The prognosis of intraventricular hemorrhage (IVH) differes among patients with similar volumes of intraventricular hematoma. We hypothesized that the prognosis of IVH is poor when the decrease in cerabral blood flow (CBF) lasts for a long duration as a result of severe global ishemia, mainly due to an instant rise in intracranial pressure at the time bleeding. To mimic the clinical condition of IVH with a prolonged decrease in CBF, we subjected rats to intraventricular blood administration combined with bilateral carotid artery occlusion (BACO). In order to attain long-lasting but nonlethal hypoperfusion within the brain, we ligated the right and the left caroitd arteries at a 7-day interval, and found that over 90% of the rats immediately became active on recovery from halothane anesthesia and that all of these rats survived At one hour after completion of BCAO, only active rats were anesthetized again and subjected to intraventricular injection of 40 μ1 of non-heparinized autologous blood. Forty-five percent of the rats remained lethargic and died within 16 hours following the surgery, as a result of severe brain edema. In contrast, all surviving rats exhibited no significant brain edema following intraventricular blood injection only, BCAO only, or intraventricular saline injection combined with BCAO. These findings suggest that fatal brain edema is oftern induced when IVH is accompanied by a moderate but long-lasting decrease in CBF.

View full abstract

We studied the relationship between the behavior patterns observed before the onset of cerebrovas-cular disease (CVD) and the type A behavior pattern in 46 CVD patients. The survey was devised by selecting 16 questions from the "Japanese coronary-prone behavior pattern scale" and a "Brief questionnaire for behavior pattern survey". The CVD patients were asked to describe their lifestyles prior to the onset of CVD. The results obtained may be summarized as follows. (1) Twenty-five (54.5%) of the CVD patients and 20 of 42 controls (47.6%) were judged to be of type A. There was no statistically significant difference in the ratio of type A personality between the CVD and control groups. However, the mean type A score in the CVD patients tended to be higher than that in the controls. (2) Factor analysis was carried out, with 20 items and 3 factors being selected: Factor I=job-involvement and competitiveness; Factor II=impatience, feeling of being pressed for time; and Factor III=methodical ness, punctuality. (3) The factor scores for Factors I and II were significantly higher in the CVD patients than in the controls. These observations implied that the CVD patients were enthusiatic workers who were strongly competitive, felt pressed for time, and tended to be quite impatient before the onset of CVD. These characteristics are common in type A behavior. There was no significant difference in Factor III factor score between the two groups. It is possible that being methodical and punctual is a common personality trait among Japanse people and it could not be inferred that this sort of behavioral tendency was particularly strong prior to the onset of CVD. The results of the present study suggested a correlation between the type A behavior patterns and the characteristics of the behavior patterns of CVD patients prior to the onset of the disease.

View full abstract

We investigated 17 patients suffering from single unilateral brain stem infarction (in the midbrain in 2 patients, in the pons in 9, and in the medulla in 6) to elucidate their remote cerebral and cerebellar blood flow changes. Regional cerebral blood flow was evaluated semiquantitatively by SPECT and ^99mTc-HMPAO, and the asymmetry index was calculated in certain regions of the cerebral cortex and cerebellum. A decreased cerebral blood flow was noted in 7 patients with infarction involving the dorsal brain stem, ipsilateral hypoperfusion occurred in patients with lesions situated rostrally to the upper pons, and contralateral hypoperfusion occurred in patients with lesions situated caudally to the upper pons, due probably to interruption of the cerebellothalamocortical pathways or damage to the fibers of the ascending reticular activating system. A decreased cerebellar blood flow was noted in 6 patients with infarction involving the ventral brain stem or cerebellar peduncle, contralateral hypoperfision occurred in patients with lesions situated rostrally to the middle or lower pontine basis, and ipsilaleral hypoper-fusion occurred in patients with lesions in the meddula, suggesting damage to the corticoponetocerbellar or olivocerebellar pathways. Although cerebral hypoperfusion evident only within 1 or 2 months after stroke cerebellar hypoperfusion was commonly demonstrated at several months after stroke. Remote cerebral and cerebellar blood flow reductions are commonly observed in brain sterm infarction, probably associated with lesions of the projectional fiber tracts.

View full abstract

Loss of motivation is frequently recognized in poststroke patients, and it disturbs rehabilitation and recovery in activities of daily living. We evaluated the reliability and validity of the Japanese version of Starkstein's Apathy Scale and compared the scale with an objective assessment (SKETCH Scale) in 135 poststroke patients. The Japanese Apathy Scale displayed a high reliability (ρ=0.963; p<0.0001, n=20) and validity (sensitivity, 81.3%; specificity, 85.3%) with a cutoff point of 16. When compared with the SKETCH scale, the scale also showed a high sensitivity and specificity. The distribution of the Apathy Scale with grade of objective scale revealed a significantly high correlation with the severity of motivational loss and emotional disturbance. Moreover, the score for the Apathy scale and the total scores for the objective assessment were significantly correlated to motivational loss and emotional disturbance. We concluded that the Japanese version of Apathy Scale is reliable and valid for making clinical assessments and is useful for evaluating mild motivational impairment in stroke patients.

View full abstract

Early detection and prophylactic clipping for unruptured cerebral aneurysms are expected to improve the overall outcome of aneurysm management. However to prevent surgical complications coating operations are selected in a few cases. The aim of the persent study was to clarify the clinical significance of reinforcement 53 aneurysms (43 cases) were analyzed (anterior circulation, 48; posterior circulation, 5). Aneurysms treated with clipping only amounted to 39 (73.6%), while an incomplete clipping and coating method was chosen in 3 aneurysms, and coating with cyanoacrylate glue (Biobond^® and Oxycell^® in 7 (14%.3%). Late rupture was noted in a basilar tip aneurysm with incomplete exposure or the aneurysmal sac treated by a coating operation. Permanent neurological deficit was demonstrated in 2 patients (hemiparesis following clipping, 1; husky voice following coating, 1). These results suggest the importance of adequate coating for unclippable unruptured aneurysms and the surgical choice of treatment at exploration.

View full abstract

The subjects studied included 205 normal controls, 22 patients with dementia of the Alzheimer type (AD) and 22 patients with vascular dementia (VD). A noninvasive technique was adopted in the present study, and a near-infrared cerebral oximeter (1 N VOS-3100 Cerebral Oximeter; Somanetics Co., Ltd.) was set up on the forehead to measure the absolute value of the regional oxygen saturation (rSO₂).
In the normal control group, no difference was recognized between the rSO₂ levels measured on the right and left sides. The average rSO₂ level was calculated for each generation, from the twenties to eighties, and the results were compared among them. Although there was salight upward trend with increase in age no significant differences were noted between the average rSO₂ level of those in their twenties and the average levels of older generations ranging from their thirties to seventies. The average rSO₂ level of those in their eighties was significantly higher than that of those in their twenties. In view of the structural principle employed in this oximeter, increases in cerebral blood flow or decreases in cerebral metabolic rate of oxygen probably contributed to this increase in rSO₂ because the values for the hemoglobin and saturation of arterial blood oxygen (SaO₂) were normal. It is a well-known fact that an increase in age is associated with a decrease in cerebral blood flow. There is a good possibility therefore that decreases in cerebral metabolic rate of oxygen induced this phenomenon.
The average rSO₂ level in AD was significantly higher than that of the aged normal controls. The average rSO₂ level in VD was significantly lower than that of the aged normal controls. These findings suggested that a decrease in cerebral metabolic rate of oxygen affected the frontal lobe more significantly than did a decrease in cerebral blood flow m the AD group, and that a decrease in cerebral blood flow affected the frontal lobe more significantly than did a decrease in cerebral metabolic rate of oxygen in the VD group. In conclusion, measurements of rSO₂ can be performed noninvasively and easilyat the bedside, and the results obtained can be used as indices for the cerebral circulation and metabolism.

View full abstract

Cerebral blood flow was measured by the ¹²³I-IMP-autoradiographic (ARG) method, which required one-point arterial blood sampling and acquisition of a single atatic-scan, in 43 patients with silent brain infarction (SBI) and compared with that in 36 healthy subjects and 39 patients with lacunar infarction (LI). The mean cerebral blood flow (mCBF) in SBI was 34.6 ± 6.2ml/100g/min, while the values of mCBF in healthy subjects and LI were 36.2 ± 6.2 ml/100g/min and 30.2 ± 4.4 ml/100g/min, respectively. There was no significant difference in mCBF between the healthy subjects and SBI. The patients with LI had a lower mCBF as compared to that of the healthy subjects or SBI. In the three groups, women showed higher mCBF values than did men. At all regional sites, no significant differences in rCBF were found between the healthy subjects and SBI. The patients with LI, on the other hand, demonstrated significantly lower rCBFs in all regional sites except for the left upper frontal lobe, as compared to those in SBI. The observed dissociations in cerebral blood flow between SBI and LI-imply that the pathophysiology of silent brain infarction does indeed differ from that of symptomatic lacunar infarction.

View full abstract

The cost effectiveness of conventional acute cerebral thrombosis treatment and conventional treatment plus antithrombin treatment using Argatroban was analyzed on the basis of double-bland test data comparing Argatroban (group A) with a placebo (group P). In this analysis, the longest admission term was 90 days, and effectiveness was defined as the decreased number of days of admission. Direct cost alone and direct indirect cost were examined retrospectively.
The results obtained showed that the value anticipated for days remaining (90 days-days of admission: E) after discharge and cost (direct cost: DC; direct cost + indirect cost DC + IC) per patient averaged 56.2 days-DC 1, 035 thousand yen, and DC + IC 1, 558 thousand yen in group A, and 35.9 days-DC 1, 261 thousand yen, and DC + IC 1, 740 thousand yen in group P. The days of admission were fewer in group A than in group P by an average of 20.3 days; DC was estimated to have been reduced by 226 thousand yen and DC + IC by 182 thousand yen. The average cost per remaining day (C/E) was lower in group A than in group P for both DC and DC + IC, indicating that the Argatroban-supplemented treatment was more cost-effective than the placebo treatment. Treatment in which Argatroban is added to the treatment in group P (group A) is more effective and less costly than the treatment in group P, i. e. ΔC/ΔE is minus. Argatroban was thus verified to be useful both in terms of clinical effectiveness and from the economic viewpoint in medical treatment.

View full abstract

Since negative results have been obtained in international bypass studies, the criteria for STA-MCA anastomosis remain uncertain. Cerebral hemodynamic research can facilitate the identification of a small subgroup. In the present study, STA-MCA anastomosis was performed in criteria were based on the cerebral hemodynamics (that is a decreased CBF and increased OEF on PET study) and also on the general condition of the patient. As a result, no perioperative complications were encountered. The hemodynamics tended to recover. There were no patients who suffered further episodes of brain ischemia during the follow-up period. In conclusion, STA-MCA anastomosis is considered to constitute an appropriate therapy for patients selected on the basis of their hemodynamics and general condition.

View full abstract

We have demonstrated previously that mild hypothermia (33°C) can disturb cerebrovascular autoregulation in awake rats. However, some investigators believe that hypothermia disturbs cerebrovascular autoregulation only in a pH-stat condition and hypercapnia is the major cause of the disturbance. The aim of the present study was to examine the effects of severe hypothermia on cerebrovascular autoregulation and on the response of the pial arteries in anesthetized rats. Twenty-four male Wistar rats (300-350 g) were anesthetized with 0.7% halothane and O₂/N₂O (30/70%) initially, followed by a-chloralose under mechanical ventilation. The animals were divided into 4 groups; i.e., a normothermic group (37.0±0.5°C; n=6), and three hypothermic groups (31.0±0.5±, n=6; 27.0±0.5°C, n=6; and 25.0±0.5°C, n=6). The brain and rectal temperatures were both controlled at the desired levels by using a thermocontrolled pad and ice-cold water, respectively, in all groups. Arterial blood gases were controlled by mechanical ventilation and monitored with a pH-stat. The mean arterial blood pressure (MABP) was lowered by exsanguination at a rate of about 10 mmHg/min and maintained at the desired level for at least 2 min before making measurements. The pial vasculature was visualized through a closed cranial window (dura removed) which was implanted in the right parietal bone. The cortical regional cerebral blood flow (CBF, DF) was measured continuously with a laser-Doppler flowmeter. The pial vessel diameter (30-60μm pial arteries) was determined with a CCD camera. Although the caliber of the pial vessels was not significantly altered in the hypothermic normotensive condition, CBF_LDF decreased significantly with decrease in the intracranial temperature, possibly due to flow-metabolism coupling. Cerebrovascular autoregulation, which was assessed in terms of the change in CBF_LDF with decrease in MABP, was abolished in all of the hypothermic groups. Surprisingly, the pial arteries were significantly contracted at an MABP level of 40 mmHg in the severely hypothermic (25.0°C) group. These findings suggest that cerebrovascular autoregulation and arterial responses were abolished under various hypothermic conditions. There are several possible mechanisms for the inpairment of cerebrovascular autoregulation occurring in severe hypothermia. We speculate that severe hypothermia may influence autonomic function through modulation of neurotransmitter release, since some previous studies have suggested that changes in brain temperature can inhibit the release of serotonin and endothelin-1. Alternatively, severe hypothermia could reduce nitric oxide production. We believe that our observations have important implications for surgical operations, including cardiopulmonary bypass, and for the hypothermic treatment of patients with cerebral damage.

View full abstract

We report the case of a 78-year-old woman with progressive loss of visual acuity in the right eye attributable to right internal caroid artery and ophthalmic artery stenosis before carotid endarterectomy. In the previous year, she had suffered recurrent episodes of transient left band numbness three times. In the current year, she had experienced numbness of the left hand and weakness of the left upper extremity caused by cerebral infarction. Two months later, she suddenly suffered loss of right visual acuity. This loss or acuity was progressive and a diagnosis of ischemic ocular syndrome was made. After one month, she was admitted to our hospital. Cerebral angiography disclosed 70% stenosis at the bifurcation of the right internal carotid artery and external attery, 90% stenosis at the rogin of the right internal caroid artery with ophthalmic artery stenosis and 50% stenosis at the origin of the right external carotid artery, the patient experienced no transtent ischemic attacks but her visual disturbance remained unchanged. Although it is well knwon that ischemic oculopathy can be caused by an opthalmic artery steal phenomenon resulting from internal carotid artery occlusion, the present case may have been due to ophthalmic artery stenosis.

View full abstract

A 48-year-old man was admitted to our hospital following several attacks of transient diplopla, numbness and loss of consciousness. T2-weighted MRI demonstrated multiple small high signal lesions in the left thalamus and pons. He was diagnosed as having cerebral infarction. Cerebral angiography cerealed "strings of beads"-like shadows in the bilateral intracranial vertebral arteries. These observations met the criteria of cervicocephallc arterial FMD. No abnormal anglographic findings were found in the renal artery. It appeared that thromboembolic TIA and cerebral infarction had been caused by intracranial FMD in this case.

View full abstract