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Dive into the research topics where Sonoko Misawa is active.

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Featured researches published by Sonoko Misawa.


Journal of Neurology | 2008

Bickerstaff's brainstem encephalitis and Fisher syndrome form a continuous spectrum: clinical analysis of 581 cases.

Masafumi Ito; Satoshi Kuwabara; Masaaki Odaka; Sonoko Misawa; Michiaki Koga; Koichi Hirata; Nobuhiro Yuki

Whether Bickerstaffs brainstem encephalitis (BBE) is a distinct disease or a subtype of Fisher syndrome (FS) is unclear as there have been no clinical studies with sufficiently large numbers of patients with FS or BBE. Our aim was to clarify the nosological relationship. Medical records of patients suffering acute ophthalmoplegia and ataxia within four weeks of onset were reviewed. BBE was the diagnosis for patients with impaired consciousness, FS for those with clear consciousness and areflexia. Clinical features, neuroimages, and laboratory findings were analyzed. Patients were grouped as having BBE (n = 53), FS (n = 466), or as unclassified (n = 62). The BBE and FS groups had similar features; positive serum anti-GQ1b IgG antibody (68 % versus 83 %), antecedent Campylobacter jejuni infection (23 % versus 21 %), CSF albuminocytological dissociation (46 % versus 76 %), brain MRI abnormality (11 % versus 2 %), and abnormal EEG findings (57 % versus 25 %). BBE (n = 4) and FS (n = 28) subgroups underwent detailed electrophysiological testing. Both groups frequently showed absent soleus H-reflexes, but normal sensory nerve conduction (75 % versus 74 %) and a 1-Hz power spectrum peak on postural body sway analysis (67 % versus 72 %). Common autoantibodies, antecedent infections, and MRI and neurophysiological results found in this large study offer conclusive evidence that Bickerstaffs brainstem encephalitis and Fisher syndrome form a continuous spectrum with variable CNS and PNS involvement.


Neurology | 2006

Autologous peripheral blood stem cell transplantation for POEMS syndrome

Satoshi Kuwabara; Sonoko Misawa; Kazuaki Kanai; Yuriko Kikkawa; Miki Nishimura; Chiaki Nakaseko; Ryuko Cho; Takamichi Hattori

Polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes syndrome is a rare multisystem disorder. Overproduction of vascular endothelial growth factor (VEGF) by plasmocytoma could be responsible for the symptoms. The authors treated four patients with high-dose chemotherapy and autologous peripheral blood stem cell transplantation. Within 6 months, symptoms associated with rapid normalization of serum VEGF levels improved.


Journal of Neurology, Neurosurgery, and Psychiatry | 2006

Long term prognosis of chronic inflammatory demyelinating polyneuropathy: a five year follow up of 38 cases

Satoshi Kuwabara; Sonoko Misawa; Masahiro Mori; Noriko Tamura; M Kubota; Takamichi Hattori

Background: Little is known about long term prognosis and course after immune treatments in chronic inflammatory demyelinating polyneuropathy (CIDP). Objective: To study long term outcomes and prognostic factors in patients with CIDP. Methods: Clinical and electrophysiological findings, responses to immune modulating treatments, and outcomes five years after the start of treatment were reviewed in 38 CIDP patients. Results: Patients were treated with corticosteroids (89%), immunoglobulin infusion (45%), or plasmapheresis (34%), and 58% received combined therapy. Five years after treatment was begun, 10 (26%) of the patients had complete remission (lasting >2 years with normal nerve conduction studies), and 23 (61%) had partial remission (able to walk) with (26%) or without (34%) immune treatments. The remaining five patients (13%) still had severe disability (unable to walk) or treatment dependent relapses. Patients with complete remission more often had subacute onset, symmetrical symptoms, good response to initial corticosteroid treatment, and nerve conduction abnormalities predominant in the distal nerve terminals. In contrast, insidious onset, asymmetrical symptoms, and electrophysiological evidence of demyelination in the intermediate nerve segments were associated with refractoriness to treatment or treatment dependent relapse. Conclusions: The long term prognosis of CIDP patients was generally favourable, but 39% of patients still required immune treatments and 13% had severe disabilities. Mode of onset, distribution of symptoms, and electrophysiological characteristics may be prognostic factors for predicting a favourable outcome.


Muscle & Nerve | 2008

DISSOCIATED SMALL HAND MUSCLE ATROPHY IN AMYOTROPHIC LATERAL SCLEROSIS: FREQUENCY, EXTENT, AND SPECIFICITY

Satoshi Kuwabara; Masahiro Sonoo; Tetsuo Komori; Toshio Shimizu; F. Hirashima; Akira Inaba; Sonoko Misawa; Yuki Hatanaka

Previous studies suggest that in amyotrophic lateral sclerosis (ALS) the abductor pollicis brevis (APB) and first dorsal interosseous (FDI) are more severely involved than abductor digiti minimi (ADM). To elucidate the pattern, frequency, extent, and specificity of such dissociated muscle atrophy in ALS, compound muscle action potentials recorded from APB, FDI, and ADM were analyzed in 77 ALS patients, 171 normal controls, and 196 disease controls. Compared with normal controls, ALS patients had a reduced APB/ADM amplitude ratio (P < 0.001) and FDI/ADM ratio (P < 0.001), whereas patients with other anterior horn diseases showed similar APB/ADM and FDI/ADM ratios to normal values. Decreased APB/ADM ratio was found in 41% of ALS patients, 5% of normal controls, and 4% of disease controls. Prominent muscle atrophy in APB and FDI, with relatively preserved ADM, appears to be specific to ALS. Dissociated hand muscle atrophy presumably reflects part of the pathophysiology and supports the diagnosis of ALS. Muscle Nerve, 2008


Journal of the Neurological Sciences | 2005

Low-frequency transcranial magnetic stimulation for epilepsia partialis continua due to cortical dysplasia.

Sonoko Misawa; Satoshi Kuwabara; Kazumoto Shibuya; Kenji Mamada; Takamichi Hattori

The potential therapeutic role of repetitive transcranial magnetic stimulation (rTMS) in epilepsy has been increasingly recognized. We investigated the effects of low-frequency rTMS in a patient with epilepsia partialis continua (EPC) due to cortical dysplasia. A 31-year-old female patient experienced EPC in the right upper and lower extremities, which had lasted for 15 years without generalized seizures. MRI showed focal megaencephaly around the motor cortex suggestive of cortical dysplasia. A figure of eight magnetic coil was placed over the hand motor area, and 100 stimuli with an intensity at 90% of motor threshold were given at 0.5 Hz. Immediately after rTMS, EPC was nearly abolished. The effects had continued approximately for 2 months, and the second trial resulted in the similar effects and time-course. Low-frequency rTMS was safe and well tolerated in this patient. These findings support the concept that rTMS decreases cortical excitability, and may be an effective treatment for focal partial seizures.


Journal of Neurology, Neurosurgery, and Psychiatry | 2008

Thalidomide reduces serum VEGF levels and improves peripheral neuropathy in POEMS syndrome

Satoshi Kuwabara; Sonoko Misawa; Kazuaki Kanai; Setsu Sawai; Takamichi Hattori; Miki Nishimura; Chiaki Nakaseko

Background: Polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes (POEMS) syndrome is a rare multi-system disorder associated with plasma-cell dyscrasia. Several case series and reports have suggested that high-dose chemotherapy with autologous peripheral blood stem-cell transplantation is efficacious treatment, but this transplantation is not indicated for elderly patients and patients with renal failure. Objective: To investigate the effects of thalidomide treatment for POEMS syndrome. Methods: Nine patients, who were not indicated for high-dose chemotherapy, were treated with thalidomide. Neurological disability scores, nerve conduction studies and serum levels of vascular endothelial growth factor (VEGF) were prospectively examined. VEGF levels were measured by an enzyme-linked immunosorbent assay. Results: During follow-up periods of 8–23 months (mean, 15 months), all patients showed substantial clinical improvement (n = 6) or stabilisation of symptoms (n = 3). Serum VEGF levels decreased in all patients and were normalised in five patients. Nerve conduction velocities in the median nerve increased in seven patients. There were no serious adverse effects, including thalidomide neuropathy. Conclusion: Thalidomide treatment should be further studied as a treatment for POEMS syndrome, particularly for patients who are not indicated for transplantation therapy.


Neurology | 2011

Ultrasonographic detection of fasciculations markedly increases diagnostic sensitivity of ALS.

Sonoko Misawa; Yu-ichi Noto; Kazumoto Shibuya; Sagiri Isose; Yukari Sekiguchi; Saiko Nasu; Satoshi Kuwabara

Objectives: To study the utility of muscle ultrasound (US) for detection of fasciculations and its contribution to diagnosis in amyotrophic lateral sclerosis (ALS). Fasciculations are characteristic features of ALS, and US can detect them easily and reliably. New diagnostic criteria for ALS, the Awaji algorithm, reintroduced fasciculations as evidence of acute denervation equivalent to that of fibrillations and positive sharp waves. Methods: In 81 consecutive patients with sporadic ALS, we prospectively performed needle EMG and US in 6 muscles (tongue, biceps brachii, first dorsalis interosseous, paraspinalis, vastus lateralis, and tibialis anterior), and diagnostic category were determined by revised El Escorial criteria and Awaji criteria. Results: Fasciculations were much more frequently detected by US than by EMG in the tongue (60% vs 0%), biceps brachii (88% vs 60%), and tibialis anterior muscles (83% vs 45%). The proportion of the patients with definite or probable ALS was 48% by revised El Escorial criteria and 79% by Awaji criteria using US. Conclusions: Muscle US is a practical and efficient tool to detect fasciculations, particularly in the tongue. A combination of US and EMG substantially increases the diagnostic sensitivity of ALS.


Neurology | 2004

Does Campylobacter jejuni infection elicit “demyelinating” Guillain–Barré syndrome?

Satoshi Kuwabara; Kazue Ogawara; Sonoko Misawa; Michiaki Koga; Masahiro Mori; Akiyuki Hiraga; T. Kanesaka; Takamichi Hattori; Nobuhiro Yuki

Background: Campylobacter jejuni enteritis is the most common antecedent infection in Guillain–Barré syndrome (GBS). C. jejuni-related GBS is usually acute motor axonal neuropathy (AMAN), but previous reports described many cases of the demyelinating subtype of GBS (acute inflammatory demyelinating polyneuropathy [AIDP]) after C. jejuni infection. Objective: To investigate whether C. jejuni infection elicits AIDP. Methods: In 159 consecutive patients with GBS, antibodies against C. jejuni were measured using ELISA. Antecedent C. jejuni infection was determined by the strict criteria of positive C. jejuni serology and a history of a diarrheal illness within the previous 3 weeks. Electrodiagnostic studies were performed weekly for the first 4 weeks, and sequential findings were analyzed. Results: There was evidence of recent C. jejuni infection in 22 (14%) patients. By electrodiagnostic criteria, these patients were classified with AMAN (n = 16; 73%) or AIDP (n = 5; 23%) or as unclassified (n = 1) in the first studies. The five C. jejuni-positive patients with the AIDP pattern showed prolonged motor distal latencies in two or more nerves and had their rapid normalization within 2 weeks, eventually all showing the AMAN pattern. In contrast, patients with cytomegalovirus- or Epstein–Barr virus-related AIDP (n = 13) showed progressive increases in distal latencies in the 8 weeks after onset. Conclusion: Patients with C. jejuni-related Guillain–Barré syndrome can show transient slowing of nerve conduction, mimicking demyelination, but C. jejuni infection does not appear to elicit acute inflammatory demyelinating polyneuropathy.


Journal of Neurology, Neurosurgery, and Psychiatry | 2002

Distribution patterns of demyelination correlate with clinical profiles in chronic inflammatory demyelinating polyneuropathy

Satoshi Kuwabara; Kazue Ogawara; Sonoko Misawa; Masahiro Mori; Takamichi Hattori

Background: Chronic inflammatory demyelinating polyneuropathy (CIDP) is a heterogeneous disorder having a wide clinical range, and is characterised by multifocal demyelination that can involve the distal nerve terminals, intermediate nerve segments, and nerve roots. Objective: To investigate whether the distribution patterns of demyelination along the course of the nerve correlate with clinical profiles in patients with CIDP. Methods: Motor nerve conduction studies were carried out on 42 consecutive patients. According to the physiological criteria for demyelination, the presence of a demyelinative lesion was determined in the distal nerve segments (distal pattern) or intermediate nerve segments (intermediate pattern), or in both (diffuse pattern). The serum concentration of tumour necrosis factor (TNF)-α was measured by immunoassay. Results: Patients were classified as having a distal (n=10), intermediate (n=13), or diffuse (n=15) pattern, or were unclassified (n=4). Patients with the distal or diffuse pattern had common clinical features such as subacute onset, symmetric symptoms, and weakness involving proximal as well as distal muscles. Patients with the distal pattern had a good response to treatment and a monophasic remitting course, but the diffuse pattern was associated with a treatment dependent relapsing course, reflecting longer disease activity. The serum TNF-α concentrations increased only in the “diffuse” subgroup of patients, and this might be associated with breakdown of the blood-nerve barrier and therefore, involvement of the intermediate segments. The intermediate pattern was characterised by a chronic course, asymmetric symptoms, less severe disability, and refractoriness to treatments. Conclusions: CIDP consists of subtypes with varying predilections for lesions along the course of the nerve. The distribution patterns of conduction abnormalities may be useful in the prediction of outcome of patients with CIDP.


Journal of Neurology, Neurosurgery, and Psychiatry | 2012

Different neurological and physiological profiles in POEMS syndrome and chronic inflammatory demyelinating polyneuropathy

Saiko Nasu; Sonoko Misawa; Yukari Sekiguchi; Kazumoto Shibuya; Kazuaki Kanai; Yumi Fujimaki; Shigeki Ohmori; Satsuki Mitsuma; Shunsuke Koga; Satoshi Kuwabara

Background POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein and skin changes) syndrome, a rare cause of demyelinating neuropathy associated with multiorgan involvement, has been increasingly recognised. Polyneuropathy is often an initial manifestation and therefore the disorder can be misdiagnosed as chronic inflammatory demyelinating polyneuropathy (CIDP). Objective To elucidate whether POEMS syndrome and CIDP are differentiated based on profiles of neuropathy. Methods Clinical and electrophysiological data were reviewed in consecutive POEMS syndrome (n=51) and typical CIDP (n=46) patients in a single Japanese hospital between 2000 and 2010. Results Both POEMS and CIDP patients showed symmetric polyneuropathy, physiological evidence of demyelination (70% of POEMS patients fulfilled the electrodiagnostic criteria for definite CIDP) and albuminocytological dissociation; 49% of the POEMS syndrome patients had neuropathy onset and 60% of them were initially diagnosed as having CIDP by neurologists. Clinically, POEMS neuropathy more frequently showed severe leg pain (76% vs 7%; p<0.001), muscle atrophy (52% vs 24%; p=0.005) and distal dominant muscle weakness. Electrophysiologically, POEMS syndrome was characterised by less prolonged distal motor latency (mean 5.6 ms vs 8.1 ms; p<0.001) and higher terminal latency index (0.42 vs 0.33; p=0.006) in the median nerves, and unrecordable tibial and sural responses (p<0.001), suggesting demyelination predominant in the nerve trunk rather than in the distal nerve terminals, and axonal loss in the lower limb nerves. Conclusions Before development of typical systemic manifestations, POEMS neuropathy can be distinguished from CIDP by the clinical profile and patterns of nerve conduction abnormalities. Recognition of these features leads to early diagnosis and proper treatment for POEMS syndrome.

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