Axon degeneration and regeneration: insights from Drosophila models of nerve injury.

Axon degeneration is the pivotal pathological event of acute traumatic neural injury as well as many chronic neurodegenerative diseases. It is an active cellular program and yet molecularly distinct from cell death. Much effort is devoted toward understanding the nature of axon degeneration and promoting axon regeneration. However, the fundamental mechanisms of self-destruction of damaged axons remain unclear, and there are still few treatments for traumatic brain injury (TBI) or spinal cord injury (SCI). Genetically approachable model organisms such as Drosophila melanogaster, the fruit fly, have proven exceptionally successful in modeling human neurodegenerative diseases. More recently, this success has been extended into the field of acute axon injury and regeneration. In this review, we discuss recent findings, focusing on how these models hold promise for accelerating mechanistic insight into axon injury and identifying potential therapeutic targets for TBI and SCI.

Mini-Skin Incision for Carotid Endarterectomy: Neurological Morbidity and Health-related Quality of Life.

BACKGROUND: Cranial and cervical nerve (CCN) injury is recognized as a possible complication after carotid endarterectomy (CEA), which may result in minor local neurologic deficiencies and significant discomfort for the patient. The aim of this study is to investigate the effect of a mini-skin incision (<5 cm) on the CCN injury after CEA in comparison to standard longitudinal incision of 12-15 cm in a high volume center, and to evaluate health-related quality of life (HRQOL) outcomes in those patients who had undergone both types of the skin incision. METHODS: From January 2013 to December 2019, 446 CEAs (47.3%) were performed through a standard neck incision of 12-15 cm (group A), while 496 (52.7%) were performed through a mini-skin incision (<5 cm) (group B). Sixty-two patients underwent standard neck incision on one side and mini-skin incision on the other side (subgroup B). The main outcome measures were stroke, death, CCN injuries, cervical hematoma rates, and reinterventions. The HRQOL was assessed at baseline and after 30 days using Medical Outcomes Study Short-Form 36 and 6 disease-specific modified Likert scales. RESULTS: The stroke and death rate at 30 days was 1.12% in group A and 1% in group B (P = 1). The incidence of CCN deficits was significantly lower in group B (5.1%) in comparison to group A (13.4%) (P < 0.001). The cervical hematoma was more common after standard incision (4.9% vs. 1.2%, P = 0.02). HRQOL at 1 month showed that the outcomes after mini-skin incision were significantly better for less difficulty with eating/swallowing and neck pain (P < 0.01). CONCLUSIONS: CEA through a small incision (<5 cm) may reduce CCN complications without additional perioperative neurologic risks. As validated by patients with bilateral disease who experienced both surgical techniques, mini-skin incision is also associated with better HRQOL at 1 month, particularly with regard to eating/swallowing and neck pain.

Cranial Nerve Injury After Carotid Endarterectomy: Incidence, Risk Factors, and Time Trends.

OBJECTIVE/BACKGROUND: To review the incidence of post-carotid endarterectomy (CEA) cranial nerve injury (CNI), and to evaluate the risk factors associated with increased CNI risk. METHODS: The study was a meta-analysis. Pooled rates with 95% confidence intervals (CIs) were calculated for CNIs after primary CEA. Odds ratios (ORs) were calculated for potential risk factors. A fixed-effects model or a random effects model (Mantel-Haenszel method) was used for non-heterogeneous and heterogeneous data, respectively. Meta-regression analysis was performed to examine the influence of publication year upon CNI rate. RESULTS: Twenty-six articles, published between 1970 and 2015, were included in the meta-analysis, corresponding to 20,860 CEAs. Meta-analysis revealed that the vagus nerve was the most frequently injured cranial nerve (pooled injury rate 3.99%, 95% CI 2.56-5.70), followed by the hypoglossal nerve (3.79%, 95% CI 2.73-4.99). Fewer than one seventh of these injuries are permanent (vagus nerve: 0.57% [95% CI 0.19-1.10]; hypoglossal nerve: 0.15% [95% CI 0.01-0.39]). A statistically significant influence of publication year on the vagus and hypoglossal nerve injury rate was found, with the injury rate having decreased from about 8% to 2% and 1%, respectively, over the last 35 years. Urgent procedures (OR 1.59, 95% CI 1.21-2.10; p = .001), as well as return to the operating room for a neurological event or bleeding (OR 2.21, 95% CI 1.35-3.61; p = .002) were associated with an increased risk of CNI, whereas no statistically significant association was found between CNIs and the type of anaesthesia, the use of a patch, redo operation, and the use of a shunt. CONCLUSION: The vagus nerve appears to be the most frequently injured cranial nerve after CEA, followed by the hypoglossal nerve, with only a small proportion of these injuries being permanent. The CNI rate has significantly decreased over the past 35 years to a point indicating that CNIs should not be considered a major influencing factor in the decision making process between CEA and stenting.

Clinical relevance of cranial nerve injury following carotid endarterectomy.

OBJECTIVES: The benefit of carotid endarterectomy (CEA) may be diminished by cranial nerve injury (CNI). Using a quality improvement registry, we aimed to identify the nerves affected, duration of symptoms (transient vs. persistent), and clinical predictors of CNI. METHODS: We identified all patients undergoing CEA in the Vascular Study Group of New England (VSGNE) between 2003 and 2011. Surgeon-observed CNI rate was determined at discharge (postoperative CNI) and at follow-up to determine persistent CNI (CNIs that persisted at routine follow-up visit). Hierarchical multivariable model controlling for surgeon and hospital was used to assess independent predictors for postoperative CNI. RESULTS: A total of 6,878 patients (33.8% symptomatic) were included for analyses. CNI rate at discharge was 5.6% (n = 382). Sixty patients (0.7%) had more than one nerve affected. The hypoglossal nerve was most frequently involved (n = 185, 2.7%), followed by the facial (n = 128, 1.9%), the vagus (n = 49, 0.7%), and the glossopharyngeal (n = 33, 0.5%) nerve. The vast majority of these CNIs were transient; only 47 patients (0.7%) had a persistent CNI at their follow-up visit (median 10.0 months, range 0.3-15.6 months). Patients with perioperative stroke (0.9%, n = 64) had significantly higher risk of CNI (n = 15, CNI risk 23.4%, p < .01). Predictors for CNI were urgent procedures (OR 1.6, 95% CI 1.2-2.1, p < .01), immediate re-exploration after closure under the same anesthetic (OR 2.0, 95% CI 1.3-3.0, p < .01), and return to the operating room for a neurologic event or bleeding (OR 2.3, 95% CI 1.4-3.8, p < .01), but not redo CEA (OR 1.0, 95% CI 0.5-1.9, p = .90) or prior cervical radiation (OR 0.9, 95% CI 0.3-2.5, p = .80). CONCLUSIONS: As patients are currently selected in the VSGNE, persistent CNI after CEA is rare. While conditions of urgency and (sub)acute reintervention carried increased risk for postoperative CNI, a history of prior ipsilateral CEA or cervical radiation was not associated with increased CNI rate.

Microvascular decompression for hemifacial spasm in patients >65 years of age: an analysis of outcomes and complications.

INTRODUCTION: Few data are available to quantify the risks and benefits of microvascular decompression (MVD) in elderly patients with hemifacial spasm. METHODS: Twenty-seven patients >65 years of age and 104 younger patients who underwent MVD for hemifacial spasm (HFS) over a 3-year period were analyzed retrospectively and compared. RESULTS: Twenty-six (96.3%) elderly patients and 93 of 104 (89.4%) young patients reported a spasm-free status at a mean follow-up of 26.5 months after MVD. No significant difference in spasm-free status was noted. Cranial nerve complications and other major complications were compared, with no significant differences observed. CONCLUSIONS: Although this study does not offer definitive inclusion or exclusion criteria or clearly establish the safety of MVD for HFS in the elderly, our experience suggests that many elderly patients with HFS can undergo MVD safely, with outcomes and risk profiles similar to those of younger patients.

Cranial nerve monitoring during subpial dissection in temporomesial surgery.

OBJECTIVE: Cranial nerves (CNs) crossing between the brainstem and skull base at the level of the tentorial hiatus may be at risk in temporomesial surgery involving subpial dissection and/or tumorous growth leading to distorted anatomy. We aimed to identify the surgical steps most likely to result in CN damage in this type of surgery. METHODS: Electromyographic responses obtained with standard neuromonitoring techniques and a continuous free-running EMG were graded as either contact activity or pathological spontaneous activity (PSA) during subpial resection of temporomesial structures in 16 selective amygdalohippocampectomy cases. Integrity of peripheral motor axons was tested by transpial/transarachnoidal electrical stimulation while recording compound muscle action potentials from distal muscle(s). RESULTS: Continuous EMG showed pathological activity in five (31.2%) patients. Nine events with PSA (slight activity, n = 8; strong temporary activity, n = 1) were recorded. The oculomotor nerve was involved three times, the trochlear nerve twice, the facial nerve once, and all monitored nerves on three occasions. Surgical maneuvers associated with PSA were the resection of deep parts of the hippocampus and parahippocampal gyrus (CN IV, twice; CN III, once), lining with or removing cotton patties from the resection cavity (III, twice; all channels, once) and indirect exertion of tension on the intact pia/arachnoid of the uncal region while mobilizing the hippocampus and parahippocampal gyrus en bloc (all channels, once; III, once). CMAPs were observed at 0.3 mA in two patients and at 0.6 mA in one patient, and without registering the exact amount of intensity in three patients. CONCLUSION: The most dangerous steps leading to cranial nerve damage during mesial temporal lobe surgery are the final stages of the intervention while the resection is being completed in the deep posterior part and the resection cavity is being lined with patties. Distant traction may act on nerves crossing the tentorial hiatus via the intact arachnoid.

[Damage to craniocerebral nerves in reconstructive surgery of carotid arteries].

Reconstructive operations on aortic arch branches appear to be the most efficient method of preventing acute and chronic impairments of cerebral circulation. Iatrogenic lesions of the craniocerebral nerves deteriorate the course of the immediate, and especially the remote postoperative period, decreasing quality of life and social status of the patients after endured carotid reconstructions. The authors analysed herein the outcomes in a total of 562 patients after endured carotid artery surgery for atherosclerosis or pathological tortuosity. The authors examined the incidence rate, patterns and risk factor of damage to the craniocerebral nerves in all the patients. Comprehensive prevention of damage to the craniocerebral nerves was carried out in a total of 412 patients from the Study Group and was aimed at excluding or decreasing intensity of the eff ect of the eliminable risk factors. The proposed measures made it possible to decrease the rate of lesions of craniocerebral nerves from 18.7 to 6.9% and to substantially improve the postoperative patients' quality of life.

Sequelae of Major Trauma Patients with Maxillofacial Fractures.

OBJECTIVES: Sequelae after maxillofacial fractures are frequent and may affect the patient's quality of life. This study examined sequelae associated with maxillofacial fractures of severely traumatized patients focusing mainly on nerve injuries. METHODS: A retrospective study including trauma patients with relevant facial fractures admitted to our Trauma Center in the period 2011-2016. Presence of posttraumatic maxillofacial sequelae was identified by examining the medical records of the included patients. Focusing on facial sensory deficits and facial nerve paralysis, but also comprising data on diplopia, blindness, malocclusion, trismus, eye globe malposition, flattening of the malar, facial contour changes, and wound infections. RESULTS: Two-hundred-seventy-five severely traumatized patients were included, comprising 201 men (73%), with a median age of 40 years and ISS of 20. 163 (59%) patients only had assessments within 3 months from trauma of which 79 patients (48.5%) had facial complications at initial examination, mostly malocclusion and trismus. Most patients in this group had no or only minor sequelae at their last clinical assessment, mainly being sensory deficits. 112 (41%) patients had assessments both within and beyond 3 months of which 73 patients (65.2%) had facial complications at initial examination, while 91 patients (81%) had reported sequelae within 3 months decreasing to 47 patients (42%) at their last clinical assessment beyond 3 months from trauma, mostly sensory deficits. An improvement of most sequelae was observed. CONCLUSION: Objective sequelae were found to be quite common after maxillofacial fractures in severely traumatized patients, especially sensory deficits. However, most of the addressed sequelae seemed to improve over time.

Cranial nerve V2 and Vidian nerve trauma secondary to lateral pterygoid recess encephalocele repair.

BACKGROUND: The incidence of adverse sequelae related to trauma of cranial nerve V2 (V2) and the Vidian nerve (VN) during endoscopic pterygoid recess repair (PRR) of lateral sphenoid encephalocele is insufficiently reported in the medical literature. As part of our quality assessment and improvement program we sought to analyze the incidence and severity of V2 and VN injury during a 9-year experience (2010-2018) with PRR. METHODS: Hypoesthesia, paresthesia, and dry eye and their impact on patient quality of life were sought through chart review and a self-reported 0 to 5 Likert scale for each symptom. RESULTS: Thirty-five patients underwent repair of spontaneous cerebrospinal-fluid (CSF) rhinorrhea, with 11 consecutive patients undergoing endoscopic PRR. Mean follow-up for PRR was 32.5 months (range, 2.4 to 103.3 months). Although definitive management resulted in 100% success, 1 required secondary treatment. Eight patients were available for long-term follow-up (72.7%) and completed a symptom severity questionnaire using a Likert-scale. All patients observed either hypoesthesia, paresthesia, or dry eye of varying gradation (scale, 0 to 5). None described disabling symptoms, and some reported gradual improvement. Numbness, paresthesia, and dry eye were reported by 6 of 8 (75%), 5 of 8 (62.5%), and 4 of 8 (50%) patients, respectively. The mean Likert score among the 8 patients who completed this questionnaire noticing hypoesthesia, paresthesia, and dry eye was 2.6, 1.3, and 1.8, respectively. CONCLUSION: Meticulous surgical technique is paramount for successful PRR and minimizing nerve injury, yet the anatomic variation of the lateral pterygoid recess can be challenging, and neural injury is a real risk. Preoperatively, patients should be counseled that although V2 or VN injury is common, most patients describe resulting symptoms to be rarely bothersome.

Cranial nerve outcomes in regionally recurrent head & neck melanoma after sentinel lymph node biopsy.

OBJECTIVE: Characterize long-term cranial nerve (CN) outcomes following sentinel lymph node biopsy (SLNB) based management for head and neck cutaneous melanoma (HNCM). METHODS: Longitudinal review of HNCM patients undergoing SLNB from 1997-2007. RESULTS: Three hundred fifty-six patients were identified, with mean age 53.5 ± 19.0 years, mean Breslow depth 2.52 ± 1.87 mm, and 4.9 years median follow-up. One hundred five (29.4%) patients had SLNB mapping to the parotid basin. Eighteen patients had positive parotid SLNs and underwent immediate parotidectomy / immediate completion lymph node dissection (iCLND), with six possessing positive parotid non-sentinel lymph nodes (NSLNs). Fifty-two of 356 (14.6%) patients developed delayed regional recurrences, including 20 total intraparotid recurrences: five following false negative (FN) parotid SLNB, three following prior immediate superficial parotidectomy, two following iCLND without parotidectomy, and the remaining 12 parotid recurrences had negative extraparotid SLNBs. Parotid recurrences were multiple (4.9 mean recurrent nodes) and advanced (n = 4 extracapsular extension), and all required salvage dissection including parotidectomy. Immediate parotidectomy/iCLND led to no permanent CN injuries. Delayed regional HNCM macrometastasis precipitated 16 total permanent CN injuries in 13 patients: 10 CN VII, five CN XI, and one CN XII deficits. Fifty percent (n = 10) of parotid recurrences caused ≥1 permanent CN deficits. CONCLUSIONS: Regional HNCM macrometastases and salvage dissection confer marked CN injury risk, whereas early surgical intervention via SLNB ± iCLND ± immediate parotidectomy yielded no CN injuries. Further, superficial parotidectomy performed in parotid-mapping HNCM does not obviate delayed intraparotid recurrences, which increase risk of CN VII injury. Despite lack of a published disease-specific survival advantage in melanoma, early disease control in cervical and parotid basins is paramount to minimize CN complications. LEVEL OF EVIDENCE: 4 (retrospective case series) Laryngoscope, 130:1707-1714, 2020.

Development of cranial nerve palsy shortly after endosaccular embolization for asymptomatic cerebral aneurysm: report of two cases and literature review.

CLINICAL DESCRIPTION: We report two cases of asymptomatic cerebral aneurysm in which cranial nerve palsy (CNP) developed shortly after symbolization. The CNP occurred immediately in case 1, but case 2 showed the CNP 30 h after symbolization. Although both aneurysms had increased in size on follow-up angiography, case 2 who showed dome re canalization resulted in progressive CNP deterioration. CONCLUSION: These findings suggest that the CNP may result not only from mechanical compression by coils but also from inflammation induced by perpendicular thrombosis, and that the prognosis of the CNP may be influenced by dome re canalization. This complication should be kept in mind in treatment for asymptomatic aneurysms adjacent to the cranial nerves.

Removal of a chopstick out of the cavernous sinus, pons, and cerebellar vermis through the superior orbital fissure.

Penetrating non-missile orbito cranial injuries are rare in a civilian pediatric setting. We describe a case of a trans-orbital penetration by a wooden chopstick deep down into the cerebellar vermis detected at neuroradiological examination in a child presenting for head injury. The foreign body was successfully pulled out in one piece surgically.

Colon Interposition for Corrosive Esophageal Stricture: Single Institution Experience with 119 Cases.

The colon is an alternative graft organ for esophageal reconstruction. The present study reviewed our experience with the colon interposition for esophageal replacement following corrosive ingestion, to evaluate the outcomes of colon interposition based on our surgical experience. The clinical data of 119 patients who underwent colon interposition for esophageal replacement from January 2005 to March 2017 were retrospectively analyzed. The routes of the colon interposition were retrosternal in 119 (100%). The median operative time was 390 min (range: 290-610 min) and the median blood loss was 615 mL (range: 270-2500 mL). Of these 119 patients, the cervical anastomosis was performed at the hypopharynx (n=20, 16.8%), the larynx (n=3, 2.5%), and the cervical esophagus (n=96, 80.7%). Five patients experienced cervical anastomotic leakage (4 cases for esophagus-colon, and one for hypopharynx-colon). One patient experienced wound infection of the abdominal wall. Three patients had injury of recurrent laryngeal nerve and hoarseness. Three patients had stress ulcer with bleeding and treated with octreotide. Two patients suffered from incomplete intestinal obstruction. The postoperative follow-up was made for 12 months in all patients and all of them were alive. In conclusion, The colon is well-suited for esophageal reconstruction. The selection of the colon graft should be flexible and be based on the inspection of blood supply and the length needed. We must therefore make every effort to reduce the number of postoperative complications, and improve the quality of life for patients.

Effect of SB-750364, a specific TRPV1 receptor antagonist, on injury-induced ectopic discharge in the lingual nerve.

Abnormal neural activity generated at a site of nerve injury is thought to contribute to the development of dysaesthesia. Vanilloid receptor 1 (TRPV1), a transducer of noxious stimuli, may be involved in the initiation of this abnormal activity and could provide a useful therapeutic target. We investigated the effect of a specific TRPV1 antagonist (SB-750364) on injury-induced discharge in the lingual nerve. In 12 anaesthetised adult ferrets the left lingual nerve was sectioned and animals were allowed to recover for 3-7 days. In terminal experiments under general anaesthesia, the nerve was re-exposed and electrophysiological recordings made from spontaneously active axons in fine filaments dissected from the nerve central to both the injury site and the junction with the chorda tympani. SB-750364 was infused via the cephalic vein in order to achieve three increasing but stable systemic blood levels of the compound (0.3, 1.0 and 3.0 microM). Twenty-eight spontaneously active units were studied, with discharge frequencies ranging from 0.02 to 4.9 Hz. There was a significant reduction in spontaneous activity in 17 units (61%) at 1.0 microM or less of SB-750364 (p<0.01; Friedman test with Dunn's multiple comparisons). A further 4 units (14%) showed a significant reduction in activity at 3.0 microM (p<0.01). In the remaining 7 units (25%) the discharge was unaffected (p>0.05). These data show that the TRPV1 antagonist SB-750364 can reduce the level of spontaneous activity initiated in some axons following lingual nerve injury.

Surgical anatomy of the external branch of the superior laryngeal nerve and its clinical significance in head and neck surgery.

Injury of the external branch of the superior laryngeal nerve (EBSLN) increases the morbidity following a variety of neck procedures and can have catastrophic consequences in people who use their voice professionally. Identification and preservation of the EBSLN are thus important in thyroidectomy, parathyroidectomy, carotid endarterectomy, and anterior cervical spine procedures, where the nerve is at risk. There are large variations in the anatomical course of the EBSLN, which makes the intraoperative identification of the nerve challenging. The topographic relationship of the EBSLN to the superior thyroid artery and the upper pole of the thyroid gland are considered by many authors to be the key point for identifying the nerve during surgery of the neck. The classifications by Cernea et al. ([1992a] Head Neck 14:380-383; [1992b] Am. J. Surg. 164:634-639) and by Kierner et al. ([1998] Arch. Otolaryngol. Head Neck Surg. 124:301-303), as well as clinically important connections are discussed in detail. Along with sound anatomical knowledge, neuromonitoring is helpful in identifying the EBSLN during neck procedures. The clinical signs of EBSLN injury include hoarseness, decreased voice projection, decreased pitch range, and fatigue after extensive voice use. Videostroboscopy, electromyography, voice analysis, and electroglottography can provide crucial information on the function of the EBSLN following neck surgery.

Electrical stimulation-based nerve location prediction for cranial nerve VII localization in acoustic neuroma surgery.

INTRODUCTION: Cranial nerve (CN) VII localization is a critical step during acoustic neuroma surgery because the nerve is generally hidden due to the tumor mass. The patient can suffer from Bell's palsy if the nerve is accidentally damaged during tumor removal. Surgeons localize CN VII by exploring the target area with a stimulus probe. Compound muscle action potentials (CMAPs) are elicited when the probe locates the nerve. However, false positives and false negatives are possible due to unpredictable tissue impedance in the operative area. Moreover, a single CMAP amplitude is not correlated with probe-to-nerve distance. OBJECTIVES: This paper presents a new modality for nerve localization. The probe-to-nerve distance is predicted by the proposed nerve location prediction model. METHODS: Input features are extracted from CMAP responses, tissue impedance, and stimulus current. The tissue impedance is calculated from the estimated resistance and capacitance of the tissue equivalent circuit. In this study, experiments were conducted in animals. A frog's sciatic nerve and gastrocnemius were used to represent CN VII and facial muscle in humans, respectively. Gelatin (2.8%) was used as a mock material to mimic an acoustic neuroma. The %NaCl applied to the mock material was used to emulate uncontrollable impedance of tissue in the operative area. RESULTS: The 10-fold cross-validation results revealed an average prediction accuracy of 86.71% and an average predicted error of 0.76 mm compared with the measurement data. CONCLUSION: The proposed nerve location prediction model could predict the probe-to-nerve distance across various impedances of the mock material.

Curative-like analgesia in a neuropathic pain model: parametric analysis of the dose and the duration of treatment with a high-efficacy 5-HT(1A) receptor agonist.

High-efficacy activation of central 5-HT(1A) receptors by means of the recently discovered, selective 5-HT(1A) receptor ligand, F 13640 [(3-chloro-4-fluoro-phenyl)-[4-fluoro-4-{[(5-methyl-pyridin-2-ylmethyl)-amino]methyl}piperidin-1-yl]methanone, fumaric acid salt] causes an unprecedented, broad-spectrum analgesia in rat models of acute and chronic pain of nociceptive and neuropathic origin; it also is effective in conditions where opioids either are ineffective, induce analgesic tolerance, or elicit persistent hyperalgesia/allodynia. Inversely mirroring morphine's actions, F 13640's ("curative-like") analgesic effects persist after the discontinuation of treatment. Here, we examined the relationships, if any, between the dose and the duration of F 13640 treatment on the one hand, and the duration of persistent analgesia on the other. Rats received unilateral infraorbital nerve injury and developed allodynia - as assessed by an increased response to von Frey filament stimulation - within 24 days; thereafter, using osmotic pumps, rats were subcutaneously infused with F 13640 in two experiments. In one, a one-week infusion was instituted at 0.04-10-mg/day doses; in a second experiment, a 0.63-mg/day dose was implemented for a duration ranging from 1 to 56 days. These 250- and 56-fold variations of the dose and duration of treatment caused post-treatment, persistent analgesia for about 10 and 40 days, respectively. At least as much as dose, the duration of F 13640 treatment determines F 13640-induced persistent analgesia. Neuroadaptive modulations at pre- and postsynaptic, brain and spinal cord 5-HT(1A) receptors may be involved in the dynamical, dose- and time-dependent, pre-treatment rise and post-treatment decay of the analgesia induced by high-efficacy 5-HT(1A) receptor activation.

Clinical and Electromyographic Characteristics of Unilateral Vocal Fold Paralysis With Lower Cranial Nerve Injury.

OBJECTIVES: The aim was to investigate the clinical and electromyographic characteristics of patients with unilateral vocal fold paralysis (UVFP) combined with lower cranial nerve injury. STUDY DESIGN: This is a case series with chart review. METHODS: Among 368 patients with idiopathic UVFP, 31 patients (8.4%) were eventually diagnosed with lower cranial nerve palsy after examinations of the head and neck, radiology, and electromyogram (EMG). The clinical and electromyographic characteristics of these patients were analyzed. RESULTS: Of the 31 patients, 27 patients exhibited obvious abnormal lower cranial nerve injury physical signs, and 4 patients showed atypical physical signs, identified by EMG. Ultimately, 41.9% (13/31) were diagnosed with idiopathic causes, 38.7% (12/31) with intracranial or skull-base lesions on radiology, 12.9% (4/31) with lower cranial neuritis, and 6.4% (2/31) with radiation-induced lower cranial nerve palsy. Among the cranial lesions, lesions of the jugular foramen region were the most common (50%, 6/12). All 26 patients who underwent EMG tests were confirmed to have vagus nerve impairments (11 complete and 15 incomplete) and accessory nerve impairments (16 complete and 10 incomplete), whereas only 13 patients (50%) exhibited hypoglossal nerve injuries (5 complete and 8 incomplete). CONCLUSIONS: For patients with clinically "idiopathic" UVFP, physical examinations of the lower cranial nerves are essential screening procedures. For patients with abnormal or suspicious physical signs, radiology should be performed to detect possible cranial or cervical lesions. EMG tests were strongly recommended to identify suspicious lower cranial nerve injury and its severity, and may help to predict the prognosis.

Functional Recovery of Cranial Nerves in Patients with Traumatic Orbital Apex Syndrome.

OBJECTIVE: Traumatic orbital apex syndrome (TOAS) is a rare disease characterized by the damage of cranial nerves (CNs) II, III, IV, and VI. The aim of our study was to analyze the functional recovery of CNs in TOAS and discuss the management of these patients. METHODS: We retrospectively reviewed 28 patients with TOAS treated in the Department of Neurosurgery, Shanghai Changzheng Hospital from February 2006 to February 2016. Functional recovery of CNs was evaluated based on extraocular muscle movement and visual perception. Follow-up duration was at least 6 months. RESULTS: There were 26 males and 2 females with a mean age of 35.3 years. The most common cause of TOAS was traffic accident. CN IV suffered the lightest injury among CNs III, IV, and VI. CN II achieved obvious improvement at 3-month follow-up, while other CNs enjoyed evident improvement at 6-month follow-up. There was no significant difference between conservative treatment and surgical decompression. CONCLUSION: CNs passing through orbital apex region might recover to different degrees several months after proper management. Clinical decision should be individualized and surgical decompression could be considered with evidence of fracture, hematoma, or deformation.

Cerebellopontine angle lipoma with extracranial extension.

Lipomas of the cerebellopontine angle (CPA) are rare. A recent literature review identified only 98 reported cases of CPA lipoma. We present here a case of CPA lipoma in a 28-year-old woman who was admitted to our hospital with hearing loss in her left ear. Computed tomography scan and magnetic resonance imaging revealed a CPA mass lesion with extracranial extension around the left internal carotiol artery. The patient was operated on in the sitting position via a right suboccipital craniectomy. The intracranial part of the mass was partially removed. Histopathological examination resulted in a diagnosis of lipoma. Surgical treatment of CPA lipomas is rarely indicated, and the aim of surgery must be decompression of neural structures.