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Biomedical subjects

K Kyoshima

Publications and source records attributed to K Kyoshima.

At least 55 records · Page 3Linked to original sources
PubMed1993

A study of safe entry zones via the floor of the fourth ventricle for brain-stem lesions. Report of three cases.

Direct surgery for intra-axial lesions of the brain stem is considered a hazardous procedure, and morbidity of varying degrees cannot be avoided even with partial removal or biopsy. The main causes of morbidity relate to direct damage during removal of the lesion, selection of an entry route into the brain stem, and the direction of brain stem retraction. The authors examined the possibility of making a medullary incision and retracting the brain stem, taking into account the symptomatology and surgical anatomy, and found two safe entry zones into the brain stem through a suboccipital approach via the floor of the fourth ventricle. These safe entry zones are areas where important neural structures are less prominent. One is the "suprafacial triangle," which is bordered medially by the medial longitudinal fascicle, caudally by the facial nerve (which runs in the brain-stem parenchyma), and laterally by the cerebellar peduncle. The second is the "infrafacial triangle," which is bordered medially by the medial longitudinal fascicle, caudally by the striae medullares, and laterally by the facial nerve. In order to minimize the retraction-related damage to important brain-stem structures, the brain stem should be retracted either laterally or rostrally in the suprafacial triangle approach and only laterally in the infrafacial triangle approach. Three localized intra-axial brain-stem lesions were treated surgically via the safe entry zones using the suprafacial approach in two and the infrafacial approach in one. The cases are described and the approaches delineated. Both approaches are indicated for focal intra-axial lesions located unilaterally and dorsal to the medial lemniscus in the lower midbrain to the pons. Magnetic resonance imaging is useful in selecting these approaches, and intraoperative ultrasonography is helpful to confirm the exact location of a lesion before a medullary incision is made. These approaches can also be used as routes for aspiration of brain-stem hemorrhage as well as for tumor biopsy.

Adult↗
PubMed1993

[Arteries to the pituitary].

The arteries of the pituitary stalk and gland were described using our results as well as data obtained from the literature. There were three types of vessels to the pituitary from above: the superior hypophyseal artery originating from the internal carotid artery, the infundibular artery originating from the posterior communicating artery, and the prechiasmal artery from the ophthalmic artery. There were also three arteries from the cavernous carotid artery; the inferior hypophyseal artery, the capsular artery, and the artery of the inferior cavernous sinus. These arteries were anastomosed each other, making the rich vascular networks, called the "circuminfundibular anastomosis" around the pituitary stalk, and the "inferior hypophyseal arterial circle (or inferior capsular arterial rete)" in the base of the pituitary.

Carotid Artery, Internal↗
PubMed1993

[Central nervous system metastasis from lingual carcinoma: report of a case].

A rare case of lingual carcinoma which metastasized to the brain is reported. A 66-year-old man was referred to our department on April 23, 1991, with complaints of memory disturbance and mild left motor weakness of one month's duration. The patient had been discharged from the Department of Otolaryngology of our hospital 9 months before, after undergoing radical neck dissection and chemotherapy (THP, CDDP, PEP) for his lingual cancer with metastases to the cervical lymph nodes and the lung. On admission to our department, the patient complained of mild frontalgia. Neurological examination showed memory disturbance, change of character, mild left hemiparesis and urinary incontinence. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a well circumscribed mass in the right frontal lobe associated with midline shift toward the left. Systemic Gallium-67 scintigraphy demonstrated an abnormal uptake in the right frontal region, but no abnormal uptake was seen in the neck and the lung. The most likely diagnosis was thought to be metastasis of lingual cancer. The patient underwent tumor removal 10 days after admission. A histological examination of the tumor specimen revealed metastatic anaplastic cell carcinoma, indicating a metastasis from lingual carcinoma. After postoperative radiotherapy (total 60 Gy), the patient was discharged without neurological deficit. Central nervous system metastasis from lingual carcinoma is quite rare. To the best of our knowledge, only two such cases have been reported. We report another rare case of solitary brain metastasis from lingual carcinoma and review the pertinent medical literature.

Aged↗
PubMed1992

[Growth of the graft and astrocytic reaction following transplantation of fetal brain to adult rat's brain. Part I: Tissue transplantation into cerebral cortex, lateral ventricle, subarachnoid space and cerebral cortical cavity].

Brain transplantation has been examined as one of the therapeutic methods in the animal models of Alzheimer's disease. Among a lot of problems inherent to therapeutic brain transplantation, we have investigated implanting techniques and methods. Small pieces of fetal basal forebrain tissue containing cholinergic neurons were transplanted into adult rats' cerebral cortex, lateral ventricle, subarachnoid space, and the cerebral cortical cavity which had been made 10 days before transplantation (delayed cavity technique). Two to 3 months after transplantation, growth of the grafts, neurites elongation and astrocytic reaction were observed by Nissl staining, histochemical staining for acetylcholinesterase and immunocytochemical staining for glial fibrillary acidic protein (GFAP). Intracortical grafts were small and surrounded by thick glial scar formation, but there was found a partial lack of glial scar and host-graft neuronal integration was also observed. Both intraventricular and subarachnoid grafts grew relatively well. GFAP-immunoreactive cells had a tendency to gather near the margin of the graft and perivascularly. These facts seemed to suggest that reactive astrocytes were also taking part in support of the homeostasis of environments in the graft tissue. By delayed cavity technique, better growth of the grafts was observed, but dense glial and connective tissue scar tissues developed and prevented the outgrowth of neuronal processes. Nevertheless, hyperinnervation from graft to host cortex was partially noticed. It should be stressed that although the hyperinnervation may be effective for recovery of the host from the central nervous system damages, it may possibly damage the host's neuronal circuits.

Animals↗
PubMed1992

[Growth of the graft and astrocytic reaction following transplantation of fetal brain to adult rat's brain. Part II: Cell suspension transplantation into the subarachnoid space].

Suspensions of basal forebrain cells of fetal rats were transplanted into the subarachnoid space of adult rats through a microsyringe needle which was transcortically inserted to the subarachnoid space. Two to 3 months after the transplantation, growth of the graft, neuritic elongation, neovascularization, and astrocytic reaction were examined by Nissl staining, histochemical staining for acethylcholinesterase and Klüver-Barrera's myelin staining, vascular relief images and immunohistochemical staining for laminin, and immunocytochemical staining for glial fibrillary acidic protein (GFAP). Transplanted fetal neurons survived and grew very well over the brain surface and exhibited facilitated neuritic elongation. Several bundles of myelinated fibers linking the subarachnoid and the subpial grafted cells were noticed, but the myelinated fibers penetrating the intact pia mater were not verified. In the grafted tissue, extracellular matrix was formed and a lot of small vessels and capillaries were noticed. Many GFAP-immunoreactive cells were seen in the graft. They had a tendency to gather perivascularly and near the margin of the graft tissue facing subarachnoid space. The subarachnoid space is thought to be an adequate place for transplanted neuronal and glial cells to grow. The subarachnoid space contains the cerebrospinal fluid and also it contacts with rich pial vessels, so that it seems to be superior to the intraparenchymal area in respects of a supply of oxygen and nutrition and of low tissue pressure. Transplanted tissue may be supposed to work as the exocrine and/or endocrine organ which secretes neurotransmitters and their synthetic enzymes and neurotrophic factors. If this is true, it would imply that the subarachnoid space is considered as a promising site for implantation.

Animals↗
PubMed1992

Dorsal internal carotid artery aneurysms with special reference to angiographic presentation and surgical management.

Aneurysms arising from the dorsal wall of the internal carotid artery are rare. The authors surgically treated twenty dorsal internal carotid artery aneurysms. Pre-operative angiographic findings were reviewed and classified into three types. Eleven aneurysms projecting superiorly on the lateral angiogram were found to be adherent to the base of the frontal lobe by the pterional approach. Five aneurysms which had been superimposed with the internal carotid artery on the lateral angiogram were found adhered to the medial surface of the temporal lobe. Four aneurysms not seen on the angiogram had no adhesion. Two aneurysms, which had not been seen on the initial angiograms, were visualized on the angiograms taken during the period of vasospasm. This type of aneurysms can be the source of a subarachnoid haemorrhage of unknown origin and requires repeated examinations. Premature rupture occurred intra-operatively in five cases and postoperative bleeding was encountered in two. Clipping technique is discussed from the viewpoint of preventing intra- and postoperative rupture.

Adult↗
PubMed1992

Multiple spinal neurinomas presenting visual disturbance as the initial symptom: case report.

A case of multiple spinal neurinomas with visual disturbance is reported. A 63-year-old man was admitted with a complaint of progressive visual disturbance due to papilledema without spinal symptoms and signs. The neuroimaging studies demonstrated communicating hydrocephalus and two mass lesions in the cauda equina. Both tumors were found to be neurinomas. Intracranial hypertension secondary to spinal tumors is unusual, and multiple spinal neurinomas are rare. In the patient without spinal symptoms and signs, it is difficult to make a diagnosis of spinal tumor. Importance of checking for a spinal cord lesion by magnetic resonance imaging in such a case is stressed.

Diagnosis, Differential↗
PubMed1992

Introduction of high definition television system to neurosurgical documentation.

The high definition television (HDTV) system is introduced to microneurosurgery. Five cases with intracranial lesions: three cerebral aneurysms (giant aneurysms of the anterior communicating artery and internal carotid artery, aneurysm of the basilar artery), one acoustic neurinoma and one skull base meningioma, were operated on under the microscope using the HDTV system. The surgical procedures of each case were relayed and recorded by the system. In two of the five cases, we used two sets of HDTV system to produce stereoscopic projection. The HDTV system provided us with images of superior quality with a distinctly greater resolution than ordinary video systems.

Adult↗
PubMed1992

Transpetrosal extreme lateral suboccipital approach for extensive posterior fossa epidermoid cyst--case report.

A new transpetrosal extreme lateral suboccipital approach was adopted to totally remove an extensive posterior fossa epidermoid cyst in a 36-year-old male. The pathological behavior of intracranial epidermoid cysts may impose surgical problems during removal of the tumor. However, planning based on neuroimaging allows optimum access to tumors and microsurgery achieves safer and more complete removal.

Adult↗
PubMed1992

Subfrontal schwannoma--case report.

A rare case of subfrontal schwannoma occurred in a 33-year-old male with the chief complaint of headache. Computed tomography demonstrated a low-density mass in the subfrontal region. Magnetic resonance imaging indicated the mass extension into the ethmoidal sinus. The tumor was totally removed via a subfrontal approach. The histological diagnosis was schwannoma. The most likely origin of the tumor is the meningeal branches or anterior ethmoidal nerve.

Adult↗
PubMed1992

A newly designed puncture needle for suction decompression of giant aneurysms. Technical note.

A newly designed puncture needle for aspirating large or giant aneurysms is described. This puncture needle represents a modification of an intravenous catheter with an internal needle. It is designed to prevent blood from leaking when the internal needle is removed and has a lateral tube for aspiration. Following aneurysm puncture with the parent artery temporarily trapped, the catheter is positioned on the head frame with a brain spatula and a self-retaining retractor. Blood is suctioned through the lateral tube with a syringe or the suction system normally used in the operating room.

Equipment Design↗
PubMed1992

[Reconstruction of anterior cranial base and face with free musculocutaneous flap; report of two cases].

The treatment of extensive cranial base tumor is still challenging. Wide resection of a cranial base tumor would lead to exposure of the vital structures such as the brain and dura, and would result in a large dead space in the cranium and in the connecting area between the nasal cavity and the intracranial space. Recently free tissue transfer has become a reliable method in the field of reconstructive surgery. In the craniofacial region, free tissue transfer is useful to reconstruct a complicated defect. We report two cases where free latissimus dorsi M-C flap and rectus abdominis M-C flap were useful in reconstructing the defect following removal of an anterior cranial base tumor. We discuss the advantages.

Aged↗
PubMed1991

Development of the operating computerized tomographic scanner system for neurosurgery.

A computerized tomographic (CT) scanner system for intraoperative imaging is presented. The system consists of the following: 1) CT scanner with a mobile gantry, 2) digitally controlled operating table with central processing unit (CPU) and encoder unit; the table can be controlled by the scanner computer as accurately as the scanner bed, and 3) exclusively designed head fixation devices. It allows us to scan the patient on the operating table in the operating room pre-operatively, intra-operatively and immediately after surgery.

Computer Systems↗
PubMed1991

Intraoperative monitoring of somatosensory evoked potentials in patients with cerebral aneurysm--correlation between central conduction time and postoperative neurological status.

Somatosensory evoked potentials (SEPs) were monitored during 55 aneurysm procedures in 49 patients to investigate the relationship between central conduction time (CCT) and neurological status in the immediate postoperative period. Significant CCT prolongation was observed in 15 cases. The postoperative neurological status deteriorated in nine of the 15 cases, compared with three of 40 cases without appreciable CCT changes. This difference was significant at p less than 0.05. The CCT prolongation was ascribable to temporary vascular occlusion in half of the cases. Intraoperative SEP monitoring is useful in predicting neurological morbidities in the immediate postoperative period in patients with cerebral aneurysm.

Adult↗
PubMed1991

[Generalized choreic movement associated with subarachnoid hemorrhage].

A case of generalized choreic movement associated with subarachnoid hemorrhage is reported. A 71 year-old hypertensive woman suddenly developed severe headache 14 days before admission. Consciousness disturbance and involuntary movement involving the face and upper extremities appeared about 8 days after onset. The involuntary motion was diagnosed as generalized choreic movement. CT scans showed subarachnoid hemorrhage with ventricular dilatation and periventricular lucency involving bilateral caudate nuclei. On admission the patient was stuporous with Hunt & Kosnik Grade 4. She showed involuntary choreic movement in both arms, trunk and face; hemiparenis and hyperreflexia were absent. An angiography revealed a right internal carotid-anterior choroidal artery aneurysm with vasospasm. After clipping the aneurysm in the following day, the consciousness disturbance and choreic movement gradually improved. By eight days after operation, the choreic movement completely disappeared. An MRI showed lacunar infarcts in the bilateral basal ganglia, predominantly in the caudate nuclei. In our case, the choreic movement is supposed to have been caused by impaired circulation in the bilateral corpora striata due to vasospasm and hydrocephalus after subarachnoid hemorrhage, in addition to the preexisting lacunar infarcts in the basal ganglia. This is claimed to be the first reported case of generalized choreic movement in associated with subarachnoid hemorrhage, which improved after surgery.

Aged↗
PubMed1991

[A case of disproportionately large communicating fourth ventricle (DLCFV) combined with syringomyelia and Chiari malformation].

We report a rare case of disproportionately large communicating fourth ventricle (DLCFV) combined with syringomyelia and Chiari malformation. The case was a 27-year-old male who underwent ventriculoperitoneal (V-P) shunt on the right side for hydrocephalus caused by traumatic intracerebral and intraventricular hemorrhage. One month later, he became somnolent with posterior fossa symptoms (nausea, vomiting and nystagmus). CT scan demonstrated enlarged fourth ventricle, which was diagnosed as DLCFV because the ventriculogram revealed patency of the aqueduct. One and half month later a second V-P shunt was made on the left side to increase the shunt flow. He became ambulatory with a cane, although the fourth ventricle remained moderately dilated on CT scan. Two months after the additional V-P shunt, he slipped and hit the occiput and immediately became tetraparetic. The patient was treated conservatively under the diagnosis of central spinal cord injury. The MRI taken 2 months after the accident revealed Chiari malformation (type 1), syringomyelia and a dilated fourth ventricle which was compressing the brainstem. After the fourth ventriculoperitoneal (FV-P) shunt, the tetraparesis transiently improved but then again worsened. On the CT scan the syrinx did non change in size, while the size of the fourth ventricle became normal. After syringoperitoneal (S-P) shunt the patient showed a moderate improvement of tetraparesis. Unfortunately he suffered appendicitis complicated with peritonitis and all the shunts were immediately changed to external drainage. However, the patient developed meningitis and became paraplegic. The motor function of the upper extremities slightly improved by aspiration of fluid via the external drainage system from the syrinx.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Astrocytoma with granular cell tumor-like changes. Report of a case with histochemical and ultrastructural characterization of granular cells.

A peculiar case of astrocytoma showing a histological appearance similar to granular cell tumor was reported. The tumor consisted of large round cells containing numerous intracytoplasmic eosinophilic granules, partially intermingled with atypical astrocytes, and part of it showed a transition to distinct areas of fibrillary astrocytoma. The granules were periodic acid-Schiff-positive (with resistance to diastase digestion), negative for fat stains and revealed lectin-binding patterns similar to those in granular cell tumor. Ultrastructurally the granules were partially membrane-bound, dense bodies compatible with secondary lysosomes. It was suggested that the granular cells were of astrocytic origin because of their immunoreactivity for glial fibrillary acidic protein (GFAP) and ultrastructural observation of intermediate filaments corresponding to GFAP.

Adult↗