Lacunar stroke

The modern period in the history of stroke began in the 1960s when C. Miller Fisher described detailed clinical and pathological observations on the features of lacunar strokes, carotid artery disease, transient ischemic attacks, and intracerebral hemorrhage. His student Louis Caplan established one of the first stroke registry... 

The reasons for the observed differences in mortality between aspirin-treated patients in 1ST and CAST are unclear. The findings may relate to baseline differences between the treated groups. CAST had a younger age profile (72% under 70 compared to 38% in 1ST), excluded some patients with severe stroke, and likely included more subjects with lacunar stroke, an etiology associated with lower mortality and less disability. 

Lacunar stroke is characterized by occlusion of a small penetrating artery creating a small deep infarct. Lacunar strokes have the lowest early recurrence risk and best survival rates, but may still cause significant functional morbidity. Although subgroup analyses are available from secondary prevention trials in lacunar stroke, few clinical trial data are available regarding nonthrombolytic antithrombotic therapy for lacunar stroke in the acute setting. 

Cardioembolic strokes may also have poor outcome, especially with large emboli as in AF. In the Rochester population, patients with cardioembolic stroke were the most impaired during the hospitalization only 14% were independent as compared to 38% with lacunar stroke, 24% with atherosclerotic stroke, and 27% with ischemic stroke of unknown cause. " The latter group probably included patients with emboli of unknown origin. As evidence of the proportion of patients with devastating strokes, patients classified as cardioembolic subtype were also least likely to be independent at 1 year (27%). 

Small vessel/lacunar strokes have better short- and long-term (1-year) survival as compared to other stroke subtypes. In the NINDS trial of rt-PA within 3 hours of onset, patients classified as small vessel stroke on the basis of their clinical syndrome had a 50% chance of a normal NIHSS score at 3 months if they received placebo, increasing to 70% in the treatment group. In the Lausanne cohort, 95% were independent after their first event, as opposed to only 65% of the cardioembolic strokes and 49% with large vessel atherothrombotic infarctions. Eighty-two percent of patients with small vessel stroke were independent at 1 year. Even at the time of maximal deficit, between 38% and 64% of small vessel/lacunar patients were independent, with motor impairment and extent of white matter disease adversely affecting outcomes. " In TOAST, small vessel/lacunar stroke was the only subtype associated with a favorable outcome, independent of the NIHSS score. ... 

It may be especially difficult to confidently establish the diagnosis of the most benign subtype of stroke, small vessel/lacunar stroke, accounting for 10-29% of all... 

Salgado AV, Eerro J M, Gouveia-Oliveira A. Long-term prognosis of first-ever lacunar strokes a hospital-based study. Stroke 1996 27(4) 661-666. 

Toni D, Del Duca R, FiorelU M, Sacchetti ML, Bastianello S, Giubilei F, Martinazzo C, Argentino C. Pure motor hemiparesis and sensorimotor stroke accuracy of very early clinical diagnosis of lacunar strokes. Stroke 1994 25(l) 92-96. 

Amarenco P, Hauw JJ (1990) Cerebellar infarction in the territory of the anterior and inferior cerebellar artery. A clinico-pathological study of 20 cases. Brain 113 139-155 Baquis GD, Pessin MS, Scott RM (1985) Limb shaking - a carotid TIA. Stroke 16 444-448 Barth A, Bogousslavsky J, Regli F (1994) Infarcts in the territory of the lateral branch of the posterior inferior cerebellar artery. J Neurol Neurosurg Psychiatry 57 1073-1076 Baumgartner RW, Sidler C, Mosso M et al (2003) Ischemic lacunar stroke in patients with and without potential mechanism other than small-artery disease. Stroke 34 653-659... 

Fisher CM (1965c) The vascular lesion in lacunae. Trans Am Neurol Assoc 90 243-5 243-245 Fisher CM (1967) A lacunar stroke. The dysarthria-clumsy hand syndrome. Neurology 17 614-617 Fisher CM (1977) Bilateral occlusion of basilar arterybranches. 

Diffusion tensor imaging (DTI) is a sophisticated form of diffusion imaging that is not yet routinely used in clinical stroke. However, it is becoming increasingly popular as a research tool (Sotak 2002), particularly in small lacunar stroke (Gillard et al. 2001 Lie et al. 2004) and in patients with ischemic leukoaraiosis (O Sullivan et al. 2001, 2004), and will, thus, be shortly described here. 

DWI promises to have tremendous value in accurately localizing the subcortical or brainstem lesion(s). A summary of studies of DWI in patients with lacunar stroke is provided in Table 13.2. It is noteworthy that there is also a group of patients with lacunar infarction who harbor multiple chronic white matter lesions on the conventional MRI and present with non-specific syndromes that could not be attributed to a specific arterial territory. Such symptoms include worsening of a preexisting dysarthria, dysphagia or ataxia, sudden appearance of emotional incontinence or recent onset bowel or bladder problems. Excellent diagnostic performance of DWI in lacunar infarctions may help to prove ischemia as the cause of non-specific neurological symptoms in such patients. 

Table 13.2. Studies of DWI in patients with lacunar stroke. [Reprinted with permission from Gass et al. (2004)]...

Fisher CM (1982) Lacunar strokes and infarcts a review. Neurology 32 871-876... 

Jackson C, Sudlow C (2005). Are lacunar strokes really different A systematic review of differences in risk factor profiles between lacunar and non-lacunar infarcts. Stroke 36 891-901... 

Boiten J, Rothwell PM, Slattery J et al. (1996). Ischemic lacunar stroke in the European Carotid Surgery Trial. Risk factors, distribution of carotid stenosis, effect of surgery and type of recurrent stroke. Cerebrovascular Diseases 6 281-287 Boon A, Lodder J, Cheriex E et al. (1996). 

Tegeler GH, Shi F, Morgan T (1991). Carotid stenosis in lacunar stroke. Stroke 22 1124-1128 Tietjen GE (2005). The risk of stroke in patients with migraine and implications for migraine management. CNS Drugs 19 683-692 Turan TN, Stern BJ (2004). Stroke in pregnancy. 

It may be difficult to distinguish between some partial anterior circulation syndromes and a lacunar stroke. 

Mead GE, Lewis SC, Wardlaw JM et al. (1999). Should CT appearance of lacunar stroke influence patient management Journal of Neurology, Neurosurgery and Psychiatry 67 682-684... 

Partial or generalized epileptic seizures occur for the first time in about 2% of those with acute strokes at around the time of onset, rising to approximately 10% at five years, more with large cortical infarcts or intracranial hemorrhage (Ch. 9) (Ferro and Pinto 2004). Seizures are more common with large strokes, especially if hemorrhagic, and with cortical as opposed to lacunar strokes. Cerebrovascular disease is the most common cause of epilepsy in the elderly, and late-onset epilepsy is a predictor of subsequent stroke (Cleary et al. 2004). Seizures may cause neurological deterioration or be mistaken for recurrent stroke. Intractable recurrent seizures are distinctly unusual. 

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