Showing papers in "Skull Base Surgery in 2017"

Diabetes Insipidus following Endoscopic Transsphenoidal Surgery for Pituitary Adenoma.

Abstract: Objectives Pituitary adenoma (PA), among the most commonly encountered sellar pathologies, accounts for 10% of primary intracranial tumors. The reported incidence of postoperative diabetes insipidus (DI) is highly variable. In this study, we report our experience with DI following endoscopic transsphenoidal surgery (TSS) for PAs, elucidating the risk factors of postoperative DI, the likelihood of long-term DI, and the impact of DI on the length of stay (LOS). Methods The study included 178 patients who underwent endoscopic resection of PAs. Early DI was defined as that occurring within the first postoperative week. The mean follow-up was 36 months. Long-term DI was considered as DI apparent in the last follow-up visit. Results Of the 178 patients included in the study, 77% of the tumors were macroadenomas. Forty-seven patients (26%) developed early DI. Long-term DI was observed in 18 (10.1%) of the full cohort. Age younger than 50 years was significantly associated with a higher incidence of long-term DI (p = 0.02). Macroadenoma and gross total resection were significantly associated with higher incidence of early DI (p = 0.05 and p = 0.04, respectively). The mean LOS was 4 days for patients with early postoperative DI and 3 days for those without it. Conclusion The reported incidence of postoperative DI is significantly variable. We identified age younger than 50 years a risk factor for developing long-term postoperative DI. Gross total surgical resection and tumor size (> 1 cm) were associated with development of early DI. Early DI increased the LOS on average by 1 day.

Targeted Epidural Blood Patch Treatment for Refractory Spontaneous Intracranial Hypotension in China.

Abstract: Objective An epidural blood patch (EBP) is the mainstay of treatment for refractory spontaneous intracranial hypotension (SIH). We evaluated the treatment efficacy of targeted EBP in refractory SIH. Methods All patients underwent brain magnetic resonance imaging (MRI) with contrast and heavily T2-weighted spine MRI. Whole spine computed tomography (CT) myelography with non-ionic contrast was performed in 46 patients, and whole spine MR myelography with intrathecal gadolinium was performed in 119 patients. Targeted EBPs were placed in the prone position one or two vertebral levels below the cerebrospinal fluid (CSF) leaks. Repeat EBPs were offered at 1-week intervals to patients with persistent symptoms, continued CSF leakage, or with multiple leakage sites. Results Brain MRIs showed pachymeningeal enhancement in 127 patients and subdural hematomas in 32 patients. One hundred fifty-two patients had CSF leakages on heavily T2-weighted spine MRIs. CSF leaks were also detected on CT and MR myelography in 43 and 111 patients, respectively. Good recovery was achieved in all patients after targeted EBP. No serious complications occurred in patients treated with targeted EBP during the 1 to 7 years of follow-up. Conclusions Targeted and repeat EBPs are rational choices for treatment of refractory SIH caused by CSF leakage.

Role of Adjuvant Treatment in Sinonasal Mucosal Melanoma.

Abstract: Purpose Sinonasal mucosal melanoma (SNMM) is a locally aggressive tumor. This study aimed to define the role of adjuvant treatment and its association with survival outcomes of SNMM. Methods This retrospective study investigated 152 patients with SNMM treated between 1991 and 2016 in MD Anderson Cancer Center. Patients were divided into the following treatment groups: surgery alone, surgery with postoperative radiotherapy (PORT), surgery with postoperative chemoradiation (POCRT), and induction chemotherapy followed by surgery and PORT. Overall survival (OS), disease-specific survival, and relapse-free survival were compared. Survival between the groups was compared using univariate and multivariate analyses. Results The median follow-up was 28 months (range: 2–220 months). Five-year OS rates were 39, 42, 47, and 27% for the surgery only, PORT, POCRT, and neoadjuvant chemotherapy groups, respectively (log rank p = 0.73). Distant metastasis was the most common form of treatment failure and occurred in 59 (39%) patients. Five-year distant metastasis rates were 51, 45, and 58% for patients treated with surgery alone, PORT, and POCRT, respectively (log rank p = 0.21) but unable to be estimated in the neoadjuvant chemotherapy group due to low OS rates. Multivariate analysis demonstrated tumor site (hazard ratio [HR] = 2.32, 95% confidence interval [CI] = 1.24–4.15) and smoking status (HR = 1.77, 95% CI = 1.02–3.1) to be significant prognostic factors for survival. Conclusion Tumor site and smoking status were significant prognosticators in SNMM. A high rate of distant metastatic disease suggests that further investigation into novel, systemic therapies is required to improve outcomes in this disease entity.

Injury of the Carotid Artery during Endoscopic Endonasal Surgery: Surveys of Skull Base Surgeons.

Abstract: Objectives This study aimed to review endoscopic skull base surgeon experience with internal carotid artery (ICA) injuries during endoscopic endonasal surgery (EES) to provide an estimate of the incidence of ICA injury, the associated factors and identify the best training modalities for the management of this complication. Design Anonymous electronic survey of past participants at a well-established endoscopic skull base surgery course and a global online community of skull base surgeons. Main Outcome Measures Relative incidence of ICA injuries during EES, associated anatomic and intraoperative factors, and surgeon experience. Results At least 20% of surgeons in each surveyed population experienced a carotid artery injury. Reported carotid artery injuries were most common during tumor exposure and removal (48%). The parasellar carotid artery was the most commonly injured segment (39%). Carotid artery injuries were more common in high-volume surgeons, but only statistically significant in one of the two populations. Attendance at a skull base course or courses did not change the incidence of carotid artery injury in either surveyed population. In both surveys, respondents preferred live surgeries or active (not computer simulated) training models. Conclusions ICA injury is underreported and most common when manipulating the parasellar carotid artery for exposure and tumor dissection. Given the high morbidity and mortality associated with these injuries, vascular injury management should be prioritized and taught in a graduated approach by modern endoscopic skull base courses.

A Cross-sectional Survey of the North American Skull Base Society: Current Practice Patterns of Vestibular Schwannoma Evaluation and Management in North America.

Abstract: Background Very few studies have examined vestibular schwannoma (VS) management trends across centers and between providers. The objective of this study is to examine current practice trends, variance in treatment philosophies, and nuanced or controversial aspects of VS care across North America. Methods This is a cross-sectional survey of North American Skull Base Society (NASBS) members who report regular involvement in VS care. Results A total of 57 completed surveys were returned. Most respondents claimed to have over 20 years of experience and the majority reported working in an academic practice with an affiliated otolaryngology and/or neurosurgery residency program. Sixty-three percent of respondents claimed to evaluate VS patients in clinic with both an otolaryngologist and neurosurgeon involved. Eighty-six percent of respondents claimed to operate on VS with both an otolaryngologist and neurosurgeon involved, while only 18% of neurosurgeons and 9% of otolaryngologists performed surgery alone. There was a wide range in the number of cases evaluated at each center annually. Similarly, there was wide variation in the number of patients treated with microsurgery and radiation at each center. Additional details regarding management preferences for microsurgery, stereotactic radiosurgery, stereotactic radiotherapy, and conservative observation are presented. Conclusion VS management practices vary between providers and centers. Overall, most centers employ a multidisciplinary approach to management with collaboration between otolaryngology and neurosurgery. Overall, survey responses concur with previous studies suggesting a shift toward conservatism in management.

An Algorithm for Sellar Reconstruction Following the Endoscopic Endonasal Approach: A Review of 300 Consecutive Cases.

Abstract: Objectives/Hypotheses The endoscopic endonasal approach (EEA) is the workhorse endoscopic procedure for sellar and parasellar pathology. Various reconstruction techniques have been reported following EEA surgery, ranging from no reconstruction to vascularized flaps. We review our institution's experience with sellar reconstruction following EEA and propose an evidence-based algorithm. Design Retrospective review. Setting Tertiary academic medical center. Participants Patients who underwent endoscopic EEA surgery for sellar or parasellar pathology between March 1, 2013 and August 31, 2016. Main Outcome Measures Patient demographic and clinicopathologic data were collected. Outcome measures included intraoperative and postoperative cerebrospinal fluid (CSF) leak rates and extent of resection (gross or subtotal). Results Three hundred consecutive patients were included. Depending on the presence and grade of intraoperative CSF leak, cases were reconstructed using either a free mucosal graft (FMG) or nasoseptal flap (NSF). Intraoperative and postoperative CSF leak rates were 30.7% and 2.3%, respectively. Multivariable logistic regression found that intraoperative CSF leak was associated with recurrent disease (odds ratio [OR] 2.47, p = 0.004), with no apparent predictors of postoperative CSF leak. Conclusions Based on this large series, we propose the following algorithm for sellar reconstruction: FMG for no CSF leak; fat graft + FMG ± rigid fixation for low-grade leaks; and fat graft + NSF ± rigid fixation for high-grade leaks.

Spontaneous Cerebrospinal Fluid Rhinorrhea: Association with Body Weight and Imaging Data.

Abstract: Objective Spontaneous cerebrospinal fluid rhinorrhea (SCSFR) might be the only clinical manifestation of idiopathic intracranial hypertension (IIH), which has been historically related to overweight. Our goal was to search for an association between SCSFR and increased body weight on the one hand and SCSFR and imaging findings suggestive of IIH on the other hand. Materials and Methods We retrospectively collected clinical and radiological data of patients operated on endoscopically for SCSFR in our institution from 1993 to 2013. Analyzed factors were body mass index (BMI), extended sphenoid sinus pneumatization on computed tomography, and empty sella and distention of the optic nerve sheath on magnetic resonance imaging. Results There were 15 patients: 8 females/7 males; mean age 50 years. Primary surgical success rate was 86.7%. Regarding body weight, 80% were overweight (BMI ≥ 25) versus 32% in the French general population (p Conclusion We found statistically significant associations between SCSFR and overweight, increased pneumatization of sphenoid sinuses, empty sella, and dilation of optic nerve sheath, but not with obesity, which did not have any additional impact of CSF leak than did overweight.

Pathogenetic Analysis of Sinonasal Teratocarcinosarcomas Reveal Actionable β-catenin Overexpression and a β-catenin Mutation

Abstract: Objective Sinonasal teratocarcinosarcomas are rare, aggressive tumors of the skull base. Treatment options are limited and outcomes are poor. Little is known in regard to the genetic factors regulating these tumors. Characterization of actionable molecular alterations in these tumors could provide potentially successful therapeutic options. Methods We performed targeted exome sequencing on an index sinonasal teratocarcinosarcoma specimen to identify potential driver mutations. We performed immunohistochemical stains for β-catenin on paraffin-embedded tissue on the index tumor and a subsequent teratocarcinosarcoma. Online databases of cancer mutations (Catalogue of Somatic Mutations in Cancer and The Cancer Genome Atlas) were accessed. Results We identified an activating p.S45F mutation in β-catenin in our index sinonasal teratocarcinosarcoma. This mutation results in constitutive signaling in the Wnt/β-catenin pathway. We confirmed β-catenin overexpression and nuclear localization via immunohistochemistry in the index tumor and a second patient. The p.S45F activating mutation was found in a variety of solid tumors, and accounts for 3.3 to 10.4% of all known β-catenin mutations. Conclusion We identified a potential driver mutation in β-catenin in a sinonasal teratocarcinosarcoma, resulting in β-catenin overexpression. These findings suggest a role for the Wnt/β-catenin pathway in sinonasal teratocarcinosarcoma tumorigenesis and a role for anti-β-catenin targeted therapy.

A Comparative Analysis of Endoscopic-Assisted Transoral and Transnasal Approaches to Parapharyngeal Space: A Cadaveric Study.

Abstract: Background Surgical resection of parapharyngeal space (PPS) tumors is very challenging. An endoscopic-assisted surgical approach to this region requires detailed and precise anatomic knowledge. The main purpose of this study is to describe and compare the detailed anatomy of the PPS via transnasal transpterygoid (TP) and endoscopic-assisted transoral (TO) approaches. Materials and Methods Six fresh injected cadaver heads (12 sides) were prepared for dissection of the PPS via TP and TO approaches. Computed tomography (CT) with image-based navigation (Navigation System II; Stryker, Kalamazoo, Michigan, United States) was used to identify bony structures around the PPS. Results TP and TO approaches could both expose the detailed anatomical structures in the PPS. The TP approach can provide a direct route to the upper PPS, but it is limited inferiorly by the hard palate and laterally by the medial and lateral pterygoid muscles. However, the TO approach can provide a direct route to the lower PPS, but it is difficult to expose the area around the Eustachian tube. The styloglossus and stylopharyngeus muscles could be considered as the safe anterior boundary of the parapharyngeal internal carotid artery (ICA) with the TO approach. Dissection between the stylopharyngeus muscle and the superior pharyngeal constrictor muscle provides direct access to the parapharyngeal ICA. Conclusion The TP and TO approaches provide new strategies to manage lesions in the PPS. The important neurovascular structures of the PPS could be identified with these approaches. The endoscopic-assisted TO approach can provide direct access to the parapharyngeal ICA.

Using a Guided Machine Learning Ensemble Model to Predict Discharge Disposition following Meningioma Resection.

Abstract: Objective Machine learning (ML) algorithms are powerful tools for predicting patient outcomes. This study pilots a novel approach to algorithm selection and model creation using prediction of discharge disposition following meningioma resection as a proof of concept. Materials and Methods A diversity of ML algorithms were trained on a single-institution database of meningioma patients to predict discharge disposition. Algorithms were ranked by predictive power and top performers were combined to create an ensemble model. The final ensemble was internally validated on never-before-seen data to demonstrate generalizability. The predictive power of the ensemble was compared with a logistic regression. Further analyses were performed to identify how important variables impact the ensemble. Results Our ensemble model predicted disposition significantly better than a logistic regression (area under the curve of 0.78 and 0.71, respectively, p = 0.01). Tumor size, presentation at the emergency department, body mass index, convexity location, and preoperative motor deficit most strongly influence the model, though the independent impact of individual variables is nuanced. Conclusion Using a novel ML technique, we built a guided ML ensemble model that predicts discharge destination following meningioma resection with greater predictive power than a logistic regression, and that provides greater clinical insight than a univariate analysis. These techniques can be extended to predict many other patient outcomes of interest.

Minimally Invasive Surgery for Resection of Parapharyngeal Space Tumors.

Abstract: Background Surgical removal of parapharyngeal space tumors (PPST) poses challenges due to the complex anatomy of the region. PPSTs are routinely resected by a transcervical approach using blind finger dissection. Large PPSTs or those located high at the skull base, often require transmandibular or infratemporal fossa approaches, associated with considerable morbidity. Objective Here, we describe an approach for PPST removal that comprises transcervical endoscopic, with or without transoral robotic technique. Materials and Methods We retrospectively studied the demographic, clinical, surgical, and outcome data of 11 consecutive patients who underwent PPST excision between June 2013 and July 2017 at our center. Patients either underwent a transcervical endoscopic procedure ( n = 4), a transoral robotic procedure ( n = 2) or a combination of the two procedures ( n = 5). Results Complete tumor excision was achieved in all cases, with no intra-, peri-, or postoperative complications. Final histopathologic findings demonstrated pleomorphic adenoma for seven patients, cavernous hemangioma for one patient, and malignant tumors for three patients. The average tumor size was 44.22 ± 31.9 cm 3 (range: 7.5-111 cm 3 ). At follow-up (range: 3-42 months), there was no evidence of recurrence. Conclusions The approach described provides improved visualization and safe vascular control with minimum tumor stress, preventing the need for blind finger dissection, and allowing complete tumor removal while minimizing tumor spillage, nerve injury, and blood loss, maintaining excellent cosmetic and functional results. This approach could be utilized for the removal of large benign PPST, or small PPST located high.

Petroclival Meningiomas: Factors Determining the Choice of Approach

Abstract: Objectives To review a surgical series of petroclival meningiomas and the factors considered in the choice of approach. Design Retrospective review. Setting The study was conducted in a university hospital in southern Brazil. Participants Twenty-two patients with petroclival meningioma originating from the upper two-thirds of the clivus medial to the fifth cranial nerve. Main Outcome Measures Gross-total resection, mortality, major morbidity, new cranial nerve deficits and tumor progression or recurrence. Results Retrosigmoid approach was used in tumors Conclusions Resection of petroclival meningiomas remains challenging. In most cases, the retrosigmoid approach was sufficient, without affecting the degree of tumor resection. Petrosal approaches were reserved for patients with tumor extension into the middle fossa.

An Innovate Robotic Endoscope Guidance System for Transnasal Sinus and Skull Base Surgery: Proof of Concept

Abstract: Objective Advanced transnasal sinus and skull base surgery remains a challenging discipline for head and neck surgeons. Restricted access and space for instrumentation can impede advanced interventions. Thus, we present the combination of an innovative robotic endoscope guidance system and a specific endoscope with adjustable viewing angle to facilitate transnasal surgery in a human cadaver model. Materials and Methods The applicability of the robotic endoscope guidance system with custom foot pedal controller was tested for advanced transnasal surgery on a fresh frozen human cadaver head. Visualization was enabled using a commercially available endoscope with adjustable viewing angle (15–90 degrees). Results Visualization and instrumentation of all paranasal sinuses, including the anterior and middle skull base, were feasible with the presented setup. Controlling the robotic endoscope guidance system was effectively precise, and the adjustable endoscope lens extended the view in the surgical field without the common change of fixed viewing angle endoscopes. Conclusion The combination of a robotic endoscope guidance system and an advanced endoscope with adjustable viewing angle enables bimanual surgery in transnasal interventions of the paranasal sinuses and the anterior skull base in a human cadaver model. The adjustable lens allows for the abandonment of fixed-angle endoscopes, saving time and resources, without reducing the quality of imaging.

Cavernous Sinus Involvement by Pituitary Adenomas: Clinical Implications and Outcomes of Endoscopic Endonasal Resection.

Abstract: Background Parasellar invasion of pituitary adenomas (PAs) into the cavernous sinus (CS) is common. The management of the CS component of PA remains controversial. Objective The objective of this study was to analyze CS involvement in PA treated with endoscopic endonasal approaches, including incidence, surgical risks, surgical strategies, long-term outcomes, and our treatment algorithm. Methods We reviewed a series of 176 surgically treated PA with particular attention to CS involvement and whether the CS tumor was approached medial or lateral to the internal carotid artery. Results The median duration of follow-up was 36 months. Macroadenomas and nonfunctional adenomas represented 77 and 60% of cases, respectively. CS invasion was documented in 23% of cases. CS involvement was associated with a significantly diminished odds of gross total resection (47 vs. 86%, odds ratio [OR]: 5.2) and increased the need for subsequent intervention (4 vs. 40%, OR: 14.4). Hormonal remission was achieved in 15% of hormonally active tumors. Rates of surgical complication were similar regardless of CS involvement. Conclusion Our tailored strategy beginning with a medial approach and adding lateral exposure as needed resulted in good outcomes with low morbidity in nonfunctional adenomas. Functional adenomas involving the CS were associated with low rates of hormonal remission necessitating higher rates of additional treatment.

Preoperative Embolization for Skull Base Meningiomas.

Abstract: The results of preoperative embolization for skull base meningiomas were retrospectively evaluated to confirm the efficacy of this procedure. Skull base meningiomas that were treated with preoperative embolization were evaluated in 20 patients. The occluded arteries, embolic materials, treatment time, excision rate, neurologic manifestations, and complications were analyzed. The embolic material was 80% liquid, 30% coils, and 15% particles. The surgery was normally completed within 3 to 5 hours. Blood loss was normally approximately 250 mL, excluding four patients having the following conditions: malignant meningioma, a large tumor located on the medial side of the sphenoidal ridge, the petroclival tumor, and infiltrated tumor into the sigmoid sinus. The mean excision rate was 90%, achieving a Simpson grade III, but 10% were graded as Simpson grade IV. No permanent complications due to the preoperative embolization occurred. No neurologic symptoms occurred after excision. Current cerebral endovascular treatment is sophisticated, and the complication rate has markedly decreased. Although it was impossible to compare directly with or without operative embolization, preoperative embolization should be actively used as part of the treatment for this benign tumor, with better understanding of dangerous anastomosis.

Rater Reliability of the Hardy Classification for Pituitary Adenomas in the Magnetic Resonance Imaging Era

Abstract: Objectives The Hardy classification is used to classify pituitary tumors for clinical and research purposes. The scale was developed using lateral skull radiographs and encephalograms, and its reliability has not been evaluated in the magnetic resonance imaging (MRI) era. Design Fifty preoperative MRI scans of biopsy-proven pituitary adenomas using the sellar invasion and suprasellar extension components of the Hardy scale were reviewed. Setting This study was a cohort study set at a single institution. Participants There were six independent raters. Main Outcome Measures The main outcome measures of this study were interrater reliability, intrarater reliability, and percent agreement. Results Overall interrater reliability of both Hardy subscales on MRI was strong. However, reliability of the intermediate scores was weak, and percent agreement among raters was poor (12–16%) using the full scales. Dichotomizing the scale into clinically useful groups maintained strong interrater reliability for the sellar invasion scale and increased the percent agreement for both scales. Conclusion This study raises important questions about the reliability of the original Hardy classification. Editing the measure to a clinically relevant dichotomous scale simplifies the rating process and may be useful for preoperative tumor characterization in the MRI era. Future research studies should use the dichotomized Hardy scale (sellar invasion Grades 0–III versus Grade IV, suprasellar extension Types 0–C versus Type D).

Costs and Perioperative Outcomes Associated with Open versus Endoscopic Resection of Sinonasal Malignancies with Skull Base Involvement.

Abstract: Objective To compare financial and perioperative outcomes between endoscopic and open surgical approaches in the surgical management of sinonasal malignancies. Design Retrospective chart review. Setting Tertiary care hospital. Participants Patients undergoing surgical resection of a sinonasal malignancy from January 2000 to December 2014. Main Outcome Measures In-hospital costs, complications, and length of stay (LOS). Results Of 106 patients, 91 received open surgery (19 free flap and 72 non-free flap) and 15 were treated with purely endoscopic approaches. Free flaps had a significantly higher average cost, operative time, and LOS compared to both non-free flap ( p < 0.001, < 0.001, and < 0.01) and endoscopic ( p = 0.01, 0.04, and < 0.01) groups. There were no significant differences in average costs between endoscopic and non-free flap groups ($19,157 vs. $14,806, p = 0.20) or LOS (5.7 vs. 6.4 days, p = 0.72). Compared with the non-free flap group, the endoscopic group had a longer average operative time (8.3 vs. 5.5 hours, p < 0.01) and higher rates of cerebrospinal fluid (CSF) leak (13 vs. 0%, p = 0.01) and intensive care unit (ICU) admission (80 vs. 36%, p < 0.01). Surgical approach (open vs. endoscopic) was not a significant predictor of any financial or perioperative outcome on multivariable analysis. Conclusion Hospital costs are comparable between endoscopic and open approaches when no free tissue reconstruction is required. Longer operative times, higher CSF leak rates, and our institutional protocol necessitating ICU admission for endoscopic cases may account for the failure to demonstrate cost savings with endoscopic surgery.

Rates and Locations of Regional Metastases in Sinonasal Malignancies: The Mayo Clinic Experience.

Abstract: Objectives The objective of this study was to identify factors that may influence the rate and location of regional metastasis in sinonasal malignancies (SNMs). Design This is a retrospective review. Setting This study was set at the single-institution tertiary referral center. Participants A total of 299 patients were treated for SNMs from 1994 to 2014. Main Outcome Measures The main outcome measures were incidence and distribution of regional metastases. Results Several histologic subtypes were treated, with squamous cell carcinoma (28.4%), esthesioneuroblastoma (18.1%), and mucosal melanoma (12.4%) being the most common. Of the 299 patients, 59 (19.7%) developed a regional metastasis, either at presentation or during follow-up. Higher cumulative incidence of regional metastases was significantly associated with histologic type ( p ≤0.001) and invasion of the dura ( p = 0.005), infratemporal fossa ( p = 0.036), orbit ( p = 0.020), or palate ( p = 0.016). Ipsilateral level II lymph nodes were the most commonly involved nodes. Contralateral regional metastases were associated with higher risk histologic types ( p = 0.005) and dural invasion ( p = 0.008). Parotid metastases were associated with invasion of the facial soft tissue ( p = 0.028), and retropharyngeal metastases were associated with invasion of the pterygoid plates and musculature ( p = 0.030). Conclusion Histologic type of SNM appears to be the most important factor in predicting the rate of regional metastases. Histologic type and invasion of certain neighboring structures may help define which lymphatic basins are at highest risk for metastasis.

Surgical Outcomes and Postoperative Management in Spontaneous Cerebrospinal Fluid Rhinorrhea.

Abstract: Background The etiology of spontaneous cerebrospinal fluid (CSF) rhinorrhea remains unknown, though emerging evidence suggests that this likely represents a variant of idiopathic intracranial hypertension. Long-term success rates for repair and postoperative management strategies remain variable. Methods Retrospective review of patients undergoing surgical management of spontaneous CSF rhinorrhea was conducted over a 5-year period. Analysis was performed to correlate recurrence with demographics and perioperative variables. Lumbar puncture usage and neuro-ophthalmological examinations in clinical management were also assessed. Results Forty-eight patients were included in the study. The mean age was 51.4 years with 94% females. Leaks were most commonly located in the sphenoid (43.8%) and cribriform region (33.3%). The most common findings on magnetic resonance imaging were empty sella (48%) and Meckel's cave diverticula (24%). Nine patients (18.8%) had recurrent CSF leaks. Six occurred >1 month postoperatively. Three had repeat endoscopic repairs, two received ventriculoperitoneal shunts, and one was managed with a lumbar drain, with overall success rate of 93.8%. Acetazolamide was utilized in 19 cases (39.6%) postoperatively. Overall, 59% of patients had elevated opening pressures on postoperative lumbar puncture (n = 32). Neuro-ophthalmology evaluated 28 patients; 25% had visual field deficits, and 7.1% had papilledema. Conclusions Management of spontaneous CSF leaks remains a significant challenge. Endoscopic repair is successful in most patients with little morbidity; however, postoperative management remains inconsistent, and further studies are warranted to establish consensus on post-surgical care. The association with elevated intracranial pressure and visual field deficits/papilledema suggests opening pressures, and neuro-ophthalmologic evaluation should be considered in the treatment algorithm.

Potential Surgical Exposure of the Parapharyngeal Internal Carotid Artery by Endonasal, Transoral, and Transcervical Approaches.

Abstract: Objectives Endoscopic and endoscopic-assisted approaches to the parapharyngeal space have been reported; however, their potential for vascular exposure has not been previously assessed. This study aims to compare the potential exposure and control of the parapharyngeal internal carotid artery (ppICA) via various approaches. Design and Main Outcome Measures Ten cadaveric specimens were dissected bilaterally, exposing the ppICA via endonasal, transoral, and transcervical approaches. Length of the exposed vessel and potential control were assessed (feasibility and time required to place an encircling suture). Results Endoscopic transoral and transcervical–transmandibular approaches expose a significantly longer segment of the ppICA (6.89 and 7.09 cm) than the transoral and endonasal approaches. Vascular control was achieved via endoscopic-endonasal, endoscopic-transoral, and open techniques in 121.6, 64.8, and 5.2 seconds, respectively. Conclusion Histopathology, goals of surgery, and familiarity of the surgeon with each technique may ultimately determine the choice of approach; however, this study suggests that exposure of the ppICA by endoscopic-assisted transoral approach is comparable to that of a transcervical–transmandibular approach. Vascular control was feasible under elective circumstances. However, the difficulty varied widely, potentially reflecting the challenges of controlling an injured ppICA. However, one must note that active bleeding obscures the surgical field in ways that may impair ppICA control. Furthermore, the results may not reflect clinical scenarios where tumor distorts the surgical field. Nonetheless, the study suggests that, in properly selected patients, the endoscopic-assisted transoral approach avoids problems associated with unsightly scars, mandibular osteotomy, and facial nerve manipulation, whereas, the transcervical–transmandibular approach offers the swiftest vascular control.

A Cross-sectional Survey of the North American Skull Base Society on Vestibular Schwannoma, Part 2: Perioperative Practice Patterns of Vestibular Schwannoma in North America.

Abstract: Introduction Perioperative care of vestibular schwannoma (VS) patients is extremely variable across surgeons and institutions making practice patterns difficult to standardize. No data currently exist detailing this practice variability. Methods The North American Skull Base Society membership was electronically surveyed regarding perioperative care of surgically operated VS patients. Results There were 87 respondents to the survey. Surgical positioning, surgical approach utilized, and perioperative medical adjuncts are quite variable. However, of those performing retrosigmoid approaches, 49% perform this in the supine position, while 33% use a park-bench position with only 2% using the sitting position. In those performing translabyrinthine approaches, 86% perform this in supine position. Although the use of neuromonitoring appears to be standard of care (98%), other than the seventh nerve, there is substantial variability between respondents regarding monitoring of additional cranial nerves. Postoperative antibiotics are used by 65%, postoperative steroids 81%, and postoperative chemical deep vein thrombosis prophylaxis in 68% of survey respondents. Conclusion Although the perioperative adjuncts to VS surgery are variable, there does appear to be a trend in common practice. Therefore, making surgeons aware of these trends may lead to standardized practice or alternatively trials of these variances to instruct which truly improve patient outcomes.

Age and Tumor Volume Predict Growth of Carotid and Vagal Body Paragangliomas.

Abstract: Objective Treatment for head and neck paragangliomas (HNGPL) can be more harmful than the disease. After diagnosis, an initial period of surveillance is often indicated, and surgery or radiotherapy is reserved for progressive disease. With the aim to optimize this “wait and scan” strategy, we studied growth and possible predictors. Design A retrospective cohort study was conducted. Setting This study was conducted at a tertiary referral center for patients with HNGPL. Methods Tumor volume was estimated for 184 SDHD-related carotid and vagal body paragangliomas using sequential magnetic resonance imaging. Cox regression was used to study predictors of tumor growth. Results The estimated fraction of growing tumors ranged from 0.42 after 1 year of follow-up to 0.85 after 11 years. A median growth rate of 10.4 and 12.0% per year was observed for carotid and vagal body tumors, respectively. Tumor location, initial volume, and age (p Conclusions We created a prediction model (available online), enabling a more individualized “wait and scan” strategy. The favorable natural course of carotid and vagal body paragangliomas was confirmed; although with long follow-up growth will be observed in most cases.

Indocyanine Green Fluorescence to Evaluate Nasoseptal Flap Viability in Endoscopic Endonasal Cranial Base Surgery.

Abstract: Objectives The pedicled nasoseptal flap (NSF) has dramatically reduced postoperative cerebrospinal fluid leakage following endoscopic endonasal approach (EEA) surgery. Although rare, its arterial supply may be damaged during harvest or may be preoperatively damaged for numerous reasons. Early recognition permits harvesting a contralateral flap before sacrificing its pedicle as part of the surgical exposure or use of an alternative flap. Design Technical feasibility study and case series. Setting Tertiary care university-associated medical center. Participants Five patients requiring an EEA with NSF reconstruction. Main Outcome Measures During NSF harvest, intravenous indocyanine green (IVICG) was administered, and a customized endoscopic system was used to visualize the emerging fluorescence. At the end of each case, just before final positioning of the NSF, additional IVICG was administered, and the custom endoscope was again introduced to evaluate fluorescence. Results In four patients, the entire NSF fluoresced brightly with IVICG on initial harvest and before final positioning. One patient showed heterogeneous fluorescence of the pedicle and distal parts of the NSF at both stages. All NSFs healed well without complication. Conclusion IVICG facilitates real-time evaluation NSF's arterial supply. This may provide early recognition of arterial compromise, allowing the harvest of alternate flaps or modification of surgery.

Macrophage Density Predicts Facial Nerve Outcome and Tumor Growth after Subtotal Resection of Vestibular Schwannoma.

Abstract: Introduction Vestibular schwannoma (VS) behavior following subtotal resection (STR) is highly variable. Overall progression rates have been reported as high as 44%, and optimal treatment is controversial. Correspondingly, identification of a reliable clinical or pathologic marker associated with progression after STR would help guide decision-making. Methods A prospectively maintained institutional VS registry from 1999 to 2014 was retrospectively reviewed for sporadic VS patients who underwent primary STR without preceding stereotactic radiosurgery (SRS) by a single neurosurgery-neurotology team. Primary endpoints included tumor progression and postoperative facial nerve function. Pathologic specimens were stained for Ki67, CD68, S100, and SOX10 and were quantitated by digital imaging analysis. Macrophage density was defined as the ratio of CD68+ macrophages to S100+ macrophages and Schwannian tumor cells. Clinical outcomes were correlated with pathologic markers. Results Forty-six patients met the study inclusion criteria. Thirteen (28%) progressed during a mean 57 months of follow-up (range 15–149). Favorable postoperative facial nerve function (House–Brackmann I–II) was achieved in 37 (80%). CD68+ cells were present at significantly higher concentrations in tumors that progressed (p = 0.03). Higher macrophage density was significantly associated with both tumor progression (p = 0.02) and unfavorable facial nerve function (p = 0.02). Ki67 percent positivity was not significantly associated with either primary endpoint (p = 0.83; p = 0.58). Conclusions Macrophage density may provide an important marker for individuals at the highest risk for progression of VS after STR, potentially prompting closer surveillance or consideration for upfront SRS following STR. This finding supports preceding conclusions that an intratumoral macrophage-predominant inflammatory response may be a marker for tumor growth and a potential therapeutic target.

Impact of Cochlear Dose on Hearing Preservation following Stereotactic Radiosurgery and Fractionated Stereotactic Radiotherapy for the Treatment of Vestibular Schwannoma.

Abstract: Objective The objective of this study was to examine the effect of cochlear dose on hearing preservation in stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (fSRT) for vestibular schwannoma (VS). Design This is a retrospective case–control study. Setting This study was completed at the Ronald Reagan UCLA Medical Center, a university-affiliated tertiary care center. Participants Patients who underwent SRS (marginal dose of 12 Gy) or fSRT (marginal dose of 50.4 Gy) procedures for VS were included in the study. Main Outcome Measures The main outcome measure was hearing preservation. Audiometric data, when available, were used to determine the level of hearing according to the Gardner Robertson scale. Results A total of 38 patients (14 SRS and 24 fSRT) were analyzed. SRS patients with decreased hearing received a significantly higher minimum cochlear dose (7.41 vs. 4.24 Gy, p = 0.02) as compared with those with stable hearing. In fSRT patients, there were no significant differences in cochlear dose for patients with decreased hearing as compared with those with stable hearing. For SRS patients, who received a minimum cochlear dose above 6 Gy, there was a significant risk of decreased hearing preservation (odds ratio: 32, p = 0.02). Conclusion Higher minimum cochlear dose was predictive of decreased hearing preservation following SRS. Though the study is low powered, the radiation dose to the cochlea should be a parameter that is considered when planning SRS or fSRT therapies for patients with VS.

Naso- or Orbitocutaneous Fistulas after Free Flap Reconstruction of Orbital Exenteration Defects: Retrospective Study, Systematic Review, and Meta-Analysis.

Abstract: Objective Naso- or orbitocutaneous fistula (NOF) is a challenging complication of orbital exenteration, and it often requires surgical repair. We sought to identify the incidence and risk factors for NOF after orbital exenteration. Study Design Retrospective chart review, systematic review, meta-analysis. Setting Tertiary care center. Participants Patients undergoing free flap reconstruction following orbital exenteration. Records were reviewed for clinicopathologic data, operative details, and outcomes. Main Outcome Measures Univariate analysis was used to assess risk factors for incidence of postoperative NOF. PubMed and Cochrane databases were searched for published reports on NOF after orbital exenteration. Rates of fistula and odds ratios for predictive factors were compared in a meta-analysis. Results Total 7 of 77 patients (9.1%) developed NOF; fistula formation was associated with ethmoid sinus involvement (p Conclusion Immediate postoperative wound complications and medial orbital wall resection increased the risk for NOF. On review and meta-analysis, reconstruction of orbital exenteration defects decreased the risk for fistula formation, but published series did not demonstrate a significant decrease in risk with free flaps compared with other methods of reconstruction.

Compartmental Endoscopic Surgical Anatomy of the Inferior Intraconal Orbital Space

Abstract: Objectives This study aims to define the endoscopic anatomy of inferior intraconal space, in terms of its neurovascular structures and relationship to fixed anatomic landmarks. Design A cadaveric anatomical study was conducted. Setting This study was conducted at an academic cranial base center. Participants Cadaveric subjects have been investigated. Main Outcome Measures After dissection of the inferior intraconal space, the number and position of ophthalmic artery (OA) and oculomotor nerve (OMN) branches to the inferior rectus muscle (IRM) were quantified relative to the fixed landmark of the posterior maxillary wall. The point where the OMN branch to the inferior oblique muscle (IOM) crossed the lateral IRM margin was quantified. Results A total of 18 OA branches were identified with a mean ± standard deviation of 2.6 ± 0.53 branches. The mean distance of the OA branch insertion from the posterior maxillary wall was 7.11 ± 5.65 mm. The average number of OMN branches to the IRM was 1.63 ± 0.74 with a mean insertion distance of 1.88 ± 1.89 mm. The OMN branch to the IOM crossed the lateral IRM margin 5.38 ± 5.42 mm from the posterior maxillary wall. Conclusions This cadaveric study quantifies the variability of two critical neurovascular structures salient to endoscopic approaches to the inferior intraconal space, the OMN, and OA contributions to the IRM. Knowledge of the interrelationship between these structures is essential in safe technique for dissection.

Prognostic Indices for Predicting Facial Nerve Outcome following the Resection of Large Acoustic Neuromas.

Abstract: This study analyzes the simple ratio of anterior-to-posterior extension of large (>2.5 cm) acoustic neuromas relative to the internal auditory canal (ICA; anterior–posterior [A/P] index) as a tool for predicting risk of facial nerve (FN) injury. In total, 105 patients who underwent microsurgical resection for large acoustic neuromas were analyzed retrospectively. House–Brackmann (HB) scores were assessed immediately postoperatively, at 1 month, and at 1 year. Lateral–medial, inferior–superior, A/P, and maximum diameters were measured from preoperative magnetic resonance images. These measurements and the A/P index were analyzed using univariable and multivariable statistical models to assess relationship to FN outcomes. The retrosigmoid, translabyrinthine, and combined approaches were used, and the extent of resection was evaluated. For every 1 standard deviation increase in the A/P index, a patient was 3.87 times more likely have a higher postoperative HB score (p

Intracranial Hemangiopericytomas: Recurrence, Metastasis, and Radiotherapy.

Abstract: Background Intracranial hemangiopericytomas (HPCs) are characterized by high recurrence rates and extracranial metastases. Radiotherapy provides an adjunct to surgery, but the timing of therapy and the patients most likely to benefit remain unclear. Methods A retrospective review of 20 patients with HPC treated at the University of Texas Southwestern Medical Center between 1985 and 2014 was conducted. Recurrence and metastasis rates along with overall survival (OS) were characterized based on therapeutic approach and tumor pathology using Kaplan-Meier and Cox regression analyses. Results The mean age was 45.6 years (range: 19–77). Gross total resection (GTR) was achieved in 13 patients, whereas 5 patients underwent subtotal resection. Median follow-up was 91.5 months (range: 8–357). The 5-, 10-, and 15-year recurrence-free survival (RFS) rates were 61, 41, and 20%, respectively. Six patients developed metastases at an average of 113 months (range: 42–231). OS at last follow-up was 80%. Importantly, immediate postoperative adjuvant radiotherapy (IRT) did not influence RFS compared with surgery alone or OS compared with delayed radiotherapy at the time of recurrence. Conclusion HPCs have high recurrence rates necessitating close follow-up. Surgery remains an important first step, but the timing of radiotherapy for optimal control and OS remains uncertain.