Effects of repetitive transcranial magnetic stimulation on cerebral glucose metabolism.

OBJECTIVE: To investigate the mechanisms underlying the effect of repetitive transcranial magnetic stimulation (rTMS) on post-stroke hemiplegia, we assessed alterations in cerebral glucose metabolism. METHODS: Five post-stroke hemiplegic patients (three targeted for upper limb impairment and two targeted for lower limb impairment) aged 62.6 ± 6.1 years (mean ± standard deviation) with a duration since stroke onset of 3.5 ± 3.8 years participated in this preliminary study. Cerebral glucose metabolism was measured twice-before and after rTMS with intensive rehabilitation-using positron emission tomography with [18F]fluorodeoxyglucose. The Asymmetry Index (AI) was calculated to assess laterality of metabolism between the lesional and contralesional motor areas. The alteration rates of AI (%ΔAI) were compared between participants in whom rTMS was effective and ineffective. RESULTS: Two of the three upper-limb-targeted patients and one of the two lower-limb-targeted patients showed motor function improvements following rTMS treatment. All three patients who responded to rTMS had improved laterality of cerebral glucose metabolism in motor areas, commonly in the precentral gyrus, with an %ΔAI of approximately 10%. In contrast, the two patients who did not respond to rTMS had no improvements in laterality. CONCLUSIONS: These results suggest for the first time that improved glucose metabolism is associated with improved motor function after a combination of rTMS and intensive rehabilitation.

Prion diseases reported in the "Annual of the Pathological Autopsy Cases in Japan".

BACKGROUND: For surveillance projects to be successful, it is important to accurately diagnose all patients, without overlooking any cases. Here, we investigated the present clinical diagnostic accuracy for prion diseases in Japan. METHODS: We analyzed volumes of the "Annual of the Pathological Autopsy Cases in Japan", which reported details on 130,105 autopsies conducted from 2007 to 2016 throughout Japan. RESULTS: The clinical diagnosis of patients with prion disease had a specificity of 91.3% and a sensitivity of 96.3%. The autopsy rates were estimated as 17.8% for patients with clinically suspected prion disease and as 1.8% for the entire population. CONCLUSIONS: Despite the good accuracy of clinical diagnoses of prion diseases, a calculated 78.4 patients with prion disease were expected to have gone undiagnosed during the 10-year study period. However, autopsy is estimated to reveal a maximum of only 13.8 of these clinically undiagnosed patients because of the low autopsy rate. The overall autopsy rate, irrespective of any specific disorder, must increase for effective surveillance projects of disease incidence to be conducted.

Dopaminergic function in spinocerebellar ataxia type 6 patients with and without parkinsonism.

BACKGROUND: Although pure cerebellar ataxia is usually emphasized as the characteristic clinical feature of spinocerebellar ataxia type 6 (SCA6), parkinsonism has been repeatedly described in patients with genetically confirmed SCA6. METHODS: We conducted a positron emission tomography study using a combination of [18F]fluoro-L-dopa for dopamine synthesis and [11C]raclopride for dopamine D2 receptor function on six genetically confirmed SCA6 patients, both with and without parkinsonism. To the best of our knowledge, this is the first dopamine receptor imaging study of patients with SCA6. RESULTS: Most patients had somewhat decreased dopaminergic function, and this decrease was significant in the caudate nucleus. In addition, one SCA6 patient with parkinsonism had whole striatal dysfunction of both dopamine synthesis and dopamine D2 receptor function. CONCLUSIONS: The pathology of SCA6 may not be restricted to the cerebellum, but may also be distributed across various regions, including in both presynaptic and postsynaptic dopaminergic neurons to some degree. Patients with SCA6 may show apparent parkinsonism after the progression of neurodegeneration.

Effects of pitavastatin on cerebral blood flow.

BACKGROUND: Hypercholesterolemia has been identified as an important risk factor for stroke. It has been reported that statins might reduce the risk for new or recurrent cardiovascular events and strokes. OBJECTIVE: This paper reports on the effects of pitavastatin on cerebral blood flow in 2 elderly patients. CASE SUMMARY: Two patients, a 72-year-old right-handed Japanese man and a 77-year-old right-handed Japanese woman, both with a history of cerebral infarction, received 6-month treatment with pitavastatin 2 mg/d for complicated hypercholesterolemia. To assess regional cerebral blood flow (rCBF), single-photon emission computed tomography (SPECT) studies with technetium-99m-ethyl cysteinate dimer were carried out before and after pitavastatin administration. Tomography was evaluated using the Easy z Score Imaging System. None of the patients' other treatments, with the exception of pitavastatin initiation, were modified during the treatment period. In both patients, serum total cholesterol concentrations were improved within 3 months of initiation of pitavastatin treatment, with no marked changes in clinical symptoms. In both patients, improvement was found in rCBF on SPECT. The z score of the left parietal lobe in 1 patient was improved, from 2.20 to 1.69. That of the other patient was also improved, from 2.42 to 1.94. CONCLUSION: In both patients, clinically significant improvement in rCBF was found after 6-month treatment with pitavastatin 2 mg/d.

CADASIL with NOTCH3 S180C presenting anticipation of onset age and hallucinations.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited disease leading to strokes and vascular dementia. The average age of onset for stroke is 45 years with a range of about 30 to 70 years. We describe a Japanese CADASIL family showing S180C in the exon 4 of NOTCH3, presenting an anticipation of the onset age for stroke. MRI demonstrated a similar extent of white matter involvement in younger and older individuals, supporting the presence of anticipation. In addition, hallucinations in 71% of affected patients, and delusions in 57% were also described. Our findings in this family suggest that a specific NOTCH3 mutation was related to unique clinical features, although such correlations have seldom been encountered in CADASIL.

[Therapeutic outcome of onabotulinum toxin type A in patients with upper limb spasticity].

Onabotulinum toxin type A treatment for post-stroke upper limb spasticity was investigated to contribute to establishing a standard dosage for Japanese patients. A total of 100 patients participated in the study. The outcome one month (33.6±6.5 days) after the treatment was assessed by the Modified Ashworth Scale (MAS) to estimate the mean effect with a 10-unit injection and the standard dosage expected to improve MAS 1 degree. Average improvement of 263 muscles treated with a higher concentration of 10 units diluted in 0.2 ml was 0.207±0.414 degrees, and that of 231 muscles treated with a lower concentration of 10 units in 0.4 ml was 0.149±0.244 degrees without significant difference among diluted concentrations. To improve MAS 1 degree, 64.6±31.1 units were required for the pectoralis major, 51.2±21.3 units for the teres major, 111.7±48.0 units for the biceps brachii, 51.6±26.8 units for the brachioradialis, 54.1±23.2 units for the brachialis, 34.4±10.7 units for the pronator teres, 64.6±27.9 units for the flexor carpi radialis, 62.4±26.8 units for the flexor carpi ulnalis, 58.5±31.1 units for the flexor digitorum profundus, 69.7±35.1 units for the flexor digitorum superficialis, 24.6±13.4 units for the flexor pollicis longus, and 15.6±11.3 units for the adductor pollicis. Although the results shown here had no significant differences among concentrations, increasing the volume would disturb injection into small muscles, so we considered that a lower volume with a higher concentration should assure larger benefits. It is difficult to make effective injections into all spastic muscles within the officially permitted health insurance dosage of 240 units. Hence, it is advisable to increase the applicable upper limit based on safely achieved cumulative experience.

[Cerebral circulation and metabolism in the patients with higher brain dysfunction caused by chronic minor traumatic brain injury: a study by the positron emission tomography in twenty subjects with normal MRI findings].

Many individuals are affected on their higher brain functions, such as intelligence, memory, and attention, even after minor traumatic brain injury (MTBI). Although higher brain dysfunction is based on impairment of the cerbral circulation and metabolism, the precise relationship between them remains unknown. This study was undertaken to investigate the relationship between the cerebral circulation or cerebral metabolism and higher brain dysfunction. Twenty subjects with higher brain dysfunction caused by chronic MTBI were studied. They had no abnormal MRI findings. The full-scale intelligence quotient (FIQ) were quantitatively evaluated by the Wechsler Adult Intelligence Scale-Revised (WAIS-R), and the subjects were classified into the normal group and the impaired group. Concurrent with the evaluation of FIQ, positron emission tomography (PET) was performed by the steady state method with 15O gases inhalation. Regional cerebral blood flow (rCBF), oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) were calculated in the bilateral frontal, parietal, temporal, and occipital lobe. First, of all twenty subjects, we investigated rCBF, OEF and CMRO2 in all regions. Then we compared rCBF, OEF, and CMRO2 between the normal group and the impaired group based on FIQ score. We also studied the change of FIQ score of 13 subjects 9.3 months after the first evaluation. In addition, we investigated the change of rCBF, OEF and CMRO2 along with the improvement of FIQ score. Although rCBF and OEF of all subjects were within the normal range in all regions, CMRO2 of more than half of subjects was under the lower normal limit in all regions except in the right occipital lobe, showing the presence of "relative luxury perfusion". Comparison of rCBF, OEF and CMRO2 between normal group and impaired group revealed that CMRO2 of the impaired group was significantly lower than that of the normal group in the bilateral frontal, temporal, and occipital lobe. After 9.3 months, FIQ scores of 13 subjects were significantly increased. CMRO2 was significantly increased in the bilateral frontal and temporal lobe, as well as in the right occipital lobe, along with the improvement of FIQ score. It was concluded that higher brain dysfunction caused by chronic MTBI was related to malfunction of neuronal networks based on the generalized decrease of brain oxygen metabolism in all brain regions. Damage to neuronal networks in the bilateral frontal and temporal lobe appeared to play the most important role in higher brain dysfunction.

Oxyhemoglobin changes during cognitive rehabilitation after traumatic brain injury using near infrared spectroscopy.

To investigate cerebral reactions to cognitive rehabilitation tasks, oxyhemoglobin changes were compared in 9 patients with cognitive impairments after traumatic brain injury (TBI) and 47 healthy controls using functional near infrared spectroscopy (fNIRS) during nine cognitive rehabilitation tasks employed at Nagoya City Rehabilitation Center. Forty-seven measurement channels were placed on the frontal to temporal cortices, and organized into seven channel regions. Oxyhemoglobin changes were normalized based on the mean oxyhemoglobin value at the resting state, and integrated throughout a task. Statistical analyses of the differences between the TBI patients and controls were performed with the two-sided Mann-Whitney U test. Oxyhemoglobin changes were high for both controls and TBI patients in the lateral frontal regions. Oxyhemoglobin changes in TBI patients tended to be higher than controls in the medial frontal regions for most training tasks, and significant differences (p < 0.05) were seen for two tasks in the medial frontal regions. Different regions were activated during the tasks in TBI patients compared to controls. fNIRS measurement is useful in the evaluation of changes of neuronal activities during rehabilitation tasks in TBI patients.