Risk factors for cerebrospinal fluid leak in pediatric patients undergoing endoscopic endonasal skull base surgery

Special Considerations in Pediatric Endoscopic Skull Base Surgery

Originally pioneered in adults, endoscopic endonasal approaches for skull base pathology are being increasingly applied as a minimally invasive alternative for young children. Intrinsic anatomic differences between these patient populations have sparked discussions on the feasibility, safety, and efficacy of these techniques in pediatric patients. This work aims to serve as a primer for clinicians engaged in the rapidly evolving field of pediatric endoscopic skull base surgery. A succinct overview of relevant embryology, sinonasal anatomy, and diagnostic workup is presented to emphasize key differences and unique technical considerations. Additional discussions regarding select skull base lesions, reconstructive paradigms, potential surgical complications, and postoperative care are also highlighted in the setting of multidisciplinary teams.

CSF leak after pediatric endoscopic endonasal expanded approaches: a series review

PURPOSE

Endoscopic endonasal approaches in the pediatric population pose specific challenges. Management of postoperative cerebrospinal fluid [CSF] leak is probably the major concern. The purpose of the present investigation is to describe and analyze the incidence of postoperative CSF leaks in our pediatric series of endoscopic endonasal approaches.

METHODS

This is a retrospective analysis, case review of our institutional series. Descriptive statistical parameters and bivariate correlations are analyzed.

RESULTS

Twenty-one patients have been operated through endoscopic approaches in our series. Four patients showed a postoperative CSF leak needing a revision surgery; these cases are described in further detail. Approaches expanded beyond the sellar area and non-sellar pneumatization of the sphenoid sinus were significantly associated with a higher risk of postoperative CSF leak.

CONCLUSIONS

CSF leak incidence after endoscopic endonasal approaches is higher in pediatric patients than in adult series. Anatomic and pathologic factors add complexity to these approaches in children. Multilayer closure is advisable to prevent and treat this complication.

Management of a pediatric patient with spontaneous cerebrospinal fluid leak in the lateral recess of sphenoid sinus and meningoencephalocele: A case report and literature review

INTRODUCTION AND IMPORTANCE

Spontaneous cerebrospinal fluid (CSF) leak in the lateral recess of the sphenoid (LRS) sinus in a pediatric population is rare and is surgically challenging to repair.

CASE PRESENTATION

We report a case of a 13-year-old girl with hydrocephalus and a ventriculoperitoneal shunt who presented with a two-month history of clear rhinorrhea from the right nostril. Computed tomography (CT) of the head was performed and showed CSF leak through a defect in the lateral recess of the sphenoid sinus. Defect closure was achieved using an endoscopic endonasal approach.

CLINICAL DISCUSSION

CSF leak with meningoencephalocele from the sphenoid sinus is amongst the most difficult cases for repair. Yet the successful rate of repair is as high as 90 % if done endoscopically. Moreover, the location of the defect determines the surgical approach.

CONCLUSION

Spontaneous CSF rhinorrhea from the lateral recess of the sphenoid (LRS) sinus, although rare, requires prompt diagnosis and treatment, as it may lead to significant mortality and morbidity.

Reducing CSF complications by a recycled Hadad's flap combined with autologous mucosa in secondary endoscope transsphenoidal surgery

Background

Transsphenoidal secondary operations are a minority but not a rare occurrence. How to viably prevent cerebral fluid (CSF)-related complications and confine surgery-caused injury in secondary surgery as minimally as possible is a huge challenge. This article shares our solution of recycling a prior Hadad-Bassagasteguy flap (HBF) along with a using small piece of free autologous mucosa to reconstruct the skull base.

Methods

Of 69 patients, fitted criteria were assigned into 2 different groups: a recycled HBF incorporated with an autologous free mucosa and a recycled HBF incorporated with an artificial dura to rebuild the skull base in secondary transsphenoidal surgery. The postoperative morbidities of pseudomeningocele, CSF leakage and meningitis were recorded and analyzed.

Results

A recycled HBF incorporated with an autologous mucosa is capable of reducing CSF complications compared to that of the matched group, particularly decreasing the morbidity of meningitis in secondary transsphenoidal surgery. Diabetes mellitus, craniopharyngioma, chordoma and the utilization of artificial dura were independent risk factors for CSF complications in secondary transsphenoidal surgery through univariate and multivariate logistic regression. In addition, diabetes mellitus and artificial dura are more likely to induce CSF leakage and meningitis. Patients suffering from craniopharyngioma are more susceptible to meningitis. Chordoma indiscriminately increased the risk of each CSF complication.

Conclusion

A recycled HBF incorporated with an autologous mucosa is reliable for reconstructing the skull base in secondary transsphenoidal surgery, especially for patients simultaneously suffering from diabetes mellitus and central skull base tumors.

Characteristics and Outcomes in Pediatric Versus Adult Craniopharyngiomas: A Systematic Review and Meta-Analysis

BACKGROUND

Craniopharyngiomas account for 1.2% to 4.6% of all intracranial tumors. Although age at presentation is distributed bimodally, with a pediatric peak occurring between 5 and 15 years and an adult peak between 50 and 70 years, presentation, treatment, and outcome differences between these two craniopharyngioma populations have not been thoroughly characterized.

OBJECTIVE

To compare treatments and outcomes between adult and pediatric craniopharyngiomas.

METHODS

This is a systematic review and meta-analysis. Web of Science, MEDLINE, and Scopus databases were searched for primary studies reporting postoperative complications, functional outcomes, recurrence, and overall survival in patients with craniopharyngioma undergoing surgery.

RESULTS

The search yielded 1,202 unique articles, of which 106 (n=4,202 patients) met criteria for qualitative synthesis and 23 (n=735 patients) met criteria for meta-analysis. Compared with adult, pediatric craniopharyngiomas were less likely to present with visual defects (odds ratio [OR] 0.54, 95% CI 0.36-0.80) or cognitive impairment (OR 0.29, 95% CI 0.12-0.71) and more likely with headaches (OR 2.08, 95% CI 1.16-3.73). Children presented with significantly larger tumors compared with adults (standardized mean difference 0.68, 95% CI 0.38-0.97). Comparing functional outcomes, pediatric patients sustained higher rates of permanent diabetes insipidus (OR 1.70, 95% CI 1.13-2.56), obesity (OR 3.15, 95% CI 1.19-8.31), and cranial nerve and/or neurological defects (OR 4.87, 95% CI 1.78-13.31) than adults. No significant differences were found in rates of postoperative cerebrospinal fluid leak, overall or progression-free survival, or recurrence.

CONCLUSION

Adult and pediatric craniopharyngiomas seem to have fundamental differences in clinical presentation and functional outcomes. These patients frequently require multimodality treatment and are best managed with a multidisciplinary team and an individualized approach.

Risk Factors for Postoperative Cerebrospinal Fluid Leak after Graded Multilayer Cranial Base Repair with Suturing via the Endoscopic Endonasal Approach

This study analyzed risk factors for postoperative cerebrospinal fluid (CSF) leak after graded multilayer cranial base repair method with dural suturing. We performed surgery via the endoscopic endonasal approach (EEA) from 2012.6 to 2018.4, and those consecutive clinical data were prospectively accumulated and retrospectively analyzed. We tailored the repair method according to the intraoperative CSF leak grade. Among 388 surgeries via the EEA, there were 10 (2.6%) cases of postoperative CSF leak after graded repair with suturing. Postoperative CSF leak occurred in two of the 150 cases without intraoperative CSF leak (grade 0), one of the 104 cases with small (grade 1) intraoperative CSF leak, two of the 60 cases with moderate (grade 2) leak, and five of the 74 cases with large (grade 3) leak. Univariate analysis indicated that chordoma (P = 0.023), estimated tumor volume ≥ 7400 mm³ (P = 0.003), and maximum tumor diameter ≥ 32.5 mm (P = 0.001) were significant risk factors for postoperative CSF leak. Additionally, among cases with intraoperative grade 3 CSF leak, chordoma (P = 0.021), estimated tumor volume ≥ 23000 mm³ (P = 0.003), and maximum tumor diameter ≥ 45.5 mm (P = 0.001) were significant risk factors for postoperative CSF leak. Maximum tumor diameter, estimated tumor volume, and chordoma tumor pathology are related to a higher risk of postoperative CSF leak.

Neurosurgical Treatment and Outcome of Pediatric Skull Base Lesions: A Case Series and Review of the Literature

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.

Endoscopic Endonasal Skull Base Surgery Complication Avoidance: A Contemporary Review

The endoscopic endonasal approach (EEA) provides a direct trajectory to ventral skull base lesions, avoidance of brain retraction, and clear visualization of cranial nerves as they exit skull base foramina. Despite these benefits, the EEA is not without complications. Here, we review published literature highlighting complications associated with the EEA including cerebrospinal fluid (CSF) leak, cranial nerve (CN) dysfunction, pituitary gland dysfunction, internal carotid artery (ICA) injury, infection, and others; we place special emphasis on discussing the prevention of these complications. As widespread adoption of the EEA continues, it becomes critical to educate surgeons regarding potential complications and their prevention while identifying gaps in the current literature to guide future research and advances in clinical care.

Bath‐plug technique for the endoscopic management of cerebrospinal fluid leaks in children

Importance

The safety and efficacy of the bath-plug technique for the closure of cerebrospinal fluid (CSF) leaks in children remain unknown.

Objective

We undertook this study to ascertain whether the bath-plug technique was safe and effective for the repair of CSF leaks.

Methods

We retrospectively reviewed patients who underwent endoscopic repair of CSF leaks with the fat graft as a plug-in at Beijing Children's Hospital from March 2016 to May 2020. Demographic data, medical history, defect sites and sizes, interventions, and clinical outcomes were analyzed. One representative clinical case was additionally selected to highlight the procedure and the healing process.

Results

A total of 18 pediatric patients were included in this study. The group was composed of 11 boys and seven girls, aged from 5 to 123 months. The etiologies included congenital CSF leaks (n = 9) and head trauma (n = 9). Among all patients, 12 fistulas (66.7%) were located at the cribriform plate area, two (11.1%) at the roof of the ethmoid sinuses, two (11.1%) in the sphenoid sinus, and two (11.1%) at the frontal sinus. The maximum diameters of fistulas ranged from 5 to 20 mm, with a median value of 8 mm. Encephaloceles were identified in 14 (77.8%) patients. No hydrocephalus was recognized. All CSF leaks were successfully repaired with a bath-plug technique. Follow-up ranged from 50 to 70 months. No surgical complications were encountered in any patient.

Interpretation

Bath-plug technique is safe and reliable for the endoscopic management of CSF leaks in children. Meticulous peri-operative preparations are important for pediatric patients.

Risk Factors in a Pediatric Population for Postoperative Intracranial Infection Following Endoscopic Endonasal Skull Base Surgery and the Role of Antibiotic Prophylaxis

BACKGROUND

Endoscopic endonasal skull base surgery (EESBS) is performed through a non-sterile corridor. Intracranial infection rates in a pediatric population have not been extensively studied and the exact effect of antibiotic prophylaxis on rates of infection after EESBS in pediatric patients remains unclear.

OBJECTIVE

The purpose of our study is to investigate risk factors for postoperative intracranial infection during EESBS in a pediatric population and help elucidate the role of antibiotic prophylaxis.

METHODS

We conducted a retrospective chart review of 99 consecutive patients under the age of 18 who underwent EESBS at our institution from 2013 to 2021. Centers for Disease Control and Prevention/National Healthcare Safety Network criteria for diagnosis of meningitis were used to identify postoperative intracranial infections.

RESULTS

The average age was 12.3 years (range 1.6-18) with 66 male patients and 33 female patients. 49 patients had an intraoperative cerebrospinal fluid (CSF) leak, of which 4 had a postoperative CSF leak. We identified 3 postoperative intracranial infections (3%), which were all meningitis cases. The infection rate was 6% (3/49) among those with intraoperative CSF leaks. All patients with meningitis had a postoperative CSF leak. All infections were transclival approaches (2 chordoma and 1 neurenteric cyst).

CONCLUSION

This investigation represents one of the largest pediatric endoscopic skull base surgery cohorts. EESBS is safe to perform in pediatric populations, but transclival approaches and postoperative CSF leaks are risk factors for postoperative meningitis.

Application of dural suturing in the endoscopic endonasal approach to the sellar region

Objectives

The endoscopic endonasal approach (EEA) is widely used in the treatment of cranial base tumors. Skull base reconstruction is a crucial part of EEA, which has a great impact on patients’ prognosis. In this study, we report our experience with sellar dural suturing in cranial base reconstruction and retrospectively analyze its effect.

Methods

The clinical data of 134 patients who suffered intraoperative CSF leakage and underwent EEA surgery in the Department of Neurosurgery of the First Affiliated Hospital of Nanjing Medical University from October 2018 to November 2020 were retrospectively collected and analyzed. According to whether sellar dural suturing was performed during the operation, they were divided into a suture group (55 cases) and a control group (79 cases).

Results

The results showed that dural suturing of the sellar floor effectively reduced the postoperative hospitalization duration (p = 0.026) and the use rates of lumbar drainage (p = 0.047), autologous fat transplantation (p = 0.038), and pedicled nasoseptal flaps (p = 0.026).

Conclusion

Sellar dural suturing under endoscopy is a promising and effective method for cranial base reconstruction in EEA surgery and is worthy of clinical application.

Risk Factors and Reconstruction Techniques for Persistent Cerebrospinal Fluid Leak in Patients Undergoing Endoscopic Endonasal Approach to the Posterior Fossa

Background High-flow skull base dural defects are associated with an increased risk of postoperative cerebrospinal fluid (CSF) leaks.

Objective This study aimed to identify the risk factors for persistent postoperative CSF leak after endoscopic endonasal surgery (EES) and determine the ideal reconstruction strategy after initial failed repair.

Methods Patients with CSF leak after intradural EES between October 2000 and February 2017 were identified. Cases with persistent CSF leak were compared with patients with similar pathologic diagnosis without a persistent leak to identify additional risk factors.

Results Two hundred and twenty-three out of 3,232 patients developed postoperative CSF leak. Persistent leaks requiring more than one postoperative repair occurred in 7/223 patients (3.1%). All seven had undergone intradural approach to the posterior fossa for resection of recurrent/residual clival chordomas. This group was matched with 25 patients with recurrent/residual clival chordoma who underwent EES without postoperative CSF leak (control group). Age, gender, history of diabetes, smoking, or radiotherapy were not statistically different between the groups. Obesity (body mass index > 30) was significantly more common in the group with persistent leak (86%) compared with controls (36%) (p = 0.02). All patients with a persistent CSF leak developed meningitis (p = 0.001). Five patients with persistent leak required a pericranial flap to achieve definitive repair.

Conclusion Multiple recurrent CSF leak after EES primarily occurs following resection of recurrent/residual posterior fossa chordoma. Obesity is a major risk factor and meningitis is universal with persistent leak. Flap necrosis may play a role in the development of persistent CSF leaks, and the use of secondary vascularized flaps, specifically extracranial–pericranial flaps, should be considered as an early rescue option in obese patients.

Outcomes of endoscopic endonasal resection of pediatric craniopharyngiomas

BACKGROUND

Craniopharyngiomas have traditionally been treated via open transcranial approaches. More recent, endoscopic endonasal approaches have been increasingly used; however, there has been limited evaluation of long-term outcomes for this approach.

METHODS

A retrospective review was performed to analyze patients with pediatric craniopharyngioma undergoing endonasal endoscopic resection from 2012 to 2020. Demographic information, clinicopathologic factors, and outcomes including follow-up and recurrences were analyzed.

RESULTS

All 42 patients, with a mean age of 8.0 years, were included. The median follow-up time was 49 months. Mean tumor diameter was 3.6 cm. All of the tumors had sellar and suprasellar components. The most common presenting symptoms were headaches (64.3%), visual changes (59.5%), and nausea/vomiting (38.1%). Most patients (73.3%) had resolution of their presenting symptoms by their first postoperative visit. Vision improved or remained normal in 69.0% of patients. Postoperatively, incidence of panhypopituitarism or diabetes insipidus developed in 89.7% and 77.8% of patients, respectively. The postoperative cerebrospinal fluid leak rate was 7.1%. The recurrence rate was 9.5%.

CONCLUSION

Endoscopic endonasal resection for pediatric craniopharyngiomas can achieve high rates of resection with low rates of disease recurrence when compared with the outcomes of open transcranial resection reported in the literature. However, hypothalamic-pituitary dysfunction remains a significant postoperative morbidity in both approaches.

Extended Neuroendoscopic Endonasal Approach for Resection of Craniopharyngioma in Children

Objective

To explore the surgical approach and technique of neuroendoscopic endonasal resection of pediatric craniopharyngiomas and to further evaluate its safety and effect in children.

Methods

The clinical data of 8 children with craniopharyngiomas who were surgically treated by neuroendoscopy through an extended endonasal approach in our center from 2018 to 2021 were retrospectively analyzed. The related surgical approach and technique were evaluated to improve the surgical results and further reduce the surgical complications when removing craniopharyngioma in children.

Results

All 8 patients achieved a gross-total resection of the tumor under neuroendoscopy. Postoperatively, 2 cases of transient hyperthermia and 4 cases of transient hyper- and/or hyponatremia occurred within the first 2 weeks, all of which were quickly controlled. Seven patients had symptoms of diabetes insipidus to varying degrees after the operation, and 4 of them improved within 1–3 months after surgery, but 3 cases still needed oral pituitrin. There were no cases of coma or death, leakage of cerebrospinal fluid, or severe electrolyte imbalance after surgery. During the postoperative follow-up of 3 months to 2 years, no tumor recurrence was found. Among the 7 patients who suffered postoperative neuroendocrine deficiencies, 3 patients were found to be temporary during the follow-up, but 4 patients still required hormone replacement therapy. Particularly, postoperative visual deterioration and olfactory defect that occurred in patients were all improved during follow-up periods. In addition, 4 cases of obesity were noted at the last follow-up.

Conclusions

Extended neuroendoscopic endonasal resection of craniopharyngiomas may be used as a safe and effective approach for children. Due to the poor pneumatization of the sphenoid sinus and worse compliance of treatment in children, surgical techniques of exposing the sellar region, removing the tumor, and reconstructing the skull base, as well as postoperative management of patients was proposed. However, due to the limited surgical cases in the study, the surgical safety and effects of the extended neuroendoscopic endonasal approach for children with craniopharyngiomas need to be further studied in the future.

Clinical management of pediatric chordomas: a comprehensive review

Chordomas are malignant tumors derived from remnants of the notochord. These are extremely rare in pediatric patients, accounting for approximately 5% of all chordomas, with most lesions occupying the cranium. Chordomas also can occupy all levels of the spine, demonstrating a broad spectrum of neurologic presentation. Optimal treatment aims for gross total resection with accompanying radiation therapy to prevent recurrence. Their aggressive and infiltrative nature makes clinical management challenging, involving multiple disciplines and close monitoring to ensure optimal outcomes. This comprehensive review aims to cover the genetics, demographics, pathogenesis, neurologic sequelae, radiological considerations, chemotherapeutic management, surgical management, and post-operative considerations of pediatric chordoma patients.

Heterogeneity in Outcome Reporting in Endoscopic Endonasal Skull Base Reconstruction: A Systematic Review

Objective  Presently, there are no standards for reporting outcomes of endoscopic endonasal skull base reconstruction (ESBR). This is problematic as a lack of consistent reporting makes synthesizing findings in systematic reviews and meta-analysis challenging. Thus, the aim of this study was to systematically review and describe the patterns of reporting outcomes in ESBR as a foundation for developing reporting guidelines. Study Design  Present study is a systematic review. Methods  Embase, PubMed, CINAHL, Cochrane Library, and Web of Science were searched for all publications with ≥25 patients and a focus on ESBR. The reporting patterns of each study's variables and outcomes were assessed. Results  A total of 112 studies were included in the review. The most commonly reported demographic variables were the number of included patients ( n  = 112, 100%) and types of pathologies treated ( n  = 104, 92.9%). Meanwhile, the most routinely described preoperative variable was history of prior treatment ( n  = 48, 42.9%). Type of reconstruction was a commonly reported intraoperative variable ( n  = 110, 98.2%), though the rate of intraoperative cerebrospinal fluid (CSF) leak was noted in only 76 studies (67.9%). With regard to postoperative outcomes, postoperative CSF leak rate was routinely provided ( n  = 101, 90.2%), but reporting of other surgical complications was more inconsistent. Ultimately, of the 43 variables and outcomes reviewed, a median of 12 (range: 4-22) was reported in each study. Conclusion  There is significant heterogeneity in the outcomes reported in studies relating to ESBR. This highlights the need for the development of standard reporting guidelines to minimize bias and improve interstudy comparability.

Pediatric Skull Base Tumors: A Management Challenge

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.

Characteristics and overall survival in pediatric versus adult skull base chordoma: a population-based study

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.

Applications of Endoscopic Endonasal Surgery in Early Childhood: A Case Series

INTRODUCTION

Endoscopic endonasal surgery (EES) has been slower to gain popularity in early childhood due to anatomical challenges. We sought to describe the safety and efficacy of EES in early childhood.

METHODS

All patients younger than 7 years who underwent EES at a large Cranial Base Center from 2002 to 2019 were reviewed as a retrospective cohort study.

RESULTS

Thirty-six patients underwent EES before the age of 7 years. Four patients had two-stage EES. Two patients required combined transcranial and endonasal approaches. The mean age at the time of initial surgery was 4 years (range: 1-6). Twenty patients were male, and 16 were female. Of 21 tumors intended for resection, 11 patients had gross total resections, and 10 had near total (>95% tumor removed) resections. Nine patients (43%) had recurrences, of which 6 were craniopharyngiomas (p = 0.01). There was no difference in recurrence rates based on the degree of resection (p = 0.67). Three cerebrospinal fluid (CSF) leaks occurred following primary EES (8%). Following an increase in nasoseptal flap usage (31-52%) and CSF diversion (15-39%) in 2008, there was only one CSF leak out of 23 patients (4 vs. 15%; p = 0.54). Postoperatively, 1 patient developed a permanent new cranial neuropathy, and 1 patient developed a permanent visual field cut. Six patients developed permanent postoperative panhypopituitarism, of which all were craniopharyngiomas (p < 0.001). The mean follow-up was 64 months.

CONCLUSIONS

Early childhood EES is both safe and technically feasible for a variety of pathologies.

Management of anterior fossa cephaloceles

Skull base cephaloceles (SBCs) are defined as herniation of intracranial content through the skull base and are classified based on composition, etiology, and topographic location. Anterior SBCs frequently protrude in the sinonasal cavity, and consequently are at potential risk of infection. Therefore, the current recommendation is to treat SBCs with the primary intent of preventing meningitis, and surgery represents the mainstay of treatment. Anterior SBCs may display a wide spectrum of severity and complexity, and in each case the risks and benefits of surgical approaches are to be carefully weighted based on thorough assessment of symptoms, age, general conditions, location and size of the lesion, as well as expertise of the surgeon. In the last 30 years, the evolution and diffusion of transnasal endoscopic surgery have substantially changed the surgical management of the majority of SBC. In the past, they were treated exclusively with open transcranial approaches that may be burdened by relevant morbidity and risk for severe complications. The transnasal endoscopic corridor now provides easy access to the lesion and different reconstructive strategies using endonasal pedicled flaps, without any external incision, cranioplasty or brain manipulation. However, there are still scenarios in which an exclusive transnasal endoscopic route is contraindicated. The aim of the present review was to provide an overview on the comprehensive management of anterior SBC, with a particular focus on lesions suitable for endoscopic surgery. Furthermore, special aspects of SBC management in children and adults will be highlighted.

Reconstruction of pediatric skull base defects: A retrospective analysis emphasizing the very young

INTRODUCTION

Pathology of the pediatric skull base is rare and ranges from congenital defects to malignancy and traumatic defects. Pediatric patients, particularly those ≤6 years of age, present a unique set of anatomic challenges for the skull base surgeon. The goal of this study was to retrospectively review our experience with reconstruction of pediatric skull base defects with particular emphasis on those ≤6 years of age.

METHODS

A retrospective chart review was conducted of patients ≤20 years of age who underwent endoscopic endonasal and combined endoscopic and open approaches to address cranial base pathology from 2007 to 2018. Patients were divided into two groups; those ≤6 years of age (group A) and those >6 years of age and ≤20 years of age (group B) and reconstructive techniques and outcomes were analyzed.

RESULTS

Intraoperative communication with the subarachnoid space (CSF leak) was created in 50% (3/6) of patients ≤ 6 years of age compared to 32.7% (16/49) in patients > 6 years and ≤20 years of age (P < 0.40) in management of their skull base disease. A vascularized flap was utilized for reconstruction in 66.7% (4/6) of patients ≤ 6 years of age and included a nasoseptal flap in 33.3% (2/6). A vascularized flap was utilized for reconstruction in 38.8% (19/49) of patients > 6 years and ≤20 years of age and most commonly included a nasoseptal flap (22.4%, 11/49). A lumbar drain was utilized in 50% (3/6) of patients ≤ 6 years of age compared to 18.4% (9/49) in patients > 6 and ≤20 years of age (P < 0.08). Post-operative CSF leaks were encountered in 16.7% (1/6) of patients ≤ 6 years of age compared to 10.2% (5/49) in patients > 6 and ≤20 years of age (P < 0.63). Behavioral issues were noted to potentially contribute to failed skull base reconstruction in patients <6 years of age.

CONCLUSIONS

Pediatric patients, particularly those ≤6 years of age, present a unique set of anatomic and behavioral challenges for the skull base surgeon as highlighted in this study.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Endonasal endoscopic surgery for pediatric anterior cranial fossa encephaloceles: A systematic review

BACKGROUND

Endoscopic endonasal skull base surgery (ESBS) is a well-established management strategy for anterior cranial fossa (ACF) encephaloceles in adults. However, its application to the pediatric population has not been evaluated in large-scale studies. This study systematically reviews the safety of ESBS for pediatric ACF encephaloceles.

METHODS

Articles reporting on pediatric patients undergoing purely ESBS for encephaloceles were reviewed from three databases (PubMed, Scopus, and Cochrane Library). Main outcomes were post-operative cerebrospinal fluid (CSF) leak and other surgical complications.

RESULTS

Twenty-three articles provided data on 110 eligible patients with a mean age of 4.3 years (range birth - 18 years). Intraoperative CSF leaks occurred in 18.5% of children while post-operative CSF leaks developed in 6.0% of cases. Rates of meningitis and hydrocephalus were each 3.7%. Other complications included alar collapse, nasal stenosis, transient diabetes insipidus, pneumonia, and neurologic injury, collectively occurring in 7.0% of cases. The rate of death was 4.8%. The average duration of follow-up was 25.3 months. Encephaloceles recurred in 5.2% of patients.

CONCLUSIONS

ESBS for pediatric ACF encephaloceles provides a relatively favorable risk-benefit profile, with a low rate of post-operative CSF leak, other surgical complications, and disease recurrence.

Skull base chordomas review of current treatment paradigms

Background

Chordomas are locally invasive neoplasms, arising from notochordal remnants and can appear anywhere along the axial skeleton. Local recurrences are common, and distant metastases may occur years after the initial presentation.

Methods

Literature review of current treatment strategies for chordomas of the skull base.

Results

Surgery is the mainstay of treatment and complete resection has paramount importance for prognosis.

When complete resection is not achieved recurrent disease is common. The anatomical complexity of the skull base makes resection complex. Endonasal endoscopic approaches to the clivus has become increasingly favored in recent years although addressing reconstruction of the skull base to prevent CSF leak may be challenging.

Evidence suggests that radiotherapy should not be considered as a primary single modality when trying to achieve cure of the disease. Nonetheless, immediate post-operative radiotherapy improves survival. Many strategies have been suggested to preserve sensitive vital structures in the skull base during treatment but as for survival there is no evidence of advantage when comparing adjuvant therapy with photon radiotherapy, gamma knife surgery, proton beam therapy, and carbon ion radiation therapy.

There is no evidence to support cytotoxic chemotherapy in the treatment of chordomas but targeted therapies have started to show promise. Several optional molecular targets exist. Brachyury is overexpressed in 95% of chordomas but not in other mesenchymal neoplasms. However, its precise role in chordoma pathogenesis is currently unclear, and its cellular location in the nucleus makes it difficult to target. The inhibition of brachyury in chordoma cell lines induces growth arrest and apoptosis. This does not have clinical application to date. There are retrospective results with different molecular targeted therapies for advanced chordomas with some effectiveness.

Conclusion

Despite improvements made in the past 10 years in our knowledge of chordoma biology, available therapies still offer a limited benefit. There is an unmet need for new therapeutic options for patients with advanced disease. Therefore, patients with advanced disease should be encouraged to participate in clinical trials when and where available.

Pediatric sinonasal and skull base lesions

Pediatric skull base lesions are complex and challenging disorders. Safe and comprehensive management of this diverse group of disorders requires the expertise of an experienced multidisciplinary skull base team. Adult endoscopic skull base surgery has evolved due to technologic and surgical advancements, multidisciplinary team approaches, and continued innovation. Similar principles continue to advance the care delivered to the pediatric population. The approach and management of these lesions varies considerably based on tumor anatomy, pathology, and surgical goals. An understanding of the nuances of skull base reconstruction unique to the pediatric population is critical for successful outcomes.

The expanded endonasal approach in pediatric skull base surgery: A review

OBJECTIVE

Surgery of the pediatric skull base has multiple unique challenges and has seen recent rapid advances. The objective of this review is to assess key issues in pediatric skull base surgery (SBS), including anatomic limitations, surgical approaches, reconstruction techniques, postoperative care, complications, and outcomes.

DATA SOURCES

PubMed literature review.

REVIEW METHODS

A review of the literature was conducted to assess the challenges, recent advances, and reported outcomes in pediatric SBS.

RESULTS

The pediatric skull base presents multiple anatomic challenges, including variable patterns of pneumatization, narrow piriform aperture width, and narrow intercarotid distance at the level of the cavernous sinus but not the superior clivus. These issues may be particularly challenging in patients less than 2 years of age. Endoscopic endonasal approaches in the sagittal and coronal plane have been applied to the pediatric skull base while open approaches may still be necessary in the setting of extensive intracranial or orbital disease, as well as disease lateral to critical neurovascular structures. While the nasoseptal flap was initially called into question for pediatric cases, it has been shown through multiple reports to be a feasible and robust reconstructive option. Complications and outcomes often depend upon the pathology. In children, response to noxious stimuli, ability to avoid Valsalva, and adherence to nasal precautions is variable. The use of lumbar drains is more common in pediatric than adult patients.

CONCLUSION

While the pediatric skull base presents unique challenges, outcomes data support that endoscopic endonasal approaches are a pertinent surgical technique in appropriately selected patients.

LEVEL OF EVIDENCE

3a.

Endonasal Endoscopic Surgery for Pediatric Sellar and Suprasellar Lesions: A Systematic Review and Meta-analysis

OBJECTIVES

The advent of endonasal endoscopic skull base surgery (ESBS) has redefined the management of pediatric sellar and suprasellar lesions. To date, the outcomes of these procedures have not been systematically reviewed. This study performed a systematic review with meta-analysis of surgical outcomes for pediatric patients undergoing ESBS for sellar and suprasellar lesions.

DATA SOURCES

PubMed (National Library of Medicine, National Institutes of Health), Scopus (Elsevier), and Cochrane Library (Wiley).

REVIEW METHODS

Articles reporting on pediatric patients undergoing ESBS for craniopharyngiomas, pituitary adenomas, and Rathke's cleft cysts were reviewed. The primary outcome was postoperative cerebrospinal fluid (CSF) leak. Secondary outcomes included endocrine, visual, and other complications.

RESULTS

Twenty-five articles reporting on 554 patients were included. Overall postoperative CSF leak rate was 8.6%, with tumor-specific rates of 10.6% in craniopharyngiomas, 6.5% in pituitary adenomas, and 7.2% in Rathke's cleft cysts (P > .05). Older studies demonstrate higher postoperative CSF leak rates as compared with more recent studies (12.5% vs 6.1%, P = .0082). Younger children (8.9-12.6 years old) experienced a higher rate of postoperative CSF leaks as compared with older children (13.0-16.6 years old; 12.9% vs 4.9%, P = .0016). Additional postoperative complications included diabetes insipidus (26.7%), hypopituitarism (46.6%), visual deficits (2.6%), meningitis (3.4%), and weight gain (3.4%).

CONCLUSION

ESBS for pediatric sellar and suprasellar lesions is overall an effective management approach with an increasingly favorable risk-benefit profile. Younger children may be more susceptible to postoperative CSF leak as compared with older pediatric patients. Tumor type does not appear to be an independent risk factor for postoperative CSF leak in this population.

Endoscopic endonasal surgery outcomes for pediatric craniopharyngioma: a systematic review

OBJECTIVE

The goal of this study was to systematically review the outcomes of endoscopic endonasal surgery (EES) for pediatric craniopharyngiomas so as to assess its safety and efficacy.

METHODS

A systematic literature review was performed using the PubMed and MEDLINE databases for studies published between 1986 and 2019. All studies assessing outcomes following EES for pediatric craniopharyngiomas were included.

RESULTS

Of the total 48 articles identified in the original literature search, 13 studies were ultimately selected. This includes comparative studies with other surgical approaches, retrospective cohort studies, and case series.

CONCLUSIONS

EES for pediatric craniopharyngiomas is a safe and efficacious alternative to other surgical approaches. Achieving gross-total resection with minimal complications is feasible with EES and is comparable, if not superior in some cases, to traditional means of resection. Ideally, a randomized controlled trial might be implemented in the future to further elucidate the effectiveness of EES for resection of craniopharyngiomas.

Endonasal endoscopic skullbase surgery in children

OBJECTIVE

The role of endonasal endoscopic approach for pathologies in the paediatric population is evolving and has still not been accepted as standard of care in neurosurgery. It represents a challenge in terms of narrow access, instrument manipulation and adequate reconstruction of defects. We have described our experience in 49 cases from a single neurosurgical unit in paediatric skull base surgeries through this approach over the last 12 years.

MATERIAL AND METHODS

A case series of 59 paediatric skull base surgeries in 49 children through endoscopic endonasal route over the last 12 years is presented. The age ranges from 4 months to 18 years. Out of 49 cases, 22 cases were of craniopharyngiomas, 8 cases of pituitary adenomas, 5 cases with CSF rhinorrhea, 5 cases with meningoencephalocele, 3 cases of Rathke's cleft cysts, 2 cases of odontoidectomy and 4 miscellaneous cases viz. mucocele, hypothalamic glioma, esthesioneuroblastoma and epidermoid. CSF leaks were repaired with free graft in the initial years and by vascularized flap more recently.

RESULTS

The goal of surgery was achieved in all but two cases in whom the tumour excision was unsatisfactory due to failure of the cyst wall to collapse after decompression. Extent of tumour excision was not compromised by the choice of this approach. Revision surgery for CSF leak was required in three patients. Local vascularized nasoseptal flap has been possible even in very young patients and has now become the standard for reconstruction.

CONCLUSION

In spite of the challenges posed by small nostrils and ill-developed sinuses in the paediatric age group, surgery from endoscopic endonasal corridor is possible to be carried out successfully in selected cases.

Endoscopic Transnasal Skull Base Surgery in Pediatric Patients

Introduction  In pediatric patients, endoscopic transnasal surgery (ETNS) poses challenges because of the small size of the developing skull and narrow endonasal corridors. Objective  This study aimed to evaluate the efficacy of ETNS in children by assessing our experience of endoscopic skull base surgery. Materials and Methods  All pediatric patients ( n  = 54) who were eligible for surgery using only the endonasal endoscopic approach at our tertiary center between 2012 and 2018 were included in this study. The surgeries were performed simultaneously by an endoscopic skull base team of neurosurgeons and otolaryngologists. Hormonal analyses were conducted before and after surgery in all patients with sellar/parasellar lesions. Patients older than 8 years underwent smell and visual testing. Results  In the 54 patients aged 1 to 17 years who underwent surgery, craniopharyngioma was the most common pathology (29.6%), followed by pituitary adenoma (22.2%). Gross total resection was achieved in 33 (76.7%) of 41 patients who underwent surgery because of the presence of tumors. All visual deficits improved, although one patient sustained olfactory deterioration. Sixteen (29.6%) patients presented with complications such as transient diabetes insipidus and temporary visual loss. Conclusions  Despite anatomy-related challenges in children, adequate results can be achieved with high rates of success, and the functional and anatomical integrity of the developing skull and nose of children can be preserved. In pediatric patients, ETNS is a safe and effective option for addressing various lesions along the skull base.

Transnasal endoscopic approach for pediatric skull base lesions: a case series

OBJECTIVE

Transnasal endoscopic transsphenoidal approaches constitute an essential technique for the resection of skull base tumors in adults. However, in the pediatric population, sellar and suprasellar lesions have historically been treated by craniotomy. Transnasal endoscopic approaches are less invasive and thus may be preferable to craniotomy, especially in children. In this case series, the authors present their institutional experience with transnasal endoscopic transsphenoidal approaches for pediatric skull base tumors.

METHODS

The authors retrospectively reviewed pediatric patients (age ≤ 18 years) who had undergone transnasal endoscopic transsphenoidal approaches for either biopsy or resection of sellar or suprasellar lesions between 2007 and 2016. All operations were performed jointly by a team of pediatric neurosurgeons and skull base otolaryngologists, except for 8 cases performed by one neurosurgeon.

RESULTS

The series included 42 patients between 4 and 18 years old (average 12.5 years) who underwent 51 operations. Headache (45%), visual symptoms (69%), and symptoms related to hormonal abnormalities (71%) were the predominant presenting symptoms. Improvement in preoperative symptoms was seen in 92% of cases. Most patients had craniopharyngiomas (n = 16), followed by pituitary adenomas (n = 12), Rathke cleft cysts (n = 4), germinomas (n = 4), chordomas (n = 2), and other lesion subtypes (n = 4). Lesions ranged from 0.3 to 6.2 cm (median 2.5 cm) in their greatest dimension. Gross-total resection was primarily performed (63% of cases), with 5 subsequent recurrences. Nasoseptal flaps were used in 47% of cases, fat grafts in 37%, and lumbar drains in 47%. CSF space was entered intraoperatively in 15 cases, and postoperative CSF was observed only in lesions with suprasellar extension. There were 8 cases of new hormonal deficits and 3 cases of new cranial nerve deficits. Length of hospital stay ranged from 1 to 61 days (median 5 days). Patients were clinically followed up for a median of 46 months (range 1-120 months), accompanied by a median radiological follow-up period of 45 months (range 3.8-120 months). Most patients (76%) were offered adjuvant therapy.

CONCLUSIONS

In this single-institution report of the transnasal endoscopic transsphenoidal approach, the authors demonstrated that this technique is generally safe and effective for different types of pediatric skull base lesions. Favorable effects of surgery were sustained during a follow-up period of 4 years. Further refinement in technology will allow for more widespread use in the pediatric population.

CSF leak after endoscopic skull base surgery in children: A single institution experience

INTRODUCTION

The endoscopic expanded endonasal approach (EEA) has been shown to be a safe and effective surgical technique in the resection of pediatric skull base lesions. Cerebrospinal fluid (CSF) leaks are among the most common complications of this approach. Here we review skull base resections using EEA in pediatric patients at our single institution, to identify potential risk factors for this surgical complication.

METHODS

A retrospective chart review was conducted on pediatric patients at our single institution for patients 19 years-old and under, who underwent an EEA for resection of a skull base tumor.

RESULTS

Thirty-nine pediatric patients (ages 1-19 years) with 8 different tumor pathologies underwent an EEA for resection of their skull base tumors. 21 patients experienced an intraoperative CSF leak, of which 10 (48%) were "high-flow" leaks and 11 (52%) were "low-flow" leaks. Nasoseptal flaps were only used to repair the intraoperative "high flow" leaks (n = 10), and "low flow" and "no leaks" were repaired with allograft and fat. No patients experienced a post-operative CSF leak.

CONCLUSION

In our pediatric series, the skull base repair algorithm of using an NSF only in cases of "high flow" intraoperative leaks was effective, and no post-operative CSF leaks occurred. Not using an NSF in cases of "low-flow" or "no leak" cases allows for decreased anatomical disruption in the growing patient.

Lessons learned in the evolution of endoscopic skull base surgery

OBJECTIVEEndoscopic skull base surgery (ESBS) is a relatively recent addition to the neurosurgical armamentarium. As with many new approaches, there has been significant controversy regarding its value compared with more traditional approaches to ventral skull base pathology. Although early enthusiasm for new approaches that appear less invasive is usually high, these new techniques require rigorous study to ensure that widespread implementation is in the best interest of patients.METHODSThe authors compared surgical results for ESBS with transcranial surgery (TCS) for several different pathologies over two different time periods (prior to 2012 and 2012-2017) to see how results have evolved over time. Pathologies examined were craniopharyngioma, anterior skull base meningioma, esthesioneuroblastoma, chordoma, and chondrosarcoma.RESULTSESBS offers clear advantages over TCS for most craniopharyngiomas and chordomas. For well-selected cases of planum sphenoidale and tuberculum sellae meningiomas, ESBS has similar rates of resection with higher rates of visual improvement, and more recent results with lower CSF leaks make the complication rates similar between the two approaches. TCS offers a higher rate of resection with fewer complications for olfactory groove meningiomas. ESBS is preferred for lower-grade esthesioneuroblastomas, but higher-grade tumors often still require a craniofacial approach. There are few data on chondrosarcomas, but early results show that ESBS appears to offer clear advantages for minimizing morbidity with similar rates of resection, as long as surgeons are familiar with more complex inferolateral approaches.CONCLUSIONSESBS is maturing into a well-established approach that is clearly in the patients' best interest when applied by experienced surgeons for appropriate pathology. Ongoing critical reevaluation of outcomes is essential for ensuring optimal results.

Long-term impact of pediatric endoscopic endonasal skull base surgery on midface growth

OBJECTIVE

Cranial base development plays a large role in anterior and vertical maxillary growth through 7 years of age, and the effect of early endonasal cranial base surgery on midface growth is unknown. The authors present their experience with pediatric endoscopic endonasal surgery (EES) and long-term midface growth.

METHODS

This is a retrospective review of cases where EES was performed from 2000 to 2016. Patients who underwent their first EES of the skull base before age 7 (prior to cranial suture fusion) and had a complete set of pre- and postoperative imaging studies (CT or MRI) with at least 1 year of follow-up were included. A radiologist performed measurements (sella-nasion [S-N] distance and angles between the sella, nasion, and the most concave points of the anterior maxilla [A point] or anterior mandibular synthesis [B point], the SNA, SNB, and ANB angles), which were compared to age- and sex-matched Bolton standards. A Z-score test was used; significance was set at p < 0.05.

RESULTS

The early surgery group had 11 patients, with an average follow-up of 5 years; the late surgery group had 33 patients. Most tumors were benign; 1 patient with a panclival arteriovenous malformation was a significant outlier for all measurements. Comparing the measurements obtained in the early surgery group to Bolton standard norms, the authors found no significant difference in postoperative SNA (p = 0.10), SNB (p = 0.14), or ANB (0.67) angles. The S-N distance was reduced both pre- and postoperatively (SD 1.5, p = 0.01 and p = 0.009). Sex had no significant effect. Compared to patients who had surgery after the age of 7 years, the early surgery group demonstrated no significant difference in pre- to postoperative changes with regard to S-N distance (p = 0.87), SNA angle (p = 0.89), or ANB angle (p = 0.14). Lesion type (craniopharyngioma, angiofibroma, and other types) had no significant effect in either age group.

CONCLUSIONS

Though our cohort of patients with skull base lesions demonstrated some abnormal measurements in the maxillary-mandibular relationship before their operation, their postoperative cephalometrics fell within the normal range and showed no significant difference from those of patients who underwent operations at an older age. Therefore, there appears to be no evidence of impact of endoscopic endonasal skull base surgery on craniofacial development within the growth period studied.

Endoscopic transnasal resection of optic pathway pilocytic astrocytoma

PURPOSE

Optic pathway gliomas (OPGs) are low-grade neoplasms that primarily affect children. The management of OPGs remains controversial. Reports on the use of the endoscopic endonasal approach (EEA) in OPGs are extremely limited, and no such reports exist on its utility for pediatric OPGs. Here, we report our results and experience with OPGs treated with the EEA.

METHODS

We retrospectively reviewed the medical records of OPG patients who were treated surgically via the EEA at our institutions from 2015 to 2017. Data on the demographics, clinical presentation, surgical complications, clinical outcomes, radiological imaging, and visual outcomes were recorded for each patient.

RESULTS

Four cases were identified, with visual disturbances being the predominant complaint. The mean patient age was 15.5 years. Three cases showed normal preoperative hormonal profiles, but one patient had hypothyroidism. All tumors identified in this study were World Health Organization grade I pilocytic astrocytomas. Surgical complications included hypopituitarism in two patients, meningitis in two patients, cerebrospinal fluid leak in one patient, and transient diabetes insipidus in one patient. No patient experienced worsening neurological or visual symptoms postoperatively.

CONCLUSIONS

Although our data are preliminary, the EEA provides a direct corridor to OPG with acceptable results in terms of tumor resection and visual outcomes. Hypothalamic-pituitary axis dysfunction remains a limitation of any treatment modality for OPGs and should be considered whenever possible. Definitive conclusions are pending as the learning curve of this approach is steep. Further work is needed to understand patient selection for such an approach.

Endoscopic Resection of Pediatric Skull Base Tumors: An Evidence-Based Review

Objectives  To perform a systematic review examining experiences with endoscopic resection of skull base lesions in the pediatric population, with a focus on outcomes, recurrence, and surgical morbidities. Methods  PubMed/MEDLINE, Cochrane Library, Embase, and Web of Science databases were evaluated. Studies were assessed for level of evidence. Bias risk was evaluated using the Cochrane Bias tool, Grades of Recommendation, Assessment, Development and Evaluation (GRADE), and Methodological Index for Non-Randomized Studies (MINORS) criteria. Patient characteristics, pathology, site of primary disease, presenting symptoms, stage, procedure specific details, and complications were evaluated. Results were reported using the Preferred Reporting Systems for Systematic Reviews and Meta-Analysis guidelines. Results  Ninety-three studies met criteria for inclusion, encompassing 574 patients with skull base tumors. The GRADE and MINORS criteria determined the overall evidence to be moderate quality. The most common benign and malignant pathologies included juvenile nasopharyngeal angiofibromas ( n  = 239) and chondrosarcomas ( n  = 11) at 41.6 and 1.9%, respectively. Of all juvenile nasopharyngeal angiofibroma tumors, most presented at stage IIIa and IIIb (25.8 and 27.3%, respectively). Nasal obstruction (16.5%) and headache (16.0%) were common symptoms at initial presentation. Surgical approaches included endoscopic endonasal ( n  = 193, 41.2%) and endoscopic extended transsphenoidal ( n  = 155, 33.1%). Early (< 6 weeks) and late (>6 weeks) complications included cerebrospinal fluid leak ( n  = 36, 17.3%) and endocrinopathy ( n  = 43, 20.7%). Mean follow-up time was 37 months (0.5-180 months), with 86.5% showing no evidence of disease and 2.1% having died from disease at last follow-up. Conclusion  Endoscopic skull base surgery has been shown to be a safe and effective method of treating a variety of pediatric skull base tumors. If appropriately employed, the minimally invasive approach can provide optimal results in the pediatric population.

Pediatric Endoscopic Endonasal Approaches for Skull Base Lesions in the Very Young: Is It Safe and Effective?

Introduction  The fully endoscopic expanded endonasal approach (EEA) has been shown to be safe and efficacious in pediatric patients. However, in the very young patient (ages six and under), the anatomical challenge of working through a small nasal corridor is problematic. The ability to repair the skull base and use a nasoseptal flap (NSF) has also been called into question. Here, we review skull base resections using EEA in patients aged 6 years and younger. Methods  A retrospective chart review was conducted on pediatric patients age 6 years and younger who underwent EEA skull base resections over a 3-year period (June 2014 through June 2017). Results  Eight children aged 6 and under with seven tumor pathologies underwent an EEA for the resection of their skull base tumors, with a mean follow-up of 1.45 years. Only chordoma cases required multiple-staged resections. There are no tumor recurrences to date. A high-flow intraoperative cerebrospinal fluid (CSF) leak was encountered in three cases, and there were no postoperative CSF leaks. CSF leaks were effectively repaired with NSFs. One patient suffered from postoperative hypopituitarism, one patient experienced recurrent epistaxis secondary to turbinate destruction by the tumor, and one patient expired 8 months postresection secondary to metastatic disease. Conclusion  In our case series, EEA for skull base tumors in children aged 6 and under was a safe and effective surgical approach. Skull base defects are able to be effectively addressed with typical repairs including NSFs. Larger studies are warranted to further investigate this technique in this pediatric population.

Open Approaches to the Anterior Skull Base in Children: Review of the Literature

Introduction  Skull base lesions in children and adolescents are rare, and comprise only 5.6% of all skull base surgery. Anterior skull base lesions dominate, averaging slightly more than 50% of the cases. Until recently, surgery of the anterior skull base was dominated by open procedures and endoscopic skull base surgery was reserved for benign pathologies. Endoscopic skull base surgery is gradually gaining popularity. In spite of that, open skull base surgery is still considered the "gold standard" for the treatment of anterior skull base lesions, and it is the preferred approach in selected cases. Objective  This article reviews current concepts and open approaches to the anterior skull base in children in the era of endoscopic surgery. Materials and Methods  Comprehensive literature review. Results  Extensive intracranial-intradural invasion, extensive orbital invasion, encasement of the optic nerve or the internal carotid artery, lateral supraorbital dural involvement and involvement of the anterior table of the frontal sinus or lateral portion of the frontal sinus precludes endoscopic surgery, and mandates open skull base surgery. The open approaches which are used most frequently for surgical resection of anterior skull base tumors are the transfacial/transmaxillary, subcranial, and subfrontal approaches. Reconstruction of anterior skull base defects is discussed in a separate article in this supplement. Discussion  Although endoscopic skull base surgery in children is gaining popularity in developed countries, in many cases open surgery is still required. In addition, in developing countries, which accounts for more than 80% of the world's population, limited access to expensive equipment precludes the use of endoscopic surgery. Several open surgical approaches are still employed to resect anterior skull base lesions in the pediatric population. With this large armamentarium of surgical approaches, tailoring the most suitable approach to a specific lesion in regard to its nature, location, and extent is of utmost importance.

Endoscopic Management of Developmental Anomalies of the Skull Base

Developmental anomalies of the skull base may present in childhood or as an adult. The most common pathologies include dermoid, encephalocele, and glioma. Encephaloceles may present as part of a syndrome. Other entities include infantile hemangiomas and teratoma. Endoscopic techniques provide a less invasive and morbid option for treatment. Proper evaluation and treatment is necessary to prevent complications such as meningitis.