Surgical Resection Of Vestibular Schwannoma Research Articles

P.083 Use of jugular venous pressure to optimize outcomes of vestibular schwannoma resection: a review of the literature and proof of concept

Background: Surgical resection of vestibular schwannoma (VS) is often curative if gross total resection is achieved, however, it is a delicate procedure with high risk to the facial nerve. With retrosigmoid approach for resection, the head is positioned to maximize lateral head rotation and neck flexion in order to optimize the surgical field. However, this may inadvertently occlude cerebral venous drainage, elevating intracranial pressure (ICP) and increasing intraoperative bleeding. Methods: Here, we review relevant literature regarding the effects of head rotation and neck flexion on internal jugular vein (IJV) occlusion and ICP, and highlight the notion that head rotation and flexion may occlude the ipsilateral IJV, increasing ICP. Subsequently, we propose a novel technique using continuous, real-time monitoring of jugular bulb pressure (JBP) to detect obstructions in jugular venous flow and guide optimal head positioning prior to VS resection. Results: As proof of concept, we present a case in which JBP monitoring was employed to optimize head positioning prior to a VS resection, which shows a significant reduction in JBP compared to traditional positioning. Conclusions: This innovative approach offers promise in enhancing the safety and efficacy of intracranial surgery for VS and potentially other neurosurgical procedures.

Use of jugular venous pressure to optimize outcomes of vestibular schwannoma resection: a review of the literature and proof of concept

Background: Surgical resection of vestibular schwannoma (VS) and other benign posterior fossa tumors is often curative if gross total resection is achieved, however, these lesions pose unique challenges due to their intricate location and proximity to critical structures. Approaches for resection often utilize lateral head rotation and neck flexion in order to optimize the surgical field. However, this may inadvertently occlude cerebral venous drainage, elevating intracranial pressure (ICP) and increasing intraoperative bleeding, potentially increasing the operative risk to patients. Methods: We review relevant literature regarding the effects of head rotation and neck flexion on internal jugular vein (IJV) occlusion and ICP, and highlight the notion that head rotation and flexion may occlude the ipsilateral IJV, increasing ICP. Subsequently, we propose a novel technique using continuous, real-time monitoring of jugular bulb pressure (JBP) to detect obstructions in jugular venous flow and guide optimal head positioning prior to VS resection. Results: As proof of concept, we present a single-patient case in which JBP monitoring was employed to optimize head positioning prior to a VS resection, which shows a significant reduction in JBP compared to traditional positioning. Conclusion: This innovative approach offers promise in enhancing the safety and efficacy of intracranial surgery for VS and other neurosurgical procedures.

Socioeconomic Disparities in the Pursuit of Care at a High-Volume Institution for Surgical Resection of Vestibular Schwannomas.

Increased institutional surgical resection case volume for vestibular schwannomas (VSs) has been associated with improved patient outcomes, including reduced risk of prolonged hospital stay and readmission. Socioeconomic disparities in the pursuit of care at these high-volume institutions remain unknown. Retrospective cohort epidemiological study. National Cancer Database, a hospital-based registry of over 1,500 facilities in the United States. Adult VS patients (age, >18 years) treated surgically. High- versus low-volume facilities, defined using a facility case volume threshold of 25 cases per year. A risk-adjusted restricted cubic spline model was previously used to identify this risk threshold beyond which the incremental benefit of increasing case volume began to plateau. Sociodemographic factors, including race, ethnicity, income, insurance status, and rurality. Multivariable analyses were adjusted for patient and tumor characteristics, including age, sex, Charlson-Deyo score, and tumor size. A totoal of 10,048 patients were identified (median [interquartile range] age = 51 [41-60] years, 54% female, 87% Caucasian). Patients with Spanish/Hispanic ethnicity (OR = 0.71, 95% confidence interval [CI] = 0.52-0.96), income below median (OR = 0.63, 95% CI = 0.55-0.73]), and Medicare, Medicaid, or other government insurance versus private insurance (OR = 0.63, 95% CI = 0.53-0.74) had reduced odds of treatment at a high-volume facility. Further sensitivity analyses in which facility volume was operationalized continuously reinforced direction and significance of these associations. Socioeconomic disparities exist in the propensity for VS patients to be treated at a high-volume facility. Further work is needed to understand the nature of these associations and whether interventions can be designed to mitigate them.

Surgical outcomes in large vestibular schwannomas: should cerebellopontine edema be considered in the grading systems?

Large (> 3cm) vestibular schwannomas pose complexity in surgical management because of narrow working corridors and proximity to the cranial nerves, brainstem, and inner ear structures. With current vestibular schwannoma classifications limited in information regarding cerebellopontine edema, our retrospective series examined this radiographic feature relative to clinical outcomes and its possible role in preoperative scoring. Of 230 patients who underwent surgical resection of vestibular schwannoma (2014-2020), we identified 107 patients with Koos grades 3 or 4 tumors for radiographic assessment of edema in the middle cerebellar peduncle (MCP), brainstem, or both. Radiographic images were graded and patients grouped into Koos grades 3 or 4 or our proposed grade 5 with edema. Tumor volumes, radiographic features, clinical presentations, and clinical outcomes were evaluated. The 107 patients included 22 patients with grade 3 tumors, 39 with grade 4, and 46 with grade 5. No statistical differences were noted among groups for demographic data or complication rates. Unlike grades 3 and 4 patients, grade 5 patients presented with worse hearing (p < 0.001), larger tumors (p < 0.001), lower rates of gross total resection (GTR), longer hospital stays, and higher rates of balance dysfunction. With edema detected in 43% of this cohort, special considerations are warranted for grade 5 vestibular schwannomas given the preoperative findings of worse hearing, lower GTR rates, longer hospital stays, and 96% who pursued postoperative balance therapy. We propose that grade 5 with edema offers a more nuanced interpretation of a radiographic feature that holds relevance to treatment selection and patient outcomes.

Association Between Facility Surgical Volume and Excess Time in the Hospital After Surgical Resection of Vestibular Schwannomas

High surgical vestibular schwannoma case volume in a medical institution may decrease the risk of adverse outcomes among patients undergoing vestibular schwannoma surgery. To study the association between surgical vestibular schwannoma case volume and excess time in the hospital after vestibular schwannoma surgery. This cohort study evaluated data from the National Cancer Database from January 1, 2004, through December 31, 2019, on Commission on Cancer-accredited facilities in the US. The hospital-based sample comprised adult patients aged 18 years or older with a vestibular schwannoma treated with surgery. Facility case volume, defined as the mean number of surgical vestibular schwannoma cases per year in the 2 years preceding the index case. The primary outcome was a composite of prolonged hospital stay (>90th percentile) or 30-day readmission. Risk-adjusted restricted cubic splines were used to model the probability of the outcome according to facility volume. The inflection point (in cases per year) when the declining risk of excess time in the hospital began to plateau was selected as the threshold to define high- and low-volume facilities. Outcomes were compared among patients treated at high- and low-volume facilities, with mixed-effects logistic regression models adjusting for patient sociodemographic characteristics, comorbidities, tumor size, and clustering within facilities. Collected data were analyzed between June 24 and August 31, 2022. Among 11 524 eligible patients (mean [SD] age, 50.2 [12.8] years; 53.5% female; 46.5% male) who underwent surgical resection of vestibular schwannoma at 66 reporting facilities, the median length of stay was 4 (IQR, 3-5) days, and 655 patients (5.7%) were readmitted within 30 days. The median case volume was 16 (IQR, 9-26) cases per year. An adjusted restricted cubic spline model identified a downtrending probability of excess time in the hospital with increasing volume. The declining risk of excess time in the hospital began to plateau at a facility volume of 25 cases per year. Surgery at a facility with an annual case volume at or above this threshold was independently associated with a 42% reduction in the odds of excess time in the hospital compared with surgery at a low-volume center (odds ratio, 0.58; 95% CI, 0.44-0.77). This cohort study found that among adults undergoing vestibular schwannoma surgery, a higher facility case volume was associated with a reduced risk of prolonged hospital stay or 30-day readmission. A facility case volume of 25 cases per year may represent a risk-defining threshold.

Delayed Facial Nerve Paralysis After Vestibular Schwannoma Resection

To report the long-term outcome of delayed facial nerve paralysis (DFNP) after surgical resection ofvestibular schwannoma and evaluate the influence of various factors on the prognosis of facial nerve function. Of 265 patients who underwent surgical excision of VS through a retrosigmoid approach between April 2019 and October 2021, 15 (5.7%) developed DFNP and were retrospectively studied. Preoperative and postoperative data were collected and analyzed. The mean age of patients with DFNP was 42.6 years (range, 27-63 years), and 11 (73.3%) were male. Tumor size ranged from 12 to 37 mm (mean 24 mm) in largest dimension. All patients had normal (House-Brackmann [HB] I) facial nerve function preoperatively. Immediate postoperative facial nerve function was HB I in 12 patients (80%) and HB II in 3 patients (20%). The mean severity of DFNP onset was HB 4.7 (range, HB III-V). The average day of onset was postoperative day 12.6 (range, day 5-28). At 1-year follow-up, 12 patients (80%) were HB I, 1 patient (6.7%) was HB III, and 2 patients (13.3%) were HB IV. All patients who were HB III and IV at the last follow-up had immediate postoperative facial nerve function of HB II. Most patients who develop DFNP have a favorable prognosis. However, a small proportion of patients with deteriorated facial nerve function immediately after surgery have poor long-term outcomes, despite confirmation of their facial nerve integrity anatomically and by electrical stimulation.

Nomogram for Predicting Facial Nerve Outcomes After Surgical Resection of Vestibular Schwannoma.

ObjectiveThe facial nerve (FN) outcomes after vestibular schwannoma surgery seriously affect the social psychology and quality of life of patients. More and more attention has been paid to the protection of FN function. This study aimed to identify significant prognostic factors for FN outcomes after vestibular schwannoma surgery and create a new nomogram for predicting the rates of poor FN outcomes.MethodsData from patients who had undergone operations for vestibular schwannoma between 2015 and 2020 were retrieved retrospectively and patients were divided into good and poor FN outcomes groups according to postoperative nerve function. The nomogram for predicting the risk of poor FN outcomes was constructed from the results of the univariate logistic regression analysis and the multivariate logistic regression analysis of the influencing factors for FN outcomes after surgical resection of vestibular schwannoma.ResultsA total of 392 participants were enrolled. The univariate logistic regression analysis revealed that age, tumor size, cystic features of tumors, cerebrospinal fluid (CSF) cleft sign, tumor adhesion to the nerve, learning curve, and FN position were statistically significant. The multivariate logistic regression analysis showed that age, tumor size, cystic features of tumors, CSF cleft sign, tumor adhesion to the nerve, learning curve, and FN position were independent factors. The nomogram model was constructed according to these indicators. At the last follow-up examination, a good FN outcome was observed in 342 patients (87.2%) and only 50 patients (12.8%) was presented with poor FN function. Application of the nomogram in the validation cohort still gave good discrimination [area under the curve (AUC), 0.806 (95% CI, 0.752–0.861)] and good calibration.ConclusionThis study has presented a reliable and valuable nomogram that can accurately predict the occurrence of poor FN outcomes after surgery in patients. This tool is easy to use and could assist doctors in establishing clinical decision-making for individual patients.

Intraoperative Fluorescence With Second Window Indocyanine Green Enhances Visualization During Vestibular Schwannoma Surgery.

To investigate the utility of the so-called "second window" of indocyanine green (ICG) as a near-infrared fluorescent dye for intraoperative visualization. Three patients who underwent surgical resection of vestibular schwannoma (two retrosigmoid and one middle fossa approach). Patients underwent intravenous infusion of ICG at a mean dose of 4.8 mg/kg at a mean of 15.3 hours before surgical incision. Once tumor dissection began, near-infrared fluorescence was used alongside conventional operative microscopy to visualize tumor tissue. Ability to distinguish tumor tissue from adjacent nerves. Intraoperative fluorescence allowed for enhanced visualization of the tumor-nerve plane in all patients. However, the effect varied among patients, and the effect faded with increasing surgical time. ICG, a well-tolerated cyanine dye, demonstrates late fluorescence hours after administration secondary to diffusion into tumor as well as normal tissues (the so-called "second window" of fluorescence). Its fluorescence in the near-infrared spectrum is a promising adjunct for enhancing visualization of tumor planes during vestibular schwannoma surgery.

Opioid Prescribing Patterns After Skull Base Surgery for Vestibular Schwannoma.

Excessive opioid prescription is a source of prescription diversion and could contribute to chronic opioid abuse. This study describes the opioid prescribing patterns and risk factors for additional opioid prescription after surgical resection of vestibular schwannoma (VS). Retrospective chart review. Single tertiary referral center. Adult VS patients undergoing surgical resection between May 2019 and March 2020. Opioid use postoperatively and up to 60 days following surgery were characterized from medical records and by querying the state-wide Controlled Substance Utilization Review and Evaluation System. The presence of additional opioid prescriptions within 60 days of surgery. A total of 109 patients (mean age 50 yrs, 65.5% female) were prescribed an average of 138.2 ± 117.8 mg of morphine equivalents (MME). Twenty-two (20.9%) required additional prescriptions of 163.2 ± 103.2 MME. Age, gender, tumor size, or surgical approach (translabyrinthine, retrosigmoid, versus middle fossa) were not associated with additional prescriptions. Patients with additional prescriptions had higher body mass index (BMI 28.8 vs. 25.8 kg/m2, p = 0.015) and required more opioid medications during hospitalization (51.8 vs. 29.1 MME, p = 0.002). On multivariate logistic regression, higher BMI (odds ratio [OR] 1.32; p = 0.001), history of headaches (OR 11.9, p = 0.011), and history of opioid use (OR 29.3, p = 0.008) were associated with additional prescription. Additional opioid prescriptions may be necessary in a portion of VS patients undergoing surgery. The choice of surgical approach is not associated with excess opioid requirements. Patients with higher BMI, history of headaches, or preoperative opioid use may require additional prescriptions.

Application of Mixed Reality Technology in Surgical Resection of Vestibular Schwannoma and Doctor-patient Communication

Application of Mixed Reality Technology in Surgical Resection of Vestibular Schwannoma and Doctor-patient Communication

Preoperative Sudden Hearing Loss May Predict Hearing Preservation After Retrosigmoid Resection of Vestibular Schwannoma.

Describe the effect of preoperative sudden hearing loss (SHL) on likelihood of hearing preservation (HP) after surgical resection of vestibular schwannoma (VS). Retrospective chart review. Tertiary referral center. Adult patients (≥18 years) who underwent retrosigmoid VS resection for HP between February 2008 and December 2018 were reviewed. All patients had preoperative word recognition score (WRS) of at least 50%. Similarly, HP was defined as postoperative WRS of more than or equal to 50%. Regression analysis was used to describe the effect of SHL on HP, accounting for tumor size, and preoperative hearing quality. All patients underwent retrosigmoid VS resection for HP. WRS of at least 50%. Of 160 patients who underwent retrosigmoid VS resection during the study period, 153 met inclusion criteria. Mean tumor size was 14.0 (±6) mm. Hearing was preserved in 41.8% (n = 64). Forty patients (26.1%) had a history of preoperative SHL. Among 138 patients (90.2%) in whom the cochlear nerve was anatomically preserved during surgery, HP was achieved in 61.8% of those with SHL (21 of 34) and 41.3% of those without SHL (43 of 104) (p = 0.0480). On univariate and multivariate analysis (accounting for tumor size and preoperative hearing quality), SHL was a significant positive predictor of HP (odds ratio 2.292, p = 0.0407 and odds ratio 2.778, p = 0.0032, respectively). In patients with VS and retained serviceable hearing, SHL is an independent predictor of HP after retrosigmoid microsurgical resection when the cochlear nerve is preserved.

Clinical Predictors of Facial Nerve Outcomes After Surgical Resection of Vestibular Schwannoma.

To identify clinical predictors of facial nerve (FN) outcomes after microsurgical resection of vestibular schwannoma (VS). Prospective cohort study. Academic medical center. Consecutive patients undergoing VS resection from November 2017 to October 2019 were included. FN function was evaluated with the House-Brackmann (HB) scale and stratified into good (HB I-II) and poor (HB III-VI) function. Analyses included descriptive statistics, correlation, and logistic regression. Of 256 patients who met criteria (mean age, 47.7 years; 62.5% female), 227 (88.7%) achieved good FN function postoperatively and 238 (93.0%) at latest follow-up (mean, 154.8 days). Operative approaches consisted of translabyrinthine (50.8%), retrosigmoid (25.0%), and middle fossa craniotomies (24.2%). Extent of resection was decided intraoperatively, and gross or near total resection was accomplished in 237 (92.6%) cases. Postoperative HB grade correlated with latest HB grade (0.615, P < .001). Factors associated with good postoperative FN function included small tumor size (≤15 mm; odds ratio [OR], 2.425; P = .042), gross or near total resection (OR, 3.170; P = .041), and ≥100-µV intraoperative FN electromyographic response to a 0.05-mA stimulus (OR, 22.242; P < .001). Factors associated with good FN function at latest follow-up included gross total resection (OR, 7.764; P = .003) and ≥100-µV FN electromyographic response (OR, 8.518; P < .001), accounting for surgical approach and tumor size. Microsurgical resection of VS can be accomplished with excellent FN outcomes. Gross total resection and ≥100-µV intraoperative FN electromyographic response predicted excellent FN outcomes. Immediate postoperative FN function is a prognosticator of long-term FN function.

National Trends in Surgical Resection of Vestibular Schwannomas.

To characterize the national trend for surgical resection of vestibular schwannoma (VS) and to assess changes in demographics, length of stay (LOS), discharge patterns, and hospital charges. Population-based inpatient registry analysis. National Inpatient Sample and SEER database (Surveillance, Epidemiology, and End Results). Retrospective review of the US National Inpatient Sample and the SEER database from 2001 to 2014 of all patients who underwent resection of VS. A total of 24,380 VS resections were performed. While the annual incidence of VS remained stable at 1.38 per 100,000, surgical volume declined by 36.1%, from 2807 in 2001 to 1795 in 2014 (R2 = 0.58). Total hospital charges more than doubled, from $52,475 in 2001 to $115,164 in 2014 ($4478 per year, R2 = 0.96). While most procedures were performed at large-sized hospitals, this decreased from 89% in 2002 to 75.8% in 2014. Average LOS remained stable at 5.2 days during the study period. The number of discharges to a nursing facility increased from 113 (5.5%) in 2002 to 245 (13.6%) in 2014 (P = .0002). VS resection has evolved in the United States. While the incidence remained stable, surgical volume decreased by 36%, and hospital charges more than doubled. More cases are being performed at smaller hospitals. Although LOS did not vary significantly, there is an increase in nonroutine discharges. These data may guide future research in resource utilization in neurotology.

Clinical outcomes of resecting scarpa's ganglion during vestibular schwannoma surgery

Vestibular schwannomas are slow-growing tumors arising from the Schwann cells of the vestibular nerve. Scarpa’s ganglion, the vestibular nerve ganglion, is located within the internal auditory meatus. Surgical treatment of vestibular schwannomas carries the potential of resecting Scarpa’s ganglion along with the tumor. No prior studies have evaluated outcomes based on the presence of Scarpa’s ganglion within tumor specimens. The neurosurgery patient records were queried for patients who underwent surgical resection of vestibular schwannomas at the University of Missouri Healthcare between January 1, 2008 and December 31, 2018. Inclusion criteria consisted of minimum age of 18, imaging demonstrating an eighth nerve tumor, surgical resection thereof, and a final pathological diagnosis of WHO grade I schwannoma. Data were collected retrospectively. The histological slides of the tumors were reviewed, and the presence or absence of the ganglion was noted. Outcomes analyzed included postoperative dizziness, hearing, and facial nerve function. Fifty-two patients met inclusion criteria. Ten (19%) resected tumors contained portions of the ganglion. No difference in risk of resection of ganglion occurred based on the surgical approach (p = 0.2454). Mean follow-up duration was 24.6 months ± 26.2 standard deviation. No differences in postoperative hearing or dizziness (p = 0.8483 and p = 0.3190 respectively) were present if Scarpa’s ganglion was resected. House-Brackmann classification of facial nerve function at last follow-up was similar (p = 0.9190). Resection of Scarpa’s ganglion with vestibular schwannomas does not increase risk of post-operative dizziness, facial nerve weakness, or hearing loss.

Associations of Vestibular Tests With Penn Acoustic Neuroma Quality of Life Scores After Resection of Vestibular Schwannoma.

Determine associations between preoperative caloric testing and video head impulse testing (vHIT) with baseline and postoperative Penn Acoustic Neuroma Quality of Life (PANQOL) scores following resection of vestibular schwannoma (VS). Retrospective case series. Two tertiary referral hospitals. Adult patients with unilateral VS, preoperative calorics, vHIT, and dizziness handicap inventory (DHI) score. Surgical resection of VS and postoperative surveys. PANQOL scores. Forty-three patients were included (58.1% women) with a median age of 54 years (range, 28-82). Mean tumor size was 14.8 mm (σ=8.6), and 28 (65.1%) were right-sided. Average preoperative vHIT gain was 0.7 (σ = 0.3). Covert and overt saccades were present in 8 (25%) and 14 (42.4%) patients, respectively. Average preoperative unilateral weakness was 47% (σ = 33.2). Translabyrinthine approach was performed in 26 (60.5%) patients. No significant difference of PANQOL scores was noted at baseline or over time between patients with normal (>0.8) or abnormal (<0.8) gain. Patients with more unilateral weakness (>50%) had significantly higher baseline PANQOL scores compared with those with < 25% or 25 to 50% (p = 0.02), but had significant improvement in scores over time (p = 0.01). Higher preoperative DHI preoperatively was significantly associated with worse PANQOL scores at all timepoints (β=0.57, p = 0.0064). No differences in PANQOL scores amongst surgical approaches were observed. Preoperative vestibular testing with vHIT, calorics, DHI, and baseline PANQOL surveys may allow for patient counseling regarding postoperative quality of life over time.

Role of Endoscopy in Resection of Intracanalicular Vestibular Schwannoma via Middle Fossa Approach: Technical Nuances

Surgical resection of vestibular schwannomas (VS) located within the internal auditory canal (IAC) is challenging, especially those located very laterally in the IAC. Various transcranial approaches have been described for resection of intracanalicular VS including retrosigmoid, translabyrinthine, and middle fossa approaches. Each approach has its indications, advantages, and limitations. The middle fossa approach (MFA) is considered by many authors as the gold standard approach for resection of small intracanalicular VS in young patients with serviceable hearing; however, there is often a limitation in complete visualization of the tumor. The authors present an illustrative case to highlight the technical nuances of complementary use of endoscopy in MFA for complete resection of intracanalicular VS located at the IAC fundus, preserving preoperative hearing status and mainting intact facial nerve function. In our experience, the combined use of the endoscope and the microspe as described here and illustrated in our case, improves visualization of the IAC and its contents, improving ressection and outcomes. MFA allows for a direct yet safe surgical corridor to small intracanalicular VS. The implementation of endoscopy with MFA, especially for VS located laterally in the IAC, allows for better opportunity for complete resection of the tumor with improved preservation of hearing and facial nerve function.

Delayed Facial Nerve Paralysis after Vestibular Schwannoma Resection

Objective To describe the incidence and clinical course of patients who develop delayed facial nerve paralysis (DFNP) after surgical resection of vestibular schwannoma. Setting Tertiary skull base center. Methods Retrospective chart review. Results Two hundred and forty six consecutive patients, who underwent surgical resection for vestibular schwannoma at a single center between 2010 and 2015, were analyzed. Of these patients, 22 (8.9%) developed DFNP, defined here as deterioration of function by at least 2 House-Brackmann (HB) grades within 30 days in patients with immediate postoperative HB ≤ 3. The mean age of DFNP patients was 47.2 years (range: 17-67) and 16 (73%) were female. The mean tumor size in greatest dimension was 2.1 cm (range: 0.7-3.5 cm). At the conclusion of each case, the facial nerve stimulated at the brainstem. Mean immediate postoperative facial nerve function was HB 1.8 (range: 1-3). Average facial nerve function at the 3-week-postoperative visit was 4.4 (range: 2-6). In 1-year, 8 patients (36%) recovered HB 1 function, 10 patients (46%) recovered to HB 2, and 2 patients (9%) were HB 3. The remaining 2 patients did not recover function and were HB 6 at last follow-up. Initial postoperative facial nerve function (HB 1 or HB 2) was associated with improved recovery to normal (HB 1) function ( p = 0.018). Conclusion A majority of patients that develop delayed paralysis will recover excellent facial nerve function. Patients should be counseled; however, a small percentage of patients will not recover function long-term, despite having a previously functioning and anatomically intact nerve.

Risk Factors for Readmission with Cerebrospinal Fluid Leakage Within 30 Days of Vestibular Schwannoma Surgery.

Cerebrospinal fluid (CSF) leak is a well-recognized complication after surgical resection of vestibular schwannomas and is associated with a number of secondary complications, including readmission and meningitis. To identify risk factors for and timing of 30-d readmission with CSF leak. Patients who had undergone surgical resection of a vestibular schwannoma from 1995 to 2010 were identified in the California Office of Statewide Health Planning and Development database. The most common admission diagnoses were identified by International Classification of Disease, ninth Revision, diagnosis codes, and predictors of readmission with CSF leak were determined using logistic regression. A total of 6820 patients were identified. CSF leak, though a relatively uncommon cause of admission after discharge (3.52% of all patients), was implicated in nearly half of 490 readmissions (48.98%). Significant independent predictors of readmission with CSF leak were male sex (odds ratio [OR] 1.72, 95% confidence interval [CI] 1.32-2.25), first admission at a teaching hospital (OR 3.32, 95% CI 1.06-10.39), CSF leak during first admission (OR 1.84, 95% CI 1.33-2.55), obesity during first admission (OR 2.10, 95% CI 1.20-3.66), and case volume of first admission hospital (OR of log case volume 0.82, 95% CI 0.70-0.95). Median time to readmission was 6 d from hospital discharge. This study has quantified CSF leak as an important contributor to nearly half of all readmissions following vestibular schwannoma surgery. We propose that surgeons should focus on technical factors that may reduce CSF leakage and take advantage of potential screening strategies for the detection of CSF leakage prior to first admission discharge.

Internal Auditory Canal Reconstruction After Vestibular Schwannomas Removal Through Retrosigmoid-Transmeatal Approach

Objectives: To present a technique of internal auditory canal (IAC) reconstruction using a pediculated dural flap, after removal of vestibular schwannomas through the retrosigmoid craniotomy. Methods: From a series of 213 patients with vestibular schwannomas operated between January 2008 and March 2016 through the retrosigmoid-transmeatal approach, 183 underwent reconstruction of the internal auditory canal with a pediculated dural flap. The IAC was drilled towards the fundus preserving the labyrinthine structures. The dura mater over the IAC was dissected from the bone, remaining pediculated at the entrance of the jugular foramen. This dural flap was used to cover the cranial nerves inside the IAC after tumor removal. Opened mastoid cells and the IAC were closed with muscle or fat grafts and fibrin glue. Results: Reconstruction of the IAC using the described technique was possible in in 183 cases. Fifteen patients (6.8%) developed postoperative cerebrospinal fluid (CSF) leakage and seven patients required reoperation (3.2%) to close the fistulae. Postoperative magnetic resonance imaging (MRI) examinations showed the presence of CSF within the IAC around the preserved cranial nerves. Conclusions: This technique of IAC reconstruction after surgical resection of vestibular schwannomas may avoid scar and adhesion of muscle or fat tissue with preserved cranial nerves, allowing CSF enter inside the IAC. It may help to identify tumor remnants and/or recurrences in postoperative MRI examinations. Comparative studies are needed to evaluate if this technique improves postoperative hearing and facial nerve outcomes.

Артериовенозная фистула после удаления вестибулярной шванномы

Артериовенозная фистула после удаления вестибулярной шванномы