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The lacunar state arises from repeated lacunar infarctions, these culmunative minor strokes give rise to a form of a gradually increasing dementia. Physical signs of difficulties with gait, speech and swallowing precede obvious mental deterioration. The strokes are more common in people with hypertension.
Signs & Symptoms Edit
Each of the 5 classical lacunar syndromes has a relatively distinct symptom complex. Symptoms may occur suddenly, progressively, or in a fluctuating (e.g., the capsular warning syndrome) manner. Occasionally, cortical infarcts and intracranial hemorrhages can mimic lacunar infarcts, but true cortical infarct signs (such as aphasia, neglect, and visual field defects) are always absent. The 5 classic syndromes are as follows:
|Name||Location of infarct||Presentation|
|Pure motor stroke/hemiparesis (most common lacunar syndrome: 33-50%)||posterior limb of the internal capsule, basis pontis, corona radiata||It is marked by hemiparesis or hemiplegia that typically affects the face, arm, or leg of one side. Dysarthria, dysphagia, and transient sensory symptoms may also be present.|
|Ataxic hemiparesis (second most frequent lacunar syndrome)||posterior limb of the internal capsule, basis pontis, and corona radiata, red nucleus, lentiform nucleus, SCA infarcts, ACA infarcts||It displays a combination of cerebellar and motor symptoms, including weakness and clumsiness, on the contralateral side of the body. It usually affects the leg more than it does the arm; hence, it is known also as homolateral ataxia and crural paresis. The onset of symptoms is often over hours or days.|
|Dysarthria/clumsy hand (sometimes considered a variant of ataxic hemiparesis, but usually still is classified as a separate lacunar syndrome)||basis pontis, anterior limb or genu of internal capsule, corona radiata, basal ganglia, thalamus, cerebral peduncle||The main symptoms are dysarthria and clumsiness (i.e., weakness) of the hand, which often are most prominent when the patient is writing.|
|Pure sensory stroke||contralateral thalamus (VPL), internal capsule, corona radiata, midbrain||Marked by persistent or transient numbness, tingling, pain, burning, or another unpleasant sensation on one side of the body.|
|Mixed sensorimotor stroke||thalamus and adjacent posterior internal capsule, lateral pons||This lacunar syndrome involves hemiparesis or hemiplegia with ipsilateral sensory impairment|
Silent lacunar infarctionEdit
A Silent lacunar infarction (SLI) is one type of silent stroke which usually shows no identifiable outward symptoms thus the term "silent". Individuals who suffer a SLI are often completely unaware they have suffered a stroke. This type of stroke often causes lesions in the surrounding brain tissue that are visibly detected via neuroimaging techniques such as MRI and computerized axial tomography (CT scan). Silent strokes, including silent lacunar infarctions, have been shown to be much more common than previously thought, with an estimated prevalence rate of eleven million per year in the United States. Approximately 10% of these silent strokes are silent lacunar infarctions. While dubbed "silent" due to the immediate lack of classic stroke symptoms, SLIs can cause damage to the surrounding brain tissue (lesions) and can affect various aspects of a persons mood, personality, and cognitive functioning. A SLI or any type of silent stroke places an individual at greater risk for future major stroke.
- ↑ Beaumant J.G., Kenealy, P.M. & Rogers, M.J.C. (1999). The Blackwell Dictionary of Neuropsychology. Oxford:Blackwell
- ↑ Grau-Olivares M,et al. Neuropsychological abnormalities associated with lacunar infarction. J Neurol Sci. 2007 Jun 15;257(1-2):160-5. Epub 2007 Feb 20. PMID 17316693
- ↑ Longstreth WT Jr, et al. Lacunar infarcts defined by magnetic resonance imaging of 3660 elderly people: the Cardiovascular Health Study. Arch Neurol. 1998 Sep;55(9):1217-25. PMID 9740116