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Advanced Neurology Covert cerebral small vessel disease

with vascular risk factors have shown that covert vascular Association (AHA) and American Stroke Association
brain injury represents a significant public health concern, (ASA) highlighted topics aimed at improving stroke care
often detectable years before overt clinical manifestations. and fostering collaboration. One focus was the current
Furthermore, the routine use of advanced brain imaging state of clinical care for patients with covert CSVD,
techniques for other medical conditions often reveals encompassing screening, prevention, and management. 5
unforeseen brain lesions indicative of small vessel disease AHA, ASA, and other organizations have defined clinical
in otherwise asymptomatic individuals. Generally, these targets for primary and secondary prevention in their
findings are considered incidental, leading to a lack of practice guidelines. However, consensus on the specific
intervention, particularly among physicians who are not management of incidental or covert CSVD has only been
specialized in neurology. 1 explored recently.
Current evidence indicates that MRI markers of covert The controversies surrounding this topic stem from
CSVD are predictive of future neurological manifestations, the scarcity of high-quality evidence to support specific
including an increased risk of stroke, gait and language recommendations. Key areas of uncertainty include
impairments, cognitive decline, and dementia. CSVD is the effectiveness of brain neuroimaging screening and
considered a significant contributor to vascular dementia alternative non-imaging biomarkers for covert CSVD,
and the severity of Alzheimer’s disease. In addition, it can specific targets for managing risk factors, and their precise
exacerbate post-stroke depression due to the presence of contribution to cerebral small vessel involvement. In
subcortical white matter lesions and is linked to vascular addition, there is limited evidence on the proven efficacy
parkinsonism and tremors, which are associated with of defined treatments on CSVD progression and long-term
lesions in the basal ganglia and thalamus, respectively. vascular outcomes.
Considering the projected rise in the prevalence of stroke
and dementia due to the growing elderly population 2. The spectrum of CSVD. Covert CSVD
worldwide, early detection of CSVD presents a vital CSVD is one of the most common vascular diseases of
opportunity for implementing more effective preventive the brain, occurring more frequently than clinical stroke.
strategies. 2 It encompasses neuroimaging and neuropathological
Despite the identification of CSVD before the onset of findings resulting from prolonged and subtle effects of
clinical symptoms, effective management of this condition vascular risk factors on smaller vessels in the gray and white
remains poorly established and presents a controversial matter, including arterioles, capillaries, and venules. CSVD
challenge for neurologists. Currently, brain MRI biomarkers comprises several subtypes, with the most commonly known
are considered the gold standard for diagnosing covert being deep perforating arteriopathy (or arteriolosclerosis,
CSVD; however, this poses a significant problem due to such as hypertensive) and cerebral amyloid angiopathy.
the high cost and limited availability of MRI technology Although these two conditions are often considered
for community screening in primary care settings. This separate entities, they share notable similarities and likely
challenge is particularly acute in low- and middle-income interact through common mechanisms involving blood-
countries, where recent studies have revealed a high brain barrier (BBB) breakdown, endothelial damage,
prevalence of CSVD. To effectively identify individuals glymphatic system dysfunction, inflammation, and
3
1,2
who may require further evaluation through MRI, there impaired perivascular drainage of β-amyloid.
is a pressing need for less expensive and more accessible CSVD is diagnosed based on brain MRI biomarkers,
screening methods for populations at higher risk. Over the including white matter hyperintensities (WMH) of
past decade, this issue has received increased attention, presumed vascular origin, lacunes, cerebral microbleeds,
leading to the exploration of several alternative biomarkers, enlarged perivascular spaces, cortical superficial siderosis,
such as ambulatory blood pressure monitoring, blood recent small subcortical infarcts, and cerebral microinfarcts.
based-biomarkers, quantitative retinal microvascular This syndrome presents a wide clinical spectrum, with most
assessment, quantitative electroencephalography, carotid cases being asymptomatic or exhibiting under-recognized
ultrasonography, and neurocognitive studies. However, manifestations in the early stages, such as subtle mood
none of these alternatives have matched the diagnostic or behavioral disturbances, gait and balance impairment,
accuracy of brain MRI or been widely adopted in clinical and general functional decline – symptoms frequently
practice for various reasons. 4 attributed to aging. In advanced stages, more pronounced
Awareness of the need for effective management of neurological symptoms emerge. 2,6
covert CSVD has increased recently. At the International Covert CSVD has been detected on neuroimaging in
Stroke Conference in February 2023, the American Heart individuals without neurological symptoms and is highly

Volume 4 Issue 4 (2025) 49 doi: 10.36922/an.4841