Among patients who were admitted to our hospital with a suspicion of cerebrovascular disease, we selected patients with cerebral thrombosis and cerebral embolism. All patients were serial cases and the diagnosis was made as follows. Cerebral embolism was finally confirmed by neuroradiological examinations; namely patients showed massive hemorrhagic infarction sign on CT or massive low density area with no occlusive findings of corresponding arteries on crebral angiogram or abrupt occlusion of main arteries due to the plugging of embolus with no sclerotic change in the surrounding arteries seen on angiogram. Heart diseases such as atrial fibrillation and myocardial infarction are generally thought to be important factors for the diagnosis of cerebral embolism, but their existence was not taken into consideration for the diagnosis of embolism in this study. Cerebral thrombosis was also confirmed by neuroradiological evaluation; low density area including lacunes on CT with sclerotic change on corresponding cerebral angiogram. There are 79 cases of thrombosis and 21 cases of embolism. Mean age at onset is 65.9 on thrombosis and 68.3 on embolism and there was no statistic significance between these two groups.
Alcohol drinking was more frequently observed in cases of embolism than in cases of thrombosis. On EKG, atrial fibrillation was more frequently observed in embolic patients than in thrombotic patients, although high R in V₅is predisposed to thrombosis. Neurologically, conjugate deviation of the eyes and aphasia as well as agnosia were more frequently seen in patients with embolism. Statistically significant laboratory data examined on admission between these two groups were serum total protein (thrombosis group 6.96±0.73, embolim group 6.38 ± 0.68, p<0.01), serum albumin (4.05 ± 0.48, 3.63 ± 0.45, p<0.01) and serum total cholesterol (193 ± 41.5, 158 ± 42.5, p<0.01). We conclude from these laboratory data that patients with cerebral embolism in Akita (northern part of Japan) are more likely exposed to insufficient nutrition than patients with cerebral thrombosis and that was acceleratd by the habit of alcohol drinking.
Epidemiological study among Japanese done before the introduction of CT had revealed that lower total cholesterol levels reflecting the low fat intake might be one of the factors for developing of cerebral hemorrhage.
But type specific diagnosis was very difficult at that time.
We also conclude that among patients who were rated as cerebral hemorrhage, there might be some patients who should be diagnosed as cerebral embolism.

View full abstract

Clinical features of basilar artery embolism in 3 cases are reported. The incidence of basilar artry embolism was 0.48% in 631 cases of cerebral infarction and 2.7% in 113 cases of cerebral embolism.
The initial symptom of our 3 cases was sudden onset of coma without any prodromal symptoms. Neurological examination revealed abnormalities of light reflex and corneal reflex, disturbance of eye movements, quadriplegia, decerebrate rigidity and autonomic dysfunctions. Moreover, the prognosis was so poor that the 3 cases died of complications 53, 80, and 25 days after the onset. Basilar artery embolism is considered to be the most serious in every cerebral infarction and followed by various neurological symptoms, which make it quite difficult to be diagnosed definitely.
Therefore, it seems to be important to study the clinical features of basilar artery embolism in detail.

View full abstract

Effect of long term administration of eicosapentenoic acid (EPA) in stroke-prone spontaneously hypertensive rats (SHRSP) was studied. Survival, plasma lipid and endothelium of middle cerebral arteries (MCA) were investigated after administration of EPA for 25 weeks. Effect of EPA on acutely-induced cerebral ischemia was also studied. Eicosanoids play an important role in development of arteriosclerosis and occurrence of cerebral ischemia. EPA suppreses platelet aggregation and inhibits arachidonate conversion into thromboxane A₂and other prostaglandins. EPA is also itself oxidized by cyclooxygenase and lipoxygenase, and TXA₃ and LTB₅ derived from EPA show less potent biological actions compared to TXA₂ and LTB₄from arachidonate. Therefore administration of EPA might reduce development of arteriosclerosis and the brain damage from ischemic insult. The objective of this study is to investigate the effect of EPA on brain edema and metabolites in cerebral ischemia.
Eight weeks old male SHRSP were used for experiment. SHRSP were fed either a standard diet (control) or a diet supplemented with EPA (100 mg/kg/day) for 25 weeks. At 33 weeks old, plasma lipids were analyzed and luminal surfaces of MCA were investigated using scanning electron microscopy (SEM). In the same aged rats, cerebral ischemia was induced by bilateral common carotid artery occlusions (BLCO), and brain edema and metabolites (ATP, lactate, pyruvte) were determined 3 hr after BLCO.
In total plasma fatty acid composition, eicosapentaenoate (20:5) increased in the EPA administrated group, while the level of arachidonate (20:4) were not changed. In the SEM observation of MCA, a lot of microvilli, hypertrophy of marginal folds, shrinkage of endothelium and RBC trapped by fibrin nets were observed in the control group. While these degenerative changes were slight in the treated group. In the experiment of cerebral ischemia, brain water content in the EPA group was significantly lower and pyruvate was higher than in the control gorup, while there were no differences in the levels of ATP and lactate between the both groups.
These findings indicate that administration of EPA reduces ischemic damage, especially brain edema as well as degenerative changes of endothelium in non-ischemic SHRSP through influence on arachidonate metabolism.

View full abstract

A 62-year-old man was admitted to our hospital because of repeated TIA presenting with vertigo, diplopia and perioral numbness. He had a history of brain stem infarction with an occlusion of the left vertbral artery four years prior to the prsent attacks, and had been receiving antiplatelet agent since then. He was hypertensive (178/100 mmHg) and obese, and appeared to be anemic. After admission, a gastroscopic examination revealed the presence of multiple erosive polyps of the stomach which was thought to be the cause of severe iron deficiency anemia (hemoglobin : 7.2 g/dl). Severe stenosis of the right vertebral artery was also demonstrated by right brachial angiography. During admission, TIA recurred frequently when blood hemoglobin decreased below 9.0 g/dl or hematocrit below 30%. Ater polypectomy, TIA ceased to occur accompanied by the recovery of anemia even without using antiplatelet agent.
In reviewing the clinical course of this patient, it is evident that the prsence of severe anemia accelerated the occurrence of hemodynamic TIA because of reduced oxygen transport capacity of the blood. For management of TIA, careful observation of underlying medical disorders is important as well as the exploration of vascular diseases.

View full abstract

A case of saccular aneurysms of the posterior inferior cerebellar artery and anterior inferior cerebellar artery associated with arteriovenous malformation is presented. The arteriovenous malformation was fed by superior cerebellar artery and posterior inferior cerebellar artery. The arteriovenous malformation was totally extirpated and the anterior inferior cerebellar artery aneurysm was clipped in two-stage operations. The posterior inferior cerebellar artery aneurysm decreased its size after the operation. The association of arteriovenous malformation and arterial aneurysm in the posterior fossa is reviewed.

View full abstract

We studied the clinical features of late convulsive seizure which occurred more than two weeks after cerebral infarction. Subjects were 43 patients (26 males, 17 femles) aged from 45 to 83 years old (mean ± S.D. : 67 ± 10 years). Cerebral infarction was confirmed with either computed tomography or magnetic resonance imaging, and electroencephalography was performd within 72 hours after the convulsive seizure.
The inteval between the cerebral infarction and the seizure ranged from one month to nineteen years. Twelve patients (28%) had seizures within one year and 21 patients (49%) had them within two years after cerebral infarction.
The locations of cerebral infarction in 24 patients (58%) were in the cortical branch territory of the middle cerebral artery. The patients who had had cerebral infarctions in the territories of the middle cerebral artery along with the anterior or posterior cerbral arteries amounted to 79% of the subjects. The cerebral infarction was located in the perforator branch territory of the middle cerebral artery in 5 patients. None of the subjects had cerebral infarction located in either the brain stem or the cerebellum.
The numbers of patients who had risk factors of cerebral infarction were as follows; 25 patients with hypertension, 8 with diabetes mellitus, 2 with atrial fibrillation, and 2 with ischemic heart disease.
Late convulsive seizure occurred during the three months of November, December and January in 16 patients, although only four patients had convulsion during the three months of June, July and August.
Regarding the type of convulion, 21 patients showed generalized convulsive seizures and 18 showed focal or secondary generalized seizures.
On the electroencephalogram, 23 patients (54%) showed either sharp waves or spike waves, and 17 (40%) showed focal slow waves. Only two patients showed diffuse slow waves and one revealed a normal EEG. The paroxysmal waves were more likely to be detected in either the posterior portion of the frontal lobe or the anterior portion of the parietal lobe.
Status epilepticus was observed in 17 patients (40%), being more likely to be occurred in elderly patients. Fifteen patients (35%) had recurrent convulsion, which was more common in patients who had had convulsion shortly after cerebral infarction.

View full abstract

A case of thromboangiitis obliterans associated with multiple cerebral aneurysms is presented.
A 69-year-old woman in coma was ambulated on April 4, 1989. She complained of severe headache and numbness of her right cheek the night before admission. She had been suffering from thromboangiitis obliterans since she was 38 years old, which was angiographically diagnosed at her age of 58. Computed tomogram of the head revealed a subarachnoid hemorrhage with intracerebral hematoma in the left temporal lobe. Left carotid angiogram revealed two saccular aneurysms, located in the middle cerebral artery and the distal anterior cerebral artery and the severe stenosis of the middle cerebral artery and the mild stenosis of C3 portion. On right carotid angiogram, the carotid stenosis at C3 portion was observed. Smooth tapering of the arteries in the cerebellar hemispheric region, implying the cerebral thromboangiitis obliterans was found on the vertebral angiogram.
Emergent operation was performed to clip the middle cerebral artrial aneurysm and to evacuate the hematoma. Her postoperative recovery was remarkable and she tolerated well the second operation for the aneurysm of the distal anterior cerebral artery 3 weeks later. She discharged on her feet with a minimal comprehensive aphasia.
The association of thromboangiitis obliterans and cerebral aneurysm is rare. The underlying mechanism of this rare association was considered the mere coincidence but might be postulated to be derived from the common cause of the collagen abnormality.

View full abstract

It is widely accepted that the prognosis of primary pontine hemorrhage depends on transverse and longitudinal diameters of the hematoma. However, no systematic evaluation has yet been attempted on the relation between the volume and direction of extension of the hematoma and vital prognosis of the patients. The present clinical study was aimed at investigating on these themes.
The subjects were 22 patients with primary pontine hemorrhage. Duration from the onset was 2.7± 5.2 hours (mean ± SD). On admission, 3 cases were in somnolence, 4 in stupor, 10 in semicoma and 5 in coma. Eleven out of the 22 cases died in 2.3 ± 4.3 days from the onset. The volume of the hematomas was calculated from CT scan image taken on the day of admission, and was classified in 3 groups; it wa smaller than 5 ml in 8 cases (Group I), 520 ml in 10 (Group II) and larger than 20 ml in 4 (Group III).
All of the group I and 3 cases of the group II survived, while all of the group III and 7 cases of the group II died. Out of the 10 cases of the group II, three had hematomas extending toward cerebellum, and all of them died. Six cases of the group II had hematomas extending toward midbrain, and 3 of them survived although their hematomas were larger than those in the case with extension only toward cerebellum. In all of the group III, the hematomas extended toward both cerebellum and midbrain in addition to ventricular ruptures.
From the above data, vital prognosis is good in the patients with hematomas smaller than 5 ml, while it is absolutely poor in the cases with hematomas larger than 20 ml. With the hematoma between 5 and 20 ml, the possibility of survival is expected only in the cases with extension of hematoma toward midbrain.

View full abstract

We describe a 68-year-old female with persistent atrial fibrillation, who presented with characteristic ocular signs and akinetic mutism due to embolic occlusion of the basilar artery.
She was admitted to our hospital because of disturbed consciousness and immobility of the left extremities. After recovery of consciousness disturbance, she was apathetic and lack of spontaneity, and she was diagnosed as having akinetic mutism. Her left eye was slightly abducted, and right eye was mydriatic with corectopia.
Cerebral angiography examined at admission revealed occlusions of the right posterior cerebral artery and the right superior cerebellar artery at their origins. Follow-up angiography performed 22 days after admission showed reopening of the occulded arteries.
CT revealed low density area in the bilateral thalami and right cerebral peduncle. Moreover, MRI demonstrated low signal intensity areas restricted to the paramedian area of bilatral thalami and tegmentum of the midbrain by horizontal section, and characteristic butterfly-shaped lesion by coronal section.
We suspected that responsible lesions for the development of neurologic signs were present in the right nucleus of Edinger-Westphal, the left oculomotor nucleus, the rostral interstitial nucleus of MLF, and bilateral thalami. These lesions were caused by flow derangement of the paramedian thalamic artery due to embolic occlusion of the top of the basilar artery.

View full abstract

The intracranial dissecting aneurysms of the posterior circulation, which has been reported as very rare condition, are being reported in increasing number, seemingly due to enhancement of knowledge about the clinical and angiographic features of this disease. However, the number of the reported cases is not so many as expected; there must have been many more cases which were clincially unrecognized as such, and diagnosed simply as fusiform aneurysms or ischemic attacks.
The authors report six cases of this disorder, and review eighty nine cases of such disease in the literature, discussing especially its diagnostic aspect.
There were 4 males and two females, ranging in age from 30 to 56 years (mean 45.6 years). The dissection involved the vertebral artery (VA) in five cases, in one of which it extended up to the vertebro basilar junction, and posterior cerebral artery (PC) in the remaining one.
Pathologically, three cases might fall into the group I of Yonas in which the plane of dissection was between internal elastica and media, causing the lumen of the vessel norrowed or occluded and the remaining three into group II in which the dissection occurred within media and adventitia forming pseudoaneurysm.
Lumbar puncture revealed SAH in two cases. The onset was with severe headache and nuchalgia in all of this six cases. Four of them showed ischemic symptoms of brain stem, such as vomiting, dysphagia and Wallenberg's syndrome. In the remaining two cases the main symptom was those of SAH.
Angiography demonstrated “pearl and string sign” in three cases, “intramural pooling sign” in two, “rosette sign” in one and pseudoaneueysm in two cases.
Eighty nine cases in literature by Friedman, Shimoji, Berger and so on were reviewed, discussing especially the diagnostic signs. The dissecting aneurysm of he posterior circulation may be suspicious, when patients complain of severe headache or nuchalgia followed by ischemic symtoms of brain stem.
Out of the true angiographic signs of dissecting aneurysm, such as, “double lumiana sign”, “intimal flap”, and so on, “intramural pooling sign” may be most useful because it is commonly demonstrated. Fusiform aneurysms with narrowed segment of artery could be regarded as dissecting lesions.
It could be diagnosed even by the angiographic possible signs, if the clinical features of this disorder were referred.

View full abstract

Venous stasis retinopathy and ischemic oculopahy are less familiar ocular manifestations of cerebrovascular disease than amaurosis fugax. When the ischemic changes are limited to the posterior part of the eye, the condition is termed venous stasis retinopathy. If these changes spread and involve the anterior part of the eye, it is called ischemic oculopathy, which is thought to terminate in neovascular glaucoma.
In the present report, brain CTand cerebral angiograms in six male patients with venous stasis retinopathy and/or ischemic oculopathy were studied (age ranging from 41 to 68 with a mean of 56 years old).
Ocular symptoms in these patients were decreased visual acuity and episodes of transinet monocular blindness (amaurosis fugax) : two patients presented with decreased visual acuity alone, three had both decreased visual acuity and amaurosis fugax, and one (had) amaurosis fugax alone.
Brain CT showed subcortical small infarction (s) in four patients and no detectable lesions in the remaining two. In all six patients an occlusion of internal carotid artery ipsilateral to the affected eye was demonstrated in the neck by angiography. A rich collateral circulation to the brain was demonstrated through the ophthalmic artery in all but one patient.
It was suggested that blood supply to the eye ball was stolen because of this rich collateral blood flow to the brain, and that this “ophthalmic artery steal phenomenon” caused the venous stasis retinopathy. As four of six patients later developed neovascular glaucoma, repeated ophthalmologic examinations should regularly be performed in such patients with the internal carotid artery occlusion that have no or small infarctions on CT and good collateral circulation through the opthalmic artery to the brain.

View full abstract

To investigate secular trends in incidence of all stroke, cerebral hemorrhage and cerebral infarction in Japan, morbidity surveillance for men and women aged 40 yr and over was conducted in a northeast rural community between 1964 and 1984. Cross-sectional studies of risk characteristics for men and women were also performed in 1963-1966 and in 1972-1975. To determine risk factors of cerebral infarction, two cohorts of men and women aged 4069 were constructed in 1963-1966 (2, 221 persons) and in 1972-1975 (2, 574 persons) and followed until 1974 and 1984, respectively.
Age-adjusted incidence of all stroke, cerebral hemmorrhage, and cerebral infarction declined significantly in both men and women aged 4069 yr between 1964-1968 and 1979-1984 (p<0.01). Incidence of all stroke did not change significantly for men and women aged 70 and over because of no change in cerebral infarction in spite of a decrease in cerebral hemorrhage.
According to the Cox proportional hazard model, sex (men), age, diastolic blood pressure, and hypertensive and sclerotic changes in fundus were positively associated with incidence of cerebral infarction in early cohort. In later cohort, atrial fibrillation was related to incidence of cerebral infarction as well as sex (men), age, and diastolic blood pressure. Incidence of cerebral infarction was three times higher in persons with atrial fibrillation than in persons without it.
Population attributable risk of cerebral infarction was 42% for hypertension and 48% for funduscopic abnormality in early cohort. The attributable risk declined 40% for hypertension and 61% for funduscopic abnormality from early cohort to later cohort. This substantial decline in the attributable risk was mostly due to a decline in blood pressure levels by improvements of hypertension control and diet and environmental factors. For atrial fibrillation, population attributable risk of cerebral infarction was only 3% because of the low frequency of atrial fibrillation in the population.

View full abstract

We have reported previously that red blood cel aggregability (RBC-A) is enhanced in patients with cerebral infarction (Stroke 1989 ; 20 : 1202-1207). The purpose of the present study was to investigate RBC-A in patient with transient ischemic attacks (TIA). The subjects comprised 26 patients with an episode of TIA more than once in the past one year (21 males and 5 females, 56±8 YO) and 52 healthy human volunteers (56±8 YO). The TIA patients were divided into two subgroups according to their brain CT findings; group A, infarcted area on CT (-), N=19, group B, infarcted area on CT (+), N=7. RBC-A was measured using the whole blood RBC aggregometer developed by us (Am J Physiol 251 : H1205-H1210, 1986) with concomitant measurement of blood factors such as hematocrit, albumin-globulin ratio (A/G ratio) and fibrinogen. The RBC-A values in TIA (group A + group B), group A and group B were 0.142 ± 0.025/sec, 0.133 ± 0.022/sec and 0.163± 0.012/sec, respectively. These values were statistically significantly (p<0.01, p<0.05, p<0.05) higher than that of the control group (0.122 ±0.027/s). There was a statistically significant difference (p<0.05) in RBC-A between group A and group B. There were no statistically significant differences in the values of the hematocrit, A/G ratio and fibrinogen between TIA patients and controls. The above data suggests that enhanced RBC aggregability in TIA patients may reflect a precursor state of cerebral infarction from the standpoint of hemorheology.

View full abstract

A case presenting with unilateral drop hand was studied with CT scan and MRI, which showed a characteristic local cerebral infarction in the contralateral precentral gyrus 10 and 17 days after the onset.
The characteristic features of drop hand were reviewed, and differential diagnosis between peripheral radial nerve palsy and monoparesis due to a brain lesion was discussed. MRI would be promising in the diagnosis of small infarctions and in the understanding of the functional anatomy of the brain.

View full abstract