Endoscopic Microvascular Decompression.

Microvascular decompression is a widely accepted surgical treatment for compressive cranial nerve pathologies such as trigeminal neuralgia, hemifacial spasm, glossopharyngeal neuralgia, and other craniofacial pain syndromes. Endoscopy has risen as a safe and effective minimally invasive tool to optimize microvascular decompression. Endoscopy offers improved visualization, minimizes retraction, and allows for smaller surgical openings compared to traditional microscopic approaches. There are several reports of improved neuralgia outcomes and reduced post-operative complications after endoscopic microvascular decompression. In skilled surgical hands, endoscopy is an excellent option for microvascular decompression as stand-alone tool or adjunct to the microscope. An overview of the history, operative considerations, and techniques is provided in this chapter.

Current and future therapies for persistent corneal epithelial defects and neurotrophic keratopathy.

PURPOSE OF REVIEW: The corneal epithelium is a crucial barrier against pathogens, and when disrupted in the setting of certain underlying risk factors such as neurotrophic keratopathy (NK), may result in persistent epithelial defects (PEDs) of the cornea. Management is challenging and may require a variety of different approaches ranging from conservative medical therapy to surgical intervention. The purpose of this review is to provide an update on current and potential future therapeutic options for PEDs and NK. RECENT FINDINGS: Recent research has yielded promising results for numerous novel therapies aimed at treating PEDs. Many of these attempt to stimulate healing at the cellular level, via signaling of corneal epithelial differentiation, migration, and proliferation. Considerable advances have also been made regarding medical and surgical promotion of corneal re-innervation and restoration of corneal sensitivity to directly address the underlying NK condition. SUMMARY: Together with the current well established therapeutic options available for PEDs and NK, growing research on newer alternatives suggest increasing potential for both more effective and more convenient therapies for these difficult situations.

Nationwide Shift From Percutaneous Rhizotomy to Microvascular Decompression for Treatment of Trigeminal and Other Cranial Nerve Neuralgias.

OBJECTIVE: The aim of this study was to report the trends in the use of common surgical interventions over the past decade to treat cranial nerve neuralgias. METHODS: The Centers for Medicare and Medicaid Services Part B National Summary Data File from 2000 to 2016 were studied. RESULTS: A total of 57.1 million persons were enrolled in 2016, up from 39.6 million persons in 2000. Suboccipital craniectomy done for cranial nerve decompressions (including cranial nerves V, VII, and IX) increased by 33.9 cases per year so that in 2016 the number of cases was 167% of what it was 17 years earlier (ie, from 655 cases in 2000 to 1096 cases in 2016). The less commonly used subtemporal approach craniectomy to treat trigeminal neuralgia (TN) increased by 1.13 cases per year (ie, from 25 cases in 2000 to 46 cases in 2016). The less invasive percutaneous rhizotomy procedures, including glycerol and radiofrequency ablation, for treatment of TN decreased by 42.9 cases per year (64%; ie, from 2578 cases in 2000 to 1206 cases in 2016). CONCLUSIONS: Overall trends show increased use of open surgery and decreased use of percutaneous rhizotomy, including destruction of the trigeminal nerve using balloon compression, glycerol injection, or thermal injury. These trends may be related to differences in outcomes between treatment modalities.

Bilateral Internal Carotid Artery Aneurysms at the Subpetrosal Portion with Unilateral Lower Cranial Nerve Palsies: Review and Consideration of Surgical Strategy.

BACKGROUND: Symptomatic bilateral extracranial internal carotid artery (ICA) aneurysms at the subpetrosal portion are extremely rare, and their treatment strategy remains unknown. CLINICAL PRESENTATION: A 42-year-old man presented to our hospital with a 2-month history of sudden onset of hoarseness, dysarthria, and dysphagia. Magnetic resonance imaging, magnetic resonance angiography, and computed tomography angiography revealed extracranial bilateral ICA aneurysms at the subpetrosal portion. The left-sided aneurysm compressed the left-sided lower cranial nerves (IX, X, XI, and XII), whereas the right-sided aneurysm was asymptomatic. We prioritized the treatment of the right-sided aneurysm to prevent bilateral lower cranial nerve deficits. This strategy was used because aneurysm treatment is not guaranteed to cure the left-sided cranial nerve palsies that lasted for 2 months. The right-sided ICA aneurysm was treated with ICA ligation and high-flow extracranial-intracranial bypass using the radial artery as bypass graft. Stent-assisted coil embolization was performed to the left-sided ICA aneurysm after 17 days. The patient showed no right-sided symptoms, and his left-sided symptoms remarkably improved 1 year after surgery. CONCLUSION: Our unique surgical strategy of prioritizing the aneurysm on the "asymptomatic" side may be one of the best treatment approaches in an extremely rare bilateral aneurysm case.

Sumatriptan improves postoperative quality of recovery and reduces postcraniotomy headache after cranial nerve decompression.

BACKGROUND: Microvascular decompression (MVD) is a surgical treatment for cranial nerve disorders via a small craniotomy. The postoperative pain of this procedure can be classified as surgical site somatic pain and postcraniotomy headache similar in nature to a migraine, including its association with photophobia, nausea, and vomiting. This headache can be difficult to treat and can impact on postoperative recovery. Sumatriptan is used to treat migraine-like headaches in various settings. This single-centre randomized controlled trial investigated whether postoperative administration of sumatriptan after MVD surgery impacts the quality of postoperative recovery. METHODS: Fifty patients who complained of postoperative headache after MVD were randomized to receive an s.c. injection of sumatriptan (6 mg) or saline. The primary outcome was quality of recovery as measured by the Quality of Recovery-40 (QoR-40) score at 24 h. RESULTS: The QoR-40 scores were significantly higher in the sumatriptan group (median 184; interquartile range 169-196) than in the placebo group (133; 119-155; P<0.01), suggesting higher quality of recovery. The sumatriptan group also had significantly lower headache scores at 4, 12, and 24 h. There were no significant differences in other secondary outcomes. CONCLUSIONS: Use of sumatriptan improved the quality of recovery as measured by the QoR-40 and reduction of headache at 24 h after surgery. Sumatriptan is a useful alternative treatment for postcraniotomy headache. The mechanism remains unknown but could be related to reduction in headache, mood modulation, or both, mediated by a serotonin effect. CLINICAL TRIAL REGISTRATION: NCT01632657.

Ventral foramen magnum neurenteric cysts: a case series and review of literature.

Neurenteric cysts (NEC) are uncommon, benign, congenital lesions. Ventral foramen magnum (FM) location is very rare. The difficulties in diagnosis and management aspects are detailed with a review of the pertinent literature. We report four new cases of ventral FM NEC, all managed surgically and present a literature review of ventral FM NEC. A retrospective analysis of histopathologically confirmed cases of ventral FM NEC, operated from 2010-2013 at our institute, was performed. For review, only those cases of NEC extending from the lower clivus to the C2 level constituting the foramen magnum were included. Including our four cases, a total of 47 cases were identified. The male to female ratio was 1.2:1. Mean age was 33.5 years (range 1-60 years). Neck pain and occipital headache were the most common symptoms, followed by limb weakness and cranial nerve paresis. Recurrent meningitis was noted in three cases. Hyperintensity on both T1- and T2-weighted sequences with absent enhancement was the most common finding on MRI. Surgical approaches were as follows: suboccipital (n = 21), far/extreme lateral (n = 18), retrosigmoid (n = 6), and transoral (n = 4). The extent of resection was as follows: total, 26; near total, 6; subtotal, 9; and partial, 3 cases. Cerebrospinal fluid diversion was done in four cases for intracranial hypertension. Mean follow-up duration was 26.8 months (range 1 month-9 years). Recurrence was noted in four (8.5 %) cases. One (2 %) case had malignant transformation. Mortality rate was 4 %. Foramen magnum neurenteric cysts are rare, benign tumors of the central nervous system. Accurate preoperative diagnosis can often be established with MRI. Surgical removal is the treatment of choice. Complete excision is ideal but often not possible. Near total removal would suffice with good progression-free periods. A long-term follow-up with radiological studies is necessary as delayed recurrences can occur.

Nerve Sharing Between the Lingual and Mental Nerve to Restore Lower Lip Sensation After Segmental Resection of the Mandible.

This report demonstrates a successful new procedure for reconstructing the inferior alveolar nerve by transplanting the great auricular nerve (GAN) between the mental nerve and the remaining submandibular ganglion to achieve nerve sharing of the lingual nerve. A 59-year-old woman with discomfort in the left mandibular retromolar region and ipsilateral neck was referred to our hospital by a local dentist. Physical examination showed mild swelling and redness at the left mandibular retromolar region. The histologic diagnosis showed central mucoepidermoid carcinoma of the jaw. With the patient under general anesthesia, segmental resection of the mandible followed by level 1 selective neck dissection was performed. The resected mandible was reconstructed with a titanium plate. The submandibular incision was extended to the lower edge of the tragus for harvesting of the GAN. The GAN was grafted, and an epineural neurorrhaphy was carried out with the mental nerve, as well as the submandibular ganglion, under a microscope. After the operation, submental sensation was evaluated with a Semmes-Weinstein pressure esthesiometer. The Semmes-Weinstein pressure esthesiometer test showed a loss of perception at the third week after surgery. Within 12 months, nerve sensation was substantially improved and the patient was free from discomfort.

Immunoglobulin G4-related disease of the orbital cavity, cervical lymph nodes and greater auricular nerve: case report.

IgG4-related disease (IgG4-RD) is a novel clinicopathological entity characterised by elevated tissue levels of IgG4-positive plasma cells. It can present in almost every organ systems. We present a case of a 48year-old man with recurrent intra-orbital and cervical lymph node swelling and found to have greater auricular nerve involvement intraoperatively during open surgical biopsy. Histopathological evaluation of biopsied specimens from these lesions yielded IgG4-positive plasma cell infiltration on immunohistochemistry. Key pathological features such as prominent lymphoplasmacytic population, storiform fibrosis and obliterative phlebitis were also seen. A diagnosis of IgG4-RD was made. Oral prednisone therapy ameliorated the symptoms and patient remained in remission at followup. Literature review indicated that IgG4-RD is a rare condition that seldom occurs concurrently in the orbital cavity, cervical lymph nodes and involving the greater auricular nerve. The condition may often masquerade as malignancy or infection due to formation of tumefactive lesions but tend to respond favourably to glucocorticoid or immunosuppressants. The differential diagnosis of unusual mass lesions in these locations should include IgG4-RD. The otolaryngologist, as well as other health professionals, should be familiar with this novel disease to ensure timely diagnosis and treatment.

Surgical anatomy of the ansa cervicalis nerve: which branch to use for laryngeal reinnervation in humans?

PURPOSE: The aim of this study has been to obtain some data for the selection of which branch of the ansa cervicalis nerve (AC) could be an attractive candidate for a laryngeal reinnervation using AC to recurrent laryngeal nerve (RLN) neurorrhaphy. METHODS: The AC was dissected in ten human head cadavers with an operating microscope. A vagal nerve stimulation was conducted during a bilateral thyroidectomy with normal vocal fold mobility in ten patients using a NIM Medtronic System(®) to record phasic activity within the thyroarytenoid muscle (vocal fold adduction) and one of the infrahyoid muscle (sternothyroid muscle or sternohyoid muscle). RESULTS: Despite reported variations of the roots of AC and location of its loop, the lower portion of the STM and SHM was innervated by a prominent common trunk in 80 % of cases, in a close vicinity of the RLN with an excellent size match to the RLN for a tension-free anastomosis. The STM displays slight but significant electrical activity during vocal fold adduction. CONCLUSION: The common trunk of the SHM and STM is the prime choice for laryngeal reinnervation using AC-RLN non-selective anastomosis. If the main trunk is missing, the branch to the STM can be an attractive candidate.

[Effects of Endovascular Treatment on Cranial Nerve Palsy due to Unruptured Intracranial Aneurysms].

This study aimed to assess the effects of endovascular treatment on cranial nerve palsy due to unruptured intracranial aneurysms. Endovascular coiling was performed in 203 patients with intracranial aneurysms between April 2002 and March 2012 in our hospital. Of these patients, 8(3.9%)presented with cranial nerve palsy due to unruptured intracranial aneurysms. Cranial nerve palsy involved the oculomotor nerve in 8 patients and the optic nerve in 2 patients. Two patients had both optic nerve and oculomotor nerve dysfunction. Patients with incomplete oculomotor nerve palsy at admission were more likely to have full recovery after coiling. Optic nerve dysfunction did not improve after coiling. Incomplete oculomotor nerve palsy, early treatment(≤15 days), and small aneurysms(≤10 mm)were likely to be associated with complete recovery after coiling. This study indicates that endovascular coiling may resolve cranial nerve palsy due to unruptured intracranial aneurysms in patients who have incomplete oculomotor nerve palsy due to small aneurysms and are treated as early as possible after symptom onset.

[Vagal Nerve Schwannoma Complicated with Bloody Pleural Effusion；Report of a Case].

A 51-year-old male who had received hemodialysis twice a week was referred to our hospital for a further examination of bloody pleural effusion in the right chest. He has been suffering from a fever and cough for 2 months. Chest computed tomography and magnetic resonance imaging revealed a pleural effusion in the right pleural cavity and posterior mediastinal tumor in paravertebral lesion. Chest drainage was performed, and cytological diagnosis did not show malignant findings. To make a definite diagnosis and treatment, surgical resection was carried out. During surgery, posterior mediastinal tumor originated from vagal nerve, and a schwannoma was diagnosed by frozen section. After resection, postoperative course was uneventful, and bloody pleural effusion disappeared.

Pituitary apoplexy: managing the life-threatening condition associated with pituitary adenomas.

Pituitary tumor apoplexy is one of a few life-threatening conditions in patients with pituitary adenomas. The very low incidence of this complication hinders formulation of widespread guidelines on diagnostic and therapeutic management. This article presents current opinions on epidemiology, risk factors, clinical signs and symptoms, also the difficulties in selecting appropriate therapeutic management. The paper has focused particularly on making decisions regarding surgical or conservative treatment in pituitary tumor apoplexy. Also the consequences of these decisions based on the key literature references. The article presents endocrine and neuro-ophthalmic consequences of previous pituitary tumor apoplexy with the key management principles for the follow-up period.

Surgical neurolysis for the treatment of neuropathic pain in 2 postmenopausal women with mandibular necrosis resulting from oral bisphosphonates.

We analyze the use of surgical neurolysis for the treatment of neuropathic pain of the inferior alveolar nerve. For that, 3 surgical neurolysis were performed on 2 postmenopausal women experiencing neuropathic pain of the inferior alveolar nerve due to mandibular necrosis resulting from treatment with oral bisphosphonates. Both patients showed sensory impairment of the inferior alveolar nerve. We obtained complete control of neuropathic pain after 6 months of the patients' evolution, preserving the function of the lingual nerve in all 3 neurolysis, without causing any impact as regards to the sensitive situation before treatment. Surgical neurolysis of the inferior alveolar nerve may be considered as the choice therapeutic technique to treat neuropathic pain of this nerve when there is a sensory impairment in patients showing mandibular necrosis resulting from bisphosphonates.

[Intrapituitary adenoma metastasis from lung cancer with progressive cranial nerve palsies: a case report and literature review].

We report a rare case of metastasis to a preexisting pituitary adenoma. An 80-year-old man with a history of pituitary adenoma and lung cancer presented with recent onset of bilateral visual impairment, oculomotor nerve palsies, and severe headache. A CT scan revealed a pituitary tumor expanding into the suprasellar region and infiltrating the bilateral cavernous sinuses. We performed transsphenoidal surgery and diagnosed the tumor as lung cancer metastasis to the pituitary adenoma. After the surgery, visual impairment and severe headache were resolved, and the patient underwent radiation therapy for the residual tumor. To the best of our knowledge, 20 cases of metastases to pituitary adenomas have been reported in the literature. Clinical features of metastasis to a pituitary adenoma are different from those of metastasis to normal pituitary gland. In the case of a pituitary lesion with acute aggravation, one should be aware of the possibility of metastasis to preexisting pituitary adenomas.

The utility of calcium phosphate cement in cranioplasty following retromastoid craniectomy for cranial neuralgias.

BACKGROUND: Following retromastoid craniectomy for microvascular decompression of the fifth or seventh cranial nerve, the preferred method and value of cranioplasty remains disputed. METHODS: In this study, we report the functional outcome of calcium phosphate cranioplasty following first-time microvascular decompression in 79 consecutive patients who underwent operations over a one-year period. RESULTS: No patient experienced a deep infection, cerebrospinal fluid leak or undue incisional pain at long-term follow-up. Additionally, all patients stated that they were satisfied with the cosmetic outcome. DISCUSSION: Although this technique is unlikely to affect the rates of infection and postoperative pain, we believe that the low rate of CSF leak provides a unique advantage over other currently used methods of closing retromastoid craniectomies.

[Protection of the superior petrosal vein in microneurosurgery for acoustic neuroma].

OBJECTIVE: To explore the clinical significance of the protection of superior petrosal vein (SPV) in the microneurosurgery for acoustic neuroma. METHODS: From January 2009 to July 2011, 149 cases of acoustic neuroma microsurgery were observed. The difference in hematoma in surgical area, cerebellar hematoma and cerebellar edema were compared between a SPV without protection group (SPVWP group, n=8) and a SPV protection group (SPVP group, n=141). RESULTS: In the 149 patients with acoustic neuroma, the SPV was reserved in 141 patients. In the SPVWP group (8 patients), hematoma in the surgery area occurred in 4 patients, cerebellar edema in 5, and cerebellar hemorrhage in 3. In the SPVP group (141 patients), hematoma in the surgery area occurred in 40 patients, cerebellar edema in 56, and cerebellar hemorrhage in 12. There was significant difference in the incidence of cerebellar hemorrhage (χ(2)=3.84, P=0.05), no significant difference in the incidence of hematoma in the surgical area (χ(2)=0.646, respectively, P=0.422), and no significant difference in the incidence of cerebellar edema (χ(2)=0.611, P=0.434) between the SPVWP group and the SPVP group. CONCLUSION: In acoustic neuroma surgery, the SPV should be protected, which may reduce the risk of cerebellar hemorrhage.

Clinical Features of Pituitary or Parasellar Tumor Onset with Cranial Nerve Palsy: Surgical Intervention Considerations.

OBJECTIVE: This study aimed to clarify the symptoms of pituitary or parasellar tumor onset with cranial nerve palsy (CNP) and to improve our knowledge of this rare symptom and its most appropriate treatment. METHODS: Among 1281 patients with pituitary or parasellar tumors surgically treated from 2003 to 2020, 30 cases (2.34%; 15 men and 15 women; mean age: 55.6 years, range: 6-83 years) first presenting with CNP were reviewed to evaluate the neurological symptoms, histological diagnosis, interval from onset to surgery, and time before complete CNP recovery. RESULTS: Pathological diagnoses comprised 17 pituitary adenomas, including 10 pituitary apoplexies and 4 adrenocorticotropic hormone-positive adenomas, and 13 other tumors, including 3 chordomas, 2 xanthogranulomas, 2 malignant lymphomas, 2 metastatic tumors, 1 Rathke cleft cyst, 1 plasmacytoma, 1 craniopharyngioma, and 1 neuroendocrine carcinoma. The mechanisms causing CNP were pituitary apoplexy (n = 10), cranial nerve compression or involvement (n = 17), and inflammatory changes (n = 9). As the first manifestation, 20 (66.7%) patients presented with oculomotor nerve palsy, 2 (6.7%) with trochlear nerve palsy, and 13 (43.3%) with abducens nerve palsy. Full recovery of CNP was obtained in 25 patients (83.3%) after surgery alone and in 2 patients (6.7%) after adjuvant therapy. Early surgery provided no significant difference in full recovery rates although it reduced the time to reach full recovery. CONCLUSIONS: It is critical to determine the mechanisms of CNP and intervene surgically to improve symptoms, shorten the duration of the disorder, prevent relapses, and obtain the correct pathological diagnosis to select the proper adjuvant therapy.

Treatment modalities of neurosensory deficit after lower third molar surgery: a systematic review.

PURPOSE: To conduct a systematic review to answer the clinical question, "What are the available treatment modalities and their outcomes of neurosensory deficit after lower third molar surgery?" MATERIALS AND METHODS: A systematic search, including a computer search of several databases with specific keywords, a reference search, and a manual search of 3 key maxillofacial journals were performed. Relevant articles were then evaluated and those that fulfilled the 6 predetermined criteria were chosen to enter the final review. The various treatment modalities and their outcomes of neurosensory deficit after lower third molar surgery, in the selected studies in the final review, were analyzed. RESULTS: Ten articles entered the final review. Six treatment modalities of lingual nerve or inferior alveolar nerve deficit after lower third molar surgery were identified. External neurolysis, direct suturing, autogenous vein graft, and a Gore-Tex tube as a conduit were the 4 surgical treatments. Significant improvement after surgical treatment ranged from 25% to 66.7%. Acupuncture and low-level laser therapy were 2 available nonsurgical treatment modalities that were found to have produced significant improvement in sensation after treatment in more than 50% of subjects. There was insufficient information to determine the best timing of treatment of nerve injury after third molar surgery. CONCLUSIONS: Four surgical treatments and 2 nonsurgical treatments were identified in the management of neurosensory disturbance after lower third molar surgery. Most treatments showed an improvement in sensation but the outcomes were variable. Complete recovery was uncommon in all kinds of available treatments.

[Dexmedetomidine is an excellent sedative for voice monitoring surgery].

We experienced anesthesia for three cases of unilateral recurrent nerve palsy scheduled for thyroplasty type I requiring voice monitoring. The patients were sedated with dexmedetomidine and locally anesthetized. Dexmedetomidine provided sedation of high quality with natural sleep, good response to asking for phonation and very few respiratory depressions. We conclude that dexmedetomidine is an excellent sedative as a drug used for voice monitoring surgery.

Microvascular Decompression: A Bibliometric Analysis of the 100 Most Cited Articles.

OBJECTIVE: Bibliometric analyses assess the impact and influence of articles in the academic community. There is no previous work that has used bibliometric analysis of microvascular decompression (MVD). This study aims to identify and characterize the 100 most cited articles on MVD. METHODS: Highly cited articles were identified assessing the Scopus library by using the keywords "microvascular decompression," "MVD," "nerve decompression," "nerve root decompression," and "microvascular surgery." Data were further processed by sampling techniques with defined inclusion and exclusion criteria. The number of citations, country of origin, institutions of origin, year of publication, type of cranial nerve disorder, type of article, and the publishing journal were analyzed. Further, article categories and the type of studies were investigated. RESULTS: The 100 most cited articles on MVD ranged from 951 to 76 total citations, and from 38.04 to 1.88 citations per year. Publication dates spanned a period from 1959 to 2015. The most frequently studied cranial nerve disorder was trigeminal neuralgia (n = 54). Articles were published in 29 journals, with Neurosurgery (n = 33) topping the list. The articles came from 14 different countries, with most contributions from the United States (n = 55). Authors of the highly cited articles who received most citations were Peter J. Jannetta (n = 26), followed by Aage Møller (n = 13), and Marc Sindou (n = 11). CONCLUSIONS: This work provides a detailed evaluation of the 100 most cited articles on MVD, thus allowing recognition and selected reading of the most influential academic contributions related to this surgical technique in a variety of cranial nerve disorders.