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Biomedical subjects

Y Takase

Publications and source records attributed to Y Takase.

152 records · Page 9Linked to original sources

Diffusion-weighted echo-planar MR imaging: clinical applications and pitfalls -- a pictorial essay.

Diffusion-weighted imaging (DWI) provides unique information about various pathological changes of the brain. DWI is sensitive for the detection of hyperacute infarcts, and useful in distinguishing acute or subacute infarcts from chronic infarcts. DWI is useful in differentiating cytotoxic edema from vasogenic or interstitial edema, which may help to determine prognosis. DWI is useful in differentiating cystic or necrotic tumors from abscesses or epidermoids. DWI can discriminate nonenhanced tumor infiltration from vasogenic edema, and differentiate dysmyelination from demyelination.

Brain Diseases↗

Cerebral hemiatrophy caused by multiple developmental venous anomalies involving nearly the entire cerebral hemisphere.

The authors present a case of multiple developmental venous anomalies (DVAs) that involved nearly the entire cerebral hemisphere and that were diagnosed by magnetic resonance (MR) imaging and selective cerebral angiography. The ipsilateral cerebral hemisphere was mildly atrophic, and there were focal white matter lesions on the MR images. Angiography showed multiple DVAs involving nearly the entire right cerebral hemisphere. We suggest that longstanding venous congestion caused the atrophy and white matter lesions.

Atrophy↗

Persistent primitive olfactory artery: diagnosis with MR angiography.

We present a case of persistent primitive olfactory artery (PPOA) diagnosed with the aid of magnetic resonance (MR) angiography. The proximal right anterior cerebral artery (ACA) had an extremely long anteroinferomedial course along the ipsilateral olfactory tract, made a hairpin turn posterosuperiorly, and became a normal distal ACA. After reviewing the literature, we considered the proximal segment of this anomalous ACA to be a PPOA. To our knowledge, this is the first report of a patient with this anomalous ACA diagnosed with MR angiography.

Adolescent↗

Supraclinoid carotid dissection in a pediatric patient.

The authors present the case of a 13-year-old boy with a left temporal lobe infarction that developed during a 400-m run. Magnetic resonance (MR) angiography showed segmental narrowing of the left supraclinoid internal carotid artery (ICA) and a duplicated left middle cerebral artery (MCA). MR angiographic source images revealed a crescent-shaped left carotid lumen, indicative of a supraclinoid carotid dissection.

Adolescent↗

Rigid spine syndrome associated with cardiomyopathy: clinical and nosological considerations.

We report observations in a 32-year-old man with the following characteristics of rigid spine syndrome: humero-peroneal muscular atrophy and weakness; bradycardia, dilated cardiomegaly and complete cardiac conduction block; and severe fatty degeneration of the paravertebral and calf muscles. The latter showed a predominance of type 1 fibers, a deficiency of type 2A fibers, and an increase in type 2C fibers. The patient had no familial background of the disease. There was no contracture of the elbows. These findings, especially the severe cardiac involvement, suggest that the rigid spine syndrome can be difficult to distinguish from the Emery-Dreifuss form of muscular dystrophy.

Adult↗

Basilar artery fenestrations detected by MR angiography.

Basilar artery (BA) fenestrations are the most frequently observed fenestrations of the cerebral arteries. Our goal was to examine the magnetic resonance (MR) angiographic incidence, location, and characteristic configuration of BA fenestration. Between April 1996 and March 2000, 600 cranial MR angiographies were performed at our institution. The majority of the patients examined had or were suspected to have cerebrovascular disease. We retrospectively reviewed these 600 MR angiograms. A 1.5 Tesla scanner was used in all studies, and maximum intensity projection (MIP) images obtained using the three-dimensional time-of-flight (3D-TOF) technique were displayed stereoscopically. Ten BA fenestrations (1.7%) were detected on MR angiograms. In 87 cases from the early period, the vertebrobasilar (VB) junction was unfortunately not included in the imaging slices. Eight of the 10 fenestrations were located at the proximal BA: six of them were small with a slit-like shape, and two were relatively large with a convex-lens-like shape. A small fenestration was located at the distal BA, and the remaining one was a total duplication of the BA. We stress that knowledge and recognition of BA fenestration are useful and important in the interpretation of cranial MR angiography. Since saccular aneurysms are reported to arise frequently at BA fenestration, the VB junction should be included in the imaging slices of routine cranial MR angiography.

Basilar Artery↗

Systemic lupus erythematosus associated with marked intracranial calcification.

The authors describe a case of systemic lupus erythematosus associated with marked intracerebral calcification. The distribution of high signal on T1-weighted MR images was almost identical to the distribution of calcification on CT; however, the bodies of caudate nuclei with little calcification on CT also showed high intensities on T1-weighted images.

Adult↗

Definitive proton beam radiation therapy for inoperable gastric cancer: a report of two cases.

Proton beam radiation therapy using 250 MeV protons was carried out on two patients with early gastric cancer (T1, N0, M0). One patient was an 85-year-old man with early gastric cancer of type IIa + IIc. The other one was a 70 year old man with early gastric cancer of type IIc. In both cases histological examination of biopsy specimens showed differentiated adenocarcinoma; distant metastasis was not found by other examinations. Both patients were considered inoperable due to their poor cardiac and/or respiratory functions. Therefore, it was decided to treat them by definitive proton irradiation, delivering total doses of 86 Gy and 83 Gy, respectively. In both patients, skin erythema that did not require any special treatment was found in the irradiation field. Hematobiological examinations did not show any abnormality. Although endoscopic examination at two years after irradiation in the former case and at seven months in the latter case showed persistent gastric ulcer at the site of the cancerous lesions, cancer cells were not found histologically. Therefore, we concluded that proton irradiation therapy was useful for inoperable early gastric cancers.

Adenocarcinoma↗