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Biomedical subjects

K Hashi

Publications and source records attributed to K Hashi.

At least 37 records · Page 2Linked to original sources
PubMed1998

Intellectual functions and regional cerebral haemodynamics after extensive omental transplantation spread over both frontal lobes in childhood moyamoya disease.

Most accepted operations for childhood moyamoya disease have attempted to increase cerebral blood flow (CBF) in the ischaemic cortical areas around the central fissure. Developed ischaemic brain damage in the prefrontal area may lead to poor intellectual outcome and restrict patients' daily lives. Thus, extensive cerebral revascularization in both the ischaemic anterior and middle cerebral artery territories is mandatory. We describe the long-term follow-up results for intellectual outcome and performance status and make an evaluation of regional cerebral haemodynamics after extensive omental transplantation spread over both frontal lobes performed as the initial management. In the past 10 years, 10 moyamoya patients less than 12 years of age consecutively underwent omental transplantation. The omental flap was spread over not only the symptomatic hemisphere but also the contralateral frontal lobe after a large craniotomy. Superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis was accomplished simultaneously. On the contralateral hemisphere, STA-MCA anastomosis combined with encephalomyosynangiosis was subsequently performed. The clinical observation period averaged 6.7 years (ranged 1.9 to 9.2 years). Apart from 2 patients in whom severe mental retardation had been disclosed pre-operatively, full-scale intelligence quotient scores have been maintained at over 90, that is, within the normal intellectual range. With respect to quality of life (QOL), these 8 patients have been leading normal daily lives since the operation. The focal decrease in CBF observed in the frontal lobe pre-operatively in 7 cases had disappeared after surgical treatment. In these patients, serial post-operative MR angiography revealed developed omental vessels and STAs. Deterioration of intellectual functions and QOL as well as cerebral ischaemic events in paediatric moyamoya patients can be prevented by extensive omental transplantation spread over both frontal lobes combined with STA-MCA anastomosis.

Cerebral Revascularization↗
PubMed1998

Intracranial facial nerve neurinoma: surgical strategy of tumor removal and functional reconstruction.

BACKGROUND: Three cases with intracranial facial neurinoma underwent tumor removal and facial nerve reconstruction with or without tympanoplasty. Surgical strategy for each case was tailored to: (1) the site of main tumor mass, (2) its extension along the facial nerve, and (3) involvement of the auditory organs. METHODS: Surgeries adopted in the three cases were: transpetrosal approach with intracranial-intratemporal facial nerve anastomosis, middle fossa and transmastoid approach with intratemporal facial nerve anstomosis and tympanoplasty, and middle fossa and transmastoid approach with intracranial-intratemporal facial nerve anastomosis and tympanoplasty. The greater auricular nerve was used as the nerve graft for all three cases. RESULTS: In the follow-up period of 8-13 months there was no tumor recurrence; facial function was scored 20/90 in modified May's scoring system in each case, but two are still in the process of functional recovery. One of the two cases who underwent tympanoplasty showed complete recovery of hearing within 1 month, and the other showed worsened hearing, which was not serviceable at 3 months postoperatively. CONCLUSION: Systematic surgical approach for tumor removal, facial nerve reconstruction, and auditory reconstruction should be considered in cases with intracranial facial neurinoma due to its varied clinical features.

Aged↗
PubMed1998

[Direct continuous observation of in situ thrombolysis in the cerebral embolic model of rabbits].

To investigate the occurrence of cerebral embolism, a rabbit embolic stroke model was used for the continuous monitoring of the change of the thrombus. Red thrombus was directly injected into the internal carotid artery via the catheter inserted into the external carotid artery. The migration of the thrombus into the middle cerebral artery was judged as the completion of an embolism. The change of the thrombus and its movement was observed for a period of two hours. The experimental group received recombinant tissue plasminogen activator (TPA) for the thrombolysis while the control group received a saline solution for 30 minutes. The thrombus in the middle cerebral artery was continuously observed for two and a half hours. 1. There was a spontaneous movement of the thrombus during the first two hours in six out of 18 cases. One case showed a spontaneous regression in size at the migration site. 2. White thrombus formation occurred around the thrombus in eight out of 18 cases. 3. In the TPA injected group, thrombolysis was observed in nine out of ten rabbits. The accompanied white thrombus was also found to be degraded. However, after the TPA injection, white thrombus was newly formed during the lysis of red thrombus. 4. In the saline solution injected control group, only partial recanalization occurred in three out of eight rabbits. There was no white thrombus formation in the control group. 5. There was no significant difference in the degree of Evans blue exudation between these two groups. Secondary activation of the platelet function easily occurred by the change of the blood flow during thrombus migration and also thrombolysis. In conclusion, thrombolysis therapy may be more effective when TPA is administered in conjunction with the suppression of platelet function.

Animals↗
PubMed1998

[Visual acuity outcome and recurrence in large or huge pituitary adenomas operated with transcranial approach: comparison between frontotemporal and interhemispheric approaches].

Pituitary macroadenomas which required transcranial removal were reviewed concerning visual acuity outcome as well as recurrence. We encountered 173 pituitary adenomas of which 27 (15.6%) were removed transcranially during the past 13 years. Eight cases were excluded due to inadequate information and improper utilization. Thus, a total of nineteen cases were reviewed in which the frontotemporal (FT) approach was utilized for seven cases and the interhemispheric (IH) approach for 12 cases. The mean size and volume of the tumors in the FT group were 3.0 x 3.7 x 3.1 cm and 18.2 cm3. The main reason for utilizing this approach was the fact that the tumors extended laterally involving the unilateral cavernous sinus or that unilateral preoperative visual acuity was obstructed. The visual acuity outcome was as follows: In six cases showing useful visual acuity on both sides before surgery, no apparent aggravation on either side was found in four cases, while in two cases there was complete obstruction on the operative side. The remaining case showed aggravation on both sides, though the approach side was decided upon because of the obstructed vision on that side. The mean size and volume of the tumors in the IH group were 4.6 x 4.8 x 4.9 cm and 71.1 cm3. This approach was used due to the extreme suprasellar extension because of the large size of the tumors. Although the tumors were relatively large and the visual acuity was assessed as fair prior to surgery, visual acuity showed no significant deterioration after the operation and was found to be satisfactory in 11 out of 12 cases. The complications in the FT group were oculomotor palsy in 3 cases, hemorrhage in one case, and frontal infarction in one case. On the other hand, three cases suffered hemorrhage in the tumor cavity of the IH group, though none needed surgical evacuation. Most of the cases in the IH group showed pituitary hypofunction following the surgical removal of the tumors as compared to the cases in the FT group. Recurrence had occurred, in some cases, several years after the operation. Furthermore, some of the tumors are still growing larger following only partial or subtotal removal. The prime aim of the treatment for huge pituitary adenomas which require the transcranial removal is to retain as much visual acuity as possible. In conclusion, the IH approach has been shown to be preferable in this situation. The FT approach was found to be more dangerous in terms of visual outcome than had been expected, even if the tumors were not particularly large.

Adenoma↗
PubMed1998

Chemical, metabolic and immunological characterization of gangliosides of human glioma cells.

The patterns of ganglioside profiles were studied in 10 human glioma and one melanoma cell lines. Ganglio-series gangliosides, GM3 (NeuAc alpha2-3Gal beta1-4Glc beta1-Cer) and GM2 (GalNAc beta 1-4 (NeuAc alpha2-3)Gal beta1-4Glc beta 1-1Cer), and a neolacto-series ganglioside, sialylparagloboside (SPG) (NeuAc alpha 2-3Gal beta1-4GlcNAc beta1-3Gal beta1-4Glc beta1-1Cer), were the predominant constituents. The activities of the two key enzymes, GM3 synthetase and lactotriaosyl ceramide (Lc3Cer) synthetase, alone did not account for the ganglioside profile. Metabolic labeling with the use of [3H]glucosamine-HCl showed more pronounced difference in the synthetic rate of each ganglioside type, in which GM2 was the most strongly labeled in 7 out of the 10 glioma cell lines. On quantifying the chemical content of GM3 and GM2, the GM3/GM2 molar ratio of above 2.0 was arbitrarily classified into GM3 dominant type (KG-1C and Mewo); the ratio below 0.5 was designated as GM2 dominant type (H4, U138MG, U373MG, T98G and A172); and the ratio between 0.5 and 2.0 was regarded as GM3 and GM2-co-dominant type (U87MG, Hs683, SW1088 and U118MG). Subsequently, the capabilities of the antibody binding to these gangliosides were examined in native forms in the cell membrane and in chemically-isolated forms. The intensity of reaction against chemically isolated GM3 and GM2 gangliosides was dependent on the quantity, and GM2 was more reactive than GM3; however, the reactivities on the cell surface did not correlate with the chemical content indicating other factors to influence their immunoreactivities.

Antibodies, Monoclonal↗
PubMed1997

Cell density regulates crypticity of GM3 ganglioside on human glioma cells.

Human glioma cell line KG-1C contains GM3 ganglioside as its sole glycolipid. The degree of M2590 antibody binding to GM3 was found to be regulated by the cell density; the percentage of positive cells in FACS analysis decreased from approximately 20% to close to none as the cells increased their density from sparse to confluent. The contents of GM3 with different cell densities were consistent, being more than 0.4 micromol/g of the cellular weight, which was high enough to be recognized by the antibody. Trypsin treatment of the cells did not increase antibody reactivity. The extracted GM3 retained its antigenicity, being intensely stained with M2590 on a TLC plate; there was no change in chromatographic mobility either, indicating no modification of its chemical structure. The fluorescent microscope disclosed scattered dot-like staining of GM3, particularly at the periphery of the cells. We were able to expose cryptic GM3 fully within 12 h by dispersion of the cells to a sparse density. Surface labeling of GM3 with the use of limited sodium periodate oxidation of sialylated residue equally labeled GM3 either from the confluent cells or the sparse cells. Disassembly of actin filaments with cytochalasin B (10 microM) partially exposed cryptic GM3 of confluent cells, indicating reversibility of the crypticity. All together, the results indicate that cryptic GM3 actually exists on the cell surface, hidden from the surface not by other molecules but by other mechanisms associated with the cellular architecture. We are beginning to explore the possibility of selective localization of GM3 in small caves or folds of the cell membrane produced upon cell-to-cell contact.

Antigens, Neoplasm↗
PubMed1997

Deletion of complex gangliosides of human glioma cells during mitotic cell division.

Glycolipid compositions of the human glioma cell line T98G were studied during each phase of the cell cycle to see if those cell surface molecules are concerned with cell proliferation. In vitro cultured non-synchronized T98G cells are composed of ceramidemonohexoside (CMH), ceramidedihexoside (CDH), ceramidetrihexoside (CTH) and neolactotetraosylceramide (nLc4Cer) as neutral glycolipids, and of sulfatide (CS), gangliosides GM3, GM2, GD1a and several other gangliosides as acidic ones. While total glycolipid content per cellular weight was shown to be increased during the M phase, deletion of complex gangliosides particularly b-series gangliosides was recognized (p < 0.05). The glycolipid profile in other phases was fairly consistent, and there was no glycolipid molecule specific to a certain phase of the cell cycle. Relative enhancement of simple gangliosides with a decrease of complex ones during mitotic division may imply the functional involvement of complex gangliosides in cell-cell or cell-matrix attachment, which may have to be abandoned during the process of detachment from the matrix or cellular cleavage.

Cell Division↗
PubMed1997

Supratentorial glioma manifesting as acute onset of pure motor hemiparesis--case report.

A 68-year-old male presented with an anaplastic astrocytoma deep in the sensorimotor cortex manifesting as acute pure motor hemiparesis suggestive of a vascular mechanism rather than tumor mass effect. Perfusion-weighted magnetic resonance (MR) imaging showed a significant decrease of blood flow in the sensorimotor area, where fluid-attenuated inversion recovery imaging demonstrated a prominently edematous area. Angiography also suggested ischemia with poor visualization of the precentral and central arteries. Diffusion-weighted MR imaging failed to identify the edema as cytotoxic or vasogenic due to technical problems. Brain tumors may manifest through impairment of peritumoral blood supply, which can be clarified by recent MR methods.

Aged↗
PubMed1997

Lymphoplasmacyte-rich meningioma with clinical resemblance to inflammatory pseudotumor. Report of two cases.

Two cases of lymphoplasmacyte-rich meningioma manifesting clinical and radiological characteristics unusual for a meningioma are reported. The patient in Case 1 was a 22-year-old man with a 9-year history of bilateral visual disturbances and recent dyspnea. An en plaque skull base mass, which was partially resected, was found at surgery to extend down from the planum sphenoidale into the spinal canal to C-5. Seven years later most of the residual mass in the spinal canal had disappeared, although a localized round tumor recurred at C2-3. The patient in Case 2 was a 24-year-old woman with an original diagnosis of clival meningioma, which recurred as multiple skull base lesions that spontaneously regressed in 10 months. These two cases and others reported in the literature indicate that lymphoplasmacyte-rich meningiomas may manifest peculiar biological behavior more typical of intracranial granulomas than of meningiomas.

Adult↗
PubMed1997

[Factors influencing the long-term function of the facial nerve following removal of acoustic neurinomas].

Thirty-five cases with removal of acoustic neurinomas were reviewed to demonstrate the factors which influenced the postoperative long term function of the facial nerve. All cases were operated on via a suboccipital route. The group consisted of 7 cases with the tumor confined to the internal auditory meatus, 4 cases with a neurinoma of 20 mm or less in diameter, 13 cases with a neurinoma of 30 mm or less, and 11 cases with a neurinoma over 30 mm. The consistency of the tumors was solid in 27 cases, and cystic in 8 cases. Dislocation of the facial nerve was observed during the operation except in 7 intrameatal cases. The dislocation is summarized as follows: dislocated in the cranial direction in 2 cases, ventrocranial in 7, ventral in 5, ventrocaudal in 10, dorsocaudal in one, and caudal in 3 cases. No case showed dislocation of the facial nerve in the dorsocranial or dorsal direction. Careful observation of the facial nerve at the entrance of the internal auditory meatus showed a severe kinking in 2 cases, moderate kinking in 2, but no kinking at all in the remaining 31 cases. The facial nerve was preserved anatomically in all cases. Long term function of the facial nerve can be summarized as excellent in 18 cases, good in 8 cases, and poor in 9 cases. Three cases showed an almost complete paresis of the facial nerve immediately after the operation and recovery was never observed. Neurinoma facial score was defined in 28 cases, except intrameatal cases, according to the degree of preoperative facial nerve function, tumor size, presence of the cystic component within the tumor, direction of the facial nerve dislocation, and the presence of kinking of the facial nerve. The correlation between the long-term facial nerve function and the neurinoma facial score was statistically examined and was found to be significant (Sperman's correlation coefficient by ranks; rs = 0.38596 > 0.375; P = 0.05). In conclusion, neurinoma cases that show the least facial nerve function are: cases in which facial function had deteriorated, cases in which the tumor was large or when the tumor had no cyst, when dislocation of the facial nerve was in the cranial direction, and in cases where there was kinking of the facial nerve at the internal auditory meatus. In such cases, the removal should be carried out intracapsularly so as to preserve facial nerve bundle which may spread and become flattened like a tumor capsule. This might minimize the postoperative deterioration of the facial nerve function.

Adult↗
PubMed1997

[Hippocampal hemosiderin deposit due to large pituitary adenoma presenting temporal lobe epilepsy--a case report].

There have been reports of epilepsy associated with pituitary adenoma, but the epileptogenic zone and its histopathology have never been sufficiently described. We report a case of pituitary adenoma complicated by temporal lobe epilepsy, in which the epileptogenic focus was identified, resected, and examined histopathologically. The patient was a 38-year-old man on bromocriptine therapy for a huge pituitary adenoma (prolactin-producing) since 1985. He also had a history of temporal lobe epilepsy since 1989. CT images in 1985 revealed the tumor extending to the supra- and left para-sellar region. MR images in 1995 showed a significant decrease in the size of the tumor and a signal void area that was interpreted as a hemosiderin deposit in the left mesial temporal lobe. Ictal EEG demonstrated that seizure discharges were elicited at the left sphenoidal electrode and propagated to the both temporal lobes. Interictal SPECT revealed a local area of hypoperfusion in the left fronto-parietal lobe. An epileptogenic focus in the left mesial temporal lobe was diagnosed on the basis of the above examinations. The patient was treated by left anterior temporal lobectomy with partial hippocampectomy. Hemosiderin deposition in the hippocampus was suspected during surgery. Histopathological examination showed pyramidal cell loss and gliosis in the left hippocampus and confirmed the presence of hemosiderin in the CA1 region. The hemosiderin deposition in the hippocampus was inferred to have resulted from intratumoral hemorrhage due to bromocriptine therapy, and it may have caused the temporal lobe epilepsy in this patient. The outcome of surgery was freedom from seizures for eight months. Intra-tumoral hemorrhage in mesial temporal structures must be borne in mind as one of the epileptogenic mechanisms in pituitary adenoma, especially in cases in which hemosiderin is detected on MR images.

Adenoma↗
PubMed1997

[Two cases of delayed posttraumatic vasospasm followed by brain SPECT].

This is a report of two cases of delayed posttraumatic vasospasm. In case 1, a 68-year-old male was injured by falling. He did not show any neurological deficits on admission. CT scan revealed a diffuse subarachnoid hemorrhage (SAH) without brain contusion. Aneurysm was not disclosed by angiography. On the 7th day after admission, he presented disorientation. Reviewed angiography revealed diffuse delayed vasospasm. 123I-IMP brain SPECT showed an extensive low perfusion area in the bilateral parietal portion. In case 2, a 71-year-old female experienced immediate development of a deep comatose state after head injury. CT scan on admission disclosed a massive acute left subdural hematoma and the severe compression of the left cerebral hemisphere by the hematoma. But traumatic SAH was not diffuse and was restricted to the left basal cistern. After emergency operation, her consciousness level improved and the mass effect of the subdural hematoma was diminished. On the 7th day after the operation, her neurological condition worsened. CT scan showed some infarction lesions in the left cerebral hemisphere and mild left cerebral swelling. Angiography on the same day revealed vasospasm in M2-M3 portion of left middle cerebral artery. HM-PAO brain SPECT disclosed low perfusion in the left parietal region, but a state of high perfusion in the other region. In case 1, vasospasm might have been derived from diffuse clots of traumatic SAH caused by the same process as postruptured aneurysmal vasospasm. In case 2, the region of vasospasm was not associated with traumatic SAH. It corresponded to the site of the brain contusion. It was suggested that the cause of vasospasm might have been the direct mechanical injury to the arterial wall and chemical substances deriving from the contused brain tissues. We conclude that SPECT or transcranial Doppler monitoring should be used for the early detection of posttraumatic vasospasm.

Aged↗
PubMed1997

[Direct surgical management of giant and large intracerebral aneurysms, associated with intraluminal thrombus and/or atherosclerotic thickening of aneurysmal neck].

Direct surgical management of giant or large cerebral aneurysms remains one of the most challenging topics in the neurosurgical field. Surgical results have remained unsatisfactory. We review 22 cases of large or giant aneurysms with intraluminal thrombus and/or atherosclerotic thickening of the aneurysmal neck that have received direct surgical management in our department during the period from 1984 to 1996. As initial symptoms, ten patients presented with mass effect, five with ischemic attack, and three with subarachnoid hemorrhage. Sixteen aneurysms were supratentorial and six were in the posterior fossa. Direct neck clipping was attempted in sixteen cases. Two giant basilar aneurysms among them were clipped under deep hypothermia with cardiac arrest. Simple trapping of the parent artery was performed in three aneurysms and trapping with bypass graft was also carried out in three aneurysms. Ten patients made an excellent clinical recovery. Eleven patients suffered mild to severe disability. One death resulted from brain stem infarction, not directly related with surgical management. Appropriate preoperative assessment and intraoperative management of the associated thrombus and atherosclerotic change of the aneurysmal neck are essential for obtaining acceptable surgical results of large or giant cerebral aneurysms.

Adult↗
PubMed1996

Radiation induced intracranial leiomyosarcoma: its histopathological features.

This is a case of intracranial sarcoma which was recognized 23 years after irradiation therapy for pituitary adenoma. Four operations were performed because of recurrences with a short interval between each operation. Immunohistochemically, the tumour cells were stained for smooth muscle actin, human muscle actin and vimentin. It was verified as a leiomyosarcoma. This report is the first case of intracranial leiomyosarcoma associated with radiation therapy in pituitary adenoma.

Adenoma↗
PubMed1996

A case of calcification of the cervical ligamentum flavum.

We report a case of cervical myelopathy caused by the calcification of the cervical ligamentum flavum. A 42-year-old woman with gait disturbance and an episode of dysuria was transferred to our hospital on June 30, 1994. Neurological examination revealed only a mild right hemiparesis. A plain neck X-ray and a tomogram revealed a nodular calcification in the posterior part of the spinal canal at the level of C5/6. Three dimensional computed tomography clearly demonstrated that the mass consisted of three nodular structures on the vertebral lamina. Magnetic resonance images demonstrated severe compression of the spinal cord by the mass whose intensity was low. The mass was removed en bloc together with the ligamentum flavum and C5 and C6 lamina. The mass showed no continuity to the dura mater. The calcification was confined within the ligament. The patient's neurological deficits were resolved two weeks after the surgery. X-ray diffraction study demonstrated the component of the mass was found to be pure hydroxyapatite. Clinical features of calcification of the ligamentum flavum are reviewed from 85 reported cases including ours, and the difference between this calcification and the ossification of the ligament is emphasized. Calcification of the ligamentum flaum is a distinct clinical entity.

Adult↗
PubMed1996

[Surgical approach for cervical dumbbell type neurinoma: posterior approach by partial hemilaminectomy with preservation of a facet joint].

We report on a case harboring a cervical dumbbell type neurinoma. The tumor was completely removed by a modified posterior approach, consisting of partial hemilaminectomies of C2 and C3 with preservation of the facet joint. The operative field under microscope was limited by the preserved facet joint of C2/3. However, sufficient bulk reduction of the epidural and paravertebral mass enabled us to obtain a good operative field. The paravertebral mass, which extended anteriorly to just beside the posterior aspect of the carotid sheath, was removed through the lateral space. The operative field was easily widened beside the right facet joint of C2/3 with partial removal of the posterior part of the transverse process of C2 and C3. The transit portion of the tumor to the normal nerve fiber was also identified through this space. The intracanalicular mass was removed by the partial hemilaminectomies of C2 and C3 without compressing the dural sac. Following sufficient reduction of the bulk, the right vertebral artery was identified at the anteromedial margin of the enlarged intervertebral foramen. Finally the intradural part of the tumor was removed through this space. Our modified posterior approach is a less invasive method to the bony elements of the cervical vertebrae and may minimize the incidence of postoperative instability and angular deformity. This approach also eliminates the necessity of long postoperative immobilization using a rigid cervicothoracic brace.

Cervical Vertebrae↗