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Biomedical subjects

U Ito

Publications and source records attributed to U Ito.

At least 55 records · Page 3Linked to original sources
PubMed1987

[Melanosis of choroid plexus papilloma of the lateral ventricle: a case report].

A case of pigmented, well differentiated, choroid plexus papilloma is reported. A 45-year-old man came to our hospital complaining of attacks of vertigo and nausea. Skull X-ray films and CT scan demonstrated a calcified tumor in the left middle fossa. Tumor removal was done, and it was found that the tumor occupied the inferior horn of the left lateral ventricle. Histological examination revealed well differentiated choroid plexus papilloma containing various shaped pigment granules in the cytoplasm. The pigment granules in the tumor cells were stained black by Fontana-Masson method for melanin. The stain was negative in a section subjected to oxidative bleach. Granules were PAS-positive and autofluorescence. Therefore, the pigment granules had properties of both melanin and lipofuscin. In the electron microscopic study the ultrastructural appearance of the pigment was similar to that of neuromelanin, but not to that of pre-melanosome of neural crest origin. The pigment in this case seemed to be formed by "melanization" of lipofuscin as Barden's theory of pseudo-peroxidation. There are several case reports of pigmented choroid plexus carcinoma. However, no case of pigmented, well differentiated choroid plexus papilloma has, so far, been reported.

Cerebral Ventricle Neoplasms↗
PubMed1986

Brain swelling and brain oedema in acute head injury.

Chronological changes in diffuse brain swelling and brain oedema were studied in repeated CT studies following a closed head injury. These findings were compared with changes in intracranial pressure (ICP). The grades of diffuse brain swelling were classified into mild, moderate and marked according to the CT findings. Planimetry of low density areas of brain oedema was carried out on repeated CT images. Diffuse brain swelling was recognized in 71% of patients shortly after the head injury and subsided within days 3-5. Brain oedema first appeared 24 hours post injury and did not reach its maximum size and distribution before days 5-8. Thus, these two events can be clearly separated. The intracranial pressure reflected the course of the brain swelling and was not very high during the presence of maximum oedema.

Acute Disease↗
PubMed1986

Spatial and quantitative distribution of human peritumoural brain oedema in computerized tomography.

Computerized tomography (CT) was used to study the pathways of oedema spreading in man. Based on the assumption that local changes in CT numbers in oedematous white matter closely correspond to changes in tissue water content, CT numbers of consecutive tissue blocks of 3.0-3.6 mm were examined in the main directions of oedema spreading: towards the deep white matter, towards the cortex and towards the ventricle. Tumours with oedema grade II and III showed a reduction of CT number of 10 +/- 1.8. The corresponding increase in water content of about 10-12% seems to be an upper limit of fluid accumulation in the white matter. From this oedema centre, water content very slowly and gradually decreased along the oedema projection into the deep white matter. In contrast, if oedema reached the cortex of adjacent gyri, the decline in water content was very sharp. A similar observation was made in the external capsule where oedema sharply declined at the border to the adjacent grey matter, putamen and claustrum. Oedema projection towards the ventricle showed a nearly uniform magnitude from the centre to the ventricular lining, suggesting a certain resistance by a limited capacity of transependymal drainage of oedema fluid. It is assumed that the spatial distribution and extension of oedema around a brain tumour is determined by a system of differential resistance to fluid movement in the following order: grey matter--ventricular lining--white matter.

Brain Edema↗
PubMed1986

Enhanced cisternal drainage and cerebral vasospasm in early aneurysm surgery.

Enhanced cisternal drainage was performed following early aneurysm surgery in patients with Hunt and Kosnik grades I-III, to effect continuous wash-out of subarachnoid blood clots and reduce symptomatic vasospasm. Following extensive evacuation of the cisternal blood clots, the Liliequist's membrane was opened extensively and a third ventriculostomy was effected by opening the lamina terminals. The drainage effect was considered as poor, moderate or fair, depending on the average amount of CSF drainage/day. SAH was graded into 0-III depending on the severity of cisternal haematoma in the pre-operative CT. No symptomatic vasospasm occurred in patients with SAH grade I. In SAH grade II + III patients symptomatic vasospasm occurred in 78, 60 and 42% of patients with a poor, moderate and fair drainage effect, respectively. Nine patients who developed symptomatic vasospasm were treated by hypertensive/hypervolemic therapy (HHT). The HHT was effective in 7 patients with fair and moderate CSF drainage and ineffective in 2 patients with poor a drainage effect. It seems, that enhanced post-operative cisternal drainage can reduce the incidence of symptomatic vasospasm and be of benefit to the outcome of early aneurysm surgery.

Blood Pressure↗
PubMed1986

CT findings of leptomeningeal and periventricular dissemination of tumors. Report of four cases.

Four cases of leptomeningeal dissemination of tumors were reported especially focused on their CT findings. These findings consisted of hydrocephalus and contrast enhancement of the quadrigeminal cistern, basal cisterns, Sylvian fissures, cerebro-cerebellar cortical sulci and ventricular wall. Although autopsy of 3 cases revealed diffuse subarachnoid tumor growth in the brain and spinal cord, not all lesions were demonstrated by CT. Therefore, CT findings varied greatly depending on case and course of the disease. Definite diagnosis of this disease could be done by CSF cytology.

Adenocarcinoma↗
PubMed1986

[A mechanism of development and resolution of vasogenic brain edema].

To investigate the mechanism of development and resolution of vasogenic brain edema, authors have infused the mock CSF containing 35S-sodium thio-sulfate via a thin needle into the white matter of either normal cat's brain or into the edematous brain. The animals which were used in these experiments were divided into four groups (L20, L45, C20, C45). In the groups of animals subjected to a cold lesion (L20, L45), a small craniotomy was performed over the right frontal pole. A cold injury edema was produced 24 hours prior to the experiment. Na-Fluorescein (2 ml/kg) was given intravenously just prior to the cold lesion to later visualize the extent of the edema. For the positioning of the four needles in the brain, the coordinates were used according to the Horsley-Clark method and the atlas of Reinoso-Suarez. The location of tissue infusion (TIP) corresponds to a point approximately 3.0 mm before the frontal apex of the right lateral ventricle. The infused artificial CSF was mixed with 35S sodium-thiosulfate and stained with Evans Blue to check the extent of propagation of the infused solution. This solution was infused into the tissue at the point TIP with a rate of 0.20 ml/hr in groups C20 and L20 and 0.45 ml/hr in groups C45 and L45. Both lateral ventricles and cisterna magna were cannulated, and a ventriculo-cisternal perfusion with an artificial CSF was established through the right lateral ventricle with a perfusor. The perfusion rate was 2.25 ml/hr. The cisternal outflow was collected during every 15 min. for the activity and volume measurement. Tissue water content was determined by the drying method.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Computer-analyzed EEG before and after bypass surgery. Quantification by a computerized wave form recognition method.

Chronological changes of the EEG before and after extracranial-intracranial arterial bypass surgery were studied on 12 patients with minor completed stroke of the carotid circulation. Instead of a power spectrum used in the conventional computer analysis, a wave form recognition method, which well correlated with visual assessment of the EEG, was applied to the present computer analysis of the EEG. The EEG changed mainly in the parietal, occipital, anterior and middle temporal records of the affected cerebral hemisphere. Deterioration of the EEG continued until 1 month, and improved gradually during 3 and 6 months after the operation. However, it was difficult to conclude that the EEG improved by surgery.

Adult↗
PubMed1984

Regional cerebral blood flow and stroke index after left carotid artery ligation in the conscious gerbil.

We measured the regional cerebral blood flow in both hemispheres of Mongolian gerbils subjected to permanent left carotid artery ligation, using [3H]nicotine as the tracer. At 1, 3 and 6 h post-ligation, neurological signs were recorded and a stroke index score was tallied for each animal. In conscious control gerbils, mean cerebral blood flow on the left side was 1.10 +/- 0.08 (S.E.M.) ml X g-1 X min-1 at the cerebral cortex, 0.58 +/- 0.02 at the hippocampus and 0.69 +/- 0.04 at the diencephalon. Animals with a stroke index score exceeding 10 were considered symptomatic. We noted a close relationship between regional cerebral blood flow and the stroke index score. In symptomatic animals, regional cerebral blood flow in the ischemic hemisphere at 1, 3 and 6 h post-ligation was less than 0.21 ml X g-1 X min-1 at the cortex and diencephalon, and less than 0.09 ml X g-1 X min-1 at the hippocampus. We suggest that unilaterally ligated gerbils manifesting a stroke index score greater than 10 represent a good experimental model for the study of ischemia.

Animals↗
PubMed1979

Cerebrospinal fluid cytology after subarachnoid hemorrhage.

A method is described which has been found capable of detecting subarachnoid hemorrhage (SAH) up to 15 to 17 weeks after its occurrence. The episode of SAH was confirmed by bloody and/or xanthochromic cerebrospinal fluid (CSF) at the time of SAH onset. In this study, 47 samples of lumbar CSF from diagnostically confirmed SAH patients were used. The CSF cells were collected onto slides and stained with May-Gruenwald-Giemsa or Perl's reagent. Iron-positive cells were detected at 1 week, increased by 4 to 6 weeks to 8.5% of total nucleated cells, and decreased to 1% by 15 to 17 weeks. All 27 samples obtained at 2 to 9 weeks after SAH showed iron-positive cells. No iron-positive cells (false-negative samples) were noted in 25% (one of four) of samples obtained during the first week, and in 33% (one of three) of samples obtained 10 to 12 weeks and 15 to 17 weeks after SAH. Of the total samples (37) obtained within 17 weeks after SAH, 8.1% (three of 37) were false negative. No iron-positive cells were detected in samples obtained later than 21 weeks after the SAH episode (10 samples).

Cerebrospinal Fluid↗