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T Hoshida

Publications and source records attributed to T Hoshida.

36 records · Page 2Linked to original sources
PubMed1994

Reliability of amygdalohippocampal volume measured directly on MRI films.

Volume measurement of the amygdalohippocampus on MRI may provide important information for epilepsy surgery. This study investigated the reliability of direct volume assessment (DVA) versus computer-assisted measurement (CAM) of amygdalohippocampus. DVA was carried out by counting the number of squares occupied by amygdalohippocampus in a transparent mm2 overlay used on both sagittal and coronal films. CAM was achieved using the 'thresholding and tracing' automated technique. Seventeen patients undergoing language-dominant left temporal lobectomy were studied. Mean volume as determined by the CAM was 4.99 +/- 1.31. In DVA, the mean volume was 5.05 +/- 1.23 (r = 0.974). Reproducibility of the volume measurement was tested by repeating measurements 5 times on 5 patient samples of amygdalohippocampal complex in DVA, and 3 times on 4 samples in CAM. The mean coefficient of variation for amygdalohippocampal volume was 6.9 +/- 3.2% in DVA and 3.9 +/- 2.0 in CAM. We also tested a more simplified method of assessing amygdalohippocampal volume by calculating the left to right volume ratio from MRI scans (2-40 films for each sample). Volume ratios determined directly from MRI films made in different months (14 samples) and of different sections (coronal and sagittal series, 18 samples) correlated well with each other (p < 0.01). Direct assessment of amygdalohippocampal volume can be used effectively for preoperative evaluation of the patient with epilepsy.

Adult↗
PubMed1994

Experimental study of the mechanism of seizure induction: changes in the concentrations of excitatory amino acids in the epileptic focus of the cat amygdaloid kindling model.

L-glutamate (Glu) and L-aspartate (Asp) are two major excitatory amino acids that may be involved in seizure susceptibility and seizure induction. The concentrations of Glu and Asp were measured by microdialysis in the epileptic focus in a cat amygdaloid kindling model. Sequential changes in Glu and Asp (before, during, and after seizure) were measured in the partial seizure (S4) and generalized seizure (S6) groups. By stimulation at and 50 microA below the partial seizure-triggering threshold in the S4 group and the generalized seizure-triggering threshold in the S6 group, Glu was released from the epileptic focus in the S4 group, and both Glu and Asp were released in the S6 group after seizure and stimulation (below threshold), and the amount of Glu and/or Asp release determined seizure induction. Excitatory amino acids may be the trigger of seizure induction in the cat amygdaloid kindling model.

Amygdala↗
PubMed1994

Pleomorphic adenoma of the lacrimal gland manifesting as exophthalmos in adolescence--case report.

A 16-year-old girl presented with a pleomorphic adenoma of the lacrimal gland manifesting as left painless exophthalmos which had persisted for 3 years. Computed tomography revealed a tumor about 15 mm in diameter in the superolateral site of the left orbit. The tumor was removed completely by combined orbitofrontal craniotomy through a transcranial approach. Histological examination demonstrated the growth of tumor cells as glandular cavities or sheets, with myxoid and partly chondroid connective tissue stroma. Pleomorphic adenoma of the lacrimal gland is unusual in adolescents.

Adenoma, Pleomorphic↗
PubMed1994

Strategies to improve the outcome of carotid endarterectomy.

The outcomes of carotid endarterectomy (CEA) including long-term results in 121 patients (126 procedures) were retrospectively analyzed to identify the causes of operative morbidity. The angiographic internal carotid artery (ICA) stenosis was severe (> 70%) in 62 patients and moderate (50-70%) with ulceration in 64. The arterial wall was sutured primarily in 91 patients and with patch graft in 35. The outcomes 3 months after operation were good recovery in 86 patients, moderately disabled in 20, severely disabled in 11, and death in four. Three patients suffered operative morbidity (2.5%). During follow-up, three patients (2.6%) suffered transient ischemic attack on the operative side due to middle cerebral artery stenosis (50%) or ICA occlusion at the origin, and recurrent stenosis (40%) of the common carotid artery and ICA (1 each). In the latter two cases, the artery was primarily sutured. Improved therapeutic results require use of patch vein graft for the arterial wall suture, checking of the CEA patency, and prevention of intracranial ischemic events and hemorrhage due to associated lesions.

Adult↗
PubMed1993

[A characteristic magnetic resonance image of a dissecting aneurysm in the vertebrobasilar system].

Recently several reports of dissecting aneurysm in the vertebrobasilar system have been published. We report the effectiveness of MRI for the detection of a dissecting aneurysm in the vertebrobasilar distribution system. A 47 year-old male [correction of female] was admitted to our hospital due to right occipitalgia and the right Wallenberg's syndrome. Computed tomography disclosed no abnormalities. Cerebral angiogram showed the pearl and string sign of the right vertebral artery, which suggested a dissecting aneurysm. MRI exhibited the infarct area at the right dorsolateral part of the medulla oblongata, which corresponded to right Wallenberg's syndrome. It disclosed high intensity ring-like findings circumscribing a low intensity spot of the lumen of the right vertebral artery. This high intensity was thought to be the hematoma between the intima and the media at the subacute stage. Its high intensity corresponded to the site of the dissecting aneurysm and of Wallenberg's syndrome. These findings are thought to be useful in the diagnosis of a dissecting aneurysm of the vertebral artery.

Aortic Dissection↗
PubMed1993

[Experimental study of acute spinal cord injury: a histopathological study].

The microscopic appearance of a rat spinal cord which was acutely compressed by aneurysmal clip for one minute, was investigated 15 minutes, 30 minutes, 1 hour, 3 hours and 6 hours after the injury. Although the resulting small hemorrhagic lesion involved primarily only the central gray matter of the injured portion 15 minutes after compression injury, hemorrhage, necrosis and edema in the central gray matter enlarged progressively until 3 hours after injury. Petechial hemorrhage, necrosis and edema were observed in the surrounding area one hour after spinal compression. Then these pathological changes extended rostrally and caudally, but their extension was more significantly remarkable in the rostral side than in the caudal side 3 hours after compression. It was observed that leukocytes begin to infiltrate into the injured capillary walls and plug up the capillary lumen 30 minutes after the injury. Three hours following the injury, leukocytes (lymphocyte, macrophage) extravasated into the surrounding spinal tissue. From these histopathological observations, we reached the following conclusions. A. Secondary injuries play an important role in grave impairment of neurological function of the spinal cord following acute trauma. B. Pathological findings (hemorrhage necrosis and edema) extend more prominently to the rostral side, because the direction of spinal blood flow may be rostral in the thoracic spinal cord. C. Severe disturbance of intraspinal capillary blood flow leading to grave spinal damage may be evoked, because leukocytes infiltrate into the capillary around the injured area and plug up the their lumen about 30 minutes after the injury.

Acute Disease↗
PubMed1993

[Experimental study of acute spinal cord injury: a study of spinal blood flow].

It is well known that the worsening of neurological findings after spinal cord injury is due to the secondary progression of pathological changes which may be caused by spinal cord blood flow disturbance. We measured spinal blood flow of 5mm rostrally and caudally distant portions from the injured point, using the laser Doppler flowmeter experimentally. Forty rats were used. Ten of these were used as a control group. And thirty animals were injured at the level of the tenth thoracic cord with a 50g epidural one minute compression method and measured continuously from 30 minutes before the injury to 6 hours after the injury. Twenty two surviving animals were evaluated. In the control group, spinal blood flow was stable. But in the injured group, spinal blood flow dropped by 30.6 + 9.8% on the rostral side and 37.3 + 17.6% on the caudal side in comparison with the resting value soon after the injury. Although the flow improved to 89.3 + 11.1 and 71.3 + 17.8% respectively 15 minutes later, it dropped again gradually and reached 42.8 + 14.1 and 66.2 + 16.4% respectively 6 hours after the injury had been inflicted. Lastly, in the animals, carbon perfusion was performed through the left ventricle. The normal figured vasculature in the preparation of the injured and measured portion was calculated with a microcomputer imaging analyzer and compared with control groups. The number of the normal vessels was significantly more abundant on the caudal side than on the rostral side (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Isoflurane in the management of status epilepticus after surgery for lesion around the motor area.

When conventional treatment for status epilepticus fails, general anaesthesia is recommended. We present our experience with isoflurane, an inhalational anaesthetic, in the management of four patients with status epilepticus which occurred soon after surgery for motor area lesion. The seizures were controlled with relatively small concentrations of isoflurane. Hypotension, the only adverse effect of isoflurane, was managed easily with the use of dopamine in physiological saline. Although status epilepticus occurring soon after surgery is transient, it carries a risk of persistent brain damage if active treatment is not instituted promptly. Isoflurane general anaesthesia may be recommended to control it in the intensive neurosurgical care.

Adult↗
PubMed1992

Secretory meningioma with elevated serum carcinoembryonic antigen level.

We recently encountered a 68-year-old woman with right sphenoid wing meningioma of the secretory type accompanied by an elevated serum carcinoembryonic antigen level. This case was neuroradiologically characterized by marked brain edema. Histologically, the lesion was rated as having meningothelial components and was rich in blood vessels and pseudopsammoma bodies. Carcinoembryonic antigen, epithelial membrane antigen, keratin, and cytokeratin were immunohistochemically detected in the pseudopsammoma bodies and the cells producing these bodies.

Aged↗
PubMed1992

Immunohistochemical study of a newly defined oncofetal antigen (HGR-Ag) in tumors of the central nervous system.

The oncofetal antigen (HGR-Ag) in brain tumors was newly defined using the monoclonal antibody derived from tissue extracts of an anaplastic astrocytoma. The HGR-Ag was purified through sequential chromatography using diethylaminoethyl-Sephadex A-50 and Con-A Sepharose affinity columns. The latter method indicated that HGR-Ag is not a glycoprotein, and Western blot analysis indicated a molecular weight of 80-90 kd. Purified antigen was used to produce antibody. This new antibody, designated H1H2, was shown to be an immunoglobulin G1 by immunodiffusion assay. Histological/immunohistochemical studies using the H1H2 antibody on paraffin and frozen tissue sections showed HGR-Ag to be intracellular rather than membrane-associated. The immunoreactivity of H1H2 was highest in malignant astrocytomas, glioblastomas, and normal fetal brain tissue. Neurinomas and certain carcinomas of other organs showed lesser, variable reactivity to H1H2. The strength of the antigen-antibody binding was correlated with the degree of malignancy in human gliomas. H1H2 bound to fetal brain tissue and undifferentiated neural tumors, but not to normal adult brain tissue, so HGR-Ag is probably a fetal oncoantigen.

Animals↗
PubMed1992

Anaplastic astrocytoma of an oncocytic type occurring in the cerebellar vermis in Pierre Robin syndrome--case report.

A 44-year-old male with Pierre Robin syndrome and funnel chest was diagnosed with a tumor of the cerebellar vermis and spontaneous pneumothorax. He received tube thoracostomy for pneumothorax and ventriculoperitoneal shunt for hydrocephalus, followed by radiological examination, subtotal removal of the tumor, pneumonorrhaphy, and chemoradiotherapy. Light microscopy of the tumor sample revealed marked pleomorphism of the tumor cells and numerous giant cells, without mitotic figures. Microcystic changes due to vasogenic edema were also evident throughout the tumor. Electron microscopy showed more than 50% of all tumor cells to be oncocytes, with numerous mitochondria in the cytoplasm. The tumor was diagnosed as anaplastic astrocytoma of an oncocytic type.

Adult↗
PubMed1991

Partial corpus callosotomy beneficial for Lennox-Gastaut syndrome--report of two cases.

Seizures in patients with Lennox-Gastaut syndrome are very resistant to drug therapy. Division of the anterior half of the corpus callosum was performed in two patients with Lennox-Gastaut syndrome incapacitated by frequent atonic seizures leading to sudden falls. Postoperatively, the atonic seizures were completely eliminated and their mental reactivities remarkably improved. It is clear that they have benefited from a lower frequency of seizures and reduced dosages of anticonvulsant medication, which outweight the acquired disabilities.

Adult↗
PubMed1991

Spontaneous intracerebral hemorrhage in cases of severe angiospasm following ruptured aneurysm--a pathological study.

Eleven patients with a history of moderate or severe angiospasm following ruptured cerebral aneurysm developed spontaneous intracerebral hemorrhage between 31 and 111 months after aneurysm surgery. In all cases, hemorrhage occurred in the ipsilateral hemisphere to the original aneurysm. In nine patients, the hematoma was surgically evacuated and bleeding perforating arteries were resected for histological examination. Computed tomographic scans showed the hematomas to be unusually extended compared to those after hypertensive intracerebral hemorrhage. The histological examination showed various degenerative changes in the elastic lamina and media of the perforating arteries, even though most patients were young and normotensive. These findings suggest that patients who have suffered severe cerebral angiospasm may have a higher risk for subsequent development of intracerebral hemorrhage than those without prior angiospasm.

Aged↗
PubMed1991

The effect of prostaglandin E1 on local cerebral blood flow during cerebral-aneurysm clip ligation.

Prostaglandin E1(PGE1) was administered for deliberate hypotension during general anaesthesia in 27 patients undergoing cerebral-aneurysm clip ligation, and the effect of the drug on local cerebral blood flow was studied. Local cerebral blood flow measurements were made using a thermal-gradient blood flowmeter. Control measurements were made immediately before administration of the drug. Local cerebral blood flow was measured 10, 30, 60 and 120 min after starting the drug infusion and 10, 30 and 60 min after discontinuation. The mean blood pressure was reduced significantly by the administration of PGE1. Urine output was increased after commencement of the drug infusion. Local cerebral blood flow did not change. These results suggest that PGE1 may be an appropriate hypotensive drug for use during cerebral-aneurysm clip ligation, because the cerebral blood flow remains within the normal range and the urine output is increased.

Alprostadil↗
PubMed1983

[Value of contrast-enhanced CT scan in prediction of development of contusional hemorrhage].

It is often experienced that even if there are no significant findings on the initial plain CT scan in the patient with cerebral contusion, the patient has thereafter a serious clinical course and requires emergency operation for so-called contusional hemorrhage. In order to predict of the development of contusional hemorrhage we performed contrast-enhanced CT scan at the time of patient's arrival within 12 hours after injury, if there was cerebral contusion on 24 hours after the contrast-enhanced CT scan. If enhancement was demonstrated on the contrast-enhanced CT scan, we predicted the development of contusional hemorrhage and if not demonstrated, we predicted no more development of contusional hemorrhage and then we studied the correlation between the prediction and the plain CT 24 hours after the contrast-enhanced CT scan. The results were as follows: 1) The prediction was correct in 13 cases out of 16 cases in which the development of contusional hemorrhage was observed. In 18 cases where no development of contusional hemorrhage was observed, the prediction was correct without exception. 2) Most of the cases in which enhancement was demonstrated were ones examined not before 3 hours after injury. 3) The extent of enhancement shown on contrast-enhanced CT scan was well consistent with that of contusional hemorrhage on the plain CT scan 24 hours after the contrast-enhanced CT scan. From these results, the contrast-enhanced CT scan in acute stage of head injury was considered to by very useful in prediction of the development of contusional hemorrhage.

Adolescent↗
PubMed1983

[Multiple meningioma].

Meningiomas are the most popular benign intracranial tumors, but they are rarely seen as a multiple growth. The incidence of multiple meningiomas, defined by Cushing and Eisenhardt, is about 1 to 2 per cent of all meningioma cases. Though many cases of the multiple meningiomas were reported previously in the world, some of them were concomitant with von Recklinghausen's disease or acoustic neurinoma. Most of the cases of the multiple meningiomas reported showed multiple lesion at the time of operation or after a few years of the initial operation. We have encountered two patients with multiple meningioma without the stigmata of von Recklinghausen's disease in our clinic. Case 1. A 58-year-old female visited the hospital complaining of headache and occasional nausea on February 6, 1980. Plain and enhanced cT confirmed a large tumor in the right parietal region and three small tumor nodules in the right occipital region. Carotid angiogram detected only two tumors of frontal falx. Apparent two tumor stains were seen on the region, and they were fed by meningeal frontal and parietal region, and they were fed by meningeal arteries through the right ophthalmic artery. A large tumor of parietal and a small tumor of frontal region on the right side of falx were removed. Three nodular tumors of right occipital convexity were extirpated at the same time. Histological examination of the tumors disclosed all extirpated tumors were fibroblastic meningioma. Case 2. A 61-year-old male developed convulsive seizure of the right upper limb and right side of the face was diagnosed as having convexity meningioma in the left parietal region.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗