CT and arteriographic comparison of patients with transient ischemic attacks--correlation with small infarction of basal ganglia.

200

107

SUMMARY Three hundred and fifty-two patients with atherosclerotic middle cerebral artery stenosis (MCAS, 53%) or occlusion (MCAO, 47%) have been systematically studied. The study involved all patients entered into the EC/IC Bypass Study with isolated MCA disease or a tandem lesion predominating in the MCA ipsilateral to the ischemic events (18 patients with a tandem lesion of greater magnitude in the internal carotid artery were not included). The Asian patients represented 58% of all Asians entered into the EC/IC Bypass Study, whereas the white patients represented 18% of all whites and the black patients 34% of all blacks. Isolated TIAs were less frequent in MCAO (12%) than in MCAS (34%). Warning TIAs before a stroke occurred in one third of the cases. Presentation with stroke or isolated TIA was not influenced by sex, age, level of MCA obstruction, collateral circulation nor associated carotid disease. In MCAS, no major difference in presentation was found between severe and moderate stenosis. Pure motor hemiparesis occurred in 15% and pure sensory stroke in 2% of the patients with stroke and 30% of the MCA territory infarcts were small and limited to the lentkulocapsular area, confirming that so-called lacunar infarcts may be due to large vessel disease.During follow-up (42 months) of 164 medically-treated patients, further cerebrovascular events (TIA and stroke) occurred in 11.7% of the patients per year. In MCAO the stroke rate was 10.1 % per patient-year and the ipsilateral infarct rate was 7.1% per patient-year. In MCAS, the stroke rate was 9.5% per patientyear and the ipsilateral stroke rate was 7.8% per patient-year. The location and severity of lesion did not influence the occurrence of ipsilateral ischemic events during follow-up. Reopening of an artery-to-artery embolic occlusion of the MCA, with subsequent embollc reocclusion, may explain some of the ipsilateral ischemic events during follow-up. The annual death rate was 3.3% in MCAS and 2.6% in MCAO. Less than 15% of the survivors were severely disabled at the end of follow-up and nearly two-thirds were able to resume previous activities both hi MCAO and MCAS. The type of delayed ischemic events tended to be the same as that of the presenting event, but no factor could significantly predict the occurrence of stroke or death. This study suggests that long-term prognosis of patients with MCA occlusion, who present with TIA or non-devastating stroke, is reasonable.

Section: Discussionmentioning

confidence: 85%

Atherosclerotic disease of the middle cerebral artery.

Bogousslavsky¹,

Barnett²,

Aj³

et al. 1986

200

107

“…In the other three patients (1, 7, and 8), a hemodynamic mechanism cannot be definitively dismissed because of the timing of arteriography but a hemodynamic mechanism seems unlikely since distal occlusions in TIAs are notoriously rare. 2 More likely, the asymmetries resulted from a local vasoparalysis, 36 which would therefore be the most frequent mechanism of hyporeactivity we observed.…”

Section: Discussionmentioning

confidence: 87%

SPECT study of cerebral blood flow reactivity after acetazolamide in patients with transient ischemic attacks.

Chollet

Celsis

Clanet

et al. 1989

We investigated 15 patients with one or more transient ischemic attacks (TIAs) hi the internal carotid artery territory within the month following the most recent TIA. Cerebral blood flow (CBF) was measured by single-photon emission computed tomography, using intravenous xenon-133 before and after injection of 1 g acetazolamide. Six patients had severe carotid stenosis or occlusion; the other nine patients had no significant carotid lesions. Twenty age-matched volunteers free of neurologic symptoms or history were used as controls. Mean CBF in the sylvian region was not significantly different between patients and controls. Seven patients exhibited a focal hypoperfusion at rest in the symptomatic hemisphere, and their hypoperfused areas were hyporeactive after administration of acetazolamide. Seven other patients exhibited hyporeactive areas after acetazolamide administration while their CBF tomograms at rest were normal. Thus, CBF abnormalities were detected in 14 of the 15 patients. Our findings suggest that CBF measured early after acetazolamide administration could be useful to confirm the clinical diagnosis of TIA. In the nine patients with no significant lesion of the internal carotid artery, the areas of hypoperfusion were small and were probably related to the focal ischemic event. In the six patients with severe lesions of the internal carotid artery, abnormalities were of variable size and intensity but were often large and pronounced. The discrepancy between these two subgroups of patients could be ascribed to the hemodynamic influence of the internal carotid artery lesions. Moreover, our findings may provide some insight into the pathophysiology of TIAs. Received September 21, 1987; accepted September 27, 1988. has shown increased hemodynamic disturbance in some patients with cerebrovascular disease. This test has been used in patients with occlusion of the internal carotid artery (ICA) who suffered a minor or severe stroke and has shown changes in the perfusion reserve before and after extracranialintracranial bypass. 8 The purpose of our work was to study CBF reactivity after administration of acetazolamide in patients with TIAs and to analyze the findings in relation to CT and angiography results. We measured CBF by single-photon emission computed tomography (SPECT) before and after administration of acetazolamide in 15 patients with recent TIAs of various etiology. We assessed the regional vasodilatory capacity of the cerebral vessels and the influence that the ischemic lesions and ICA lesions exerted on it. Subjects and MethodsWe studied 15 patients (13 men, two women) with one or more TIAs in the sylvian or ophthalmic by guest on May 11, 2018 http://stroke.ahajournals.org/ Downloaded from

“…14 -20 - 22 However, in the clinical studies diagnostic criteria have varied. Some studies included patients with the CT finding of subcortical infarction that was not clinically associated with a lacunar syndrome.…”

Section: Discussionmentioning

confidence: 99%

“…1421 - 22 In other clinical studies, the presence of a cortical infarct was not excluded. 20 Also, selection criteria for angiography were not specified.…”

Section: Discussionmentioning

confidence: 99%

Clinical and radiologic features of lacunar versus nonlacunar minor stroke.

Norrving

Cronqvist

1989

We determined the angiographic presence of extracerebral and intracerebral arterial disease in 122 patients with minor stroke within the carotid territory; we excluded patients with a recognized cardiac source of emboli. Based on clinical features and computed tomographic findings, patients were classified as having lacunar infarcts (n=61), nonlacunar infarcts (n=53), and infarcts of indeterminate type (n=8). Severe carotid bifurcation disease (>50% stenosis or occlusion) was significantly more common in nonlacunar than in lacunar infarcts, on both the ipsilateral (p<0.001) and the contralateral (p<0.01) sides; 79% of the patients with nonlacunar infarcts had severe carotid bifurcation and/or middle cerebral artery disease on the ipsilateral side compared with 3.3% of the patients with lacunar infarcts. Our data underscore the need for classification of patients by the underlying mechanisms in future studies of treatment of ischemic stroke. (Stroke 1989;20:59-64) T ransient ischemic attacks (TIAs) are well recognized as a risk factor for the development of stroke. Patients with minor stroke have a similar risk for further neurologic deterioration 1 but have only rarely been singled out for detailed study. The desirability of establishing the pathogenesis of the cerebral ischemic event has been emphasized in recent reviews.2 -4 A stroke patient should ideally be characterized by the clinical signs and symptoms, by the localization and extent of infarction, and by the underlying vascular abnormality. Whereas in TIA patients the signs and symptoms have usually resolved by the time the patient is seen by a physician and the computed tomogram (CT scan) is most often normal, patients with minor stroke usually can be more fully characterized in these respects.In clinical practice the classification of patients into groups with ischemia due to large-vessel versus small-vessel disease is often difficult but of obvious importance. Large-vessel disease commonly affects the carotid bifurcation, and the ischemic symptoms are caused by artery-to-artery embolism alone or in combination with hemodynamic impairment. 2 -5 Small-vessel disease (lacunar infarction) in the anterior circulation localized to the basal ganglia and adjacent structures is caused by primary disease in the penetrating arterioles and is associated with lacunar syndromes, of which pure motor hemipareFrom the