Acoustic Neuroma Resection Research Articles

Application and development of super minimally invasive surgery concept in acoustic neuroma resection

With the development of medicine, surgery has also experienced the development and evolution from traditional surgery to minimally invasive surgery, and then to super minimally invasive surgery (SMIS). Meanwhile, reducing surgical trauma and preserving and reconstructing nerve function have gradually become new goals of modern vestibular schwannoma (VS) resection surgery. The surgery of VS can be divided into hearing-preserving surgery (retrosigmoid approach and middle fossa approach) and non-hearing-preserving surgery (traditional translabyrinthine approach), according to whether the patient has practical hearing before operation. Improving the hearing preservation rate of hearing-preserving surgery and reconstructing the hearing of patients with non-hearing-preserving surgery are major challenges and hotspots. The traditional translabyrinthine approach has the highest proportion in the Department of Otolaryngology-Head and Neck Surgery, with the advantages of high facial nerve preservation rate and few intracranial complications. However, due to the resection of the cochlear nerve and labyrinth, the cochlea develops fibrosis, and patients lose the opportunity to reconstruct hearing through cochlear implantation. The new modified translabyrinthine approach can preserve the cochlear nerve and effectively reduce cochlear fibrosis, providing an opportunity for cochlear implantation to reconstruct the hearing. This is another important breakthrough in vestibular schwannoma surgery.

Changes of video head impulse test before and after translabyrinthectomy in patients with acoustic neuroma.

Acoustic neuroma (AN) is a benign tumor that usually affects a patient's hearing and balance function. For the screening and diagnosis of AN, the traditional approach mainly relies on audiological examination and magnetic resonance imaging (MRI), often ignoring the importance of vestibular function assessment in the affected area. As an emerging method of vestibular function detection, video head impulse test (vHIT) has been widely used in clinic, but research on its use in AN diagnosis is relatively limited. This study aims to explore the value of vHIT in the diagnosis of AN, vestibular dysfunction assessment, and postoperative compensation establishment in unilateral AN patients undergoing unilateral AN resection through labyrinthine approach. This retrospective study was conducted on 27 AN patients who underwent unilateral AN resection via labyrinthine approach from October 2020 to March 2022 in the Department of Otolaryngology-Head and Neck Surgery, the Second Xiangya Hospital, Central South University. vHIT was performed 1 week before surgery to assess vestibular function, pure tone audiometry (PTA) was used to assess hearing level, and ear MRI was used to assess tumor size. Follow-up vHIT was conducted at 1 week, 1 month, 6 months, and 1 year post-surgery. The correlation of vHIT with hearing and tumor size was analyzed. Preoperative vHIT showed that the posterior semicircular canal on the affected side was the most common semicircular canal with reduced vestibulo-ocular reflex (VOR) gain. There was a correlation between the VOR gain of vHIT on the affected side and the hearing level (r=-0.47, P<0.05) or tumor size (r=-0.54, P<0.01). The results of vHIT on the affected side showed that the hearing level and mean VOR gain of the anterior semicircular canal increased slightly with time, and the amplitude and saccade percentage of the dominant saccades of the 3 semicircular canals increased, while the latency time decreased, with the most obvious changes occurring 1 week post-surgery. vHIT can effectively monitor the changes of vestibular function in AN patients before and after surgery and has application value in assisting the diagnosis of vestibular dysfunction in AN patients.

New mania post acoustic neuroma resection: more than a coincidence

Mood disorder is a rare complication of acoustic neuroma resection, and therefore unlikely to be listed as a possible risk on a preoperative consent form. However, the occurrence of this has been recognised since as far back as 1914. This case study reports the new presentation of mania in a 65‐year‐old woman, seven weeks after surgical removal of an acoustic neuroma. The case study explores whether the acoustic neuroma and its surgical management could be directly causative of her psychiatric disorder, or whether it simply represents a psychological trigger in a susceptible patient.

Does labyrinthectomy have an impact on hearing in the contralateral ear during long-term follow-up?

ObjectiveTo quantify contralateral hearing outcomes after labyrinthectomy for unilateral Ménière's disease (MD). Study designRetrospective case series. SettingTertiary neurotology referral center. PatientsLabyrinth removal for the management of MD or translabyrinthine (TLAB) acoustic neuroma resection between 2008 and 2012. Main outcome measureLong-term hearing changes via pure tone averages (PTA). ResultsUpon comparison of low-frequency PTA (250, 500, 1000 Hz), MD patients experienced a greater degree of hearing loss during the follow-up period when compared to the TLAB lab group (7.54 ± 2.11 dB vs 2.39 ± 1.10 dB, p = 0.035). This difference as attributable to 12 (28.6 %) MD patients experiencing a ≥30 dB increase in low-frequency PTA, whereas none (0.0 %) of the TLAB surpassed this threshold. ConclusionsAt 10 years post-labyrinthectomy there is a heightened risk for MD patients to develop low-frequency sensorineural hearing loss. Clinicians should monitor for audiometric changes through regular testing in the decade following labyrinth removal.

Going the distance in acoustic neuroma resection: microsurgical outcomes at high-volume centers of excellence

High-volume hospitals are associated with improved surgical outcomes for acoustic neuromas (ANs). Due to the benign and slow-growing nature of ANs, many patients travel to geographically distant cities, states, or countries for their treatment. However, the impact of travel burden to high-volume centers, as well as its relative benefit are poorly understood. We compared post-operative outcomes between AN patients that underwent treatment at local, low-volume hospitals with those that traveled long distances to high-volume hospitals. The National Cancer Database was used to analyze AN patients that underwent surgery (2004-2015). Patients in the lowest quartile of travel distance and volume (Short-travel/Low-Volume: STLV) were compared to patients in the highest quartile of travel distance and volume (Long-travel/High-Volume: LTHV). Only STLV and LTHV cases were included for analysis. Of 13,370 cases, 2,408 met inclusion criteria. STLV patients (n = 1,305) traveled a median of 6 miles (Interquartile range [IQR] 3-9) to low-volume centers (median 2, IQR 1-3 annual cases) and LTHV patients (n = 1,103) traveled a median of 143 miles [IQR 103-230, maximum 4,797] to high-volume centers (median 34, IQR 28-42 annual cases). LTHV patients had lower Charlson/Deyo scores (p = 0.001), mostly received care at academic centers (81.7% vs. 39.4%, p < 0.001), and were less likely to be minorities (7.0% vs. 24.2%, p < 0.001) or underinsured (4.2% vs. 13.8%, p < 0.001). There was no difference in average tumor size. On multivariable analysis, LTHV predicted increased likelihood of gross total resection (odds ratio [OR] 5.6, 95% confidence interval [CI] 3.8-8.4, p < 0.001), longer duration between diagnosis and surgery (OR 1.3, 95% CI 1.0-1.6, p = 0.040), decreased length of hospital stay (OR 0.5, 95% CI 0.4-0.7, p < 0.001), and greater overall survival (Hazard Ratio [HR] 0.6, 95% CI 0.4-0.95, p = 0.029). There was no significant difference in 30-day readmission on adjusted analysis. Although traveling farther to high-volume centers was associated with greater time between diagnosis and treatment for AN patients, they experienced superior postoperative outcomes compared to patients who received treatment locally at low-volume centers. Enabling access and travel to high-volume centers may improve AN patient outcomes.

Clinical characteristics and risk factors for new-onset cervicogenic headache following elective craniotomy.

Clinical characteristics and risk factors for new-onset cervicogenic headache following elective craniotomy.

Is There a Plateau to the Learning Curve for Acoustic Neuroma Resection?-Experience and Outcomes from a Single Interdisciplinary Team Over Thirty Years.

Objective The evolution of acoustic neuroma (AN) care continues to shift focus on balancing optimized tumor resection and control with preservation of neurological function. Prior learning curve analyses of AN resection have demonstrated a plateau between 20 and 100 surgeries. In this study of 860 consecutive AN surgeries, we investigate the presence of an extended learning curve tail for AN resection. Methods A retrospective cohort study of AN resections by a single interdisciplinary team between 1988 and 2018 was performed. Proportional odds models and restricted cubic splines were used to determine the association between the timing of surgery and odds of improved postoperative outcomes. Results The likelihood of improved postoperative House-Brackmann (HB) scores increased in the first 400 procedures, with HB 1 at 36% in 1988 compared with 79% in 2004. While the probability of a better HB score increased over time, there was a temporary decrease in slope of the cubic spline between 2005 and 2009. The last 400 cases continued to see improvement in optimal HB outcomes: adjusted odds of HB 1 score were twofold higher in both 2005 to 2009 (adjusted odds ratio [aOR]: 2.11, 95% confidence interval [CI]: 1.38-3.22, p < 0.001) and 2010 to 2018 (aOR: 2.18, 95% CI: 1.49-3.19, p < 0.001). Conclusion In contrast to prior studies, our study demonstrates the steepest growth for learning, as measured by rates of preservation of facial function outcomes (HB 1), occurs in the first 400 AN resections. Additionally, improvements in patient outcomes continued even 30 years into practice, underlining the importance of lifelong learning.

Assessing Surgical Approaches for Acoustic Neuroma Resection: Do Patients Perceive a Difference in Quality-of-Life Outcomes?

The objective of this study is to further patient-physician discussion regarding postoperative quality of life expectations after surgical acoustic neuroma resection. This study is retrospective prospective. Qualifying patients were identified and administered Penn Acoustic Neuroma Quality-of-Life (PANQOL) Scale. The setting was Loyola University Chicago Health System. Three hundred twenty-six patients at our center with surgically resected acoustic neuroma between January 1990 and July 2021 completed the PANQOL. During postresection follow-up visits, patients were administered the PANQOL survey. The total PANQOL is comprised of questions addressing quality of life in seven domains of hearing, balance, face, energy, pain, health, and anxiety. Univariate and multivariable analyses were performed to test for associations between surgical approach and/or patient characteristics. Patients who were treated with retrosigmoid approach reported slightly higher PANQOL pain scores when compared with translabyrinthine approach. No association was found between responses on hearing PANQOL and surgical approach. No association was found between approach and total PANQOL score. However, on average female patients reported lower total PANQOL compared with male patients. The lack of association between patient response on hearing PANQOL and surgical approach illustrates the impact of preoperative patient counseling in appropriately setting patient expectations. The difference in pain PANQOL response may be due to a higher rate of occipital neuralgia due to incision placement and soft tissue retraction in the retrosigmoid patient group. Surgeons may consider alternative surgical incisions and soft tissue dissection to improve patient's quality of life with respect to postoperative pain.

Resection of small acoustic neuroma using the transcanal transvestibular endoscopic approach.

We evaluated the outcomes of resection of small acoustic neuromas using the transcanal transvestibular endoscopic approach. Two patients with a small acoustic neuroma were treated using this approach. The sizes of the tumors were 11 × 6 mm and 12 × 10 mm. Both tumors were removed completely without residual tumor tissue, and damage to the facial nerve and cochlear nerve was avoided. No patients developed postoperative vertigo, aggravation of postoperative facial paralysis, severe pain, or permanent postoperative complications. The patients were followed up for 6 months, and none developed recurrence. Resection of small acoustic neuromas by the transcanal transvestibular endoscopic approach is a simple and safe technique that achieves excellent functional results.

Automatic Segmentation of Intracochlear Anatomy in MR Images Using a Weighted Active Shape Model.

There is evidence that cochlear MR signal intensity may be useful in prognosticating the risk of hearing loss after middle cranial fossa (MCF) resection of acoustic neuroma (AN), but the manual segmentation of this structure is difficult and prone to error. This hampers both large-scale retrospective studies and routine clinical use of this information. To address this issue, we present a fully automatic method that permits the segmentation of the intra-cochlear anatomy in MR images, which uses a weighted active shape model we have developed and validated to segment the intra-cochlear anatomy in CT images. We take advantage of a dataset for which both CT and MR images are available to validate our method on 132 ears in 66 high-resolution T2-weighted MR images. Using the CT segmentation as ground truth, we achieve a mean Dice (DSC) value of 0.81 and 0.79 for the scala tympani (ST) and the scala vestibuli (SV), which are the two main intracochlear structures.Clinical Relevance- The proposed method is accurate and fully automated for MR image segmentation. It can be used to support large retrospective studies that explore relations between MR signal in preoperative images and outcomes. It can also facilitate the routine and clinical use of this information.

The Strategy of Facial Nerve Preservation in Acoustic Neuroma Surgery via Suboccipital Retrosigmoid Approach

Acoustic neuroma is a common intracranial tumor, with a prevalence of 80~90% in the lesions of cerebellopontine angle. Microsurgical removal remains its main therapy, and the retrosigmoid approach continues to be the most widely employed strategy for the surgical resection of acoustic neuromas, with preservation of facial nerve to be the important goal. In order to preserve the facial nerve, the facial nerve's function should be evaluated accurately before and after the operation. The course of the facial nerve and its variation in cerebellopontine cistern and internal auditory canal should be well understood. Adequate drilling of the posterior wall of the internal auditory canal is necessary. Sufficient decompression of intracranial pressure and the tumor is imperative. The principle of subperineural and bidirectionary dissection should be followed. The use of bipolar coagulation should decrease to the greatest extent, and facial nerve monitoring should be used throughout exposing and removal of the acoustic neuroma.

Middle cranial fossa approach for acoustic neuroma.

The middle fossa approach for the resection of small acoustic neuromas is a viable, but underutilized treatment modality with the goal of hearing preservation. The authors aim to demonstrate this approach and its nuances through this video presentation. A 38-year-old man presented with an incidentally discovered small, intracanalicular acoustic neuroma that was initially observed, but growth was noted. The patient had good hearing, and therefore a hearing preservation approach was offered. A gross-total resection was achieved, and the patient maintained good hearing postoperatively. This video demonstrates relevant anatomy, surgical indications, technical aspects of resection, including reconstruction, and postoperative outcomes.The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID21124

Cochlear T2 Signal May Predict Hearing Outcomes After Resection of Acoustic Neuroma.

Examine the impact of preoperative cochlear Fast Imaging Employing Steady-state Acquisition (FIESTA) and Constructive Interference in Steady State (CISS) signal intensity on hearing outcomes after middle cranial fossa (MCF) resection of acoustic neuroma (AN). Adult patients (≥18 years) who underwent MCF AN resection for hearing preservation (HP) between November 2017 and September 2019 were retrospectively reviewed. All patients had preoperative word recognition score (WRS) ≥50%. HP was defined as postoperative WRS ≥50%. A neuroradiologist blinded to patients' clinical and audiometric outcomes reviewed patients' preoperative magnetic resonance images. Ipsilateral-to-contralateral cochlear FIESTA/CISS signal intensity ratios were determined using hand-drawn regions of interest focused on the cochlear fluid. Preoperative and postoperative pure tone average (PTA) and WRS were reviewed. Fifty-one patients were reviewed (60.8% female). Mean age was 47 years and mean tumor size 9.2 mm (±3.8). Hearing was preserved in 56.9% (n = 29). FIESTA/CISS signal ratios did not significantly differ between patients with and without HP. Lower FIESTA/CISS signal ratios correlated with greater declines in hearing (r = 0.322, p = 0.011 for PTA; and r = 0.384, p = 0.004 for WRS). On multivariate analysis accounting for tumor size and preoperative PTA/WRS, decreases in FIESTA/CISS signal ratios independently predicted greater declines in hearing by PTA (b = -100.9, p = 0.012) and WRS (b = 76.208), although the latter result was not statistically significant (p = 0.078). Cochlear FIESTA/CISS signal intensity may be a predictor of postoperative hearing loss after MCF AN resection. In this cohort, degraded preoperative cochlear FIESTA/CISS signal strongly predicted postoperative hearing loss.Level of Evidence: IV.

Occipital Neuralgia following Acoustic Neuroma Resection.

Background While postoperative outcomes of acoustic neuroma (AN) resection commonly consider hearing preservation and facial function, headache is a critical quality of life factor. Postoperative headache is described in the literature; however, there is limited discussion specific to occipital neuralgia (ON) following AN resection. Objective The aim of this study is to investigate the effectiveness of conservative management and surgery. Methods We conducted a retrospective review of 872 AN patients who underwent resection at our institution between 1988 and 2017 and identified 15 patients (1.9%) that met International Classification of Headache Disorders criteria for ON. Results Of the 15 ON patients, surgical approaches included 13 (87%) retrosigmoid (RS), one (7%) translabyrinthine (TL), and one (7%) combined RS + TL. Mean clinical follow-up was 119 months (11-263). Six (40%) patients obtained pain relief through conservative management, while the remaining nine (60%) underwent surgery or ablative procedure. Three (38%) patients received an external neurolysis, four (50%) received a neurectomy, one (13%) had both procedures, and one (13%) received two C2 to 3 radio frequency ablations. Of the nine patients who underwent procedural ON treatment, seven (78%) patients achieved pain relief, one patient (11%) continued to have pain, and one patient (11%) was lost to follow-up. Of the six patients whose pain was controlled with conservative management and nerve blocks, five (83%) found relief by using neuropathic pain medication and one (17%) found relief on nonsteroidal anti-inflammatory drug. Conclusion Our series demonstrates success with conservative management in some, but overall a minority (40%) of patients, reserving decompression only for refractory cases.

Impact of Reconstruction With Hydroxyapatite Bone Cement on CSF Leak Rate in Retrosigmoid Approach to Vestibular Schwannoma Resection: A Review of 196 Cases.

To assess the impact of reconstructive technique on the incidence of cerebrospinal fluid (CSF) leak following retrosigmoid approach to acoustic neuroma resection. Retrospective case series. Academic medical center. A total of 1,200 patients with acoustic neuromas presented to our institution from 2005 to 2018. Of these, 196 patients underwent surgical resection via a retrosigmoid approach. At our institution, internal auditory canal (IAC) reconstruction following a retrosigmoid approach was performed with bone wax and muscle plug or Norian hydroxyapatite bone cement from 2005 to 2013. Starting in 2014, a newer model of bone cement, Cranios hydroxyapatite, was used exclusively for reconstruction. Rates of CSF leak were evaluated across different methods of IAC reconstruction and types of bone cement. Patients whose leaks were attributable to the craniectomy site were excluded from analysis. The postoperative CSF leak rate among patients who did not receive bone cement for IAC reconstruction was 15.6% (n.5). The leak rate amongst patients who received Norian bone cement was 6.3% (n.4). After introduction of Cranios bone cement, the total leak rate decreased to 1% (n.1). Compared with all other types of closure, Cranios had a significantly reduced rate of postoperative CSF leak (p < 0.005). The leak rate following Cranios versus Norian was also significantly reduced (p < 0.05). Leak rate was not affected by tumor size (p.0.30) or age (p.0.43). CSF leak rate following acoustic neuroma resection was significantly reduced by introduction of Cranios hydroxyapatite bone cement.

Bruns nystagmus occurring after resection of a giant cerebellopontine angle acoustic neuroma

Bruns Nystagmus is defined as a coarse, high-amplitude horizontal nystagmus with low oscillatory frequency as the patient looks towards the side of the lesion and a fine, low-amplitude, high- frequency primary-position nystagmus that increases as the patient looks opposite to the side of the lesion. It is usually associated with large tumors of the Cerebellopontine angle that causes significant brainstem distortion, compression of the flocculus and/or vestibulocerebellum. Here, we report a case of Bruns Nystagmus (BN) occurring as a new postoperative finding after resection of a giant cerebellopontine angle acoustic neuroma despite complete surgical resection, along with a review of the literature concerning the mechanisms of BN.

Sigmoid Sinus Patency following Vestibular Schwannoma Resection via Retrosigmoid versus Translabyrinthine Approach.

Introduction The treatment options for acoustic neuromas are observation with serial imaging, stereotactic radiation, or surgical resection. The most common surgical approaches are the translabyrinthine (TL), the retrosigmoid (RS), and the middle cranial fossa. During the TL approach the sigmoid sinus is decompressed with bipolar cautery to allow greater medial exposure. It is unknown if this causes any long-term narrowing or thrombus of the sigmoid sinus. Methods We performed a retrospective review of patients who underwent acoustic neuroma resection to determine if patients undergoing a TL approach for acoustic neuroma resection develop radiographic evidence of sigmoid sinus stenosis or thrombosis compared with patients undergoing a RS approach. Results A total of 128 patients were included in this study, 56 patients underwent a TL approach and 72 patients underwent a RS approach. We compared the preoperative and postoperative diameter of the ipsilateral and contralateral sigmoid sinus at proximal, midpoint, and distal locations on magnetic resonance imaging examinations. There was no significant difference between the preoperative and postoperative diameter of the ipsilateral or contralateral sigmoid sinus based on surgical approach. Conclusion Decompression of the sigmoid sinus during the TL approach does not have a significant postoperative effect on the dural venous sinus patency.

New-onset mania in an elderly patient five months after acoustic neuroma resection.

1. Even in cases of acoustic neuroma without psychiatric symptoms before surgical intervention, secondary mania could develop after surgery. 2. It is necessary to be aware of potential mania onset following acoustic neuroma resection for at least several months.

Simultaneous cochlear implantation and removal of acoustic neuroma: implications for hearing

To present our data evaluating the feasibility of simultaneous cochlear implantation with resection of acoustic neuroma. This paper describes a case series of eight adult patients with a radiologically suspected acoustic neuroma, treated at a tertiary referral centre in Newcastle, Australia, between 2012 and 2015. Patients underwent cochlear implantation concurrently with removal of an acoustic neuroma. The approach was translabyrinthine, with facial nerve monitoring and electrically evoked auditory brainstem response testing. Standard post-implant rehabilitation was employed, with three and six months' follow-up data collected. The main outcome measures were: hearing, subjective benefit of implant, operative complications and tumour recurrence. Eight patients underwent simultaneous cochlear implantation with resection of acoustic neuroma over a 3-year period, and had 25-63 months' follow up. There were no major complications. All patients except one gained usable hearing and were daily implant users. Simultaneous cochlear implantation with resection of acoustic neuroma has been shown to be a safe treatment option, which will be applicable in a wide range of clinical scenarios as the indications for cochlear implantation continue to expand.

Predictive Value of Preoperative and Intraoperative Neurophysiology in Evaluating Long-term Facial Function Outcome in Acoustic Neuroma Surgery.

To determine the role of neurophysiological preoperative and intraoperative parameters in providing prognostic information regarding facial nerve (FN) function at 1 year after translabyrinthine acoustic neuroma (AN) resection surgery. Prospective observational study in a tertiary referral center. Patients treated via translabyrinthine surgical approach for sporadic AN microresection between December 2015 and 2018. Patients underwent preoperative (electroneurography-ENG, electromyography-EMG, and Blink Reflex-BR) and intraoperative (FN motor action potential-MAP and continuous EMG traces) neurophysiological studies. FN function was graded postoperatively at 1 year using House-Brackmann Scoring System. Sixty-two patients were included in the analysis. Mean age was 53±10 years and average tumor diameter was 23 ± 9 mm. At 1 year a normal facial function was observed in 68% of patients. In the univariate analysis a pathologic BR, low FN MAP values and ratios, and the presence of pathological neurotonic tracing (A-trains) on continuous EMG were associated with a poor facial nerve function outcome at 1 year postoperatively. Pathological preoperative BR testing and intraoperative A-trains showed a statistical significance also in the multivariable analysis, regardless of tumor size. Preoperative pathological BR testing and A-train activity on intraoperative EMG are correlated with poor FN outcomes at 1 year postoperative. This may provide important prognostic information to both patients and treating neuro-otologists. In the future this may guide preoperative and postoperative patient counselling and possibly optimize timing of facial nerve reanimation in selected patients.