Takuya Hanaoka

Brain perfusion differences in Parkinsonian disorders

We aimed to objectively examine the brain perfusion differences between PD, Parkinson variant of multiple system atrophy, and progressive supranuclear palsy. 99mTc ethylcysteinate dimer single‐photon emission CT (SPECT) was performed in 28 patients with PD, 12 with Parkinson variant of multiple system atrophy, 19 with progressive supranuclear palsy, and 17 age‐ and sex‐matched control subjects. A voxel‐by‐voxel group analysis, using statistical parametric mapping 8, was performed to detect the differences of regional cerebral blood flow among three diseases and control groups. Regional cerebral blood flow was measured using the noninvasive Patlak plot method and calculated using a fully automated region of interest technique. Progressive supranuclear palsy showed decreased regional cerebral blood flow in the cingulate gyrus and thalamus, whereas Parkinson variant of multiple system atrophy showed decreased regional cerebral blood flow in the cerebellum, compared with other patients and controls. Regional cerebral blood flow in the thalamus could be used to discriminate progressive supranuclear palsy from other diseases and control subjects with high sensitivity. These findings suggest that parkinsonian disorders, such as PD, Parkinson variant of multiple system atrophy, and progressive supranuclear palsy show a distinct SPECT pattern in the frontal cortex, thalamus, and cerebellum. Moreover, the measurements of regional cerebral blood flow in the thalamus and cerebellum may be helpful in screening for the differential diagnosis of parkinsonian syndrome.

Corticobasal degeneration presenting with progressive conduction aphasia

We report the case of a woman with primary progressive aphasia (PPA) presenting with conduction aphasia. Neurological findings showed bilateral finger tremor and signe de poignet figé in her right hand. Memory, orientation, and activities of daily living were well preserved. Linguistic examination showed severe impairment in repetition, fluent spontaneous speech with phonemic paraphasia, and relatively well preserved comprehension. Limb-kinetic apraxia and parkinsonism were not observed during the course of her illness. T1-weighted magnetic resonance imaging revealed severe atrophy of the left temporal lobe and dilatation of the left Sylvian fissure. Neuropathological findings demonstrated the most severe atrophy in the left superior temporal gyrus and Gallyas-Braak-positive or phosphorylated tau-immunoreactive cytoskeletal structures, which were consistent with corticobasal degeneration (CBD). We speculate that the progressive conduction aphasia of our patient might have been caused by left temporal lobe impairment. We suggest that progressive conduction aphasia may be a feature of CBD presenting with PPA.

Evaluation of the effect of thyrotropin releasing hormone (TRH) on regional cerebral blood flow in spinocerebellar degeneration using 3DSRT

Thyrotropin releasing hormone (TRH) therapy improves cerebellar ataxia in patients with spinocerebellar degeneration (SCD). We investigated the effect of TRH on regional cerebral blood flow (rCBF) using the fully automated region of interest (ROI) technique, 3DSRT. Ten patients with SCD received TRH intravenously (2 mg/day) for 14 days and underwent brain perfusion single photon emission computed tomography before and after therapy. Clinical efficacy was assessed using the International Cooperative Ataxia Rating Scale (ICARS). The rCBF in each ROI was measured using the noninvasive Patlak plot method and calculated using 3DSRT. TRH significantly improved the ICARS scores and increased rCBF in the callosomarginal segment and cerebellum. Cerebellar rCBF increased in 4 of 5 patients with improved ICARS scores and in 3 of 5 patients without improved ICARS scores after TRH therapy. The correlation between the change in cerebellar rCBF and the improved ICARS score, however, was not significant. These findings indicate that TRH therapy may increase cerebellar rCBF in some patients with cerebellar forms of SCD and that 3DSRT may be useful for evaluating the efficacy of TRH for increasing CBF. The beneficial effects of TRH may be due to increased cerebellar rCBF or the increased rCBF may be a secondary effect of TRH therapy.

Evaluation of the effects of thyrotropin releasing hormone (TRH) therapy on regional cerebral blood flow in the cerebellar variant of multiple system atrophy using 3DSRT.

Thyrotropin releasing hormone (TRH) improves cerebellar ataxia and cerebellar perfusion in patients with spinocerebellar degeneration. It is not known whether TRH therapy can improve the cerebellar regional cerebral blood flow (rCBF) or not in patients with cerebellar variant of multiple‐system atrophy (MSA‐C).

Relationship between white matter lesions and regional cerebral blood flow changes during longitudinal follow up in Alzheimer's disease.

The aim of the present study was to evaluate the relationship between baseline white matter lesions (WML) and changes in regional cerebral blood flow during longitudinal follow up of patients with Alzheimers disease (AD).

Monofocal large inflammatory demyelinating lesion, mimicking brain glioma

Here we report two cases of pathologically confirmed tumor-like demyelinating lesions. In comparison with common primary demyelinating diseases, our cases demonstrated atypical radiologic features, such as a large monofocal lesion with mild brain edema, and open ring-like or focal enhancement on magnetic resonance images, suggesting brain tumors. The clinical manifestations included focal neurologic signs due to the lesions, monophasic episodes without relapse over a long follow-up period, and efficacy of oral corticosteroid therapy. Histological analysis of brain biopsy specimens showed the inflammatory demyelination and preserved axons without tumor cells. The present cases suggest the importance of considering inflammatory demyelinating disease in the different diagnosis of monofocal tumor-like lesion.

Evaluation of the Regional Cerebral Blood Flow Changes during Long-Term Donepezil Therapy in Patients with Alzheimer's Disease Using 3DSRT

We attempt to evaluate objectively the regional cerebral blood flow (rCBF) changes during long‐term donepezil therapy and the relationship between the clinical response and rCBF change in patients with Alzheimers disease (AD).

Relationship between thyroid hormone levels and regional cerebral blood flow in Alzheimer disease.

Subclinical thyroid disease and even variations in thyroid function within the normal range is associated with cognitive function and a risk of Alzheimer disease (AD). Several studies reported the effect of thyroid hormones on cerebral blood flow. The aim of this study was to objectively evaluate regional cerebral blood flow (rCBF) in association with thyroid hormone levels within the normal range in patients with AD. Serum thyroid-stimulating hormone (TSH), free T3, and free T4 levels were measured in 62 patients with AD (23 men and 39 women; age 56 to 91 y; mean age 77.3 y) and 27 control subjects (9 men and 18 women; age 61 to 93 y; mean age 75.8 y). The 99mTc ethylcysteinate dimer single photon emission computed tomography was performed in all subjects. The rCBF in the region of interest was measured by the noninvasive Patlak plot method and calculated using FineSRT, which is a fully automated region of interest technique. No significant correlation was found between thyroid hormone levels and Mini-Mental State Examination scores or global CBF values. Serum levels of TSH, but not free T3 or free T4, were significantly inversely correlated with rCBF in the middle and inferior temporal regions of right cerebral hemisphere in patients with AD. Control subjects showed no significant correlation between thyroid hormone levels and rCBF. Although these findings of a regional relationship must be considers preliminary, this study proposed the hypothesis that altered TSH levels within the normal range may be related to brain perfusion in right temporal region.

Creutzfeldt-Jakob Disease with a prion protein gene codon 180 mutation presenting asymmetric cortical high-intensity on magnetic resonance imaging

ABSTRACT. Here we report a genetically confirmed case of Creutzfeldt-Jakob disease with a prion protein gene codon 180 mutation presenting atypical magnetic resonance imaging findings. The present case exhibited an acute onset and lateralized neurologic signs, and progressive cognitive impairment. No myoclonus or periodic synchronous discharges on electroencephalography were observed. Diffusion-weighted images revealed areas of high signal intensity in the right frontal and temporal cortices at onset that extended to the whole cortex and basal ganglia of the right cerebral hemisphere at 3 months. Although the cerebrospinal fluid (CSF) was initially negative for neuron specific enolase, tau protein, 14–3–3 protein, and abnormal prion protein, the CSF was positive for these brain-derived proteins at 3 months after onset.

Evaluation of Regional Cerebral Blood Flow in Alzheimer's Disease Patients with Subclinical Hypothyroidism

Background: This study examined regional cerebral blood flow (rCBF) in Alzheimers disease (AD) patients with and without subclinical hypothyroidism (SCH). Methods: Eleven AD patients with SCH and 141 AD patients without SCH underwent brain perfusion single photon emission computed tomography (SPECT). The SPECT data were analyzed by statistical parametric mapping (SPM8) and FineSRT. Results: AD patients with SCH showed a significantly decreased rCBF mainly in the temporal lobe and thalamus, whereas those without SCH showed a significantly decreased rCBF in the parietotemporal lobe and cingulate gyrus as well as the frontal lobe. Conclusion: Our findings suggest that SCH may affect cerebral perfusion in regions associated with the memory function.