I have reviewed the utility of clinical neurophysiological examinations in recently highlighted functional neurological disorders (FND) focusing mainly on functional movement disorders (FMD). There are many neurophysiological methods useful for diagnosis of FMD. I will hereafter summarize a few of them in the following part. Surface EMG: This is one of minimally required examinations for clinical analysis of movement disorders. It plays roles in the exclusion of organic disorders and showing positive findings to support FND, especially for functional tremor. The power spectral analysis of surface EMG clearly proves a few useful findings, such as entrainment, distraction and others. Somatosensory evoked potential (SEP): Giant SEP is critical because it proves organic disorders with hyperexcitability of the sensory cortex. Single pulse transcranial magnetic stimulation (TMS): Normal motor evoked potential (MEP) showing intact corticospinal tracts is a positive finding for functional paresis patients. It is also useful to exclude the corticospinal tracts organic dysfunction. Jerk-locked back averaging (JLA), bereitschaftspotential (BP), event related desynchronization (ERD): These are sometimes used for functional disorders, but their clinical validity remains to be determined.

We conducted a targeted literature review on patient burden during the interictal period of migraine. The results of the literature review revealed that: (1) migraine-associated burden persists into the interictal period and is not confined to the headache episodes themselves; (2) anxiety over the possible recurrence of headache episodes is a factor that reduces daily activities and quality of life (QOL); and (3) prophylactic treatment with calcitonin gene-related peptide (CGRP) antibody drugs may reduce the burden during the interictal period. From these findings, it is considered important in migraine treatment to identify the unmet needs of patients, including the burden during the interictal period, and to select an appropriate treatment method based on the burden experienced by individual patients.

Forty-five cases with aquaporin-4 antibody-positive neuromyelitis optica spectrum disorders (NMOSD) who underwent convalescent rehabilitation were studied. After excluding three cases with recurrence during rehabilitation treatment, the Expanded Disability Status Scale of Kurtzke improved a median of 1 point. Corticosteroids were the most used disease-modifying drugs (DMDs). Three cases relapsed during rehabilitation treatment. Six cases developed febrile infections. Thirty-four cases were discharged home, but half of the cases in their 80s were transferred to a medical care hospital. In the rehabilitation treatment of NMOSD, reducing the risk of recurrence by appropriate DMDs and preventing infections are important. Information sharing using a regional collaborative medical care plan is useful.

The patient was a 69-year-old right-handed woman. She had sensory aphasia, and the brain MRI revealed a subacute phase hemorrhage in the left subcortical temporal lobe. We speculated that the patient had post-ictal aphasia due to symptomatic epileptic seizures associated with cerebral hemorrhage. Seven months later, she was readmitted to the hospital with sensory aphasia; however, this time, the brain MRI FLAIR demonstrated high signal in the left medial temporal lobe and thalamic pillow. Furthermore, the electroencephalogram showed periodic discharges focused on the left temporal region. ¹²³I-IMP SPECT of cerebral blood flow indicated a cluster within the medial left temporal lobe. Aphasia associated with nonconvulsive seizures was considered. Sudden onset sensory aphasia should be differentiated from ictal and post-ictal aphasias.

A 56-year-old woman who presented with left drop foot and low back pain a week after the onset of diarrhea. Neurological symptoms progressed for a week and gradually improved thereafter. No weakness was observed in upper limbs and clearly asymmetrical muscle weakness was observed in left lower limbs during the course of the disease. Nerve conduction study demonstrated absent motor responses in the left tibial and fibular nerves, and compound muscle action potentials in the right tibial nerve was decreased in amplitude without conduction slowing. Serum IgG anti-GalNAc-GD1a antibody and anti-ganglioside complex antibodies were positive. Based on these findings, we diagnosed her as a rare variant of Guillain–Barré syndrome (GBS) with marked asymmetrical muscle weakness. In the literature, GBS patients with asymmetrical muscle weakness often have anti-ganglioside antibodies associated with acute motor axonal neuropathy. A detailed history taking and information on the clinical course are helpful for accurate diagnosis of GBS with atypical distribution of weakness.

A 61-year-old man with chronic renal failure had an embolic stroke of undetermined source that was treated with warfarin. Five weeks later, the patient contracted coronavirus disease (COVID-19). Six days after the onset of COVID-19, high blood pressure (>200 ‍mmHg) and consciousness disturbance were reported. CT demonstrated symmetrical hypodensity areas in the bilateral cerebellar hemispheres. MRI revealed hyperintensity lesions in the bilateral cerebellar hemispheres and pons on the T₂-weighted and fluid-attenuated inversion recovery images. Moreover, cerebellar lesions appeared as hyperintensity areas on apparent diffusion coefficient mapping. Based on these findings, a diagnosis of posterior reversible encephalopathy syndrome (PRES) was made. The patient was treated with antihypertensive drugs, and the consciousness level improved gradually. MRI after one month showed that the lesions had disappeared. PRES should be considered if the brain CT of patients with COVID-19 shows a low-density lesion, especially in patients with risk factors for PRES such as chronic renal failure or hypertension.

A 52-year-old woman presented with the subacute onset of pantalgia, fever and consciousness disturbance. MRI revealed widespread symmetrical high-intensity areas along the sulci in both cerebral hemispheres on diffusion-weighted imaging (DWI). Rheumatoid meningitis was suspected based on elevated levels of anti-cyclic citrullinated peptide antibodies (ACPA) in both serum and cerebrospinal fluid (CSF), as well as an elevated ACPA index. Brain biopsy revealed marked infiltration of inflammatory cells in the subarachnoid space, confirming the diagnosis of rheumatoid meningitis. The patient fully recovered after receiving six courses of steroid pulse therapy, followed by postremission therapy. Diagnosing cases without arthritis can be challenging, but testing for ACPA and evaluating the ACPA index can be useful for both diagnosis and assessing therapeutic efficacy in cases of suspected rheumatoid meningitis.

A 49-year-old female was admitted to our hospital due to acute-onset dysarthria and unstable gait. Brain MR diffusion weighted imaging revealed high signal intensities in the midbrain. Brain tumors, abscess and demyelinating lesions was suspected firstly as etiology of the lesion and antibiotics and antiviral drug were started under consulting with the neurosurgeon about brain biopsy. However, despite these treatment her symptoms were deteriorated gradually and intravenous high dose methylprednisolone was added. Since starting this treatment, her symptoms had been improving and the same treatment was repeated once and oral administration of prednisolone (0.5 ‍mg/kg/day) was started. Based on the positive for anti myelin oligodendrocyte glycoprotein (MOG) antibody in the serum, she was ultimately diagnosed with MOG related rhombencephalitis and discharged to her home on the 45th day. After discharge, new paroxysmal symptoms such as paroxysmal dysarthria and ataxia (PDA) had appeared whose symptoms occurred several times a day and lasted for a few seconds to several tens of seconds. These symptoms were regarded as PDA secondary to sequelae of MOG related rhombencephalitis and oral administration of Carbamazepine was started. After the treatment, the symptoms completely disappeared. The differential diagnosis of midbrain tegmental lesions should consider MOG antibody-associated disease, and in cases where delayed-onset PDA occurs, carbamazepine may be effective.

Just like the title, a well-written abstract is crucial for submitting your case report to conferences or medical journals. Authors should write the abstract following four key principles. First, one should be guided by the ABCs of writing—accurate, brief, and clear. Do not include unnecessary information. Second, the abstract is not the preview. Abstracts should be stand-alone. Do not write ‘we report this case, adding discussion with the literature’ or ‘additional cases are needed in future’ at the end of the abstract. Third, do not simply focus on the rarity of the case. Avoid writing statements such as ‘we report this case because it is a rare, valuable/worthful case’. The abstract of a case needs a clear ‘learning point’ for readers. Lastly, carefully confirm and follow the guidelines of target conferences or journals.