Systemic Sarcoidosis Presenting as Bilateral Optic Neuritis

Sarcoidosis is a multi-systemic inflammatory disease in which non-caseating granuloma occur in different sites producing variable clinical symptoms. Although it can involve various organs including brain and orbits, bilateral optic neuritis as the first symptom of systemic sarcoidosis is rare. Sarcoidosis is a diagnostic challenge, especially if systemic symptoms are absent. We report a patient who presented bilateral optic neuritis as the first manifestation of systemic sarcoidosis without other systemic symptoms including cranial neuropathies or intraocular involvement.

A 4-Year Follow-Up of Subjects with Visually Equivocal Amyloid Positron Emission Tomography Findings from the Alzheimer’s Disease Neuroimaging Initiative Cohort / 대한핵의학회잡지

Background@#To date, the clinical significance of visually equivocal amyloid positron emission tomography (PET) has not been well established. @*Objective@#We studied the clinical significance of equivocal amyloid PET images from the Alzheimer’s Disease Neuroimaging Initiative (ADNI). @*Methods@#Subjects with F-18 florbetapir PET scans at baseline who were followed up for 4 years were selected. Clinical characteristics, imaging biomarkers, cognitive function, and rate of conversion to AD were compared in subjects with visually equivocal findings. @*Results@#Of 249 subjects who completed the follow-up, 153 (61.4%), 20 (8.0%), and 129 (30.5%) were F-18 florbetapir-negative, -equivocal, and -positive, respectively. The mean standardized uptake value ratios (SUVR) of F-18 florbetapir PET were 0.75 ± 0.04, 0.85 ± 0.10, and 1.00 ± 0.09 for each group (p <0.001 between groups), and 15.0%, 70.0%, and 98.7% of patients were quantitatively above the positive threshold. The change in the SUVR of F-18 florbetapir PET was higher in the equivocal (6.09 ± 3.61%, p <0.001) and positive (3.13 ± 4.38%, p <0.001) groups than the negative group (0.88 ± 4.28%). Among the subjects with normal or subjective memory impairment and mild cognitive impairment, 5.3% with negative amyloid PET and 37.5% with positive amyloid PET converted to AD over the 4-year period. None of the equivocal amyloid PET subjects converted to AD during this period.

Visuospatial Dysfunction in Patients With the Right Vestibular Neuritis / 대한평형의학회지

Acute vestibular neuritis (VN) is characterized by acute/subacute vertigo with spontaneous nystagmus and unilateral loss of semicircular canal function. Vestibular system in human is represented in the brain bilaterally with functional asymmetries of the right hemispheric dominance in the right handers. Spatial working memory entails the ability to keep spatial information active in working memory over a short period of time which is also known as the right hemispheric dominance. Three patients (patient 1, 32-year-old female; patient 2, 18-year-old male; patient 3, 63-year-old male) suffered from acute onset of severe vertigo, nausea and vomiting. Patients 1 and 2's examination revealed VN on the right side showing spontaneous left beating nystagmus and impaired vestibular ocular reflex on the right side in video head-impulse and caloric tests. Patient 3's finding was fit for VN on the left side. We also evaluated visuospatial memory function with the block design test in these 3 VN patients which discovered lower scores in patients 1 and 2 and the average level in patient 3 compare to those of healthy controls. Follow-up block design test after resolved symptoms showed within normal range in both patients. Our cases suggest that the patients with unilateral peripheral vestibulopathy may have an asymmetrical effect on the higher vestibular cognitive function. The right VN can be associated with transient visuospatial memory dysfunction. These findings add the evidence of significant right hemispheric dominance for vestibular and visuospatial structures in the right-handed subjects, and of predominant dysfunction in the hemisphere ipsilateral to the peripheral lesion side.

Two Cases of Myasthenia Gravis Showing Fatigibility Presenting with Decreased Gain of Smooth Pursuit / 대한평형의학회지

Myasthenia gravis (MG) is an autoimmune disease caused by autoantibodies to the acetylcholine receptors of the neuromuscular junction characterized by weakness and abnormal fatigability of the muscles. Therefore, the diagnosis of MG depends on the recognition of this distinctive pattern of fatigable weakness. Previous studies presented the diagnostic efficacy of saccadic eye movements in patients with ocular MG. We here in report 2 patients of ocular MG showing the fatigue effects during repetitive sustained smooth pursuit, and the effects of the administration of edrophonium on myasthenic smooth pursuit. Changes in smooth pursuits reflecting peripheral and secondary central mechanisms were demonstrated.

Superior Oblique Myokymia Associated with Neurovascular Cross Compression

Superior oblique myokymia (SOM) is a rare disorder characterized by unilateral paroxysmal oscillopsia or diplopia. Recent studies revealed that SOM can be associated with neuro-vascular cross compression (NVCC) of the trunk of the trochlear nerve. Although it frequently occurs without any underlying systemic disease or concurrent neurologic sign, we need to consider this NVCC especially in cases with persistent disturbing symptoms. Hereby, we present two cases of SOM whose neuroimaging studies suggest NVCCs and, discuss recent update of the pathomechanism of SOM.

Epilepsy and Driving Regulation in Korea

In Korea, current status of epilepsy and driving are challenging and there are lack of formal legal guidelines about driving in patients with epilepsy. According to the default standards in Korean Road Traffic law, patients with epilepsy are restricted or prohibited from driving except who are conditionally allowed to drive by the Aptitude Judgement Committee (AJC). Though the AJC consist of medical doctors and traffic officials, new regulation and guidelines are required for various type of seizure and characteristics of patients with epilepsy. This review outlines the current applicable legislation about epilepsy and driving in Korea as well as that of the overseas country calling for new laws to establish a consistent assessment.

Superior Altitudinal Visual Field Defect as Initial Manifestation of Posterior Reversible Encephalopathy Syndrome

No abstract available.

Focal Subarachnoid Hemorrhage Mimicking Recurrent Transient Ischemic Attack

Focal subarachnoid hemorrhage occasionally presents as transient focal neurologic episodes mimicking transient ischemic attack (TIA). Unless properly diagnosed, it may aggravate cerebral hemorrhage by administering antithrombotic agents. Therefore, clinicians need to be aware that such focal subarachnoid hemorrhage sometimes cannot be detected on noncontrast computed tomography and blood-sensitive magnetic resonance imaging can detect even a small amount of hemorrhage. We describe an 85-year-old woman with focal subarachnoid hemorrhage and possible cerebral amyloid angiopathy who presented transient left arm weakness recurrently, which mimicked TIA.

Clinical Heterogeneity of Anti-GM2-Ganglioside-Antibody Syndrome

BACKGROUND AND PURPOSE: Antiganglioside antibodies are known to play a pathogenic role in Guillain-Barré syndrome (GBS). Either an immunoglobulin (Ig)G- or IgM-type anti-GM2 antibody is detected in rare cases in GBS patients. However, the specific pathogenic role of these antibodies in GBS has not been reported previously. This study aimed to define and characterize the clinical spectrum of GBS with anti-GM2 positivity. METHODS: We reviewed the database of the Dong-A University Neuroimmunology Team, which has collected sera of GBS and its variants from more than 40 general and university-based hospitals in Korea. Detailed information about the involved patients was often obtained and then corrected by the charge doctor applying additional questionnaires. RESULTS: Four patients with acute monophasic peripheral neuropathy or cranial neuropathy with isolated IgM-type anti-GM2-antibody positivity were recruited. In addition, IgG-type anti-GM2 antibody was solely detected in the sera of another four patients. The IgM-positive group comprised heterogeneous syndromes: two cases of acute motor axonal neuropathy, one of acute inflammatory demyelinating polyneuropathy, and one of isolated facial diplegia. In contrast, all of the cases enrolled in the IgG-positive group manifested with dizziness with or without oculomotor palsy due to cranial neuropathy syndrome. CONCLUSIONS: This study has identified that anti-GM2 antibody can be found in various subtypes of GBS and its variants in rare cases. Compared to the clinical heterogeneity of the IgM-positive group, the IgG-positive group can be characterized by cranial-dominant GBS variants presenting mainly with oculomotor and vestibular dysfunctions.

Parasomnia as an Initial Presentation of Narcolepsy

Narcolepsy is characterized by excessive daytime sleepiness, cataplexy, sleep paralysis and hypnagogic hallucinations. Only a few studies have focused on non-rapid eye movement (NREM) and REM parasomnias in narcolepsy. We report a narcolepsy without cataplexy patient presenting parasomnia as an initial symptom. A 18-year-old boy was admitted to hospital for abnormal behavior of sitting up during sleep over 2 years. He had a symptom of lethargy without cataplexy and subjective excessive daytime sleepiness, but his family found him often asleep during daytime. He underwent 3 times of polysomnography (PSG) including 1 multiple sleep latency test (MSLT) after the last PSG. The last PSG showed 1 episode of abrupt sitting. Three sleep REM onset period was observed in MSLT which was not detect in PSG. Parasomnia as an initial symptom of narcolepsy is a rare clinical entity. The MSLT may be useful in the evaluation of patients with parasomnia and unexplained hypersomnia.