL, Tyler-Kabara EC, Gardner PA, Snyderman CH. Endoscopic endonasal surgery for benign fibro-osseous lesions of the pediatric skull base. Laryngoscope 2015; 125:2199-203. [PMID: 26108687 DOI: 10.1002/lary.25070] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2014] [Indexed: 11/07/2022]
Abstract
OBJECTIVES/HYPOTHESIS To describe the presentation, treatment, and outcomes of benign fibro-osseous tumors involving the skull base in a pediatric population. METHODS Retrospective chart review from January 2002 to September 2013 of pediatric patients (ages 0-18 years) who underwent endoscopic endonasal surgery (EES) for benign fibro-osseous tumors involving the skull base. RESULTS Fourteen patients were identified with an age range of 2.7 to 17.9 years (mean, 12.5 years). Six juvenile ossifying fibromas, five benign fibro-osseous lesions, two osteomas, and one fibrous dysplasia were treated. Ocular symptoms and nasal obstruction were the most common presenting symptoms in nine (64%) and six (43%) of patients, respectively; five (36%) presented with proptosis and four (29%) with diplopia. Two (14%) patients had cranial nerve VI palsy. Transsellar and transclival approaches were used in five (36%) of patients. Orbital and optic nerve decompressions were the most common components of the approaches performed in nine (64%) of the surgeries. Gross total resection (GTR) was achieved with single-stage surgery in 10 (71%) patients; two additional patients underwent staged GTR. Two intraoperative cerebrospinal fluid (CSF) leaks occurred and were repaired endoscopically. There were no postoperative CSF leaks or infectious complications. Two patients had transient diplopia, and two had transient diabetes insipidus, all of which resolved. The mean follow-up was 13.8 months. Two patients had a recurrence, and both required additional EES achieving GTR. CONCLUSIONS EES for benign fibro-osseous tumors of the skull base is a safe and effective treatment for excision of these lesions in the pediatric population. LEVEL OF EVIDENCE 4.
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Affiliation(s)
| | - Elizabeth C Tyler-Kabara
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, U.S.A
| | - Paul A Gardner
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, U.S.A
| | - Carl H Snyderman
- Department of Otolaryngology-Head and Neck Surgery.,Department of Neurological Surgery, University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, U.S.A
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Gump WC. Meningiomas of the pediatric skull base: a review. J Neurol Surg B Skull Base 2014; 76:66-73. [PMID: 25685652 DOI: 10.1055/s-0034-1390012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 06/14/2014] [Indexed: 10/24/2022] Open
Abstract
Pediatric skull base meningiomas are rare and complex clinical entities. Meningioma is a relatively uncommon brain tumor in children, and only ∼ 27% involve the skull base. Some evidence suggests that these tumors are more likely to be atypical or malignant in children than adults. The absence of female preponderance in pediatric meningiomas is reflected in the skull base subpopulation. Skull base meningiomas in children are most likely to be found in the anterior or middle fossa base, or involving the orbit and optic nerve sheath. Petroclival, suprasellar/parasellar, cerebellopontine angle, cavernous sinus, and foramen magnum tumors are very rare. Meningiomas constitute a small proportion of reported cases of pediatric skull base pathology, and they are entirely absent from many case series. Initial gross total resection is consistently associated with superior outcomes. Surgical approaches to the pediatric skull base must take additional factors into consideration including relatively smaller anatomy, immature dentition, incompletely aerated sinuses and air cells, and altered configurations of structures such as the pterional bony complex. Multidisciplinary expertise is essential to optimizing treatment outcomes.
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Affiliation(s)
- William C Gump
- Division of Pediatric Neurosurgery, Norton Neuroscience Institute and Kosair Children's Hospital, Louisville, Kentucky, United States
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Stapleton AL, Tyler-Kabara EC, Gardner PA, Snyderman CH. The costs of skull base surgery in the pediatric population. J Neurol Surg B Skull Base 2014; 76:39-42. [PMID: 25685648 DOI: 10.1055/s-0034-1390019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 06/16/2014] [Indexed: 10/24/2022] Open
Abstract
Objectives To determine the costs of endoscopic endonasal surgery (EES) for pediatric skull base lesions. Methods Retrospective chart review of pediatric patients (ages 1 month to 19 years) treated for skull base lesions with EES from 1999 to 2013. Demographic and operative data were recorded. The cost of care for the surgical day, intensive care unit (ICU), floor, and total overall cost of inpatient stay were acquired from the finance department. Results A total of 160 pediatric patients undergoing EES for skull base lesions were identified. Of these, 55 patients had complete financial data available. The average total inpatient and surgical costs of care were $34, 056 per patient. Angiofibromas were the most costly: $59,051 per patient. Fibro-osseous lesions had the lowest costs: $10,931 per patient. The average ICU stay was 1.8 days at $4,577 per ICU day. The average acute care stay was 3.4 days at $1,961 per day. Overall length of stay was 4.5 days. Three cerebrospinal fluid leaks (4%) and two cases of meningitis (3%) occurred. One tracheostomy was required (1.5%). Conclusions EES is a cost-effective model for removal of skull base lesions in the pediatric population. Costs of care vary according to pathology, staged surgeries, length of ICU stay, and need for second operations.
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Affiliation(s)
- A L Stapleton
- Department of Otolaryngology, University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, United States
| | - E C Tyler-Kabara
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, United States
| | - P A Gardner
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, United States
| | - C H Snyderman
- Department of Otolaryngology, University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, United States ; Department of Neurological Surgery, University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, United States
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