[Effect analysis of facial nerve decompression surgery in the treatment of Bell's palsy and Hunt syndrome].

Objective:To summarize and analyze the effect of facial nerve decompression surgery for the treatment of Bell's palsy and Hunt syndrome. Methods:The clinical data of 65 patients with facial nerve palsy who underwent facial nerve decompression in our center from October 2015 to October 2022 were retrospectively analyzed, including 54 patients with Bell's palsy and 11 patients with Hunter syndrome. The degree of facial paralysis（HB grade） was evaluated before surgery, and ENoG, pure tone audiometry, temporal bone CT and other examinations were completed. All patients had facial palsy with HB grade V or above after conservative treatment for at least 1 month, and ENoG decreased by more than 90%. All patients underwent facial nerve decompression surgery through the transmastoid approach within 3 months after onset of symptoms. The recovery effect of facial nerve function after surgery in patients with Bell's palsy and Hunter syndrome was summarized and analyzed. In addition, 15 cases in group A（operated within 30-60 days after onset） and 50 cases in group B（operated within 61-90 days after onset） were grouped according to the course of the disease（the interval between onset of symptoms and surgery） to explore the effect of surgical timing on postoperative effect. Results:There was no significant difference between the two groups of patients with Chi-square test（P=0.54） in 42 patients（77.8%, 42/54） with Bell's palsy and 7 patients（63.6%, 7/11） in patients with Hunter syndrome who recovered to grade Ⅰ-Ⅱ. According to the course of the disease, 10 cases（66.7%, 10/15） in group A recovered to grade Ⅰ-Ⅱ after surgery. In group B, 39 patients（78.0%, 39/50） recovered to grade Ⅰ-Ⅱ after surgery, and there was no statistically significant difference between the two groups by Chi-square test（P=0.58）. Conclusion:Patients with Bell's palsy and Hunter syndrome can achieve good results after facial nerve decompression within 3 months of onset, and there is no significant difference in the surgical effect between the two types of patients.

Bilateral Nervus Intermedius Sectioning for Geniculate Neuralgia: Case Report and Operative Video.

BACKGROUND AND IMPORTANCE: Geniculate neuralgia is a rare condition characterized by excruciating ear pain. Surgical options for geniculate neuralgia include microvascular decompression and sectioning of the nervus intermedius. We report herein a case of bilateral geniculate neuralgia treated by nervus intermedius sectioning without prior microvascular decompression. To our knowledge, this is the first report of this treatment strategy with a subsequent description of the side effects of bilateral nervus intermedius disruption. CLINICAL PRESENTATION: A 54-yr-old woman presented with bilateral geniculate neuralgia, worse on the left, refractory to medical therapy. Surgical treatment options were reviewed, including microvascular decompression and sectioning of the nervus intermedius. She opted for left nervus intermedius sectioning. The procedure was uncomplicated and no compressive vascular loop was identified during surgery. Postoperatively, she had complete symptom resolution with no discernable side effects. Three years later, the patient developed worsening geniculate neuralgia on the contralateral side. After the discussion of treatment options, she opted again for sectioning of the contralateral nervus intermedius with successful resolution of all symptoms after surgery. Following surgery, the patient identified partial impairment of lacrimation and gustation. She continued to have functional taste of the anterior two-thirds of the tongue, lacrimation, and hearing bilaterally. CONCLUSION: Bilateral sectioning of nervus intermedius may provide benefit in patients with bilateral geniculate neuralgia without egregious side effects. However, lacrimatory and gustatory alterations are a potentially significant side effect with a wide range of symptomatology.

A Case Report of Pediatric Geniculate Neuralgia Treated with Sectioning of the Nervus Intermedius and Microvascular Decompression of Cranial Nerves IX and X.

BACKGROUND: Classic geniculate neuralgia (GN) is a rare condition characterized by lancinating pain centered in the ear and not involving the throat. To the best of our knowledge, no case of pediatric GN has been reported in the English literature. CASE PRESENTATION: We present the first reported case of successfully treated GN in a child via an endoscopic approach. The patient was a 9-year-old boy who presented with a 1-year history of lancinating right ear pain. Neuroleptics resulted in a short-lived improvement in symptoms, but with significant side effects. Extensive evaluation by multiple specialties did not reveal a cause for his pain. Imaging disclosed a tortuous loop of the right posterior inferior cerebellar artery abutting cranial nerves IX and X but no other abnormalities. The patient underwent an endoscopic microvascular decompression of cranial nerves IX and X, and sectioning of the nervus intermedius through a right retromastoid craniotomy. Postoperatively, the patient reported complete resolution of his symptoms that persisted at 3 months of follow-up. At the 5-year follow-up, the patient maintained pain relief and was developing normally. CONCLUSION: GN can affect the pediatric population. In carefully selected patients with consistent clinical and radiographic presentation, sectioning of the nervus intermedius and microvascular decompression of the lower cranial nerves can be an effective treatment.

Contrast-enhanced magnetic resonance imaging of facial nerve swelling in patients with severe Ramsay Hunt syndrome.

OBJECTIVE: In Ramsay Hunt syndrome, contrast enhancement of magnetic resonance (MR) imaging seen in the affected facial nerve in the majority of cases, but its clinical significance has not been well investigated to date. The aim of this study was to elucidate the clinical significance of this imaging sign by quantitively investigating the correlation between the signal increase and swelling of the facial nerve. We also investigated the temporal change in this sign and its correlation with recovery. METHODS: We retrospectively evaluated swelling of the facial nerve in 16 patients with severe Ramsay Hunt syndrome who underwent both contrast-enhanced magnetic resonance imaging and facial nerve decompression surgery via a transmastoid approach alone or in combination with a middle cranial approach. All the patients had a Yanagihara score of ≤8 points and facial nerve degeneration of ≥90% confirmed by either a nerve excitability test or electroneurography. Swelling of the facial nerve was evaluated intraoperatively using a 4-point grading system. RESULTS: A significant correlation was observed between contrast enhancement on T1-weighted images and facial nerve swelling in the labyrinthine segment, geniculate ganglion, and pyramidal segment (P = 0.030, P = 0.018, and P = 0.037, respectively). Furthermore, the contrast enhancement increased significantly as more time elapsed after the onset of facial palsy (mean ± standard error, 14.7 ± 2.3 days, range, 5-42 days) in the geniculate ganglion and pyramidal segment (correlation coefficient, 0.546 and 0.689, P = 0.022 and P = 0.002, respectively). Patients with good recovery (Yanagihara score of ≥36) showed significantly lower contrast enhancement in the tympanic and mastoid segments (P = 0.021 and 0.020, respectively) than those who with poor recovery. CONCLUSION: In particular segments of the facial nerve, contrast enhancement on T1-weighted image correlated with facial nerve swelling and recovery. These observations underscore the clinical significance of contrast enhancement on T1-weighted images in patients with Ramsay Hunt syndrome.

Nervus intermedius and the surgical management of geniculate neuralgia.

OBJECTIVE: Geniculate neuralgia (GN) is an uncommon craniofacial pain syndrome attributable to nervus intermedius (NI) dysfunction. Diagnosis and treatment can be challenging, due to the complex nature of ear sensory innervation, resulting in clinical overlap with trigeminal neuralgia (TN) and glossopharyngeal neuralgia (GPN). METHODS: A retrospective review of a prospective neurosurgical database at our institution was performed, 2000-2017, with a corresponding systematic literature review. Pain outcomes were dichotomized as unfavorable for unchanged/worsened symptoms versus favorable if improved/resolved. Eight formalin-fixed brains were examined to describe NI at the brainstem. RESULTS: Eleven patients were surgically treated for GN-9 primary, 2 reoperations. The median age was 48, 7 patients were female, and the median follow-up was 11 months (range 3-143). Seven had ≥ 2 probable cranial neuralgias. NI was sectioned in 9 and treated via microvascular decompression (MVD) in 2. Five patients underwent simultaneous treatment for TN (4 MVD; 1 rhizotomy) and 5 for GPN (3 MVD; 2 rhizotomy). Eleven reported symptomatic improvement (100%); 8 initially reported complete resolution (73%). Pain outcomes at last contact were favorable in 8 (73%)-all among the 9 primary operations (89% vs 0%, p = 0.054). Six prior series reported outcomes in 111 patients. CONCLUSIONS: GN is rare, and diagnosis is confounded by symptomatic overlap with TN/GPN. Directed treatment of all possible neuralgias improved pain control in almost all primary operations. Repeat surgery seems a risk factor for an unfavorable outcome. NI is adherent to superomedial VIII at the brainstem; the intermediate/cisternal portion is optimal for visualization and sectioning.

Effects of a sensory branch to the posterior external ear canal: coughing, pain, Ramsay Hunt's syndrome and Hitselberger's sign.

BACKGROUND: A distinct nerve innervating the external auditory canal can often be identified in close relation to the facial nerve when gradually thinning the posterior canal wall. This nerve has been attributed to coughing during cerumen removal, neuralgic pain, Hitselberger's sign and vesicular eruptions described in Ramsay Hunt's syndrome. This study aimed to demonstrate the origin and clinical impact of this nerve. METHODS AND RESULTS: In patients with intractable otalgia or severe coughing whilst inserting a hearing aid, who responded temporarily to local anaesthesia, the symptoms could be resolved by sectioning a sensory branch to the posterior canal. In a temporal bone specimen, it was revealed that this nerve is predominantly a continuation of Arnold's nerve, also receiving fibres from the glossopharyngeal nerve and facial nerve. Histologically, the communicating branch from the facial nerve was confirmed. CONCLUSION: Surgeons should be aware of the posterior auricular sensory branch and its clinical implications.

Temporal Lobe Retraction Provides Better Surgical Exposure of the Peri-Geniculate Ganglion for Facial Nerve Decompression via Transmastoid Approach.

PURPOSE: For the exposure of the labyrinthine segment of the facial nerve, transmastoid approach is not usually considered due to being situated behind the superior semicircular canal. To obtain a better view and bigger field for manipulation in the peri-geniculate area during facial nerve decompression, retraction of temporal lobe after bony removal of tegmen mastoideum was designed via transmastoid approach. MATERIALS AND METHODS: Fifteen patients with traumatic facial paralysis [House-Brackmann (HB) grade IV-VI], 3 patients with Bell's palsy (HB grade V-VI), and 2 patients with herpes zoster oticus (HB grade V-VI) underwent facial nerve decompression surgery between January 2008 and July 2014. In all patients, we performed temporal lobe retraction for facial nerve decompression via the transmastoid approach. Patients were examined using pre operative tests including high-resolution computed tomography, temporal magnetic resonance imaging, audiometry, and electroneurography (degenerative ratio >90%). Facial function was evaluated by HB grading scale before and 6 months after the surgery. RESULTS: After the surgery, facial function recovered to HB grade I in 9 patients and to grade II in 11 patients. No problems due to surgical retraction of the temporal lobe were noted. Compared to the standard transmastoid approach, our method helped achieve a wider surgical view for improved manipulation in the peri-geniculate ganglion in all cases. CONCLUSION: Facial nerve decompression via the transmastoid approach with temporal lobe retraction provides better exposure to the key areas around the geniculate ganglion without complications.

Synchronous presentation of trigeminal, glossopharyngeal and geniculate neuralgias in a single patient.

Orofacial pain disorders can present as a diagnostic and therapeutic challenge for oral health care providers. Odontogenic and nonodontogenic sources of orofacial pain should be considered and cranial neuralgias may be included in the differential diagnosis. Synchronous presentation of multiple cranial neuralgias is a rare occurrence. We report a case of a patient with a synchronous presentation of trigeminal, glossopharyngeal, and geniculate neuralgias. To our knowledge, this is the first case of a synchronous presentation of these conditions reported to date.

Calcium Phosphate Cement Cranioplasty Decreases the Rate of Cerebrospinal Fluid Leak and Wound Infection Compared with Titanium Mesh Cranioplasty: Retrospective Study of 672 Patients.

OBJECTIVE: A variety of biomaterials have been developed for cranial reconstruction after craniectomy, including polyethylene titanium mesh and calcium phosphate cement. This study sought to compare complication rates of calcium phosphate cement and titanium mesh cranioplasty in patients undergoing retromastoid craniectomy. METHODS: The authors retrospectively reviewed clinical data from 672 consecutive patients who underwent retromastoid craniectomy at a single institution for microvascular decompression or tumor resection from July 2009 to July 2014. Of these, 336 patients received calcium phosphate cement cranioplasty and 336 underwent (polyethylene) mesh cranioplasty. Charts were abstracted for occurrence of cerebrospinal fluid (CSF) leak, wound infection and/or other wound complication, and the groups were compared. RESULTS: In the mesh cranioplasty group, there were 38 complications related to the surgical site, including 18 infections (5.4%), 20 patients (6%) with CSF leak or pseudomeningocele, and no (0%) other wound complications. In the cement cranioplasty cohort, 2 patients (0.6%) experienced wound infection, no patients (0%) had CSF leak, and 2 patients (0.6%) had other wound complications (including one sterile wound dehiscence and one reoperation for removal of excess cement). There was a statistically significant decrease in the rate of wound infection and CSF leak in the patients who underwent cement cranioplasty (P <0.001 for both). CONCLUSIONS: Calcium phosphate cement cranioplasty offers an alternative to titanium cranioplasty and may reduce the risk of surgical site complication. Randomized, prospective comparisons of cement cranioplasty to traditional techniques are warranted.

The incidence of high-frequency hearing loss after microvascular decompression for trigeminal neuralgia, glossopharyngeal neuralgia, or geniculate neuralgia.

OBJECT: The primary aim of this study was to evaluate the incidence and discuss the pathogenesis of high-frequency hearing loss (HFHL) after microvascular decompression (MVD) for trigeminal neuralgia (TGN), glossopharyngeal neuralgia (GPN), or geniculate neuralgia (GN). METHODS: The authors analyzed preoperative and postoperative audiogram data and brainstem auditory evoked potentials (BAEPs) from 93 patients with TGN, 6 patients with GPN, and 8 patients with GN who underwent MVD. Differences in pure tone audiometry > 10 dB at frequencies of 0.25, 0.5, 1, 2, 4, and 8 kHz were calculated preoperatively and postoperatively for both the ipsilateral and the contralateral sides. Intraoperative monitoring records were analyzed and compared with the incidence of HFHL, which was defined as a change in pure tone audiometry > 10 dB at frequencies of 4 and 8 kHz. RESULTS: The incidence of HFHL was 30.84% on the side ipsilateral to the surgery and 20.56% on the contralateral side. Of the 47 patients with HFHL, 20 had conductive hearing loss, and 2 experienced nonserviceable hearing loss after the surgery. The incidences of HFHL on the ipsilateral side at 4 and 8 kHz were 17.76% and 25.23%, respectively, and 8.41% and 15.89%, respectively, on the contralateral side. As the audiometric frequency increased, the number of patients with hearing loss increased. No significant postoperative difference was found between patients with and without HFHL in intraoperative BAEP waveforms. Sex, age, and affected side were not associated with an increase in the incidence of hearing loss. CONCLUSIONS: High-frequency hearing loss occurred after MVD for TGN, GPN, or GN, and the greatest incidence occurred on the ipsilateral side. This hearing loss may be a result of drill-induced noise and/or transient loss of cerebrospinal fluid during the course of the procedure. Changes in intraoperative BAEP waveforms were not useful in predicting HFHL after MVD. Repeated postoperative audiological examinations may be useful in assessing the prognosis of HFHL.

Geniculate neuralgia: clinical, radiologic, and intraoperative correlates.

OBJECTIVE: Geniculate neuralgia is an uncommon pain syndrome that can be severe and disabling and is difficult to diagnose. METHODS: The literature was reviewed for geniculate neuralgia, including anatomy, presentation, and treatment. A case illustration was presented that demonstrates the novel brainstem functional imaging findings for geniculate neuralgia. A 39-year-old man presented with a history of left "deep" ear pain within his ear canal. He noted occasional pain on the left side of his face around the ear. He had been treated with neuropathic pain medications without relief. His wife described suicidal ideations discussed by her husband because of the intense pain. RESULTS: The patient's neurologic examination was normal, and otolaryngologic consultation revealed no underlying structural disorder. Anatomic imaging revealed a tortuous vertebral artery-posterior inferior cerebellar artery complex with the posterior inferior cerebellar artery loop impinging on the root entry zone of the nervus intermedius-vestibulocochlear nerve complex and just inferior to the root entry zone of the facial nerve and a small anterior inferior cerebellar artery loop interposed between the cranial nerve VII-VIII complex and the hypoglossal and glossopharyngeal nerves. A left-sided retromastoid craniotomy was performed, and the nervus intermedius was transected. An arterial loop in contact with the lower cranial nerves at the level of the brainstem was mobilized with a polytetrafluoroethylene implant. CONCLUSIONS: The patient indicated complete relief of his preoperative pain after surgery. He has remained pain-free with intact hearing and balance.

The nervus intermedius: a review of its anatomy, function, pathology, and role in neurosurgery.

BACKGROUND: Geniculate neuralgia, although uncommon, can be a debilitating pathology. Unfortunately, a thorough review of this pain syndrome and the clinical anatomy, function, and pathology of its most commonly associated nerve, the nervus intermedius, is lacking in the literature. Therefore, the present study aimed to further elucidate the diagnosis of this pain syndrome and its surgical treatment based on a review of the literature. METHODS: Using standard search engines, the literature was evaluated for germane reports regarding the nervus intermedius and associated pathology. A summary of this body of literature is presented. RESULTS: Since 1968, only approximately 50 peer-reviewed reports have been published regarding the nervus intermedius. Most of these are single-case reports and in reference to geniculate neuralgia. No report was a review of the literature. CONCLUSIONS: Neuralgia involving the nervus intermedius is uncommon, but when present, can be life altering. Microvascular decompression may be effective as a treatment. Along its cisternal course, the nerve may be difficult to distinguish from the facial nerve. Based on case reports and small series, long-term pain control can be seen after nerve sectioning or microvascular decompression, but no prospective studies exist. Such studies are now necessary to shed light on the efficacy of surgical treatment of nervus intermedius neuralgia.

Initial lesions in Bell's palsy and Ramsay-Hunt syndrome.

CONCLUSION: The antidromic facial nerve response (AFNR) revealed that the initial lesion in both Bell's palsy and Hunt syndrome was mainly located around the geniculate ganglion within 1 week after onset of paralysis. The preoperative AFNR reflected the response near the initial lesion. OBJECTIVES: To review the initial lesion in Bell's palsy and Ramsay-Hunt syndrome using intraoperative monitoring of the AFNR. METHODS: 15 patients, including 8 with Bell's palsy and 7 with Ramsay-Hunt syndrome, were checked for the AFNR before and during transmastoid decompression surgery within 1 week after onset of paralysis. The AFNR monitoring was performed at the posterosuperior part of the anulus tympanicus preoperatively and at 4 points of the facial nerve during surgery. The nerve conduction block sites were diagnosed by the AFNR waveform. RESULTS: The monophasic wave revealing the block site was mainly observed at the geniculate ganglion in both diseases. The latencies of the preoperative responses corresponded to those recorded intraoperatively around the pyramidal segment of the facial nerve.

Effect of delayed decompression after early steroid treatment on facial function of patients with facial paralysis.

CONCLUSION: The earlier decompression is carried out, the better the result. However, decompression delayed a few days beyond 2 weeks after onset of facial paralysis can benefit the recovery of facial function in patients when combined with early use of steroids with or without antiviral agents. OBJECTIVES: To demonstrate the correlation between the time of decompression after the onset of facial paralysis and the facial function after surgery and elucidate the beneficial effect of decompression delayed a few days beyond the 2 week period on recovery of facial function in patients who had received early steroid treatment. PATIENTS AND METHODS: Between April 1994 and December 2007, 91 patients with complete facial paralysis who had received early treatment with steroid with or without antiviral agents were included in the study. An independent sample t test was used to analyze the recovery of facial function in patients receiving surgical decompression at different times after onset of paralysis and medical treatment only. RESULTS: Functional gain according to the House-Brackman (HB) grade was 4.05+/-0.96 for early decompression, 3.63+/-0.58 for delayed decompression, 2.90+/-0.76 for late decompression, and 2.51+/-0.85 for medical treatment only. Delayed decompression significantly improved the functional outcome of patients compared with late decompression and medical treatment only (p<0.05).

Correlation between enhanced MRI and surgical findings in herpes zoster oticus.

CONCLUSION: This study demonstrates good correlation between enhanced MRI and surgical findings. OBJECTIVES: This study investigated the reliability of enhanced magnetic resonance imaging (MRI) to make a surgical decision on the strategy for facial nerve decompression in herpes zoster oticus, by determining the degree of correlation between contrast enhancement in MRI and the pathologic change in the facial nerve. SUBJECTS AND METHODS: This retrospective study of 13 patients, who underwent facial nerve decompression with herpes zoster oticus, was designed to compare gadolinium-enhanced segment of facial nerve on MRI and the pathologically changed segment confirmed by surgical exploration, grouping them by the timing of operation after onset of facial paralysis. RESULTS: Commonly enhanced segments on MRI were the labyrinthine, intracanalicular, and geniculate ganglion, found in 84%, 69%, and 69% of all patients, respectively. The most common pathologic segment was the labyrinthine segment (92%), followed by the geniculate ganglion (84%).