Application of skull base techniques to pediatric neurosurgery.

ABSTRACTBACKGROUND: Endoscopic transnasal surgery has gained rapid global acceptance over the last two decades. The growing literature and understanding of anterior skull base endoscopic anatomy, in addition to new dedicated endoscopic instruments and tools, have helped to expand the use of the transnasal route in skull base surgery.OBJECTIVE: Report our early experience in expanded endoscopic transnasal surgery (EETS) and approach to skull base neoplasms.DESIGN: Descriptive, retrospective case series.SETTING: Major tertiary care center.PATIENTS AND METHODS: A retrospective case review was conducted at King Saud University Medical City between December 2014 and August 2019. Cases with skull base neoplasms that underwent EETS were included. EETS was defined as endoscopic surgical exposure that extended beyond the sellar margins (prechiasmatic sulcus superiorly, clival recess inferiorly, cavernous carotid lines laterally). Routine transsphenoidal pituitary neoplasms, neoplasms of sinonasal origin and meningoencephaloceles were excluded.MAIN OUTCOME MEASURES: Preoperative clinical assessment, imaging results, surgical approach, and hospital course were all retrieved from the patient electronic charts. Clinical follow-up, perioperative complications, and gross residual tumor rates were documented and reviewed.SAMPLE SIZE AND CHARACTERISTICS: 45 cases of EETS, 13 males and 32 females with mean age of 39.0 (17.7) years (range 2–70 years).RESULTS: The series comprised a wide range of pathologies, including giant pituitary adenoma (8 cases), meningioma (23 cases), craniopharyngioma (4 cases), chordoma (4 cases), optic pathway glioma (2 cases), epidermoid neoplasms (2 cases), astrocytoma (1 case), and teratoma (1 case). For the entire series, gross total resection was achieved in 25/45 operations (55.5%). Postoperative cerebrospinal fluid leak was the most common complication observed in 9 patients (20%) which were all managed endoscopically. Major vascular complications occurred in 2 patients (4.4%) and are described. Other complications are outlined as well. No mortality was observed.CONCLUSIONS: EETS to the skull base can be done with results comparable to traditional approaches. More work is needed to expand our experience, improve outcomes, and educate the public and medical community in our region about the usefulness of this approach.LIMITATIONS: Sample size and study design.CONFLICT OF INTEREST: None.

Skull base tumors in children are rare but require complex approaches with potential morbidity to the developing craniofacial skeleton, in addition to tumor-related morbidity. Reports of long-term clinical and functional outcome following skull base approaches in children are scarce. The authors report long-term outcome in children with tumors undergoing multidisciplinary skull base surgery. A retrospective analysis was undertaken of children undergoing surgery at a single institution between 1998 and 2008 for benign and malignant lesions of the anterior, middle, or posterior cranial base. Patients with craniopharyngioma, pituitary tumors, and optic glioma were excluded. Histology, surgical morbidity, length of hospital stay, progression-free survival, and adjuvant therapy were recorded. Functional and cognitive outcome was assessed prospectively using the Late Effects Severity Score (LESS). Twenty-three children ranging in age from 13 months to 15 years underwent skull base approaches for resection of tumors during the study period. The median follow-up duration was 60 months. Tumor types included meningioma, schwannoma, rhabdomyosarcoma, neuroblastoma, angiofibroma, and chordoma. Complete resection was achieved in 12 patients (52%). Thirteen patients (57%) had benign histology. The median hospital stay was 7 days. There were 3 deaths, 1 perioperative and 2 from tumor progression. Two patients had CSF leakage (9%) and 2 developed meningitis. Two children (9%) had residual neurological deficit at last follow-up evaluation. Thirteen (59%) of 22 surviving patients received adjuvant therapy. The majority of the patients remain in mainstream education and 19 of the 20 surviving children have an LESS of 3 or lower. Children tolerate complex skull base procedures well, with minimal surgical-related morbidity as well as good long-term tumor control rates and functional outcomes from maximal safe resection combined with adjuvant treatment when required.

PurposePostoperative cerebrospinal fluid rhinorrhoea (CSFR) remains a frequent complication of endonasal approaches to pituitary and skull base tumours. Watertight skull base reconstruction is important in preventing CSFR. We sought to systematically review the current literature of available skull base repair techniques.MethodsPubmed and Embase databases were searched for studies (2000–2020) that (a) reported on the endonasal resection of pituitary and skull base tumours, (b) focussed on skull base repair techniques and/or postoperative CSFR risk factors, and (c) included CSFR data. Roles, advantages and disadvantages of each repair method were detailed. Random-effects meta-analyses were performed where possible.Results193 studies were included. Repair methods were categorised based on function and anatomical level. There was absolute heterogeneity in repair methods used, with no independent studies sharing the same repair protocol. Techniques most commonly used for low CSFR risk cases were fat grafts, fascia lata grafts and synthetic grafts. For cases with higher CSFR risk, multilayer regimes were utilized with vascularized flaps, gasket sealing and lumbar drains. Lumbar drain use for high CSFR risk cases was supported by a randomised study (Oxford CEBM: Grade B recommendation), but otherwise there was limited high-level evidence. Pooled CSFR incidence by approach was 3.7% (CI 3–4.5%) for transsphenoidal, 9% (CI 7.2–11.3%) for expanded endonasal, and 5.3% (CI 3.4–7%) for studies describing both. Further meaningful meta-analyses of repair methods were not performed due to significant repair protocol heterogeneity.ConclusionsModern reconstructive protocols are heterogeneous and there is limited evidence to suggest the optimal repair technique after pituitary and skull base tumour resection. Further studies are needed to guide practice.

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.

Endoscopic endonasal surgery for skull base tumors has advanced significantly, but postoperative cerebrospinal fluid (CSF) leak remains a significant concern. Introducing the vascularized pedicled nasoseptal flap (PNSF) has markedly reduced CSF leak rates, though outcomes remain variable across different studies. This systematic review and meta-analysis aimed to compare the efficacy of vascularized versus nonvascularized reconstruction techniques in these procedures.Three databases (PubMed, Cochrane, and Embase) were systematically searched to identify studies comparing CSF leak rates between PNSF and nonvascularized techniques for reconstruction after endoscopic endonasal skull base surgeries. It was designed according to the preferred reporting items for systematic reviews and meta-analyses reporting guidelines. Statistical analysis was performed using Review Manager, with heterogeneity evaluated via the I 2 statistic.After thorough selection, twenty articles were selected, and a total of 4,088 patients were included, of whom 1,851 were assigned to the nasoseptal flap group, and 2,237 were assigned to the no-flap group. The postoperative CSF leak ratio was significantly lower in the group that underwent reconstruction with PNSF compared with all the other grouped methods, respectively, 3.4 and 5.6% (odds ratio [OR]: 0.48; 95% confidence interval [CI]: 0.34–0.66; p < 0.00001; I 2 = 54%).Our results suggest that using the PNSF is associated with a lower incidence of postoperative CSF leak than other reconstruction techniques in endoscopic skull base surgeries and may be used for patients at risk of this complication.

ObjectiveVarious non-vascularized or vascularized techniques have been adopted in endoscopic endonasal surgery (EES) for repairing intraoperative cerebrospinal fluid (CSF) leaks after tumor resection. Vascularized nasoseptal flaps (VNSF), free nasoseptal grafts (FNSG), free turbinate grafts (FTG), fascia lata and mashed muscle (FLMM) are frequently used. Outcomes of those grafts applied in the defects of different regions need to be clarified. MethodsThe data from a series of 162 patients with skull base tumor who underwent EES that had intraoperative CSF leak between Jan 2012 and Jan 2021 were retrospectively analyzed. The regions included anterior skull base (ASB), sellar region, clivus and infratemporal fossa (ITF). Repair failure rate (RFR), meningitis rate and associated risk factors were assessed. ResultsIn total, 172 reconstructions were performed in 162 patients for the four sites of the skull base. There were 7 cases (4.3%) that had postoperative CSF leaks, which required second repair. The RFR for ASB, sellar region, clivus, and ITF was 2.6%, 2.2%, 16.7%, and 0%, respectively. The clivus defect was an independent risk factor for repair failure (P<0.01). The postoperative meningitis rate was 5.6%. Repair failure was an independent risk factor for meningitis (P < 0.01). ConclusionsVNSF, FNSG, FTG, FLMM are reliable autologous materials for repairing the dural defects in different regions during EES. Clivus reconstruction remains a great challenge, which had a higher RFR and meningitis rate. Repair failure is significantly associated with postoperative meningitis.

In recent years, resections of midline skull base tumors have been conducted using endoscopic endonasal skull base (EESB) approaches. Nevertheless, many surgeons reported that cerebrospinal fluid (CSF) leakage is still a major complication of these approaches. Here, we report the results of our 42 EESB surgeries and discuss the advantages and limits of this approach for resecting various types of tumors, and also report our technique to overcome CSF leakage. All 42 cases involved midline skull base tumors resected using the EESB technique. Dural incisions were closed using nasoseptal flaps and fascia patch inlay sutures. Total removal of the tumor was accomplished in seven pituitary adenomas (33.3%), five craniopharyngiomas (62.5%), five tuberculum sellae meningiomas (83.3%), three clival chordomas (100%), and one suprasellar ependymoma. Residual regions included the cavernous sinus, the outside of the intracranial part of the internal carotid artery, the lower lateral part of the posterior clivus, and the posterior pituitary stalk. Overall incidence of CSF leakage was 7.1%. Even though the versatility of the approach is limited, EESB surgery has many advantages compared to the transcranial approach for managing mid-line skull base lesions. To avoid CSF leakage, surgeons should have skills and techniques for complete closure, including use of the nasoseptal flap and fascia patch inlay techniques.

Cerebrospinal fluid (CSF) rhinorrhea is a consequence of a breakdown of the layers of the arachnoid membrane, dura matter, the bony skull base and periosteum, and the nasal mucosa.1 In the past few years, several endoscopic techniques have been described to close ventral skull base CSF leaks. These include local pedicled flaps (e.g., nasoseptal flap,2 turbinates3), regional pedicled flaps (e.g., pericranium,4 fascia temporalis5), free grafts (e.g., abdominal fat,6 fascia lata7), microanastomosed free flaps,8 as well as synthetic grafts.8 Nowadays, most authors use multiple-layer reconstruction by combining these techniques to improve the success rate of endoscopic skull base reconstruction. The choice of skull base reconstruction technique depends on the location and the size of the defect, as well as intracranial pressure. The graft can be placed in the extracranial or extradural spaces that are often used, or in the intradural space, which is technically more demanding. In cases of small-size CSF leaks, we propose a new surgical technique, with a good success rate, that allows centering the intradural graft adequately on the defect. This “parachute” placement can be used with both autologous free grafts and synthetic materials. A retrospective chart review was performed to identify patients who had undergone endoscopic-guided transnasal duraplasty for small low-flow CSF leaks (<2 cm) of the ventral skull base in the Lariboisière University Hospital in Paris, France. Leaks that were reconstructed with other techniques were excluded. We report on the surgical technique, graft materials, and outcomes. All patients were imaged preoperatively with skull base computed tomography and magnetic resonance imaging. The procedure (Supporting Video S1) is done under general anesthesia. The patient is positioned supine, with the patient's head in a neutral position. An anterior and posterior ethmoidectomy is performed, associated most often with a middle turbinate removal. Then, the CSF leak site is identified endoscopically and measured. Site preparation begins by removal of the overlying mucosa. Abrasion of the adjacent and involved bone is generally advocated to stimulate osteoneogenesis. If needed, the bone defect is enlarged to see the limits of the dura defect. Then, an intradural and extradural circular dissection is performed with angled elevators to allow an underlay and overlay placement of the graft. The parachute technique allows the use of both fascia lata and synthetic materials. We present here a skull base reconstruction of a 1.5-cm defect of the planum sphenoidale (Fig. 1). A Biodesign duraplasty graft (Cook Biotech, West Lafayette, IN) in a size that was approximatively 30% larger was designed. A nonabsorbable polypropylene suture (3/0) is passed through the graft near the center in a U shape (Fig. 2). The two strands must be long enough to easily exit the nose. Then, the graft is placed in the subdural space using classic microsurgical instruments (angled endonasal blunt hook and seeker, spoon curettes, blunt angled elevators). A slight tension on the strands allows centering the graft on the defect, and then it is applied against the dura without any pucker (Fig. 3), hence the name parachute technique. It should be noted that the role of the suture is not to anchor the graft but to center it on the defect. The graft is then covered with fibrin glue to seal the reconstruction and the suture is removed, with back pressure being maintained on the graft with a blunt instrument to avoid displacement (Fig. 4). Fibrin glue sealing should be used sparingly between the two reconstruction layers to avoid dead space during resorption. Then, a second graft designed like the first graft is placed in the extradural space, as a “sandwich” to maintain the dura between two graft layers. At the end of the procedure, fibrin glue sealant is applied (Fig. 5). With this parachute closure technique, it is possible to associate a multilayer reconstruction using a mucosal graft or mucosal flaps to cover the graft and surrounding bone. We did not use any nasal packing or postoperative antibiotics. Patients must follow common postoperative advice such as avoiding Valsalva-like maneuvers and do not strain. Acetazolamide was prescribed only in case of suspicion of intracranial hypertension. We did not use any lumbar drain. Sixteen patients were included in the study from 2005 to the present. All patients were operated on by the same surgeon (p.h.). The main results are summarized in Table 1. Iatrogenic CSF leaks were addressed by other centers and then closed during another surgical procedure. The mean postoperative follow-up was 24 months (range = 1–101 months). We did not notice any leak recurrence. It was difficult to find in our database all of the patients who were treated with the parachute technique, and we probably missed some. In addition, only 25% of the population described here had a spontaneous CSF leak, which is at higher risk of recurrence. However, in our mind, we did not notice any recurrence after this type of reconstruction, which is used for small defects of the ventral skull base, regardless of the medical history. Small CSF leaks are not so easy to close. Dot-shaped leaks are accessible through a simple bipolar cauterization of the dura mater and a common fibrin glue sealing. Then, a graft or flap can be used extracranially to secure the repair. If the dura defect is greater than a few millimeters, this technique may not be enough to achieve a watertight closure.9 Many techniques have been proposed with good results.10 Among them, we can cite the “bath-plug” reconstruction,11 which consists in introducing a fat plug intracranially, secured with a Vicryl suture into the intradural space, and placing traction to seal the defect. This is a unique layer transdural technique with some disadvantages. The amount of intracranial fat is difficult to quantify, the reconstruction is not anatomical as it does not reproduce the dura mater layer, and the Vicryl suture remains in the fat plug until its absorption. The sandwich technique12 requires the placement of a layer of fascia lata in the epidural space (first layer), then a layer of cartilage or bone fitted to close the bony defect (second layer), and finally another piece of fascia lata extracranially. In a comparison of these two techniques, the parachute closure allows an anatomical reconstruction of the dura mater and a guided healing of the dura defect between two layers of reconstruction material, with a complete removal of the suture at the end of the procedure. A third layer can also be placed (mucosal graft or mucosal flap) extracranially but is not mandatory. The gasket seal technique13 can also be used. It consists in an autologous fascia lata or synthetic graft used to create a gasket seal around a bone buttress, gently applying a countersunk on the bone graft into the defect. If the bone graft is not perfectly sized up, it can lead to a lack of support of the fascia lata (if too small) or in excessive force applied on the defect (too large). If the margins of leak are not surrounded by bone, this technique is not easy to achieve. Again, it is transdural and does not reproduce the anatomical layers. Furthermore, in cases of small defects, the gasket seal technique may require an enlargement of the primary defect so as to place the reconstruction. The parachute technique may also be used in second-intention surgeries in failures of skull base reconstruction, even after chemoradiotherapy (two patients in our experience). We believe that this technique can be part of a surgical arsenal for small CSF leaks closure, and that is complementary to the techniques already described. The surgical technique described here can be a suitable alternative to other closure techniques for small, first-intention CSF leaks of the ventral skull base and is a minimally invasive option for small CSF leak recurrences after oncologic resection. It allows a multilayer reconstruction in the intradural and extradural space to guide the healing of the dura mater. The authors gratefully acknowledge the technical support of Mr. Clément Jourdaine from the Otorhinolaryngology Department–Skull Base Center of Lariboisière Hospital, and Mrs. Pamela Combastet for the English-language editing. Video S1. Skull base reconstruction of a 1.5-cm defect of the planum sphenoidale using the “parachute” technique. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Endoscopic endonasal surgery is a well-established surgical approach to the skull base. Surgeons need a reusable long-lasting tool to acquire the skills needed for skull base reconstruction. The aim of this study was to elaborate and validate a human formalin-fixed cadaveric model that reproduces a realistic cerebrospinal fluid (CSF) circulation and that adequately renders a CSF leak. An external ventricular drain that connects with a peristaltic pump is placed in the subarachnoid space, which allows a water circulation that reproduces CSF circulation. Intracranial pressure is measured in real time. Endoscopic endonasal skull base approaches are performed, to create different skull base openings and CSF leaks. Participants were tasked with reconstruction of the defects using a standardized multilayered approach, with the goal of obtaining a watertight closure under normal intracranial pressure ranges. Compiled data included time of reconstruction, years of experience of participants, and success/failure to achieve a watertight reconstruction. A Likert questionnaire was also used. The cadaveric model reproduced CSF circulation in 4 types of dural defects: sellar, suprasellar, transcribriform, and transclival. Intracranial pressures were similar to physiological conditions and were reproducible. Each model was tested multiple times, over several months. Success rates concurred with training levels (r = .8282 and P = .0017). A strong inverse correlation was also found between years of experience and time of reconstruction (r = .4977 and P < .0001). Participants agreed that the model was realistic (median Likert score of 4), and they strongly agreed that it allowed for the improvement of their surgical skills (median Likert score of 5). This novel human-fixed cadaveric model for CSF circulation is efficient and adequately reproduces surgical conditions for skull base approaches. The model is unique, easy to reproduce, and reusable. It can be used as a tool for teaching and for research purposes.

Cerebrospinal fluid (CSF) rhinorrhea is a sign of a breach in the bony skull base. It should be verified, localized, and repaired surgically to alleviate the risk of intracranial infection. Endonasal endoscopic surgery is the standard technique for skull base reconstruction in these patients. The current study was undertaken to evaluate a large case series of patients with CSF rhinorrhea who underwent surgery, focusing on symptoms, etiology, specifics of skull base defects, reconstruction techniques, outcomes, and complications. All patients with CSF rhinorrhea who were treated endoscopically for a skull base defect from 2010 to 2023 in a tertiary referral hospital were included. In this retrospective study, 263 patients were included. The chief presenting symptom was rhinorrhea. Spontaneous CSF leak was the most common etiologic factor, whereas accidental trauma accounted for about one-third of the cases. In cases of spontaneous CSF rhinorrhea, the most common sites of skull base defects were the cribriform plate, lateral lamella of the ethmoid, and the lateral recess of the sphenoid. The frontal sinus was the most common site of defect in cases of accidental traumatic CSF rhinorrhea. In the majority of cases, a two-layer technique using inlay fat and onlay fascia was employed for skull base reconstruction. Recurrences, including technical failures, missed skull base defects, and late new skull base defects, were observed in 10 cases (3.8%). Three patients developed meningitis in the early postoperative period, but all recovered uneventfully. Given the high success rate and low morbidity, all patients with CSF rhinorrhea should be counseled to undergo endoscopic surgery early.

Background Prior studies showed that female patients with chronic rhinosinusitis (CRS) suffer a worse disease-specific quality of life (QoL). Goal The aim of this study is to investigate gender differences in sinonasal QoL outcomes in patients requiring endoscopic endonasal skull base surgeries (EESBS). Methods Cross-sectional analysis of patients presenting to our clinic from August 2020 to December 2022 with skull base tumors, spontaneous cerebrospinal fluid (CSF) rhinorrhea, or Grave's orbitopathy (for orbital decompression) was performed. Baseline and postsurgical QoL were measured using the 22-item Sinonasal Outcome Test (SNOT-22). Patients' demographics and comorbidities were reviewed. Patients with concomitant CRS were excluded. Results Eighty-six patients were included (54 with skull base tumors, 17 Grave's orbitopathy, and 15 spontaneous CSF rhinorrhea). The mean age of the patients was 52 years (range: 12.4-81.5 years), and 51.6% of the patients were females. There was no age difference between female and male patients. Smoking history, asthma, and allergic rhinitis were also similar between the two groups. Female patients had a significantly higher incidence of depression (58.3 vs. 32.4%, p = 0.018) and migraine (50.0 vs. 21.6%, p = 0.007). Female patients had a significantly worse overall SNOT-22 scores at baseline (33.6 vs. 18.2, p = 0.001), at the 3-month follow-up (29.7 vs. 15.5, p = 0.002), and at the 6-month follow-up (33.5 vs. 14.9, p = 0.005). This worse QoL was seen mainly in the ear/facial, sleep, and psychological domains. Linear regression of the SNOT-22 scores and its subdomains adjusting for comorbidities showed that migraine was found to be the most significant determinant of gender differences in the QoL. Conclusion Female patients who undergo EESBS show higher overall SNOT-22 scores secondary to higher incidence of migraine.

Skull fractures are common after blunt pediatric head trauma. CSF leaks are a rare but serious complication of skull fractures; however, little evidence exists on the risk of developing a CSF leak following skull fracture in the pediatric population. In this epidemiological study, the authors investigated the risk factors of CSF leaks and their impact on pediatric skull fracture outcomes. The authors queried the MarketScan database (2007-2015), identifying pediatric patients (age < 18 years) with a diagnosis of skull fracture and CSF leak. Skull fractures were disaggregated by location (base, vault, facial) and severity (open, closed, multiple, concomitant cerebral or vascular injury). Descriptive statistics and hypothesis testing were used to compare baseline characteristics, complications, quality metrics, and costs. The authors identified 13,861 pediatric patients admitted with a skull fracture, of whom 1.46% (n = 202) developed a CSF leak. Among patients with a skull fracture and a CSF leak, 118 (58.4%) presented with otorrhea and 84 (41.6%) presented with rhinorrhea. Patients who developed CSF leaks were older (10.4 years vs 8.7 years, p < 0.0001) and more commonly had skull base (n = 183) and multiple (n = 22) skull fractures (p < 0.05). These patients also more frequently underwent a neurosurgical intervention (24.8% vs 9.6%, p < 0.0001). Compared with the non-CSF leak population, patients with a CSF leak had longer average hospitalizations (9.6 days vs 3.7 days, p < 0.0001) and higher rates of neurological deficits (5.0% vs 0.7%, p < 0.0001; OR 7.0; 95% CI 3.6-13.6), meningitis (5.5% vs 0.3%, p < 0.0001; OR 22.4; 95% CI 11.2-44.9), nonroutine discharge (6.9% vs 2.5%, p < 0.0001; OR 2.9; 95% CI 1.7-5.0), and readmission (24.7% vs 8.5%, p < 0.0001; OR 3.4; 95% CI 2.5-4.7). Total costs at 90 days for patients with a CSF leak averaged $81,206, compared with $32,831 for patients without a CSF leak (p < 0.0001). The authors found that CSF leaks occurred in 1.46% of pediatric patients with skull fractures and that skull fractures were associated with significantly increased rates of neurosurgical intervention and risks of meningitis, hospital readmission, and neurological deficits at 90 days. Pediatric patients with skull fractures also experienced longer average hospitalizations and greater healthcare costs at presentation and at 90 days.

Skull base approaches to complex cerebral aneurysms

The techniques of skull base surgery attempt to maximize the exposure of a cranial base lesion while using the least amount of brain retraction. Cranial base surgery is not a 'new' area of neurosurgical or otolaryngologic interest, but instead represents a resurgence of efforts to treat difficult lesions involving the cranial base. This resurgence of interest and effort is a product of recent advances in microanatomical knowledge of the cranial base, advances in microsurgical technique, improved neurophysiologic monitoring, and improved collaborative relationships between neurosurgery, otolaryngology and plastic surgery. Furthermore, improved neuroanesthetic techniques allow the surgeon to proceed with surgery without undue concern about time, and improved neuroimaging techniques provide the surgeon with detailed knowledge of the three dimensional characteristics of the tumor and surrounding structures. This review will focus on the surgical management of cranial base tumors primarily affecting the pediatric population. Little has been written on the techniques of skull base surgery as they apply to the pediatric population, since cranially-based tumors are a relatively rare occurrence in this patient population. In most instances, however, many of the 'standard' skull base approaches can be applied to the pediatric patient with few modifications, and in our experience, the pediatric patients have tolerated these approaches as well as their adult counterparts.

Mandibular access osteotomy: Gate way to parapharyngeal space – A case report