Transient ischemic attack due to dissection of the middle cerebral artery--case report.

A 57-year-old man presented with a transient ischemic attack due to dissection of the middle cerebral artery. He suffered total aphasia and clouding of consciousness for several minutes. On admission, he was alert without neurological deficit. Magnetic resonance (MR) angiography and conventional angiography depicted irregularity and double lumen of the left middle cerebral artery. The diagnosis was dissection of the middle cerebral artery. After 1 month, he left our institute with no neurological deficit. Transient ischemic attack associated with dissection of an intracranial artery is unusual. The source images of MR angiography are useful for the essential follow up of dissection.

Improved method of determining retinol and retinyl palmitate in rat liver and serum by high-performance liquid chromatography.

In this study, we examined the effect of certain analytical procedures to determine the best method of recovering the ingested retinoids, specifically retinol and retinyl palmitate, from rat liver and serum. In this experiment, the best extraction solvent for retinol was n-hexane and that for retinyl palmitate was ethyl acetate. The best results were obtained using a mobile phase (n-hexane-diethyl ether, 76:24, v/v) as the sample solvent in the assay for liver retinol, similarly, chloroform as the sample solvent in the assay for serum retinol, and for liver retinyl palmitate, the best sample solvent was methanol-toluene (5: 5, v/v). The assayed values of retinol and retinyl palmitate measured in ethanol (0.125% BHT added) and extraction solvent (0.025% BHT added) were significantly higher than those when no BHT was added to the ethanol and extraction solvent. The determination methods for extracting retinol and retinyl palmitate from the liver varied according to the conditions layed out above. Simultaneous determination of retinol and retinyl palmitate has been illustrated in previous papers by various authors: however, we found that the individual determination of retinol and retinyl palmitate was necessary to accurately assay each retinoid.

Interventional neuroradiology in hemifacial spasm. Diagnostic and therapeutic implications.

SUMMARY: There have never been functional studies in the diagnosis of hemifacial spasm caused by neurovascular compression. We used neurointerventional techniques to conduct a functional investigation of the artery responsible for hemifacial spasm in seven patients. A microcatheter was inserted into the various arteries of the posterior circulation under systemic heparinization, and its effect on the spasm was evaluated clinically and electromyographically. In six patients who underwent microvascular decompression surgery, the vessels compressing the root exit zone of the facial nerve were surgically determined, and compared with the result of the procedure. The catheter was inserted into twelve arteries. The spasms were stopped immediately and completely by the insertion of the catheter into seven arteries. Six of them were surgically proven to compress the root exit zone of the facial nerve. The spasm was changed in frequency or in type by the insertion into two arteries. These arteries were also compressing the root exit zone. One artery was located at a more peripheral part of it and the other was running over another artery compressing the root exit zone. The spasms were not affected at all by the insertion into three arteries. These arteries were not observed in the operative field and had no contact with the nerve. Superselective angiograms showedpositional qnd configurational changes of the arteries. There was no arterial spasm and tight catheterization leading to stasis of contrast material within the arteries. There were no complications related to the procedures. Functional relationship between the artery and the spasms was established in all the patients, and one patient refused surgery because the frequency of the spasm was reduced by the procedure. The result of this study may suggest that a functional investigation of hemifacial spasm is feasible and seems useful for selecting good candidates for microvascular decompression surgery.

Endovascular stenting of the cervical internal carotid artery.

SUMMARY: The purpose of this study was to determine the value of stenting in the treatment of occlusive vascular disease involving the cervical internal carotid artery. Clinical and angiographical results of stenting were compared those of conventional angioplasty alone up to 20 months of follow-up. The Palmaz-Schatz stent was implanted in two patients with acute intimal dissection, whereas conventional angioplasty alone was performed in seven patients with arteriosclerotic stenosis. Initial procedural success was achieved in all the patients, and acute or subacute complications were not encountered at all. One of the patients (14%) treated with conventional angioplasty alone developed late restenosis at three-month follow-up. The patients treated with stenting revealed satisfactory results clinically and angiographically. The present results may suggest that stenting is an effective and safe method to treat dissection of cervical internal carotid artery, but larger clinical trials as well as experimental studies would be necessary to define the indications and refine the stents.

[Localization of the pyramidal tract in the internal capsule: relationship between CT classification of thalamic hemorrhage and motor weakness].

To better understand the pyramidal tract of the internal capsule, we evaluated the relationship between the localization of thalamic hemorrhage and motor weakness. On an axial CT scan at the level of the pineal body, two lines were drawn as follows: line-a between the lateral edge of the anterior horn and the lateral edge of the trigone, line-b vertical to the sagittal line and passing the midpoint of the third ventricle. The location of the hematoma was classified into three types according to localization of the center of the hematoma and lateral extension beyond line-a as follows: type A (anterior), type P (posterior) and type PL (postero-lateral). Discrepancy of motor weakness between upper extremities and lower extremities was higher in patients with hematoma of type P and type PL (p < 0.05) than in those with hematoma of type A. Improvement of motor weakness on discharge was higher in patients with type P (p < 0.01) than in those with type A. We concluded that most of the pyramidal tract fibers were located in the third quarter of the posterior limb of the internal capsule but a small number of pyramidal tract fibers were located in the anterior two-thirds of it. A greater number of cortico-spinal fibers to the upper extremities than to the lower extremities occupy the third quarter of the posterior limb of the internal capsule.

Repeating hemorrhage with a long duration after radiotherapy for glioma: radiological and histological observations.

A case of radiation necrosis which was observed 6 years after radiotherapy for a glioma in the right parietal lobe is reported. This patient developed hemiparesis, and radiological examinations showed similar findings consisted with recurrent glioma. Histological examination disclosed the lesion to be radiation necrosis. Repeated episodes of hemorrhage and cystic formation in the right hemisphere appeared during 8 to 10 years after radiotherapy, and removal of the mass lesion conducted four times. Histological examinations of each specimen showed the increasing proliferation of neo-vessels accompanied by hemorrhage and cystic formation.

Ruptured aneurysm of the distal posterior inferior cerebellar artery in a neonate--case report.

A 34-day-old male presented with a rare neonatal ruptured aneurysm of the distal posterior inferior cerebellar artery manifesting as a 10-day history of enlargement of head circumference. Magnetic resonance imaging revealed hydrocephalus and a round infratentorial enhanced lesion which compressed the medulla. Left vertebral angiography demonstrated an aneurysm on the telovelotonsillar segment of the left posterior inferior cerebellar artery. Ventriculoperitoneal shunt emplacement and proximal artery clipping were performed. The cerebrospinal fluid was bloody, suggesting aneurysm rupture had caused hydrocephalus. His postoperative course was uneventful, and neurological and developmental findings were normal 7 months later. Present neuroimaging, surgical, and neuro-anesthesiology techniques allow successful surgical intervention in cases of neonatal ruptured aneurysm.

[A case of successful acute revascularization using a long vein graft].

We experienced a case of successful acute revascularization using a long vein graft. A 68-year-old man was admitted to our department due to transient ischemic attack of the left hemiparesis. CT scan showed no infarction, but PAO-SPECT revealed moderate hypoperfusion in the right ACA and MCA area. Cerebral angiography demonstrated right IC occlusion at its origin and moderate collateral circulation via leptomeningeal anastomosis from the PCA area, and via the external carotid system, especially directly from STA. But the STA was very narrow. Three days after admission, left hemiparesis appeared again and deteriorated severely. This time the hemiparesis persisted. Although MRI demonstrated little infarction in the right frontal lobe, we decided to carry out revascularization on the same day. Right saphenous vein was harvested for a graft because of the narrow STA. The facial artery and angular artery was selected as a donor and a recipient respectively, to avoid a clamp of the EC and a craniotomy of the STA running area. Finally we performed a facial artery-vein graft-angular artery (M4) bypass. The patient showed no complication and the left hemiparesis improved enough to allow the patient to walk by himself. Revascularization using vein graft is dangerous for acute ischemia due to the possibility of a complication such as brain edema and hemorrhagic infarction. The usual style of vein graft bypass is an EC-vein graft-M2 or M3 bypass. Using this style, high pressure inside the EC is carried intracranially.(ABSTRACT TRUNCATED AT 250 WORDS)

Ruptured aneurysm associated with arachnoid cyst: intracystic hematoma without subarachnoid hemorrhage.

BACKGROUND: It is well-known that arachnoid cysts of the middle fossa are associated often with chronic subdural hematomas and/or intracystic hemorrhages. However, reports of an arachnoid cyst associated with an aneurysm are rare. CASE DESCRIPTION: A 45-year-old man was admitted with headache due to intracystic hemorrhage in the sylvian fissure, associated with a saccular aneurysm at the bifurcation of the internal carotid artery. The aneurysm ruptured into the arachnoid cyst, without causing a subarachnoid hemorrhage. Subsequently, the neck of the aneurysm was clipped successfully. The patient's postoperative course was uneventful, and there was no vasospasm. CONCLUSIONS: This is the first reported case of an intracystic hematoma due to a ruptured aneurysm. We discuss the possible etiology of the association between the aneurysm and the arachnoid cyst, and the formation mechanism for the intracystic hematoma that did not result in a subarachnoid hemorrhage.

The influence of total body hyperthermia on brain haemodynamics and blood-brain barrier in dogs.

This study was designed to examine the influence of total body hyperthermia (TBHT) using an extracorporeal circuit with a heat exchanger on the cerebral blood flow (CBF), intracranial pressure (ICP), brain tissue pH, cerebral autoregulation and blood-brain barrier (BBB) permeability in dogs. The rectal temperature of the dow was raised to 41.5 degrees C, maintained at 41.5-42.0 degrees C for 2 hours (HT period) and then reduced to normothermia by cooling. Regional CBF was measured by the hydrogen clearance method before heating, during the HT period and after cooling. ICP and brain tissue pH were monitored during the TBHT treatment. Autoregulation of the CBF during the HT period was assessed by measuring the regional CBF and the ICP in a state of induced hypo- or hypertension. The influence of TBHT on BBB permeability was examined using an immunohistochemical technique. The regional CBF increased from 38.1 +/- 6.5 (mean +/- SD) to 49.1 +/- 9.8 ml/100 g/min and the ICP from 10.3 +/- 4.2 to 16.8 +/- 3.4 mmHg when TBHT was raised. These returned to normal values after cooling. The regional CBF and the ICP changed in parallel with drug-induced changes of mean arterial blood pressure during the HT period. These changes suggest that autoregulation of the CBF is paralysed during the HT period. Brain tissue pH decreased rapidly when the rectal temperature exceeded 41.0 degrees C. The pH was 7.18 +/- 0.05 during the HT period and was relatively stable. The pH returned to a normal value after cooling. Immunopositive stain for albumin was not observed in heated brain tissue except for the normally leaky pineal gland and the choroid plexus, indicating preservation of BBB during TBHT. These results suggest that brain oedema may occur easily due to paralysed cerebral autoregulation when the arterial blood pressure fluctuates excessively, so arterial blood pressure must be controlled strictly during TBHT.

Effect of whole-body hyperthermia on the development of peritumoral brain oedema.

The effect of whole-body hyperthermia on the development of peritumoral brain oedema and intracranial pressure was studied in cats with intracerebral transplanted tumour. Whole-body hyperthermia was achieved by means of extracorporeal circulation. The temperature within the brain tumour tissue was increased to 41.8 +/- 0.15 degrees C (mean +/- SD) for 2 h. Measurements of brain water content revealed that hyperthermia worsened the degree of peritumoral brain oedema. Microscopical observation demonstrated that extravasation of horseradish peroxidase, indicating disruption of the blood-brain barrier in the oedematous region, was more severe in animals exposed to hyperthermia than in non-treated animals. Intracranial pressure significantly increased from 13.5 +/- 5.26 mmHg to 25.8 +/- 6.16 mmHg (p < 0.05) during hyperthermia, although it was controlled at 20.7 +/- 2.60 mmHg by continuous infusion of glycerol. The results suggest that whole-body hyperthermia acting on a brain-bearing tumour caused an increase in intracranial pressure due to worsening of the degree of peritumoral vasogenic type of brain oedema. We emphasize that whole-body hyperthermia may be performed with careful monitoring of intracranial pressure for patients who have brain tumour.

An artificial blood vessel with an endothelial-cell monolayer.

An artificial blood vessel with an endothelial-cell monolayer was used as an arterial substitute in rats. Endothelial cells were isolated from the aorta of a Wistar rat by the digestion method. The cell identification was established by the cobblestone appearance of a confluent cell monolayer, by an expression of factor VIII-related antigen, and by the presence of Weibel-Palade bodies. The luminal surface of the thin-walled polytetrafluoroethylene (PTFE) graft (4 mm in diameter and 10 mm in length) was coated with an endothelial-cell monolayer for 7 days in vitro. An interpositional graft was placed using the endothelial cell-coated PTFE prosthesis on the right common carotid artery in seven rats. A total of 10 rats received an interpositional graft with the noncoated PTFE prosthesis as a control. The patency rate at 1 month after implantation was significantly higher in the coated group than in the control group. The vascular prosthesis with an endothelial-cell monolayer is a promising technique to inhibit the development of thrombosis.

[Inventions for preservation of hormonal function in long-term culture of human functioning pituitary adenoma].

This study was designed to establish in vitro model systems in human hormone-producing pituitary adenomas that are analogous to the in vivo cellular environment. Mechanically dispersed cells composed of single cells and aggregates from 6 pituitary adenomas (3 GH producing adenomas and 3 prolactinomas) were cultured on microporous membrane cell culture inserts (Millicell-CM) coated with Basement Membrane Matrigel for up to 6 months. Growth hormone or prolactin in the medium was measured during the culture, and morphological feature in vitro was also compared with that of the original tumor at intervals. Not only single cells but also large aggregated cells which usually float in the medium when seeded on conventional plastic, were flattened and firmly attached to coated microporous membrane under the control of medium volume in culture. In both type adenomas, especially prolactinomas, surviving aggregated adenoma cells revealed preserved hormone activity and no dedifferentiation of cell characteristics after 6 months in culture. Particularly during the first 2 months in culture, close similarity existed between in vivo and in vitro conditions with regard to cell morphology and hormone release. These results indicate that this new culture method may further aid the investigation of in vitro cellular structure and function in human pituitary adenomas under conditions which closely mimic the in vivo cellular environment.

[Effect of calcium channel antagonist (nicardipine) on growth hormone and prolactin secretion in pituitary adenomas].

This study was designed to investigate the effect of calcium channel antagonist (nicardipine) on basal and bromocriptine-inhibited GH or PRL secretion in eight patients with pituitary adenomas (six GH producing adenomas and two prolactinomas). GH or PRL was measured in blood collected at intervals for 12 hours after oral administration of nicardipine (Nc) (40 mg) and/or bromocriptine (Br) (2.5 mg) in each case. In vitro, pituitary adenoma cells were incubated in media containing Nc (200 ng/ml) and/or Br (200 ng/ml) over a 72-h period, and then in drugs-free media for three days. Media were collected at 24-h intervals and assayed for GH or PRL. In three of six GH producing pituitary adenomas, GH secretion was inhibited by Nc both in vivo and in vitro. In prolactinomas, PRL secretion was inhibited by Nc in vitro, but in vivo, an increase of plasma PRL levels was observed after Nc administration in one of two cases. In two acromegalic patients and one patient with prolactinoma, Nc reduced the suppression of GH or PRL secretion induced by Br. These findings indicate that influx of extracellular calcium plays an important part in both GH and PRL secretion in functioning pituitary adenomas, and that Nc effects on GH and PRL secretion in pituitary adenomas by blocking of influx of calcium and/or antidopaminergic action. It is considered that the combined administration of calcium channel antagonist (Nc) and Br for acromegalic patients and administration of Nc for patients with prolactinomas should be avoided.

[Influence of total body hyperthermia on normal brain tissue].

The influence of total body hyperthermia (TBHT) on normal brain tissue was studied in 40 dogs. The dogs were anesthetized with sodium thiopental (10 mg/kg/hr) intravenously, and were ventilated by artificial respirator. The TBHT was induced by extracorporeal circuit in cooperating a heat exchanger. Rectal temperature was raised to 41.5 degrees C and maintained at 41. 5 -42.0 degrees C for 2 hr (HT period) and was then fallen to normothermia by cooling, Regional cerebral blood flow (CBF) was measured by hydrogen clearance method before heating, during and after TBHT treatment. Brain temperature, rectal temperature, intracranial pressure (ICP), brain tissue pH and electroencephalography (EEG) were monitored continuously during TBHT. Histopathological changes of the brain tissue were studied in dogs killed just after TBHT and 2 weeks after TBHT. Autoregulation of the CBF during HT period was assessed by measuring the regional CBF and the ICP at a state of induced hypo- or hypertension. The brain temperature (at the depth of 5mm under the brain surface) was usually 0.6 degrees C lower than the rectal temperature during HT period. The regional CBF increased from 38.1 +/- 6.5 (mean +/- SD) to 49.1 +/- 9.8ml/100 g/min by raising rectal temperature, and it recovered to a normal value after cooling. The ICP increased from 10.3 +/- 4.2 to 16.8 +/- 3.4 mmHg by raising rectal temperature, and it returned to a normal value after cooling. Brain tissue pH decreased from 7.33 +/- 0.02 to 7.17 +/- 0.09 rapidly when the rectal temperature reached 41.0 degrees C, and then returned to a normal value gradually after the start of cooling.(ABSTRACT TRUNCATED AT 250 WORDS)

[Experimental brain tumor in adult mongrel cat].

Small animal models such as the rat have serious limitations for multiple human scale instrumentation, surgical manipulations, and computerized tomographic (CT) evaluations, so that large animal models are required for the study using them. Although brain tumors induced with Rous sarcoma virus in neonatal beagle or adult monkey had been reported, these animals are very expensive ones for tumor research. A major drawback of virally induced brain tumor model is, moreover, the need for specialized viral facilities and safety precautions for laboratory personnel. In this paper, a cat glioma model implanted with C6 glioma cells derived from rats injected with N-nitrosomethylurea is reported. For an implantation dose of 5 x 10(5) cells/50 microliters, C6 glioma cells were suspended in modified Eagle medium supplemented with 10% fetal bovine serum and 0.5% agar. Twenty adult mongrel cats were injected with 5 x 10(5) C6 glioma cells intracerebrally. Implanted cats had brain tumors of about 10 mm in diameter with a yield of 80%. The mean survival was about 3 weeks after implantation. Tumors developed as spheroidal, hemorrhagic masses with central areas of necrosis and peripheral edema. They were located within the parenchyma of the implanted region. This tumor possessed many of the histological and radiological characteristics of human glioblastoma such as the following: Areas of hemorrhage and necrosis surrounded by pseudopallisading were observed within the tumor consisting of spindle-shaped cells with pleomorphic nuclei. A mass lesion with ring or garland-like enhancement surrounded by brain edema was shown on the CT scans.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood-brain barrier disruption caused by impairment of cerebral autoregulation during chronic cerebral vasospasm in primates.

Impairment of the cerebral autoregulation and its effects on the development of brain oedema during chronic cerebral vasospasm after subarachnoid haemorrhage (SAH) were studied in primates. The unilateral induction of SAH by clot placement around cerebral arteries produced a moderate degree of vasospasm (more than 40% reduction of vessel caliber on angiogram) seven days after SAH. Abolishment of autoregulation was observed in the territories of the cerebral hemisphere supplied by the vasospastic arteries. It was found that in this region an increase in cerebral perfusion pressure easily produced a marked elevation of the cerebral blood flow over the upper limit of autoregulation threshold resulting in disruption of the blood-brain barrier.

[Histological study of malignant cerebral granular cell tumor].

Granular cell tumor (GCT), which is suspected to be of Schwann cell origin, sometimes grows in the subcutaneous tissue, oral cavity and visceral sites and this tumor has a rather benign nature. Intracranial GCT also grows in the neurohypophysis but rarely in the brain parenchyma. We reported a case of intra-cerebral GCT in the left hemisphere, which took a malignant course. The patient was a 62-year-old male with a history of slowly progressing right hemiparesis and aphasia since May 1986. He was in a drowsy state and showed right hemiplegia on admission (October 14, 1986). Radiological examinations revealed a tumor and surrounding edema in the left temporal lobe and basal ganglia . Resection of the tumor and both radiotherapy of 53 Grey and chemotherapy using ACNU (total 310 mg) and BrdU (500 mg, two times per week prior to radiation) were applied after the operation. Although the tumor disappeared once after these treatments, the patient died of recurrence on July 3, 1987. Histological examinations on the specimen taken at the first operation revealed that the tumor consisted of rather round, large and small cells with a few cell processes. The large cells often had bizarre and multiple nuclei. These large cells had rich eosinophilic granular particles of various size and vacuoles in their cytoplasm. The staining for antiglial fibrillary acidic protein (GFAP) was positive in a part of the cytoplasm and cell processes. Electron microscopically various sized and shaped granular structures and intermediate filaments were noticed in the cytoplasm of both large and smaller cells.(ABSTRACT TRUNCATED AT 250 WORDS)