Synonyms

CADASIL; Multi-infarct dementia; Subcortical leukoencephalopathy; Subcortical vascular dementia

Definition

Binswanger’s disease (BD) is a type of subcortical vascular dementia caused by widespread, microscopic damage to cerebral white matter. The damage is usually the result of atherosclerosis (i.e., narrowing of arterial blood vessels) that reduces the supply of blood to subcortical areas of the brain, causing tissue to die. The characteristic pattern of BD-damaged brain tissue can be seen using brain imaging techniques such as computed tomography (CT) or magnetic resonance imaging (MRI). CT imaging of BD often reveals symmetric, noncontrasting hypodensities also called “leukoaraiosis,” and more sensitive MRI imaging reveals diffuse white matter lesions and scattered multiple lacunes (Akiguchi et al. 2014).

There is some controversy in the literature about whether BD constitutes a distinct clinical entity or simply describes the result of different neuropathologies that affect subcortical white matter (Akiguchi et al. 2014; Caplan 1995; Hachinski et al. 2006; Olsen and Clasen 1998; Pantoni and Garcia 1995; Rosenberg et al. 2015). Although the precise cause of BD is unclear, it is frequently associated with diabetes, cardiovascular disease, previous cerebrovascular accident, malnutrition, and, most notably, hypertension. The age of onset for BD is typically between ages 60 and 79 years, with men and women equally affected. Estimates about the incidence of BD range from 3% to 12% (Babikian and Ropper 1987).

Current Knowledge

Neuropathology

Gross pathology of brain tissue affected by BD is characterized by gyral atrophy and widening of the sulci resulting from the loss of cerebral white matter. Lateral ventricles are also typically enlarged. Lacunar infarctions can be found in the white matter, pons, and basal ganglia as well as occasionally in the cerebellum. Microscopic pathology of BD is marked by diffuse and patchy white matter demyelination with areas of reactive gliosis and decreased nerve fibers. The small arteries of the white matter also show fibrous thickening, which is associated with hypertension and cardiovascular disease. There is growing evidence that white matter pathology in BD is related to endothelial dysfunction and neuroinflammation (Huisa and Rosenberg 2014).

Clinical Symptoms

BD typically has a slow, insidious onset that eventually manifests in cognitive and motor dysfunctions related to the disruption of subcortical neural circuits. Specifically, patients exhibit executive dysfunction (e.g., impaired initiation, inhibition, monitoring of goal-directed behavior, and verbal fluency), psychomotor slowing, inattention, and short-term memory loss with poor retrieval but intact recognition (Roman 2003). Other symptoms include changes in speech, an unsteady gait, postural instability, changes in personality or mood (including apathy, irritability, and depression), as well as urinary incontinence (Babikian and Ropper 1987; Caplan 1995; Lezak et al. 2004; Roman 2003).

Treatment

Treatment of BD is often targeted at specific symptoms. For example, medications such as donepezil and memantine may be used to treat the cognitive symptoms associated with BD. Individuals with depression may be treated with antidepressant medications (e.g., selective serotonin reuptake inhibitors (SSRIs) such as sertraline or citalopram) and individuals with agitation or disruptive behavior can be treated with atypical antipsychotic medications such as risperidone or olanzapine (Sink et al. 2005). Antiplatelet therapy and statins have also been recommended for stroke prevention in BD (Huisa and Rosenberg 2014). Other treatment interventions are often focused on reducing cardiovascular risk factors by eating a healthy diet, exercising, and not smoking or drinking too much alcohol. Controlling vascular risk factors can help improve cognition and may even help prevent the development of dementia (Roman 2005).

Prognosis

BD is a progressive disease and there is currently no cure. The course of BD can be variable and deterioration can occur suddenly or gradually and then progress in a stepwise manner (Santamaria Ortiz and Knight 1994).

Cross-References