A cross-sectional feasibility study of neurovascular ultrasound in Malawian adults with acute stroke-like syndrome

Background

In sub-Saharan Africa, there is a dearth of epidemiologic data on the burden of cerebral ath-erosclerosis. This is explained by the limited availability and the high cost of standard vascu-

lar imaging techniques. Neurovascular ultrasound is portable, cheaper and non-invasive and could, therefore, represent a reasonable alternative to fill this knowledge gap. We explored the feasibility of neurovascular ultrasound in Malawian adults with acute stroke-like syndrome to inform the design of future large stroke studies comparing its diagnostic perfor-

mance to that of gold standard vascular imaging techniques in sub-Saharan Africa.

Methods

We enrolled consecutive patients diagnosed with acute stroke-like syndrome based on the World Health Organization definition. Clinical and demographic data were recorded, and a comprehensive neurovascular ultrasound was performed. Fisher’s exact and Kruskal-Wallis

tests were used to study the relationship between atherosclerosis and potential risk factors.

Results

Sixty-six patients were enrolled (mean age: 58.7 years). The frequency of extracranial ath-erosclerosis was 39.4% (n = 26, 95% CI: 28.6–52.2). There were 12 patients with abnormal carotid intima media thickness (18.2%, 95% CI: 9.8–29.6) and 14 patients with a carotid pla-que (21.2%, 95% CI: 12.1–33.0). The frequency of intracranial atherosclerosis was 19.2%(95%CI: 6.6–39.4) in 26 patients with successful transcranial insonation. Hypertension(80.8 versus 52.5%, p = 0.03) and hypercholesterolemia (11.5 versus 0.0%, p = 0.05) were more prevalent in patients with extracranial atherosclerosis.

Conclusions

This study demonstrates the feasibility of neurovascular ultrasound to assess cervical arter-ies in adults with stroke-like syndrome in sub-Saharan Africa. There is a high rate of tran-scranial insonation failure in this setting, highlighting the need for echocontrast agents.