Biomedical subjects
Publications and source records attributed to K Kyoi.
This report describes a case of traumatic carotid-carvernous fistula which presented as an intracerebral hemorrhage. The usual ocular signs were absent due to an atypical drainage pattern from the cavernous sinus. Engorgement of the deep venous system of the brain due to the carotid-cavernous fistula was thought to have caused the intracerebral hemorrhage.
Immunohistochemical studies using immunoperoxidase staining for glial fibrillary acidic protein (GFAP), S-100 protein, and factor VIII-related antigen (VIII-RAg) were performed on 10 hemangioblastomas of the central nervous system to determine the origin of stromal cells. No cytoplasmic immunoreactivity for anti-GFAP, anti-S-100 protein, or anti-VIII-RAg was detected in most stromal cells. A small number of GFAP-positive cells were found only in the periphery of the tumor; they were thought to be trapped astrocytes or stromal cells taking up GFAP. Most stromal cells had abundant, clear cytoplasm with some microfilaments and lipid vacuoles. Cylindrical cytoplasmic processes and intermediate junctions were observed in some stromal cells, but most cells did not possess any junctional device. No stromal cell possessed any feature clearly suggesting endothelial cells or pericytes. Our immunohistochemical and ultrastructural investigations did not support the theories of stromal cell origin from astrocytes or endothelial cells. We concluded that stromal cells can be regarded as an aberrant cell type of angiogenic mesenchymal derivation.
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Although it is well known that Wallenberg's syndrome is caused by occlusion of the vertebral artery (VA) or the posterior inferior cerebellar artery (PICA), the etiology of the occlusion is rarely documented. During the course of Wallenberg's syndrome, patients often complain of headache. We thought that these headaches might be caused by dissecting aneurysm (DA) of the vertebral artery, and so we studied the incidence of DA in our cases with Wallenberg's syndrome. Although many variants exist, Wallenberg's syndrome encompasses several neurological symptoms due to a disorder of the nucleus and nerve tracts located in the lateral part of the medulla. We diagnosed our patients as having Wallenberg's syndrome on the basis of symptoms such as loss of pain and temperature sensation in the unilateral face and contralateral body, cerebellar ataxia, and dysphasia. We investigated 22 cases of Wallenberg's syndrome over a five-year period, and excluded patients who developed subarachnoid hemorrhage upon onset of the syndrome. Our cases can be divided into two groups; one with severe stenosis or occlusion of VA (n = 15) and the other with occlusion of PICA (n = 5). The angiograms of the two remaining patients showed no abnormal findings. The mean age of the VA group (42.5 yrs.) was younger than that of the PICA group (64.2 yrs.). The age distribution of the PICA group is similar to that of other occlusive cerebrovascular diseases. Seven cases of the VA group demonstrated aneurysmal dilatation and luminal stenosis, and so they were diagnosed as having dissecting aneurysm of VA.(ABSTRACT TRUNCATED AT 250 WORDS)
A rare case of achondroplasia showing diffuse spinal canal stenosis is presented. A 39-year-old woman was admitted to our hospital because of numbness of lower extremities and intermittent claudication. The patient's height was 121cm and she had the typical clinical features of an achondroplastic dwarf. Neurological examination revealed spastic paraparesis, and sensory impairment below the level of T11 in the left side and L1 in the right. A plain X-ray feature of the spine showed spinal canal stenosis. The interpedicular distances were short in all vertebrae, and especially more prominent in the caudal lumbar region. The sacrum laid horizontally and the sacral angle was narrower than normal case. Myelography and computed tomographic myelography demonstrated severe stenosis of the subarachnoid space at the level of T9-11. Laminectomy was performed from the inferior half of T9 to T11. The yellow ligaments were prominently hypertrophic and these were removed as far as possible. Postoperatively, the weakness of the lower extremities was improved immediately, but numbness remained. Five months after the operation, she suffered from urinary dysfunction, so further laminectomy from T12 to L5 was performed. Also in this operation, hypertrophic yellow ligament was pathognomonic. Following this operation the patient had a good recovery course and returned to work.
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Cerebral vasospasm is a major complication associated with subarachnoid hemorrhage. In spite of extensive research, the pathogenesis of vasospasm remains obscure, and clinical management has so far been extremely difficult. For the evaluation of the efficacy of any treatment and the timing of operation, the development and resolution of the arterial narrowing should be monitored. It is important to know the correlation between the change in flow velocity and the course of clinical symptoms. In this study, the blood flow velocity in the different arteries was measured at short intervals (at least every third day) with transcranial Doppler ultrasonography, in eighteen patients with ruptured cerebral aneurysm. Flow velocity changes began to accelerate from 3 days after surgery, and reached the maximum value between 7 and 10 days, with normalization occurring within the following 2 weeks. The changes showed a significant relationship to the severity of vasospasm, the side of the operative approach, and the administration of calcium antagonist. Based on our results, we categorized the flow velocity changes of vasospasm for clinical practice as follows. (1) A slight acceleration of up to 120 cm/s in MCA and 90 cm/s in ACA was defined as within the normal range. In this state vasospasm was never observed angiographically. (2) Flow velocity changes between 120 and 140 cm/s were a subcritical state. These changes were seen in vasospastic patients who did not develop ischemic deficits. (3) Flow velocity changes of over 140 cm/s in MCA and 100 cm/s in ACA were critical vasospasm, since all of the patients who developed ischemic symptoms were in this group. Velocity changes higher than 170 cm/s in MCA and 130 cm/s in ACA seem to indicate a critical condition with a tendency to develop into brain infarction. The comparison between the time course of the flow velocity changes and clinical status showed that in symptomatic vasospasm the increase in velocity occurred before the manifestation of clinical symptoms. The transcranial Doppler measurements help to identify those patients who have a high risk of developing neurological deficits due to vasospasm, and help to select those who would benefit from preventive treatment in asymptomatic stage.
A rare case of ectopic meningioma of the ethmoid sinus is reported. A 57 year-old male patient was admitted with complaints of anosmia and headache. Computed tomography revealed a relatively high-density mass in the bilateral ethmoid and sphenoid sinuses. The mass was markedly enhanced after intravenous administration of contrast medium. The cerebral angiography showed tumor stains fed by bilateral internal and external carotid arteries with right side dominance. The tumor in the ethmoidal sinus was removed by otolaryngologists at first and then the tumor in the sphenoid sinus was removed using sublabial transseptal sphenotomy. The histological examination resulted in a diagnosis of transitional meningioma with psammoma bodies. The tumor in this case is suspected to have originated from heterotopic meningocytes or meningocytes accompanying the perineural sheath of the olfactory nerve.
The first case was a 5-year-old girl treated with a total of 6000 rads after total removal of a left temporoparietal tumor extending into the basal ganglia. About 4 years after completion of the radiation therapy, she showed left hemiplegia and deterioration in her level of consciousness. A plain CT scan showed calcification in the region of the bilateral basal ganglia and low density area in the right fronto-parietal region. An enhanced CT revealed gyral enhancements in the pre- and postcentral gyrus of the right hemisphere. Left carotid angiograms showed a narrowing of the horizontal portion and an occlusion of the distal portion of the left anterior cerebral artery. The distal portion of the right anterior cerebral artery was filled through the anterior communicating artery. Right carotid angiograms revealed an occlusion of the terminal portion of the internal carotid artery, retrograde filling of the anterior and middle cerebral arteries by leptomeningeal anastomosis via the posterior cerebral artery, and partial filling of the anterior cerebral artery via the anterior falx artery. Preoperative arteriography did not show occlusion and stenosis of the cerebral arteries. Superficial temporal artery-middle cerebral artery anastomosis in the right hemisphere was performed. Regional cerebral blood flow measured during operation increased from 34 to 72 ml/100 gr/min due to the surgery. About two weeks after surgery, left hemiplegia disappeared completely. The second case was a 67-year-old man who had received radiotherapy, following surgery of a chromophobe pituitary adenoma. About one year after irradiation he began to complain of gait disturbance and dysarthria.(ABSTRACT TRUNCATED AT 250 WORDS)
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The effect of the laser energy to the cerebral vascular reactivity and the blood brain barrier. A Nd:YAG laser with 20 watt impacts of 0.5, 1.0, 2.5 and 5.0 seconds duration time were irradiated through the cranial window made at the parietal regions of anesthetized adult cats. The disruption of the blood brain barrier was examined by checking the degree of the extravasation of Evans blue dye administrated in the vein. The cortical vessel reactivity was observed through the cranial window and evaluated using an intravital microscope and a videoangiometer. The extravasation of Evans blue dye was seen uniformly extending from the histologically changed area into the surrounding tissue in all experiments. The extent of the extravasation of dye was 1 to 1.5 mm larger than the extent of the histologically changed area produced by laser irradiation. Pial arteries in the area with histological changes dilated markedly and some of them lost their blood stream. Pial arteries in the area of Evans blue extravasation, but outside it histological changes also dilated markedly. Furthermore, pial arteries within a distance of 200 to 400 microns from the edge of the Evans blue extravasation area also dilated moderately. A statistical estimation showed that the degree of dilatation of arteries in the area outside the histological change improved significantly in the time course of five minutes.
Two cases of internal carotid aneurysms, trapped and bypassed, by means of radial artery grafts are discussed. Neither case has permanent neurological deficit possibly because of an adequate blood supply via the radial artery graft bypass. Although the radial artery graft has been in common use among cardiac surgeons, it is still rare in the neurosurgical field. The advantage of the radial artery is discussed with comparison to other graft materials such as the saphenous vein and the superficial temporal artery. In properly selected cases, the radial artery graft is useful in preventing the ischemic damage caused by an aneurysm being trapped at the main arterial trunk.
Craniocerebral CT scans were performed on 50 subjects including embryos, fetuses and newborns. Fetuses were divided into three stages based upon CT findings. The first stage ranged from the 8th gestational week to the 12th week, and the second stage from the 13th to 23rd week. Beyond 24 gestational weeks, fetuses were classified as the third stage. In the first stage, it is difficult to recognize the intracranial structure on CT scans. In the second stage, the intracranial structures on CT scans become clearer. Around the lateral ventricle a symmetrical high-density area appears, which corresponds to the germinal matrix. However, at the third stage, the high-density area disappears. The morphological changes of the ventricular system with growth are ascribed to a remarkable development of the cerebral parenchyma.
Trapping and EC-IC bypass surgery was performed for two cases of internal carotid aneurysm using the radial artery as bypass material. Neither case has any permanent neurological deficit because of an adequate blood supply via the radial artery graft bypass. Although the radial artery graft has been in common use among cardiac surgeons, it is still rare in the neurosurgical field. The advantage of the radial artery is discussed with comparison to other graft materials such as saphenous vein and superficial temporal artery. In properly selected cases, the radial artery graft is efficient in preventing the ischemic damage caused by trapping of aneurysm at the main arterial trunk.
Eighteen patients with vertigo, tinnitus, and various hearing disturbances were treated by posterior fossa exploration and microvascular decompression of the eighth cranial nerve; they were followed for more than 3 years. After successful decompression of the eighth nerve from offending vessels, the attacks of vertigo disappeared in 11 patients, improved markedly in 3 patients, and improved mildly in 4 patients. The tinnitus vanished in three patients and decreased in nine. The hearing disturbance improved in only five patients and worsened in three. Because of the satisfactory improvement of the attacks of vertigo, which are the most distressing symptoms for patients, we recommend surgical exploration for patients with severe symptoms of vestibular disturbances.
A technique for reconstruction of a cerebral cortical vein which has been sacrificed during an interhemispheric or subtemporal surgical approach is described. The method involves the use of silicone tubing. The author's clinical experience in six patients is summarized.
Angiography is essential to diagnosis and treatment for the patients with ruptured intracranial aneurysm in early stage, but on the other hand angiography always involves a risk that extravasation (EV) occurs from the aneurysm during angiography. Once EV occurs, the patient's outcome is poor and, in general, the patient tends to be regard as hopeless of recovery. Over the past 5 years, in 154 patients with ruptured intracranial aneurysm angiography was performed, and in 7 of them EV occurred. We performed neck clipping for ruptured aneurysm in 3 of 7 patients and were able to save the life of 2 patients. We investigated factors to cause EV and to decide outcome in 7 cases and 75 cases of literature, totally 82 cases. Following results were obtained. Occurrence of EV seems to be related to the causal factors of the time interval (within 6 hours) from SAH to angiography and the severity of disturbance of consciousness prior to angiography. It is considered that the patient's outcome is related to age, pre-angiographic severity of disturbance of consciousness, and also time interval from SAH to angiography, but the extent of EV and the number of past history of SAH are not important as the factors related to the outcome. Consequently, the utmost care must be taken for cerebral angiography particularly in patients within 6 hours after the onset of SAH, and in patients with severe disturbance of consciousness. Even if EV should occur, there is a fair chance for life-saving by an emergency surgery in cases with mild disturbance of cerebral function before angiography.