The Japanese Society of Neurology has held an annual workshop for stroke education since September 2018 for young members of the society and medical students to take an interest in stroke medicine and stroke research and to contribute to conquest of stroke, a national disease. The third annual workshop will be held in the National Cerebral and Cardiovascular Center, Osaka in September 2020 also with the support of the Japan Stroke Society. Designated lecturers are preparing for presentation of their own devising. Here, brief abstracts of educational lectures and special statements on career formation of vascular neurologists are introduced.

Cerebral small vessel disease (SVD) is defined as difficulty maintaining efficient microcirculation, metabolism, and neural networks caused by degeneration of small vessels of the brain, as well as cognitive or physical dysfunction caused by this difficulty. The most common SVD (i.e., type 1 SVD), which is driven by hypertensive arteriopathy, appears to be more prevalent in people with East Asian ethnicity than in Whites. Recent attention has been paid to a SVD scoring system using major MRI markers of SVD in an attempt to comprehensively semi-quantify the SVD burden in the brain. This concept raised a new question: “Is there a practical threshold for the comprehensive SVD score?” The development of computational methods to assess SVD imaging markers could answer this question, and may help identify the optimal intervention for patients with type 1 SVD to prevent stroke and dementia.

Surfer’s myelopathy is non-traumatic spinal cord injury which develops in beginner surfers. The patient was a 17-year-old female who developed severe paraplegia with bilateral sensory dysfunction below the groin and bladder/rectal dysfunctions after her first surfing lesson. A spinal-cord MRI performed six hours after onset revealed an intramedullary hyperintensity area from T8 to the conus medullaris on the T₂ weighted images. Expansion of this hyperintensity area was observed on Day 3 and showed a reduction on Day 8. After providing intravenous methylpredonisolone, intravenous glycerol and intravenous edaravone, motor function and bladder/rectal functions began to improve after approximately three weeks. In this study, the expansion of the lesion in the early stages of the disease course was observed by sequential spinal MRI. Furthermore, a time lag between improvement according to imaging and improvement in symptoms was also observed.

We present the case of an 81-year-old woman who underwent aortic valve replacement and coronary artery bypass surgery by median sternotomy. Following the operation, she experienced distal muscle weakness in her left upper limb and numbness in the medial part of her left forearm and palm. Nerve conduction study revealed low amplitudes of her left ulnar compound muscle action potential (CMAP) and sensory nerve action potential (SNAP), radial CMAP, and medial antebrachial cutaneous SNAP. Needle electromyography showed denervation potentials in the extensor digitorum communis and abductor pollicis brevis. CT and MRI showed a left first rib fracture and a hematoma nearby. Short-T1 inversion recovery image (STIR) showed a high-intensity area in the left root of C8. Based on these findings, we diagnosed the patient with lower trunk brachial plexopathy due to hematoma.

A 59-year-old man with past histories of bronchial asthma and chronic sinusitis underwent transanal resection of anorectal malignant melanoma with general anesthesia. On the third day after surgery, he presented with subacute weakness with right dominant hypoesthesia in the bilateral lower limbs. Tendon reflexes were diminished without pathological reflexes. Blood examination showed increased eosinophils (2,058/μl) and elevated serum immunoglobulin E (675.0 IU/ml). Cerebrospinal fluid examination showed elevated protein (200 mg/dl) without pleocytosis (<5/μl). A nerve conduction study suggested multiple mononeuropathy with motor and axonal dominance in the right tibial, peroneal, and sural nerves. Because of eosinophilia and his past medical history (i.e., bronchial asthma and chronic sinusitis), we initially suspected eosinophilic polyangiitis granulomatosis (EGPA) as the cause of postoperative polyneuropathy. However, his neurological symptoms did not improve despite the decreased eosinophil count after tumor resection, which was inconsistent with EGPA. We biopsied the left sural nerve to exclude EGPA and make a diagnosis. Pathological findings revealed no demyelination, axonal degeneration, or eosinophil infiltration with granuloma formation; however, lymphocyte-dominated inflammation was observed around the epineurial small vessels. Thus, the patient was diagnosed with early onset post-surgical inflammatory neuropathy (PIN) based on his clinical course and the pathological findings. On post-surgery day 48, oral administration of prednisolone (40 mg/day) was started. His neurological symptoms improved quickly and remarkably. Our case suggests that, when multiple mononeuropathy develops early after surgery, PIN should be considered as a differential diagnosis to initiate appropriate treatment based on the pathological condition of neuropathy.

A 74-year-old man was administered nivolumab to treat recurrent squamous cell carcinoma of the lungs. He developed fatigue, redness on the front of his neck, muscle weakness, and difficulty in swallowing after receiving the third course of nivolumab. Physical and neurological examinations showed proximal limb muscle weakness, periorbital erythema, and erythema of the front of his neck as well as fingers. Laboratory investigations revealed elevated serum CK and aldolase levels, and he was diagnosed with dermatomyositis. We initiated steroid pulse therapy and intravenous immunoglobulin therapy; however, he died of advanced lung cancer. Immune checkpoint inhibitor-induced neuromuscular disease is increasingly being observed in clinical practice. We report a rare case of dermatomyositis with squamous cell carcinoma of the lungs secondary to nivolumab treatment.

A 74-year-old man, who received pembrolizumab for the treatment for non-small cell lung cancer, developed quadriparesis 10 days after the first course of treatment accompanied by gait disturbance. Dysesthesia was observed in the distal extremities, and tendon reflexes were absent. Neurological examination and peripheral nerve conduction study supported the diagnosis of Guillain–Barré syndrome-like acute inflammatory demyelinating polyneuropathy caused by pembrolizumab. The administration of pembrolizumab was discontinued. Moreover, he was initially treated with intravenous immunoglobulin therapy, followed by intravenous methylprednisolone therapy and oral prednisolone. The limb weakness improved to a degree that he could walk alone on discharge. Pembrolizumab, which is an immune checkpoint inhibitor with a high anti-tumor effect, is reported to cause various adverse events. However, neuromuscular complications following cancer treatment with immune checkpoint inhibitors are relatively rare. Treatment with corticosteroids is considered to be effective for treating immune-related adverse events. Corticosteroids were effective in treating peripheral neuropathy caused by immune checkpoint inhibitors in this patient. Thorough treatment should be considered with a combination of corticosteroids and immunoglobulin therapy, in addition to discontinuation of immune checkpoint inhibitors, for this rare entity, which differs from that for idiopathic Guillain–Barré syndrome.

A 29 year-old, right-handed woman was admitted to our hospital due to her headache with fever elevation lasting for two months followed by a prolonged loss of awareness with an involuntary movement in her left hand and mouth. This movement appeared very frequently, and the duration was very short, so called “faciobrachial dystonic seizures (FBDS)”. Some of FBDS were followed by prolonged loss of awareness. Brain MRI fluid attenuated inversion recovery (FLAIR) image revealed high intensity lesion in the left mesial temporal lobe. Arterial spin labeling (ASL) image indicated hyper perfusion in this lesion and also the lateral temporal region. No ictal electroencephalography (EEG) change was observed before the onset of FBDS. FBDS was often followed by focal impaired awareness seizure (FIAS) in which ictal EEG showed rhythmic alpha activity arising from left mid-temporal region. This EEG seizure pattern was clearly visible in the time–frequency analysis. Given these clinical findings, along with an evidence of serum anti-leucine-rich glioma-inactivated 1 (LGI1) antibody positive, she was diagnosed with anti-LGI1 encephalitis. Immunotherapy (methylpredonisolone and intravenous immunoglobulin) with a multiple anti-epileptic drugs therapy (lacosamide, perampanel, and lamotrigine) was highly responsible to her symptoms. Although the high intensity lesion in FLAIR image still remained after the treatment, findings of ASL and EEG showed clear correlation to her cognitive function and seizures, respectively. Temporal change in ASL imaging suggested that the hyper perfusion in ASL during the acute stage could be provided by inflammation of the encephalitis its self and also the seizures activities (FBDS and FIAS). The pathophysiological indication of anti-LGI1 encephalitis was limited in terms of the therapeutic strategy, however, our findings collectively suggested that the combination analysis of EEG activity and cerebral blood flow dynamics (ASL) could be the potential candidate.

A 34-year-old man developed right-dominant lower limb paraplegia, and then upper limb paresis with radicular pain following disseminated herpes zoster (HZ) in his right forehead, back of the trunk, and lumbar and right lower limb regions. Cerebrospinal fluid (CSF) findings revealed an increase in lymphocytes (32 cells/μl) and protein content (50 mg/dl), and polymerase chain reaction (PCR) for varicella-zoster virus (VZV) DNA was negative in CSF, but VZV antigen was positive in the patient’s vesicle smear. Lumbar root MRI using 3D Nerve VIEW (Philips) imaging showed high-intensity lesions on the L2–L5 spinal roots with contrast enhancements, and cervical MRI showed similar findings on both sides at the C4–Th1. Peripheral nerve conduction study revealed prolonged distal latency to 4.9 ms, decreased MCV to 38 m/s, and complete loss of F-wave was seen in the right peroneal nerve study. Minimal F-wave latency was prolonged in the right tibial nerve. Thus, the patient was diagnosed with VZV polyradiculoneuritis caused by disseminated HZ. Regarding the possible pathogenesis of polyradiculoneuritis in this patient with disseminated HZ, we speculate that VZV reached by retrograde transmission from the involved peripheral nerves to the spinal ganglia, which, then, produced polyradiculoneuritis.

We report a case of anti-MuSK antibody (Ab)-positive myasthenia gravis (MG) in a patient who developed recurrent right-sided congestive heart failure. The patient presented with right-sided congestive heart failure of unknown etiology, necessitating hospitalization on three occasions over a 6-month period. During the third episode of hospitalization, she developed disturbance of consciousness, and heart failure was attributed to carbon dioxide narcosis. We performed various investigations including an anti-MuSK Ab assay, which showed positive results, and she was diagnosed with MG based solely on anti-MuSK Ab positivity. Selective plasma exchange did not produce a satisfactory therapeutic effect, and she received additional intravenous immunoglobulin, plasmapheresis, and oral immunosuppressive therapy after which she was successfully weaned off the ventilator. This case report highlights the following points: (a) Recurrent right-sided congestive heart failure may be the first manifestation of anti-MuSK Ab-positive MG and, (b) detection of the anti-MuSK Ab alone is a convincing rationale to diagnose patients with MG.

A 37-year-old man who had been on bromvalerylurea (BU) medication for 11 years at a maximum dose of 2,400 mg per day for headache therapy was admitted to our hospital due to gait disturbance. He had weight loss and exanthema all over his body. Cognitive dysfunction, intellectual deterioration, attention disturbance, decreased muscle strength, and decreased vibratory sense in the lower limbs were observed. Brain MRI showed diffuse brain atrophy, and a peripheral nerve conduction examination revealed decreased nerve conduction velocity and action potential amplitude in the extremities. We diagnosed him with chronic BU intoxication based on pseudohyperchloremia, BU detected in the blood, and bromide elevation. By discontinuing BU and performing intravenous infusion, neurological symptoms and exanthema were improved, and peripheral nerve conduction examination findings also improved. There are few reports of peripheral neuropathy cases of chronic BU intoxication; herein we report one such case along with previously reported cases.