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S Kurosaki

Publications and source records attributed to S Kurosaki.

12 recordsLinked to original sources

Three-component analysis of caloric nystagmus in humans.

Three-component analysis of caloric nystagmus, focusing on the horizontal, vertical, and torsional, using a computerized eye movement analysis system, was carried out in 10 normal human subjects. The caloric response was induced by cold stimulation to the right ear of the subjects in the supine and prone positions. In the supine position, the three components of nystagmus were toward the left (10 subjects), upward (eight subjects) or downward (two subjects), and clockwise (10 subjects). In the prone position, on the other hand, the three components were directed toward the right (10 subjects), downward (five subjects), upward (three subjects), and counterclockwise (10 subjects); there was no vertical direction in two subjects. These findings indicate that caloric stimulation activates the three semicircular canals simultaneously. Also the changes in the nystagmus direction in the supine and prone positions could be explained, at least partially, by the nonconvective component of caloric stimulation.

Adult

[Three dimensional analysis of caloric nystagmus using computerized image recognition].

Three-component analysis of caloric nystagmus, focusing on horizontal, vertical, and torsional directions, using a newly developed computerized eye movement analysis system was carried out in ten normal human subjects. The caloric response was induced by cold stimulation to the right ear while the subjects were in supine and prone positions. The directions of the three components of nystagmus, were left in ten subjects (10), upward (8) or downward (2), and clockwise (10) in the supine position. In the prone position, on the other hand, the three components were directed toward the right (10), downward (5), upward (3), and counterclockwise (10) or were not present (2). These findings indicate that caloric stimulation activates the three semicircular canals simultaneously. In addition the changes in the direction of nystagmus in the supine and prone positions could not be explained in detail by the convection theory of caloric response alone.

Adult

[Anaplastic astrocytoma 14 years after radiotherapy for pituitary adenoma].

A case of anaplastic astrocytoma following radiotherapy for growth hormone secreting pituitary adenoma is presented with a review of the literature. A 43 year old female was admitted with the signs of acromegaly and hypertension. An eosinophilic pituitary adenoma was subtotally removed by transsphenoidal approach, and followed by 60 Gy irradiation using a 2 x 2 cm lateral opposed field. Fourteen years later at the age of 57, she suffered from headache, recent-memory disturbance and uncinate fits. CT scan and MRI disclosed ring-like enhanced mass lesion in the left temporal lobe, corresponding to the previous irradiated field. 18F-FDG PET showed hypermetabolism at the lesion. Left frontotemporal craniotomy was performed, and a reddish gray gelatinous tumor containing necrotic center and cyst was partially removed. Histologically, the tumor consisted of hypercellular astrocytic cells with perivascular pseudorosette. Coagulation necrosis at the center of the tumor, and hyalinosis and fibrosis of the blood vessels in and around the tumor, which might have been caused by the antecedent radiotherapy, were recognized. Postoperative radio- and chemotherapy were given, however, she expired 13 months after the operation. Seven cases, including ours, of malignant glioma following radiotherapy for pituitary adenoma were reported in the literature. A total dose of irradiation varies from 45 to 95 Gy with a mean of 50 Gy. The period of latency before tumor occurrence ranges from 5 to 22 years with a mean of 10 years. The differentiation of radiation-induced gliomas from radionecrosis of the brain is also discussed.

Adenoma