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T Tsubokawa

Publications and source records attributed to T Tsubokawa.

At least 217 records · Page 12Linked to original sources
PubMed1978

[A case of giant aneurysm at the posterior cerebral artery (author's transl)].

Giant aneurysm of the posterior cerebral artery was very rare. The authors could seek only 6 cases in published literature. We experienced one case of the giant aneurysm at the posterior cerebral artery. The case was 25 years old female. She occasionaly complained of headache and nausea for 4 years before administration. Cerebral angiogram revealed a giant aneurysm of the right posterior cerebral artery with slightly dilated ventricle. CT scan revealed a ring shape high density area and its high density area enhanced by Conray infusion. A clipping of posterior cerebral artery at the just proximal point of the aneurysmal neck was done, because adhesion of the aneurysm to the brain stem was very tight and the aneurysmal neck was very broad. After the operation, giant aneurysm was not seen on both angiogram and CT scan. Patient did not complain of headache any more and any defect of the visual field.

Adult↗
PubMed1977

[Modulating mechanism of the dorsal column stimulation for pain relief (author's transl)].

The neural mechanism of the modulating effects of spinal cord stimulation upon intractable pain was studied in cats under local anaesthesia. The electrical activity at the centre median nucleus of the thalamus (CEM), which responded to noxious stimuli and was inhibited by nitrous oxide inhalation, was recorded as an indicator of the degree of pain sensation. The suppressed effect upon the evoked potential responding to sciatic stimulation (1 Hz) was recorded during and after train stimulation of various parts of the spinal cord by means of silver ball bipolar electrode. Whenever inhibitory modulating effect upon CEM response was observed by spinal cord stimulation, the bilateral dorsal tractotomy cranial, caudal or both to the stimulating point in order to examine the influence upon the CEM potential. The results are as follows: 1) The CEM evoked potential responding to sciatic stimulation is inhibited by about 30-45% of its amplitude by dorsal column stimulation. This effect corresponds to the inhibitory effect by 75% N2O gas inhalation. Upon dorsal column stimulation, the intraspinal electrical activity is found in the central gray matter the antero-lateral quandrants of the spinal cord as well as the dorsal column. 2) Following lateral or anterior column stimulation as well as dorsal column stimulation, the CEM evoked potential responding to sciatic stimulation is inhibited by about 50% of its amplitude. 3) Following bilateral dorsal tractotomy cranial, caudal or both to the stimulating point, the CEM evoked potentials responding to sciatic stimulation are inhibited by dorsal column stimulation. According to the experimental results, it may be concluded that the inhibitory modulating mechanism by dorsal column stimulation for pain relief is not only mediated through the dorsal column, but also through other ascending spinal pathways.

Animals↗
PubMed1976

[A new modified wick catheter for measurement of the brain tissue pressure-an evaluation of static and dynamic properties of the catheter (author's transl)].

The interstitial pressure of the brain was measured with wick catheter by Lassen in 1972. But original wick catheter inserted into the brain tissue does not always measure the real interstitial pressure as indicated by experimental results of Brodersen, because, the interstitial pressure is always affected by solid pressure such as cells in the brain tissue, in the condition of which surrounded by positive CSF pressure in the semiclosed skull box. It is not yet clarified what kinds of the pressure are measured by wick catheter method in the brain tissue. The size of wick catheter is 300-500 times as large as the width of interspace of the brain tissue and the catheter is easily obstructed by brain tissue. Therefore, a new, modified wick catheter is made for improvement of these problems which is observed by using original wick catheter. The new, modified catheter has 0.4 mm inside diameter and 10 cm length. The tip of catheter is closed and 6 small side holes(0.1 mm0)are made. Inside the catheter, several pieces of 0.04 mm diameter nylon threads are inserted as shown in figure 1, and the catheter is filled up with the cerebrospinal fluid. In this paper, the structure of the new, modified catheter is demonstrated, and the brain tissue pressure is measured, comparing with the results of the original wick catheter to test the function of the new, modified catheter. The results of measurement of the brain tissue fluid pressure with the new, modified catheter are as follows; 1) The brain tissue fluid pressure is relatively constant and shows a positive pressure of 5.2 mmHg. 2) As there are few blocking effects in the catheter, the new, modified catheter is useful for the measurement of the brain tissue fluid pressure for a long time. 3) The brain tissue fluid pressure is not altered by the number's of nylon threads in the catheter at static condition, but movement of brain tissue fluid pressure with respiration is a little dumped by the increased conductancy with the numbers of nylon threads in the catheter. 4) The tissue fluid pressure affected by the viscosity and osmolarity of the fluid in the catheter, CSF should be used for correct measurement. According to these results, it might be concluded that the new, modified wick catheter is better than the original wick catheter regarding prevention of obstruction of the catheter by brain tissue fragments, artifacts which causet by movement of wick fibers, measurement of brain tissue fluid pressure for a long time and clarify the resistance of catheter to pressure conductancy.

Animals↗
PubMed1975

The sarcoma arising in giloblastoma: clinico-pathological report of two cases.

Two cases of primary brain tumor composed of an admixture of sarcomatous and gliomatous tissues are reported together with their clinical courses and neurosurgical examination. There is no difference in clinical course nor in the result of examination between the usual glioblastoma multiforme and these admixture tumor. The histological examination at the surgical biopsy and autopsy suggested that enoplastic change of the sarcomatous element occurs markedly on hyperplastic blood vessels in the glioblastoma multiforme. The neoplastic change observed on hyperplastic blood vessels is not affected by radiation therapy.

Brain Neoplasms↗
PubMed1975

[Treatment for traumatic aneurysm of the cerebral artery--identification between deteriorating type and spontaneously disappearing type (author's transl)].

Thirty five cases of traumatic aneurysm of the cortical cerebral artery were reviewed in the literatures cited in the references. Five cases of them healed spontaneously without operative treatment (disappearing type), the other cases underwent direct operation of aneurysm, in spite of high operative moltality or mobility (deteriorating type). Recently four cases of traumatic aneurysm of the cortical cerebral artery were treated in our clinic. Three cases which had the aneurysm in the pericallosal artery (1 case) and middle cerebral artery (2 cases) respectively underwent radical operation for treatment as progressively deteriorating type and fourth case which had the aneurysm in the peripheral part of the frontopolar artery was treated by medication as the spontaneously disappearing type until the aneurysm disappeared on the angiogram. According to the review of literatures, it is the most important for the treatment of tramatic aneurysm to know whether disappearing type or deteriorating type, because deteriorating type had bad prognosis without radical operation and the prognosis of disappearing type was excellent without operation. Analysing the clinical signs and angiographical findings of the all cases, the authors found out some specific characteristics of the spontaneously disappearing type. are (1) The aneurysm is found in the relativery late post traumatic stage except for cases caused by penetrating wound, (2) The irregular shape, uneven opacity of the aneurysm without clear neck connecting with pearent artery on angiography, (3) Shape and size of the aneurysm in follow up angiogram (two weeks or more) became smaller, (4) Around of aneurysm, there are not any kind of intracranical hemetoma. According to these results, differential diagnosis between spontaneously disappearing type and deteriorating type was done in the author's four cases and the three cases of deteriorating type were relieved by radical operation without any postoperative disability and one case of spontaneously disappearing type was treated by medical treatment until disappear of aneurysm. It is concluded that traumatic aneurysm of the cortical cerebral artery is relative rare and it is important to know whether deteriorating type or spontaneously disappearing type in order to get excellent results.

Adolescent↗