New methods for the diagnosis and new treatments for Parkinson’s disease (PD) were explained. As imaging tools, neuromelanin imaging using brain MRI, meta-iodobenzylguanidine (MIBG) cardiac scintigraphy, dopamine transporter scintigraphy, and transcranial sonography were introduced. Olfactory dysfunction and REM sleep behavior disorders (RBD), which are important non-motor symptoms, and the new Clinical Criteria for PD launched by Movement Disorder Society (MDS) were also described. Investigative new medications and new anti-PD medications, which recently became available in Japan, were introduced. I explained the rationale of early treatment, strategy of initial treatment, the significance of continuous dopaminergic stimulation, strategy of treatment for advanced PD, and deep brain stimulation as a surgical treatment together with promising new treatments including gene therapy and cell transplantation.

The delays in the approval and development of neurological drugs between Japan and other countries have been a major issue for patients with neurological diseases. The objective of this study was to analyze factors contributing to the delay in the launching of neurological drugs in Japan. We analyzed data from Japan and the US for the approval of 42 neurological drugs, all of which were approved earlier in the US than in Japan, and examined the potential factors that may cause the delay of their launch. Introductions of the 42 drugs in Japan occurred at a median of 87 months after introductions in the US. The mean review time of new drug applications for the 20 drugs introduced in Japan in January 2011 or later (15 months) was significantly shorter than that for the other 22 drugs introduced in Japan in December 2010 or earlier (24 months). The lag in the Japan’s review time behind the US could not explain the approval delays. In the 31 of the 42 drugs, the application data package included overseas data. The mean review time of these 31 drugs (17 months) was significantly shorter than that of the other 11 drugs without overseas data (26 months). The mean approval lag behind the US of the 31 drugs (78 months) was also significantly shorter than that of the other 11 drugs (134 months). These results show that several important reforms in the Japanese drug development and approval system (e.g., inclusion of global clinical trial data) have reduced the delays in the clinical development of neurological drugs.

A 77-year-old man showed an asymptomatic meningeal lesion beneath the dura matter in the left fronto-parietal region on MRI during an examination for recurrent hoarsness. The lesion showed no gadolinium enhancement, and extended to neither the sulci nor skull. Neurological examinations revealed hoarseness, cochlear and vestibular dysfunction of the right ear, and mildly decreased Achilles tendon reflexes bilaterally. Laboratory findings showed marked inflammatory responses, but no abnormalities for LDH, IgG4, angiotensin-converting enzyme, or soluble IL-2 receptor. There was no serum monoclonal protein. Autoantibody panels in the serum were unremarkable except for an elevation of anti-type II collagen antibodies to a borderline value. Cerebrospinal fluid analysis disclosed an elevated protein concentration (152 mg/dl) and IgG index (1.41) with normal cell counts, negative results for bacterial/tubercular infection, and a normal cytology. ¹⁸F-fluorodeoxyglucose positron emission tomography showed increased uptake in the left frontal region (Max SUV: 7.54). Swelling of the vocal cord, arytenoid cartilage, false vocal cord, and vocal cord palsy on the right side were seen on laryngoscopy, all of which were ameliorated by dexamethasone administration. A meningeal biopsy contained the dura matter and arachnoid, in which a granulation composed of massive mature plasma cells with many Russel bodies, accompanied by occasional lymphocytes and histiocytes were observed. Three months after the biopsy, he developed bilateral auricular chondritis and conjunctivitis. Based on these findings, we diagnosed him with relapsing polychondritis (RP). Prednisolone administration (40 mg/day) improved the chondritis and meningeal lesion. Central nervous system involvement is rare in patients with RP, and meningeal complications, such as aseptic meningitis or pachymeningitis, are mostly observed after the diagnosis of RP. However, due to its rarity, it still remains to be clarified whether a similar pathogenesis of meningeal complications underlies RP. The present case is indicative in that predominant meningeal granuloma arose during chondritis of several portions that had gradually developed, which suggests that meningeal complications could be derived from RP.

We reported a 32-year-old man who was a sporadic case of myotonic syndrome with muscle stiffness or transient weakness of limbs upon initiating movements after rest. On examination, he showed painless myotonia with warm-up phenomenon, Hercules-like hypertrophic musculature and myotonic discharges in EMG. The clinical findings resembled to those of Becker disease rather than Thomsen disease. But electrodiagnosis suggested sodium channel myotonia instead of chloride channelopathy. Genetic testing detected a novel missense mutation (p.V1166A) in the SCN4A gene but not in the CLCN1 gene. Transient weakness upon initiating movements is usually observed in Becker disease but rare in Thomsen disease, which is not reported in sodium channel myotonia so far. He was probably the first case of sodium channel myotonia with transient weakness upon initiating movements, which was confirmed by 10 Hz repetitive nerve stimulation test as depolarization block.

A 57-year-old right-handed man was admitted to our hospital because of right facial paresis and acute-onset dysarthria. He presented with non-fluent aphasia. His aphasia gradually improved, but he started speaking with a strange accent and intonation from the fifth hospital day. He was diagnosed with foreign accent syndrome (FAS), which lasted for 2 months. MRI revealed ischemic infarction with edema in the superior, middle, and inferior parts of the left precentral gyrus. One year later, MRI revealed old, small infarct lesions in the left precentral gyrus, middle frontal gyrus, and postcentral gyrus. We suspected that FAS developed because of disturbance of prosody in the speaking network on improving his aphasia. His meticulous character was probably influenced on developing FAS. The responsible lesions possibly were those in the reversible parts of the left precentral gyrus with edema on acute stage.

We report a case of flexion contractures in a patient’s legs secondary to postpartum hypopituitarism. A 56-year-old woman presented with a 3-year history of worsening flexion contractures of the hips and knees. On admission, her hips and knees could not be extended, and she had muscle stiffness and tenderness to palpation of the lower extremities. We first suspected stiff-person syndrome or Isaacs’ syndrome because of her muscle stiffness. However, multiple hormones did not respond to stimulation tests, and an MRI of the brain showed atrophy of the pituitary gland with an empty sella. A subsequent interview revealed that she had suffered a severe hemorrhage while delivering her third child. She was diagnosed with panhypopituitarism and started on cortisol replacement therapy. After 1 week of treatment with hydrocortisone (10 mg/day), her symptoms quickly improved. We then added 75 μg/day of thyroid hormone. During the course of her treatment, autoantibodies against VGKC complex were found to be weakly positive. However, we considered the antibodies to be unrelated to her disease, because her symptoms improved markedly with low-dose steroid treatment. There are a few reports describing flexion contractures of the legs in patients with primary and secondary adrenal insufficiency. As these symptoms are similar to those seen in stiff-person syndrome, adrenal and pituitary insufficiency should be taken into account to achieve the correct diagnosis and treatment in patients with flexion contractures and muscle stiffness.

A 65-year-old man had a transient amnesia for about 3 hours. Similar symptoms appeared three years ago. He did not manifest dementia, cerebellar ataxia and involuntary movements. Peripheral neuropathy was observed by the neurophysiological examinations. Diffusion weighted image showed high intensity signal in the area of the corticomedullary junction of the frontal to parietal lobes and immunohistochemical studies of biopsied skin revealed many intranuclear inclusion bodies. Adult-onset neuronal intranuclear inclusion disease was diagnosed. As there was no similar member in his family, he was a sporadic case. Clinical characteristics of his amnesia was fulfilled with the criteria of transient global amnesia (TGA). The transient disturbance of limbic system was suspected.

A 55-year-old man was admitted with paralysis of the left lower leg. He had purpura in the left lower extremity for three years, left calf pain for two years, and dysesthesia in the left plantar region and first toe for one year. A physical examination revealed livedo reticularis on the left leg and mononeuritis multiplex was diagnosed in the bilateral tibial and left peroneal nerve area. Anti-neutrophil cytoplasmic antibody was negative. A nerve conduction study showed decreased amplitude of compound muscle-action potential in the bilateral tibial and the left peroneal nerve, sensory nerve action potential in the bilateral sural nerve. A skin biopsy revealed inflammatory cells on blood vessel walls and cutaneous arteritis was diagnosed. Cyclophosphamide pulse therapy with steroid and anti-coagulation improved the neurological symptoms. A skin biopsy should be considered when patients present with mononeuritis multiplex in the lower extremities and cutaneous findings such as livedo reticularis in the symptomatic area.