Cranial Nerve Motor Research Articles

CNSC-06. NAVIGATING BRAIN CANCER: PATIENT STORIES AND MEDICAL BREAKTHROUGH

Abstract The complex interplay of genetic mutation, dys regulated signalling pathways, Epigenetic modifications and Interaction with tumor microenvironment are the major aggravating factors for Brain Tumors. Neurological complications involve Increased Intracranial pressure, Seizures, Motor and Sensory deficits, Aphasia, Hydrocephaly, Behavioral and personality changes, Cerebellar Symptoms. It is diagnosed in a sequential steps. Collecting good history from patient in primary then examining the patient all through and making some investigations to come to a final diagnosis. On asking history to a patient he complains of recurrent convulsions, Personality changes and some motor activity deficit and loss of few senses. On examination we can reveal defect in cranial nerve functions, Motor or sensory deficits, loss of reflexes and coordination. Then Investigations being the next step for diagnosis, We ask the patient to undergo for a test for Blood Biomarkers and CSF analysis in case of suspection of metastatic Brain tumors. Biopsy to obtain for Histopathological Examination. Histopathological examination is done for analysis of genetic mutations and molecular markers. The other imaging techniques like MRI, MRS, CT, PET, EEG are done. This gives a clear picture of what actually caused tumor and shows a way for treatment. Now the treatment involves both Medical and Surgical treatment. Medical treatment includes Chemotherapy along with radiation therapy where the drugs given are Temozolomide and targeted therapy included EGFR BRAF inhibitors for glioblastoma and low grade gliomas respectively. Tumor treating fields- Optune is given. Surgical treatment involves Craniotomy for removal of primary Brain tumors, Neuro Endoscopy if tumor is present in ventricles or base of Brain, Laser interstitial Thermal therapy for deap seated and recurrent brain tumors. This is all about the treatment and now the patient management is very important for further clinical help. Physical, occupational and speech therapy helps patients recover. Symptomatic approach for inoperable tumors Provide comprehensive support for patients nearing end of life, Emphasise confidence and Quality of life.

COVID-19 Vaccination and Ocular Adverse Events: A Self-Controlled Case Series Study From the Entire South Korean Population

This study aimed to assess the risk of ocular adverse events, including retinal artery occlusion (RAO), retinal vein occlusion (RVO), noninfectious uveitis (NIU), noninfectious scleritis (NIS), optic neuritis (ON), ischemic optic neuropathy (ION), and ocular motor cranial nerve palsy (OMCNP), following Coronavirus Disease 2019 (COVID-19) vaccination. Population-based self-controlled case series METHODS: This study utilized nationwide claims and vaccination data provided by the Korea National Health Insurance Service and Korea Disease Control and Prevention Agency. From the entire South Korean population of 52 million individuals, patients with incident RAO, RVO, anterior NIU, nonanterior NIU, NIS, ON, ION, or OMCNP between January 2021 and March 2022 were included. The postvaccination risk period was defined as up to 56 days after COVID-19 vaccination. The relative incidence rate ratios (IRRs) for RAO, RVO, anterior NIU, nonanterior NIU, NIS, ON, ION, and OMCNP during the risk periods were measured using conditional Poisson regression. The study included 6,590, 70,120, 137,958, 17,921, 15,492, 2,039, 49,089, and 11,312 cases of incident RAO, RVO, anterior NIU, nonanterior NIU, NIS, ON, ION, and OMCNP, respectively. The IRRs (95% confidence interval) during the early risk period (0-28 days) were 0.95 (0.88-1.01), 0.96 (0.94-0.98), 0.93 (0.91-0.94), 0.93 (0.89-0.96), 0.96 (0.92-1.01), 1.04 (0.92-1.18), 0.98 (0.95-1.00), and 0.91 (0.86-0.96), respectively. In the late risk period (29-56 days), the IRRs were 0.96 (0.89-1.03), 0.93 (0.91-0.96), 0.96 (0.95-0.98), 1.00 (0.95-1.04), 0.96 (0.91-1.01), 1.00 (0.87-1.15), 1.01 (0.98-1.04), and 0.95 (0.90-1.01), respectively. COVID-19 vaccination did not increase the risk of incident RAO, RVO, anterior NIU, nonanterior NIU, NIS, ON, ION, or OMCNP during the postvaccination period.

Neurosyphilis patients presenting with ocular motor cranial nerve palsy in the modern antibiotic era: Case series from two centers and review of the literature

BackgroundSyphilis can mimic the clinical features of many neurological disorders and cause ocular motor cranial nerve palsy (OMCNP). This study aims to characterize the clinical features of neurosyphilis patients presenting with OMCNP. Methods In a retrospective study and literature review, demographic data, clinical presentations, laboratory findings, radiological findings, treatment approaches, and outcomes were recorded and analyzed. ResultsOverall, 0.74 % and 1.64 % of patients presenting to two institutes exhibited syphilitic OMCNP, respectively. A total of 32 patients (23 from the literature) were recruited, with a median age of 46 years and a predominance of males (81.3 %). Meningovascular neurosyphilis was diagnosed in 29 patients (90.6 %), and tabes dorsalis was found in 3 patients (9.4 %). Unilateral OMCNP was present in 24 patients (65.5 %). Unilateral sixth nerve palsy was observed in 10 patients (34.5 %), followed by unilateral third nerve palsy in 9 patients (31.0 %), and unilateral multiple OMCNP in 5 patients (17.2 %). A total of 12 patients (41.4 %) presented with isolated OMCNP, and 4 of these individuals developed other neurological deficits during the disease. Pupillary involvement was found in all patients who presented unilateral third nerve palsies. After treatment, 17 patients (58.6 %) achieved complete recovery of ocular motility; 6 patients (20.7 %) achieved partial recovery; 5 patients (17.2 %) remained stable; and 1 patient (3.5 %) became progressive. ConclusionsPatients presenting with OMCNP alone or combined with other cranial nerve deficits should be screened for neurosyphilis, and the standard treatment regimen should be initiated if a diagnosis of neurosyphilis is established.

Atypical presentations in an RTD patient and report of novel SLC52A3 and SLC52A2 mutations.

Riboflavin Transporter Deficiency (RTD) is a rare neurological disorder characterized by pontobulbar palsy, hearing loss, and motor cranial nerve involvement. SLC52A3 and SLC52A2 mutations are causes of RTD. SLC52A2 mutations are usually found in childhood onset cases. Fifteen Iranian RTD diagnosed patients without SLC52A2 mutations have been previously described. We aimed to identify causative mutations in two childhood cases. We recruited patients with diagnosis of BVVL. Comprehensive clinical evaluations were performed on the patients. SLC52A3 and SLC52A2 genes were PCR-amplified and Sanger sequenced. Candidate disease causing variations were screened for segregation with disease status in the respective families and control individuals. A novel homozygous SLC52A3 mutation (p.Met1Val) and a heterozygous SLC52A2 mutation (p.Ala288Val) were both observed in one proband with typical RTD presentations. The aggregate of presentations in the early stages of disease in the second patient that included weakness in the lower extremities, absence of bulbar or hearing defects, prominent sensory polyneuropathy as evidenced in electrodiagnostic studies, and absence of sensory symptoms including sensory ataxia did not prompt immediate RTD diagnosis. Dysarthria and decreased hearing manifested later in the disease course. A novel homozygous SLC52A2 (p.Val314Met) mutation was identified. A literature search found recent reports of other atypical RTD presentations. These include MRI findings, speech understanding difficulties accompanied by normal hearing, anemia, and left ventricular non-compaction. Knowledge of unusual presentations lessens the chance of misdiagnosis or delayed RTD diagnosis which, in light of favorable effects of riboflavin supplementation, is of immense importance.

Age-Related Risk of Stroke Following Ocular Motor Cranial Nerve Palsy.

This cohort study aims to examine the relationship between the occurrence of cranial nerve palsy (CNP) affecting the third, fourth, or sixth cranial nerve and the subsequent risk of stroke, with a particular focus on the modulating effect of age on this association. We established a cohort of individuals diagnosed with third, fourth, or sixth CNP who underwent national health screening within 2 years of diagnosis from 2010 to 2017. A control group was matched by sex and age at a ratio of 1:5. Participants were followed until December 31, 2019. We use multivariable Cox proportional hazards regression analyses to assess the association between ocular motor CNP and subsequent stroke stratified by age. Covariates including lifestyle, health behavior, underlying comorbidities, and Charlson comorbidity index score were also adjusted. Compared with the control group, the ocular motor CNP group had a higher risk of stroke after adjusting for potential confounders (hazard ratio [HR], 1.23 [95% CI,, 1.08-1.39]). The risk of stroke increased by 8.91 times in individuals with ocular motor CNP who were in their 30s (HR, 8.91 [95% CI, 1.63-48.66]). The risk increased by 2.49 times in those who were in their 40s, 1.78 times in those who were in their 50s, and 1.32 times in those who were in their 60s (HRs, 2.49, 1.78, and 1.32 [95% CI, 1.39-4.45, 1.31-2.42, and 1.08-1.62], respectively). However, for those who were in their 20s, 70s, or 80s, the incidence of stroke did not significantly increase. Our study establishes an association between ocular motor CNP and an increased risk of stroke, particularly in young adults.

Proteinuria and risk of ocular motor cranial nerve palsy: a nationwide population-based study

Understanding the association between dipstick-detected proteinuria and oculomotor cranial nerve palsy (CNP) could have significant implications for understanding the mechanism of CNP development and for developing preventive strategies against CNP development in patients with proteinuria. This study aimed to determine the relationship between dipstick-determined proteinuria and ocular motor CNP using National Sample Cohort (NSC) database from Korea’s National Health Insurance Service (NHIS). A nationwide population-based cohort study was conducted using data from the NSC database of Korea’s NHIS. These data were collected from 2009 to 2018. A one-year time lag was established to prevent a situation in which the causal link was inverted. Participants aged 20 years or more who were diagnosed with proteinuria in 2009 were included. Individuals with specific pre-existing CNP, missing data, and those who were newly diagnosed with CNP or who died within one year of being tested were excluded. The study population was classified into six groups according to the degree of proteinuria (negative, trace, or between 1 + and 4 +) based on the urine dipstick test. A Cox proportional hazard regression analysis was performed to determine the linkage between the degree of proteinuria and ocular motor CNP. A total of 5,807 (0.14% of subjects) with ocular motor CNP were assigned to the ocular motor CNP group and 4,047,205 subjects were assigned to the control group. After full adjustment of comorbidities, hazard ratios (HRs) for 1 + , 2 + , 3 + and 4 + proteinuria groups were 1.449 (95% confidence interval [CI] 1.244–1.687), 2.081 (1.707–2.538), 1.96 (1.322–2.904), and 3.011 (1.507–6.014), respectively, for developing ocular motor CNP compared to the proteinuria-negative group. In subgroup analysis, the HR of patients with proteinuria for the development of ocular motor CNP was higher in the younger age group (less than 40 years) (P = 0.0242) and the group with DM (P = 0.04). Our population-based cohort study demonstrated a significant association between proteinuria and the incidence of CNP, suggesting that urine protein level could be a new clinical marker for predicting the development of CNP.

Radiological features of patients with headache as a presenting symptom of neurosarcoidosis.

To describe the radiological features of patients with headache as a presenting symptom of neurosarcoidosis. Neurologic complications occur in approximately 5%-10% of patients with sarcoidosis, and approximately 50% of these patients have neurologic deficits at the time sarcoidosis is first diagnosed. A wide spectrum of central and peripheral nervous system clinical manifestations may be observed, including cranial nerve palsies, sensory and/or motor deficits, and headache. Magnetic resonance imaging (MRI) results in patients with neurosarcoidosis may include abnormal contrast enhancement, structural masses, and demyelinating lesions. This single-center retrospective cohort study assessed patients who were diagnosed with neurosarcoidosis in an urban tertiary care center between 1995 and 2016. We included patients who had MRI results at the time of diagnosis. Patients were divided into two groups based on the presence or absence of headache as a presenting symptom. The MRI result of meningeal contrast enhancement was reviewed. Of the 110 patients analyzed, 30 (27.3%) had an initial presenting symptom of headache while 80 (72.7%) did not. Patients with headache had a higher proportion of meningeal contrast enhancement on MRI (66.7% [20/30] vs. 25.0% [20/80]; p < 0.001) and leptomeningeal involvement (53.3% [16/30] vs. 7.5% [6/80], p < 0.001) compared to patients with no headache. However, those with headache had a lower proportion of spinal cord localization (13.8% [4/29] vs. 34.2% [26/76], p = 0.038) and intraparenchymal central nervous system involvement (16.7% [5/30] vs. 51.3% [41/80], p = 0.001) compared to patients with no headache. Patients with neurosarcoidosis who presented with headache as an initial symptom had a higher proportion of meningeal contrast enhancement seen by MRI than patients who presented with other neurological symptoms. This suggests a clinico-radiologic link between headache and meningeal disruption in patients with neurosarcoidosis.

An in vitro model for postoperative cranial nerve dysfunction and a proposed method of rehabilitation with N-acetylcysteine microparticles

PurposeWhen operating near cranial motor nerves, transient postoperative weakness of target muscles lasting weeks to months is often observed. As nerves are typically intact at a procedure’s completion, paresis is hypothesized to result from a combination of neurapraxia and axonotmesis. As both neurapraxia and axonotmesis involve Schwann cell injury and require remyelination, we developed an in vitro RSC96 Schwann cell model of injury using hydrogen peroxide (H2O2) to induce oxidative stress and investigated the efficacy of candidate therapeutic agents to promote RSC96 viability. As a first step in developing a long-term local administration strategy, the most promising of these agents was incorporated into sustained-release microparticles and investigated for bioactivity using this assay.MethodsThe concentration of H2O2 which reduced viability by 50% was determined to establish a standard for inducing oxidative stress in RSC96 cultures. Fresh cultures were then co-dosed with H2O2 and the potential therapeutics melatonin, N-acetylcysteine, resveratrol, and 4-aminopyridine. Schwann cell viability was evaluated and the most efficacious agent, N-acetylcysteine, was encapsulated into microparticles. Eluted samples of N-acetylcysteine from microparticles was evaluated for retained bioactivity.Results100 µM N-acetylcysteine improved the viability of Schwann cells dosed with H2O2. 100 µM Microparticle-eluted N-acetylcysteine also enhanced Schwann cell viability.ConclusionWe developed a Schwann cell culture model of iatrogenic nerve injury and used this to identify N-acetylcysteine as an agent to promote recovery. N-acetylcysteine was packaged into microparticles and demonstrated promise as a locally administrable agent to reduce oxidative stress in Schwann cells.

Herpes zoster in neuro-ophthalmology: a practical approach.

Herpes Zoster (HZ) or shingles is the reactivation of the Varicella Zoster Virus (VZV), usually along a single sensory nerve, but can affect both sensory and motor cranial nerves. Major risk factors for HZ include immunosuppressed status and age older than 60 years. In the United States, the lifetime risk of HZ is approximately 30%. Worldwide, the median incidence of HZ is 4-4.5 per 1000 person-years across the Americas, Eurasia, and Australia. HZ ophthalmicus, occurring in 10-20% of patients, is an ophthalmic emergency characterized by VZV reactivation along the V1 branch of the trigeminal nerve. Approximately half of this patient subgroup will go on to develop ocular manifestations, requiring prompt diagnosis and management. While anterior segment complications are more common, neuro-ophthalmic manifestations are rarer and can also occur outside the context of overt HZ ophthalmicus. Neuro-ophthalmic manifestations include optic neuropathy, acute retinal necrosis or progressive outer retinal necrosis, cranial neuropathy (isolated or multiple), orbitopathy, and CNS manifestations. Although typically a clinical diagnosis, diagnosis may be aided by neuroimaging and laboratory (e.g., PCR and serology) studies. Early antiviral therapy is indicated as soon as a presumptive diagnosis of VZV is made and the role of corticosteroids remains debated. Generally, there is wide variation of prognosis with neuro-ophthalmic involvement. Vaccine-mediated prevention is recommended. In this review, we summarize neuro-ophthalmic manifestations of VZV.

AI-assisted automatic MRI-based tongue volume evaluation in motor neuron disease (MND)

PurposeMotor neuron disease (MND) causes damage to the upper and lower motor neurons including the motor cranial nerves, the latter resulting in bulbar involvement with atrophy of the tongue muscle. To measure tongue atrophy, an operator independent automatic segmentation of the tongue is crucial. The aim of this study was to apply convolutional neural network (CNN) to MRI data in order to determine the volume of the tongue.MethodsA single triplanar CNN of U-Net architecture trained on axial, coronal, and sagittal planes was used for the segmentation of the tongue in MRI scans of the head. The 3D volumes were processed slice-wise across the three orientations and the predictions were merged using different voting strategies. This approach was developed using MRI datasets from 20 patients with ‘classical’ spinal amyotrophic lateral sclerosis (ALS) and 20 healthy controls and, in a pilot study, applied to the tongue volume quantification to 19 controls and 19 ALS patients with the variant progressive bulbar palsy (PBP).ResultsConsensus models with softmax averaging and majority voting achieved highest segmentation accuracy and outperformed predictions on single orientations and consensus models with union and unanimous voting. At the group level, reduction in tongue volume was not observed in classical spinal ALS, but was significant in the PBP group, as compared to controls.ConclusionUtilizing single U-Net trained on three orthogonal orientations with consequent merging of respective orientations in an optimized consensus model reduces the number of erroneous detections and improves the segmentation of the tongue. The CNN-based automatic segmentation allows for accurate quantification of the tongue volumes in all subjects. The application to the ALS variant PBP showed significant reduction of the tongue volume in these patients and opens the way for unbiased future longitudinal studies in diseases affecting tongue volume.

The Etiology of Paralytic Strabismus at an Indonesian Tertiary Hospital from 2017 to 2022

Highlights: 1. This study investigated the etiology of paralytic strabismus, a condition that requires further research to prevent its incidence, particularly in adults.2. The findings of this study provided valuable insight into the primary etiology of paralytic strabismus and its underlying factors. Abstract Paralytic strabismus is the most common cause of adult-onset strabismus. It can result from paralysis of the third, fourth, or sixth cranial nerves, either separately or in combination, which are responsible for innervating the ocular motor muscles. Paralysis of these cranial nerves occurs due to congenital disorders, neoplasms, trauma, intracranial processes, idiopathic diseases, and other causes. This study aimed to determine the etiology of paralytic strabismus incidence at the Department of Ophthalmology of Dr. Soetomo General Academic Hospital, Surabaya, Indonesia, between 2017 and 2022. This study employed a retrospective methodology and utilized total sampling. The medical records of patients diagnosed with paralytic strabismus were used to collect secondary data. Out of the total of 282 cases, the most common condition was combined ocular motor cranial nerve palsy, which accounted for 102 (36.2%) cases. The main factors contributing to this condition were neoplasms (37.2%), intracranial processes (25.5%), trauma (25.5%), other causes (8.8%), idiopathic diseases (2%), and congenital disorders (1%). The incidence of third cranial nerve palsy and sixth cranial nerve palsy was equally prevalent, each accounting for 86 (30.5%) cases. Meanwhile, fourth cranial nerve palsy was the least frequent with just eight (2.8%) cases. This study concluded that the most frequent etiology of paralytic strabismus was combined ocular motor nerve paralysis, which primarily results from neoplasms.

Abducens Nerve Duplication: Novel Intraoperative and Radiographic Observation of a Rare Anatomical Variant

Abstract Objectives The abducens nerve has a long, serpentine subarachnoid course with complex topographical relationships, rendering abducens nerve palsy the most common ocular motor cranial nerve palsy in adults and second most common in pediatric patients, with anatomical variants reported in the literature. Preoperative awareness of abducens nerve variant anatomy may help prevent inadvertent intraoperative injury. Design This study is a case report with a review of the abducens nerve anatomy and variants. Setting The study setting included outpatient, inpatient, and operating room in the neurosurgery department of a quaternary referral center. Participants The study included a woman in her early 30s with a diagnosis of petrous meningioma. Main Outcome Measures In vivo documentation of a type 3 abducens nerve duplication was carried out. Results A left extended retrosigmoid craniotomy was recommended for the petroclival meningioma resection. Intraoperatively, a complete duplication of the left abducens cisternal segment was encountered and photographed. The left unilateral abducens nerve duplication was confirmed with postoperative volumetric magnetic resonance imaging using the FIESTA (fast imaging employing steady-state acquisition) sequence, revealing the union of the duplicated cisternal abducens nerves into a single trunk from Dorello's canal distally. Conclusions Abducens nerve variants are uncommon, and although reported in the setting of cadaveric dissection, in vivo documentation of them is limited. This case report of an in vivo type 3 abducens nerve duplication with intraoperative photographic and radiographic images highlights the need for clinical awareness to avoid inadvertent intraoperative injury.

Correlation between clinical-laboratory profile and outcome of AES cases in children: A hospital-based study

Objective: This study aims to determine the correlation between clinical as well as laboratory profile changes with the outcome of acute encephalitis syndrome (AES) cases. Materials and Methods: This prospective observational study was conducted in the Department of Pediatrics at Jorhat Medical College and Hospital, Assam over a period of 1 year where 49 diagnosed cases of AES in children aged between 1 month and 12 years were enrolled. Results: The study found that fever (100%) and altered sensorium (100%) were the most common clinical presentations in AES cases, followed by seizure (63%), headache (34.7%), vomiting (26.5%), diarrhea (22.4%), etc. Japanese encephalitis (JE) was the most common cause of AES (28.6%), followed by herpes simplex virus (4.1%), pyogenic meningitis (4.1%), and tubercular meningitis (2%), etc. However, the majority of cases (61.2%) were found to have an unknown etiology. Among the 49 cases, 27 (55.1%) recovered without neurological sequelae, 8 (16.8%) had neurological sequelae, and 14 (28.6%) died during the course of treatment. The most common neurological sequelae observed were motor deficit (37.5%), behavioral disorders, aphasia (25% each), and cranial nerve palsy. Glasgow coma scale (GCS) at the time of admission and during the time of hospital stay was found to have a significant (p&lt;0.05) correlation with outcome in AES patients. Conclusion: The study concludes that AES cases commonly present with fever, altered sensorium, seizure, headache, vomiting, and signs of meningeal irritation. JE remains a major known cause of AES in children in this region of India. GCS at the time of admission and during the time of hospital stay were found to have a significant correlation with outcome. The neurological sequelae highlight the need for global attention to combat them save the lives of children.

Ocular Motor Cranial Nerve Palsies and Increased Risk of Primary Malignant Brain Tumors: South Korean National Health Insurance Data.

The aim of this study was to investigate the association between ocular motor cranial nerve palsies (OMCNP) and the occurrence of primary malignant brain tumors in a Korean population, using the national sample cohort database from Korea National Health Insurance Service (KNHIS). KNHIS data between 2010 and 2017 were analyzed. Our sample encompassed 118,686 participants, including 19,781 from a recently diagnosed OMCNP cohort and 98,905 from a matched control cohort through a 1:5 propensity score matching based on age and gender. To counteract the issue of reverse causation, we integrated a one-year time lag in our sensitivity analysis. Study participants were followed up until 31 December 2019. Cox proportional hazard regression analysis was used to compute the adjusted hazard ratio (HR) for primary malignant brain tumors according to the OMCNP diagnosis. Additionally, we performed a subgroup analysis to discern effects of various factors on the association between OMCNP and primary malignant brain tumors. HR for primary malignant brain tumors was 3.272 (95% confidence interval [CI]: 2.294 to 4.665) in the OMCNP cohort compared to the control cohort in a fully adjusted model for age, sex, socio-economic status, smoking, drinking, regular physical exercise, hypertension, diabetes, dyslipidemia, obesity, chronic kidney disease, and human immunodeficiency virus infection. Further subgroup analysis revealed that the risk of primary malignant brain tumors was significantly increased in women with OMCNP compared to men with OMCNP (HR: 5.118 in women vs. 2.441 in men, p = 0.0440), and in those aged <65 years than in those aged ≥65 years (HR: 6.951 in age < 65 years vs. 1.899 in age ≥ 65 years, p = 0.0006). Our population-based cohort study demonstrated a significantly increased risk of subsequent primary malignant brain tumors in patients with OMCNP. Particularly, OMCNP-afflicted women aged below 65 manifested a heightened probability of developing primary malignant brain tumors compared to those devoid of OMCNP.

Study of etiological profile of patients with paralytic strabismus in a tertiary care hospital in India: a cross-sectional study

Abstract Introduction: Paralytic strabismus, a type of strabismus caused by paralysis of one or more extraocular muscles, can lead to a variety of ocular and psychosocial sequelae. Etiology varies in different types of paralytic strabismus. Numerous studies have shown that ocular motor cranial nerve palsies have a variety of causes including vascular disease, head trauma, intracranial tumour or aneurysm and inflammatory disorders.Materials and Methods: A cross-sectional study was conducted at a tertiary eye hospital to evaluate Paralytic squint by Neuroimaging in patients presenting to the Squint department of Sarojini Devi Eye Hospital Hyderabad from June 2021 to May 2022. Paralytic strabismus cases with limitation of ocular motility were enrolled and a detailed examination was performed to know the etiology. Results: 190 patients (1.35%) were diagnosed with paralytic strabismus. Ischemia constituted to be the major cause of paralytic strabismus i.e. (42.1%) followed by trauma (20%). The 3rd cranial nerve was the most commonly involved (34.73%), followed by the 6th cranial nerve (32.63%). Multiple cranial nerves were involved in 20% of cases. The 3rd CN was involved, primarily due to ischemia in both males and females while the 6th CN was affected with trauma, neoplasm, and ischemia being prominent causes. Conclusion: The study showed that ischemia, trauma and idiopathy are some of the major etiologies of paralytic strabismus with male predominance. The cranial nerve involvement also varied with the etiology of paralytic strabismus.

The pre-Bötzinger complex is necessary for the expression of inspiratory and post-inspiratory motor discharge of the vagus

The mammalian three-phase respiratory motor pattern of inspiration, post-inspiration and expiration is expressed in spinal and cranial motor nerve discharge and is generated by a distributed ponto-medullary respiratory pattern generating network. Respiratory motor pattern generation depends on a rhythmogenic kernel located within the pre-Bötzinger complex (pre-BötC). In the present study, we tested the effect of unilateral and bilateral inactivation of the pre-BötC after local microinjection of the GABAA receptor agonist isoguvacine (10 mM, 50 nl) on phrenic (PNA), hypoglossal (HNA) and vagal nerve (VNA) respiratory motor activities in an in situ perfused brainstem preparation of rats. Bilateral inactivation of the pre-BötC triggered cessation of phrenic (PNA), hypoglossal (HNA) and vagal (VNA) nerve activities for 15–20 min. Ipsilateral isoguvacine injections into the pre-BötC triggered transient (6–8 min) cessation of inspiratory and post-inspiratory VNA (p < 0.001) and suppressed inspiratory HNA by − 70 ± 15% (p < 0.01), while inspiratory PNA burst frequency increased by 46 ± 30% (p < 0.01). Taken together, these observations confirm the role of the pre-BötC as the rhythmogenic kernel of the mammalian respiratory network in situ and highlight a significant role for the pre-BötC in the transmission of vagal inspiratory and post-inspiratory pre-motor drive to the nucleus ambiguus.

Anterolateral upper cervical approach for ventral C1-C2 meningioma.

The surgical management of ventral upper cervical meningiomas poses significant challenges due to their deep location and limited accessibility. These tumors have the potential to compress or involve nearby neurovascular structures, leading to various neurological complications including inferior cranial nerve palsy, motor deficits, and sensory disturbances such as hypoesthesia, paresthesia, and impaired coordination. To address this issue, surgical intervention through an anterolateral or far lateral approach has been recognized as the optimal treatment strategy. In this video, the authors present a detailed demonstration of the operative technique using an anterolateral upper cervical approach to safely resect a ventrally located C1-2 meningioma.

P11.48.A STEREOTACTIC RADIOSURGERY FOR EPENDYMOMA IN PEDIATRIC AND ADULT PATIENTS: A SINGLE-INSTITUTION EXPERIENCE

Abstract BACKGROUND Ependymoma is typically classified as WHO grade 2 and its anaplastic variant as grade 3. Despite standard treatment approaches, incomplete resection or anaplastic features can lead to poor prognosis. Stereotactic radiosurgery (SRS) is a promising minimally invasive option for recurrent ependymomas after surgery and radiation therapy. This study aims to evaluate the efficacy and safety of CyberKnife radiosurgery in treatment of WHO grade II versus III ependymomas in both pediatric and adult populations. MATERIAL AND METHODS In our study, we evaluated the clinical and radiological records of patients who underwent CyberKnife SRS for ependymoma at our institution between 1998 and 2023. The follow-up data were available for a total of 75 ependymomas in 34 patients. The study population consisted of 14 pediatric patients (ages 3-18) and 20 adult patients (ages 19-75). The median age was 21 years and the median tumor volume accounted for 0.64 cc. The median biologically equivalent dose (BED) and single-fraction equivalent dose (SFED) were 108 Gy and 16.6 Gy, respectively. The SRS was administered at the 77% of the median isodose line. RESULTS At a median follow-up of 42.7 months (range: 3.8-438.3) after treatment, our analysis revealed that only 17 (22.7%) ependymomas progressed. The 5-year local tumor control (5-yrs-LTC) rate for all ependymomas was 78.1%, with a lower rate of 59.6% observed in the pediatric cohort and a higher rate of 90.2% in adult patients. For ependymomas classified as WHO grade II, the 5-yrs-LTC rate was 85.9%, whereas it was 58.5% for those classified as WHO grade III. The 5-year overall survival (5-yrs-OS) rate was 73.6% for all patients, with significantly higher rates observed in pediatric patients (94.7%) than in adult patients (41%). The 5-yrs-OS rate was 100% for patients with WHO grade II tumors, whereas it decreased significantly to 35.9% for patients with WHO grade III ependymomas. The 5-year progression-free survival (5-yrs-PFS) rate was 68.5% for all patients, with higher rates observed in pediatric patients (78.3%) than in adult patients (49.2%). The 5-yrs-PFS rate for patients with WHO grade II lesions was 88.8%, whereas it was significantly lower at 32.6% for patients with WHO grade III tumors. Stereotactic radiosurgery (SRS) was effective in improving tumor-associated symptoms in 29 (85.3%) patients with 62 (82.7%) symptomatic ependymomas. These symptoms included headache, back pain, dizziness, nausea, vomiting, cranial nerve palsy, ataxia, motor impairment, sensory deficit, seizures, and weight loss. Notably, no patients developed adverse radiation effects. CONCLUSION CyberKnife SRS is a safe and effective treatment for ependymoma in both adults and children, with potential for significant improvements in tumor-related symptoms. Our study supports its use as a minimally invasive alternative to surgery, warranting further investigation.

Dynamic Changes in Metabolic Status Are Associated With Risk of Ocular Motor Cranial Nerve Palsies.

To investigate whether recovery from or development of metabolic syndrome (MetS) in a population is associated with an altered risk for ocular motor cranial nerve palsy (CNP). This cohort study included 4,233,273 adults without a history of ocular motor cranial nerve palsy (ocular motor CNP) who underwent 2 consecutive biennial health screenings provided by the Korean National Health Insurance System between 2009 and 2011. They were followed up until December 31, 2018. Participants were categorized into a MetS-free, MetS-developed, MetS-recovered, or MetS-chronic group. A multivariable Cox proportional hazard regression model was used. Model 3 was adjusted for age, sex, smoking status, alcohol consumption, and physical activity. Compared with the MetS-free group, the MetS-chronic group had the highest risk of ocular motor CNP (hazard ratio [HR]: 1.424; 95% confidential interval [CI]: 1.294-1.567, Model 3), followed by the MetS-developed group (HR: 1.198, 95% CI: 1.069-1.343), and the MetS-recovered group (HR: 1.168, 95% CI: 1.026-1.311) after adjusting for potential confounders. The hazard ratio of ocular motor CNP in men with chronic MetS was 1.566 (95% CI, 1.394-1.761) while that of women with chronic MetS was 1.191 (95% CI, 1.005-1.411). Among age groups, those in their 30s and 40s showed the highest association between dynamic MetS status and ocular motor CNP. In our study, recovering from MetS was associated with a reduced risk of ocular motor CNP compared with chronic MetS, suggesting that ocular motor CNP risk could be managed by changing MetS status.

Axonal mapping of the motor cranial nerves.

Basic behaviors, such as swallowing, speech, and emotional expressions are the result of a highly coordinated interplay between multiple muscles of the head. Control mechanisms of such highly tuned movements remain poorly understood. Here, we investigated the neural components responsible for motor control of the facial, masticatory, and tongue muscles in humans using specific molecular markers (ChAT, MBP, NF, TH). Our findings showed that a higher number of motor axonal population is responsible for facial expressions and tongue movements, compared to muscles in the upper extremity. Sensory axons appear to be responsible for neural feedback from cutaneous mechanoreceptors to control the movement of facial muscles and the tongue. The newly discovered sympathetic axonal population in the facial nerve is hypothesized to be responsible for involuntary control of the muscle tone. These findings shed light on the pivotal role of high efferent input and rich somatosensory feedback in neuromuscular control of finely adjusted cranial systems.