Dan Lindell

Lacunar Infarcts: A 1-Year Clinical and MRI Follow-Up Study

There are only a few reports on long-term prognosis and functional outcome after lacunar infarction, and little is known about the evolution of MRI abnormalities with time in this subtype of stroke. To address these issues, we performed a 1-year clinical and MRI follow-up study in 81 patients with presumed lacunar infarction. AT 1 year after stroke onset 1 patient had died, whereas 5 patients (6.2%) had had recurrent strokes. Based on the Oxford Handicap Scale, 63 (79%) of the surviving patients were functionally independent at the time of follow-up. MRI at 1 year revealed new, clinically silent infarcts in 8 patients (10%), and wallerian degeneration of the pyramidal tract in 8 (24%) of the 34 patients with posterior capsular or putamenal infarcts on initial MRI. Our data suggest that new, clinically silent infarcts may be at least as common as recurrent strokes in patients with lacunar infarctions.

Lacunar Infarcts: Functional and Cognitive Outcomes at Five Years in Relation to MRI Findings

Background: There are few long-term follow-up studies of patients with lacunar infarcts (LIs). The purpose of this 5-year follow-up study was to assess functional and cognitive outcome in relation to MRI findings. Methods: 81 patients with a first-ever LI were followed for 5 years with respect to mortality, stroke recurrence, functional and cognitive outcome. T2-weighted MRI was performed at baseline and at 5 years. The presence of basal ganglia lesions and white matter lesions was scored according to the European Task Force rating scale. Functional outcome was assessed with the Oxford Handicap Scale (OHP). Cognition was assessed with the Mini Mental State Examination (MMSE). Results: The 5-year mortality was 19%. Predictors for death were age (OR = 1.07, 95% CI 1.03–1.11), ischemic heart disease (OR = 2.1, 95% CI 1.1–4.1) and impairment score (OR = 1.16, 95% CI 1.02–1.32). 30% of the patients had a recurrent stroke. Predictors for recurrent stroke were diabetes mellitus (OR = 1.7, 95% CI 1.2–7.4) and amount of white matter lesions (OR = 1.7, 95% CI 1.2–2.7). 36% of the patients were functionally dependent (defined as OHP >2). Predictors for functional dependency were impairment score (OR = 1.71, 95% CI 1.12–2.59), MMSE (OR = 0.55, 95% CI 0.33–0.91) and stroke recurrence (OR = 84, 95% CI 9.4–745). 16% of the patients had cognitive impairment (defined as MMSE <24). Stroke recurrence and white matter score, but not basal ganglia score, were correlated to cognitive impairment. Conclusions: Many LI patients have a good functional outcome at 5 years. For older patients, for patients with an initial severe stroke, and with additional vascular risk factors, however, the prognosis is more severe, with an increased risk for mortality, stroke recurrence, and physical and cognitive decline.

Presumed Pathogenetic Mechanisms of Recurrent Stroke after Lacunar Infarction

We report presumed mechanisms of recurrent stroke in a prospective study on patients with lacunar infarction. Eighty-one patients with clinical and magnetic resonance imaging (MRI) findings compatible with lacunar infarction were followed for a median time of 48 months. Patients with recurrent stroke were assessed clinically by computed tomography, contrast-enhanced MRI and with respect to large-artery disease and cardioembolic sources of embolism. During follow-up, 9 patients (11.1%) died and 20 patients (24.7%) had 27 recurrent strokes (3 hemorrhagic, 24 ischemic). The annual risk of recurrent stroke was 6.8% and approximately even with time. Univariate analysis revealed age as the only risk factor significantly associated with recurrent stroke. Out of 24 episodes of recurrent ischemic stroke, 16 had clinical and neuroimaging features compatible with small penetrating artery occlusion, 6 were due to cortical infarcts, 1 episode was caused by presumed cerebral amyloid angiopathy, and 1 by a retinal infarct. Relevant large-artery disease was diagnosed in 2 patients with recurrent, small brainstem infarcts and in 2 patients with recurrent cortical and retinal infarcts. Although presumed lacunar infarcts predominated, our series highlights the heterogeneity of recurrent strokes after lacunar infarcts.

Sensory symptoms and signs and results of quantitative sensory thermal testing in patients with lacunar infarct syndromes.

Quantitative data on sensory impairment in stroke patients are limited. We measured the perception thresholds for temperature and thermal pain in patients with different lacunar syndromes, correlated the results with clinical and magnetic resonance imaging (MRI) findings, and studied the long-term prognosis of sensory dysfunction. Methods Quantitative thermal testing was performed by means of the Marstock method in 39 patients with lacunar syndromes (pure motor, sensorimotor, or pure sensory stroke) and MRI findings compatible with occlusion of a single perforating artery. Thresholds for cold, warmth, and heat pain were obtained bilaterally from the cheek, hand, and leg. The unaffected side was used as control. Follow-up included clinical assessments and repeated quantitative thermal testing (in 17 patients) up to 1 year after stroke onset. Results Patients with pure sensory stroke and sensorimotor stroke (n=22) had a significant thermal hypoesthesia on the affected side for all modalities and test locations. Patients with pure motor stroke (n=17) exhibited thermal hypoesthesia for cold and heat pain in the hand and for cold perception in the leg. On MRI, infarcts causing pure motor and sensorimotor stroke were predominantly lenticulocapsular, while a thalamic site of infarction was found in pure sensory stroke. The prognosis of sensory impairment was favorable, except for poststroke pain syndromes in three patients. Conclusions Quantitative thermal testing confirmed an involvement of spinothalamic pathways in lacunar infarcts causing pure sensory and sensorimotor stroke and revealed a subclinical sensory impairment in patients with pure motor stroke. Infarction sites were similar in patients with pure motor and sensorimotor stroke.

Gadolinium-Enhanced Magnetic Resonance Imaging in Patients with Presumed Lacunar Infarcts

To determine the clinical usefulness of gadolinium-DPTA-enhanced MRI in identifying recent small, deep infarcts we prospectively studied 91 patients with first-ever stroke and presenting with a lacunar syndrome. In 78 patients (85.7%), plain MRI revealed possibly appropriate infarcts, classified as deep (n = 69), internal borderzone (n = 1), and cortical (n = 8 patients). Enhancement was seen in 38 (80.9%) of 47 patients with only one possibly relevant deep lesion on plain MRI, and in 14 (63.6%) out of 22 patients with multiple lesions. MRI with gadolinium-DPTA facilitates identification of the relevant lesion in patients with presumed lacunar infarcts.