Anatomical Preservation Of Facial Nerve Research Articles

Surgical Outcome of Vestibular Schwannoma in a Tertiary Care Hospital, Dhaka

Background: Presenting symptoms, treatment considerations, and outcome are strongly related to the extension of vestibular schwannomas (VS). The aim of the current retrospective study was to analyze the clinical features, microsurgical treatment, and outcome of VS with brainstem compression. Methods: 130 patients presented with VS who had undergone operative procedures performed in our unit from Jan, 2017 to may, 2022. The facial nerve function and hearing assessment was done according to House-Brackmann [HB] grading and pure tone audiometry (PTA) respectively. All patients were operated by retro-sigmoid retromastoid sub-occipital approach. Results: Most patients had large tumors and had no useful hearing (75.38%), had disabling cerebellar ataxia (84.61%) and presented with features of raised intracranial pressure (46.15%). Complete tumor excision was carried out 92.30% and anatomical preservation of facial nerve was achieved in 87.50% cases. Hearing preservation was achieved in eight patients. Cerebrospinal fluid leak with or without meningitis and transient lower cranial nerve paresis were common complications. The mortality rate was 7.69% Conclusions: Complete tumor excision with good facial nerve preservation can be achieved in large vestibular schwannomas. Hearing preservation is difficult in larger tumors. Primary microsurgical resection is an appropriate management option for large VS. In our experience, this goal can be achieved safely and successfully by using the retromastoid retrosigmoid sub-occipital approach. Bang. J Neurosurgery 2023; 12(2): 86-93

Application of Subperineural Resection Technique in Vestibular Schwannomas: Surgical Efficacy and Outcomes in 124 patients.

ObjectiveWe aimed to explore the application and prospects of the subperineural resection technique for tumor separation and removal under the perineurium during surgery for vestibular schwannomas (VSs).MethodsThis study retrospectively analyzed 124 patients with VSs who underwent surgery via a retrosigmoid approach from July 2015 to October 2020 in the Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University. The data will be discussed with regard to the following aspects: clinical features, surgical strategies, tumor resection extent, facial–acoustic function preservation, and postoperative complications.ResultsGross total resection (GTR) of the tumor was achieved in 104 patients, with a GTR rate of 83.9%, and subtotal resection (STR) of the tumor was achieved in 20 patients. There was no significant difference in facial and acoustic nerve functional preservation between GTR and STR, as well as in tumor resection between solid and cystic tumors. The retention rate reached 97.6% in terms of complete anatomical facial nerve preservation. Facial nerve function was assessed using the House–Brackmann (HB) grading score. Consequently, HB grades of I–II, III–IV, and V–VI were determined for 96 (77.4%), 25 (20.2%), and 3 (2.4%) cases, respectively, 1 week postoperatively and accounted for 110 cases (88.7%), 13 cases (10.5%), and 1 case (0.8%), respectively, at 6 months. Fifteen of 35 (42.9%) patients with serviceable hearing before the operation still had serviceable hearing at 6 months postoperatively. There were 5 cases of cerebellar or brainstem bleeding after the operation, and one patient died. Multivariate logistic regression analysis showed that older age (≥60 years, p = 0.011), large tumor (>3 cm, p = 0.004), and cystic tumor (p = 0.046) were independent risk factors associated with the extent of adhesion between the tumor and the brainstem and facial–acoustic nerve.ConclusionWe successfully applied the subperineural resection technique to a large series of patients with VSs and achieved satisfactory results. Accurate identification of the perineurium and subperineural resection of the tumor can effectively reduce the disturbance of the facial–acoustic nerve during the operation and provide an intuitive basis for judging the tumor boundary. The subperineural resection technique may be conducive to improving the rate of total tumor resection and facial–acoustic nerve functional preservation in the surgical treatment of VSs.

Outcome of Surgery of Vestibular Schwannomas in a Tertiary Care Hospital in Bangladesh

Background: Presenting symptoms, treatment considerations, and outcome are strongly related to the extension of vestibular schwannomas (VS). The aim of the current retrospective study was to analyze the clinical features, microsurgical treatment, and outcome of VS with brainstem compression. Methods: Seventy patients presented with VS who had undergone operative procedures performed in our unit from 2017 to 2019. The facial nerve function and hearing assessment was done according to House-Brackmann [HB] grading and pure tone audiometry (PTA) respectively. All patients were operated by retro-mastoid suboccipital approach. Results: Most patients had large tumors and had no useful hearing (85%), had disabling cerebellar ataxia (92.86%) and presented with features of raised intracranial pressure (48.57%). Large sized tumors were in 32.86% and giant sized tumors were in 57.14% cases. Complete tumor excision was carried out 92.86% and anatomical preservation of facial nerve was achieved in 73.85% cases. Hearing preservation was achieved in 4 patients. Cerebrospinal fluid leak with or without meningitis and transient lower cranial nerve paresis were common complications. The mortality rate was 7.14%. Conclusions: Complete tumor excision with good facial nerve preservation can be achieved in large vestibular schwannomas. Hearing preservation is difficult in larger tumors. Primary microsurgical resection is an appropriate management option for large VS. In our experience, this goal can be achieved safely and successfully by using the retrosigmoid approach. Bang. J Neurosurgery 2021; 10(2): 175-181

Application of the grinding bone function of cut-ultrasound aspiration in internal auditory canal treatment of acoustic neuroma microsurgery

Objective To investigate the safety and reliability of using the grinding bone function of cut-ultrasound aspiration (CUSA) to conduct internal auditory canal treatment during acoustic neuroma microsurgery. Methods From January 2014 to June 2015, the clinical data of 33 patients with acoustic neuroma resected via suboccipital retrosigmoid approach at the Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology were analyzed retrospectively. The posterior superior walls of the internal auditory canals in 21 patients (CUSA group) were ground by using CUSA during the operation, 19 patients treated with the posterior superior walls of internal auditory canal using the grinding drill from May 2012 to October 2013 were selected as a control group (grinding drill group) in the operation at the same time. Electrophysiological monitoring, such as cranial nerve and brainstem auditory evoked potential were performed during the operation. House-Brackmann facial nerve function grading system was used to assess the facial nerve function for all patients within 1 week before and after procedure. Results The tumors of 20 cases (95%) in the CUSA group were totally removed. The facial nerves were preserved anatomically in 21 cases (100%), and the practical hearing was preserved in 5 cases (24%). House-Brackmann facial nerve function grade at day 7 after procedure: grade Ⅰ in 5 cases, grade Ⅱ in 8 cases, and grade Ⅲ-Ⅴ in 8 cases. The good reservation rate of facial nerve function was 62% (13/21). In the grinding drill group, the tumors of 17 cases were totally removed (90%), the rate of anatomical preservation of facial nerve was 95% (18/19). House-Brackmann facial nerve function grade: grade Ⅰ in 3 cases, grade Ⅱ in 6 cases, and grade Ⅲ-Ⅴ in 10 in cases, and the good reservation rate of facial nerve function was 47% (9/19). There was significant difference in the good reservation rate of facial nerve function between the 2 groups (P<0.05). Conclusions The application of CUSA is safe and effective in treatment of internal auditory canals with acoustic neuroma microsurgery. It is beneficial to the total resection of tumors and the protection of facial nerves. Key words: Neuroma, acoustic; Microsurgery; Cut-ultrasound aspiration; Internal auditory canal

Surgical Treatment of Vestibular Schwannoma. Review of 420 Cases

Introduction and objectivesVestibular schwannoma is the most frequent cerebellopontine angle tumour. The aim of our study is to reflect our experience in the surgical treatment of this tumour. Material and methodsRetrospective study of 420 vestibular schwannomas operated in our hospital between 1994 and 2014. We include tumour size, preoperative hearing, surgical approaches, definitive facial and hearing functional results, and complications due to surgery. ResultsA total of 417 patients with 420 tumours were analysed, 209 female (50.1%) and 208 male (49.9%). Mean age at diagnosis was 49.8±13.2 years. The majority of the tumours were resected through a translabyrinthine approach (80.2%). Total tumour removal was achieved in 411 tumours (98.3%), and anatomic preservation of facial nerve in 404 (96.2%). Definitive facial nerve outcome was House–Brackmann grade I and II in 69.9%, and was significantly better in tumours under 20mm. Surgical complications included cerebrospinal fluid leakage in 3 patients (0.7%) and retroauricular subcutaneous collection in 16 (3.8%), 5 cases of meningitis (1.2%), 4 patients with intracraneal bleeding (0.9%), and death in 3 patients (0.7%). ConclusionsSurgery is the treatment of choice for vestibular schwannoma in the majority of patients. In our experience, the complication rate is very low and tumour size is the main factor influencing postoperative facial nerve function.

Surgical Outcomes of Cerebellopontine Angle Tumors in 34 Cases

Introduction: Cerebellopontine angle tumors are a surgical challenge to many neurosurgeons who want to operate in this space. Although most of these tumors are benign, they are a challenge because of the complex anatomy and important neurovascular structures that traverse this space. Most common cerebellopontine angle tumor is vestibular schwannoma. The management of these cases is essentially surgical. There has been a change in the surgical strategy over the years from simple intratumoral decompression to complete microsurgical excision, to radical excision with facial nerve and hearing preservation.Objectives: To study the clinical and radiological characteristics, know the pathological types and determine the surgical resectability and outcome of cerebellopontine angle tumor.Materials and Methods: It is a retrospective study done in the department of Neurosurgery, Apollo Hospitals Dhaka. 34 patients diagnosed with cerebellopontine angle tumor were recruited into the study.Results: Among 34 cases of cerebellopontine angle tumors vestibular schwannoma alone constituted 79%. Most of the tumors were large or giant tumors. Total resection was done in 25% of vestibular schwannoma and 50% of meningiomas. Anatomical preservation of facial nerve was achieved in 73% of patients. Facial nerve function as measured by the House Brackmann system. Postoperatively 61% had a score of 1 or 2; 29% had a score of 3 or 4; and 8% had a score of 5 or 6. Other complications included 2 cases of CSF leak, 3 cases of meningitis, 2 cases of lower cranial nerve palsy and 1 patient died.Conclusion: Cerebellopontine angle tumors show high incidence from 3rd to 5th decade with common symptoms being hearing loss and ataxia. Most of the patients presented at a delayed stage with large to giant tumors with no useful hearing. Sub total excision with keeping anterior part of tumor for preserving facial nerve function is the goal.Pulse Vol.8 January-December 2015 p.8-14

Tratamiento quirúrgico del schwannoma vestibular. Revisión de 420 casos

Introduction and objectivesVestibular schwannoma is the most frequent cerebellopontine angle tumor. The aim of our study is to reflect our experience in the surgical treatment of this tumor Material and methodsRetrospective study of 420 vestibular schwannomas operated in our hospital between 1994-2014. We include tumor size, preoperative hearing, surgical approaches, definitive facial and hearing functional results, and complications due to surgery. ResultsA total of 417 patients with 420 tumors were analyzed, 209 female (50.1%) and 208 male (49.9%). Mean age at diagnosis was 49.8±13.2 years. The majority of the tumors were resected through a translabyrinthine approach (80.2%). Total tumor removal was achieved in 411 tumors (98.3%), and anatomic preservation of facial nerve in 404 (96.2%). Definitive facial nerve outcome was House-Brackmann grade I and II in 69.9%, and was significantly better in tumors under 20mm. Surgical complications included cerebrospinal fluid leakage in 3 patients (0.7%) and retroauricular subcutaneous collection in 16 (3.8%), 5 cases of meningitis (1.2%), 4 patients with intracraneal bleeding (0.9%), and death in 3 patients (0.7%). ConclusionsSurgery is the treatment of choice for vestibular schwannoma in the majority of patients. In our experience, the complication rate is very low and tumor size is the main factor influencing postoperative facial nerve function.

Management of Geniculate Ganglion Hemangiomas: Case Series and Systematic Review of the Literature.

To analyze facial nerve (FN) outcomes based on duration of FN palsy and surgical strategy in patients with geniculate ganglion hemangiomas (GGH). Case series and systematic review of the literature. Tertiary care center. All patients undergoing surgical resection of GGH from 1992 to 2014 were studied and a review of the English literature was performed. One hundred twenty unique patients (mean age 41.4 yrs, 44% female) were identified with GGH: 8 in the current series and 112 from the literature review. Of these patients, 94% presented with FN weakness, 18% reported hemifacial spasm, and 16% had hearing loss at presentation. Eleven patients underwent an initial period of observation, 6 of which experienced either growth or progression of FN dysfunction. One hundred fourteen subjects ultimately underwent surgical intervention. The average preoperative House-Brackmann (HB) score was 4.6 and the mean duration of preoperative FN palsy was 27 months (range, 1-132). The average postoperative HB score was 3.5 at the last follow-up. Anatomical FN preservation was reported in 44% of patients. Duration of FN palsy ≤12 months was associated with better pre- and postoperative FN outcome (HB 4.1 vs 5.1, p = 0.01 and 2.9 vs 4.0, p < 0.001, respectively). FN preservation was also associated with better postoperative FN outcome compared with interposition grafting (HB 2.6 vs 3.9, p < 0.001). GGHs are rare benign vascular malformations that present with progressive FN palsy. In most patients, early surgical intervention should be considered since shorter duration of FN paralysis and anatomical preservation of the FN are significant predictors of final FN outcome.

Application of modified enlarged translabyrinthine approach in the removal of vestibular schwannoma

To describe and analyze the surgical outcomes of modified enlarged translabyrinthine approach(ETLA), which is combined with middle ear eradication and blind sac technique. A retrospective study was conducted on 28 patients who underwent surgery for vestibular schwannoma (VS) via modified ETLA from Jan. 2001 to Dec. 2012. The sizes of tumors were 25-52 mm[(38.2 ± 9.1) mm (X(-) ± s)]. Main outcomes measures included the rate of total removal, the rate of cerebral spinal fluid (CSF) leakage after surgery, complications, and intraoperative anatomical preservation of facial nerve and facial nerve function. Among the 28 patients who underwent modified ETLA, the rate of total removal was 100%. There was no death after surgery via modified ETLA. The rate of CSF leakage after surgery was 3.5% (1/28). The rate of intraoperative anatomical preservation of facial nerve was 89.3% (25/28).Short-term and long-term good facial nerve function rates were 25.0% (7/28) and 42.9% (12/28), respectively. Modified ETLA is suitable for VS>3 cm with extension to the anterior region of cerebellopontine angle, VS involve with labyrinth part of facial nerve, high jugular bulb, proposing sigmoid sinus and highly pneumatized temporal bone. This approach can provide a wide surgical field and well prevention of CSF leakage.

Staged resection of large vestibular schwannomas

Staged resection of large vestibular schwannomas (VSs) has been proposed as a strategy to improve facial nerve outcomes and morbidity. The authors report their experience with 2-stage resections of large VSs and analyze the indications, facial nerve outcomes, surgical results, and complications. The authors compare these results with those of a similar cohort of patients who underwent a single-stage resection. A retrospective review of all patients (age > 18 years) who underwent surgery from 2002 to 2010 for large (≥ 3 cm) VSs at the authors' institution with a minimum of 6 months follow-up was undertaken. A first-stage retrosigmoid approach (without meatal drilling) was performed to remove the cerebellopontine angle portion of the tumor and to decompress the brainstem. A decision to stage the operation was made intraoperatively if there was cerebellar or brainstem edema, excessive tumor adherence to the facial nerve or brainstem, a poorly stimulating facial nerve, or a thinned or splayed facial nerve. A second-stage translabyrinthine approach was performed at a later date to remove the remaining tumor. The single-stage resection consisted of a retrosigmoid approach with meatal drilling. Patient charts were evaluated for tumor size, extent of resection, tumor recurrence, House-Brackmann facial nerve function grade, and complications. Twenty-eight and 19 patients underwent 2- or single-stage resection of a large VS, respectively. The average tumor size was 3.9 cm (range 3.2-7 cm) in the 2-stage group and 3.9 cm (range 3.1-5 cm) in the single-stage group. The mean follow-up was 36 ± 19 months in the 2-stage group versus 24 ± 14 months in the single-stage group. Gross-total or near-total resection was achieved in 27 (96.4%) of 28 patients in the 2-stage group and 15 (79%) of 19 patients in the single-stage group (p < 0.01). Anatomical facial nerve preservation was achieved in all but 1 patient (94.7%), and there were no recurrences on follow-up imaging in the 2-stage group. Good facial nerve functional outcome (House-Brackmann Grades I and II) at last follow-up was achieved in 23 (82%) of 28 patients in the 2-stage group and 10 (53%) of 19 patients in the single-stage group (p < 0.01). Cerebrospinal fluid leak-related complications (intracranial hypotension, blood patch, and lumboperitoneal shunt for pseudomeningocele) were more common in the 2-stage group. There were no postoperative strokes, hemorrhages, or deaths in either group. The authors' results suggest that staged resection of large VSs may potentially achieve better facial nerve outcomes. There does not appear to be added neurological morbidity with staged resections.

Surgical Results and Technical Refinements in Translabyrinthine Excision of Vestibular Schwannomas

Vestibular schwannomas (VSs) are the most common cerebellopontine angle tumors, accounting for 75% of all lesions in this location. To evaluate the results after removal of VS through the enlarged translabyrinthine approach, which is a widening of the classic translabyrinthine approach that gives larger access and provides more room to facilitate tumor removal and to minimize surgery-related morbidities. This was a retrospective study of 1865 patients who underwent VS excision through the enlarged translabyrinthine approach between 1987 and 2009. Mean age was 50.39 years. Mean tumor size was 1.8 cm. Median follow-up was 5.7 years. Total removal was achieved in 92.33% of cases; 143 patients had incomplete resection with evidence of regrowth in 8. In the 1742 previously untreated patients, anatomic preservation of facial nerve was achieved in 1661 cases (95.35%), and House-Brackmann grade I or II was reached in 1047 patients (59.87%). Facial nerve outcome was significantly better in tumors ≤ 20 mm. Surgical complications included cerebrospinal fluid leakage in 0.85%, meningitis in 0.10%, intracranial bleeding in 0.80%, non--VII/VIII cranial nerve palsy in 0.96%, cerebellar ataxia in 0.69%, and death in 0.10%. The technical modifications that evolved with increasing experience are described. The enlarged translabyrinthine approach is a safe and effective approach for the removal of VS. In our experience, the complication rate is very low and tumor size is still the main factor influencing postoperative facial nerve function with a cutoff point at around 20 mm.

The value of microsurgery for acoustic neuromas

Objective To evaluate the value of microsurgery for acoustic neuromas. Methods The author performed a retrospective study of 63 consecutive patients after vestibular schwannomas (VSs) microsurgery with the retrosigoid approaches. The tumor was debulked firstly and dissected from surrounding neural and vascular structures by gripping the tumor capsule, and then drilled of the IAC. Intraoperative electrophysiological monitoring of facial nerve function during operation.Results Total tumor resection was achieved in 52 cases, subtotal resection was achieved in 11 cases. The anatomic preservation of facial nerve was achieved in 58 cases, the acoustic nerve was preserved anatomically in 29 cases. Fifty-eight cases received a follow-up, the mean follow-up time was 7.2 years. Two recurrent patients were found and there were no operative deaths. A long term facial nerve status:twenty-three cases were in grade Ⅰ, twenty-nine cases in grade Ⅱ ,five cases in grade Ⅲ , one cases in grade Ⅳ. Hearing level had an improvement in 9 cases and remained unchanged in 8 cases. Conclusion Microsurgery treatment is the main choice of the treatment of VSs, could achieve better result in control of tumor and facial and acoustic nerve function restoration. Key words: Acoustic neuroma; Acoustic nerve; Facial nerve ; Microsurgery

Posterior petrous meningiomas: 82 cases

The aim of this study was to discuss posterior petrous meningiomas--their classification, clinical manifestations, surgical treatments, and patient outcomes. A retrospective analysis was performed in 82 patients with posterior petrous meningiomas for microsurgery. According to the anatomical relationship with the posterior surface of the petrous bone and with special reference to the internal auditory canal (IAC), posterior petrous meningiomas were classified into three types: Type I, located laterally to the IAC (28 cases); Type II, located medially to the IAC, which might extend to the cavernous sinus and clivus (32 cases); and Type III, extensively attached to the posterior surface of the petrous bone, which might envelop the seventh and eighth cranial nerves (22 cases). Sixty-eight (83%) of 82 cases involved total resection. The rate of anatomical preservation of facial nerve was 97.5%, whereas the functional preservation rate was 81%. The rate of hearing preservation was 67%. All Type I tumors were completely resected, and the rate of anatomical preservation of facial nerve was 100% and functional preservation was 93%. Regarding Type II lesions, 75% of 32 cases involved total resection; the rate of anatomical preservation of facial nerve was 97% and functional preservation was 75%. For Type III lesions, 73% of 22 cases were totally resected. The rate of anatomical preservation of facial nerve in patients with this tumor type was 95%, whereas functional preservation was 73%. Clinical manifestations and surgical prognoses are different among the various types of posterior petrous meningiomas. It is more difficult for Types II and III tumors to be resected radically than Type I lesions, and postoperative functional outcomes are significantly worse accordingly. The primary principles in dealing with this disease entity include preservation of vital vascular and central nervous system structures and total resection of the tumor as much as possible.

Surgery of vestibular schwannomas: An institutional experience

To report management results of vestibular schwannomas (VS) treated surgically in our institute, with particular reference to completeness of tumor excision, facial nerve and hearing preservation and complications of surgery. Retrospective study of 259 patients treated during the years 1988 to 2002. The facial nerve function and hearing assessment was done according to House-Brackmann [HB] grading and pure tone audiometry (PTA) respectively. All patients were operated by retro-mastoid sub-occipital approach. Most patients had large tumors and had no useful hearing (90%), had disabling cerebellar ataxia (88%) and presented with features of raised intra-cranial pressure (45%). Large sized tumors were in 41.3% and giant sized tumors were in 56% cases. Complete tumor excision was carried out in 96.5% and anatomical preservation of facial nerve was achieved in 79.2% cases. Hearing preservation was achieved in 8 patients. Cerebrospinal fluid leak with or without meningitis and transient lower cranial nerve paresis were common complications. The mortality was 6%. With experience, complete tumor excision with good facial nerve preservation can be achieved in large tumors. Hearing preservation is difficult in bigger tumors. Prevention and control of infection was a major concern.

Predictive Value of Postoperative Electrophysiologic Testing of the Facial Nerve After Cerebellopontine Angle Surgery

Our objective was to assess the ability of postoperative electroneuronography (ENoG) and electromyography (EMG) to predict clinical facial function 1 year postoperatively in patients with facial paralysis and an intact facial nerve after cerebellopontine angle surgery. The study was a prospective, nonrandomized, uncontrolled clinical trial on an outpatient basis, at a tertiary care hospital. Primary eligibility criteria include: (1) cerebellopontine angle (CPA) surgery with anatomical preservation of facial nerve, (2) complete facial nerve paralysis; and (3) 1 year follow-up. ENoG and EMG were measured at 1 and 3 months postoperatively, House-Brackmann facial nerve grade at 1 year postoperatively. The Kendall coefficient of rank correlation demonstrated that the 1 and 3 month postoperative ENoG data were significant predictors of ultimate facial nerve outcome. Tracking multiple ENoG examinations in a single patient, over time was of little predictive value. EMG was a poor predictor of facial nerve outcome. In general, patients with delayed facial nerve paralysis had better ultimate facial function than patients with immediate paralysis. Postoperative ENoG, but not EMG was a statistically significant predictor of ultimate facial nerve outcome after CPA surgery. Patients with delayed facial paralysis had better outcomes than those with immediate facial paralysis.

The impact of continuous electrophysiological monitoring on preservation of the facial nerve during acoustic tumour surgery

Continuous electromyographic (EMG) activity and responses to electrical stimulation of the facial nerve were monitored intraoperatively in 35 patients undergoing primary removal of acoustic neuroma. The rate of anatomical and immediate functional preservation of the facial nerve of these patients was compared with a matched population where a facial nerve stimulator and monitoring of facial muscle contraction by the anaesthetist only was employed. Overall, 94% (n = 33) of facial nerves were preserved anatomically in patients with continuous EMG monitoring, compared with 64% (n = 89) of patients (n = 139) without continuous monitoring. Amongst the 33 cases with anatomical facial nerve preservation, 64% (n = 21) had immediate functional preservation. Immediate functional preservation was only achieved in 39% (n = 35) of anatomically preserved facial nerves (n = 89) where conventional monitoring was used.