Teruaki Masuda

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.

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).

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).

Primary central nervous system lymphoma with cortical laminar hemorrhage.

Here we report a case of primary central nervous system (CNS) lymphoma with cortical laminar hemorrhage. The present case showed an acute onset of focal neurologic signs and bilateral cortical lesions surrounded by peripheral white matter edema on magnetic resonance imaging. A part of the left frontal cortical lesion was hyperintense on T1-weighted images and hypointense on T2-weighted and T2-weighted gradient-echo images, suggesting subacute laminar hemorrhage. The patient was initially diagnosed with multiple hemorrhagic infarctions, but a biopsy specimen revealed diffuse large B-cell lymphoma with hemosiderin deposits. Immunohistochemical studies revealed that the tumor cell cytoplasm and membrane stained positively for anti-vascular endothelial growth factor antibody. The present case reconfirms the danger of making a specific lymphoma diagnosis based on magnetic resonance imaging findings alone and that histopathologic examination following brain biopsy is necessary for a correct diagnosis. Vascular endothelial growth factor expression might be associated with the intratumoral hemorrhage.

Left ventricular undulation in a patient with atrial flutter

An approximately 60-year-old woman was referred to our department for bradycardia. She had been previously diagnosed with myotonic dystrophy and was bedridden for the last 20 years. Electrocardiography showed atrial flutter (AF) with advanced atrioventricular block that persisted for 40 days. The AF rate was 250 beats/min. Transthoracic M-mode echocardiography showed left ventricular undulation [1] at the apex as well as the base (Fig. 1, upper and lower panels). Left ventricular systolic function and left atrial dimension (25 mm) were normal. M-mode color Doppler of the mitral valve through the apical window showed mitral inflow and mitral regurgitation at the pace of AF (Fig. 1, lower panel). On tissue velocity imaging, curved color-coded anatomical M-mode showed a seesawlike relationship between wall motions of the lateral wall and septum (Fig. 2, upper panel). Longitudinal strain tracings of the lateral wall and septum showed that myocardial elongation and shortening occurred at the same pace as that of AF with different time lags (Fig. 2, lower panel). Although the exact mechanisms of this phenomenon are unclear, we believe that different timings of regional myocardial elongation and shortening might have caused left ventricular undulation in this patient.