Duplex Sonographic Protocol for establishment of reference luminal diameters and intima-media thickness of Carotid Arteries in a West African Population
Keywords:
Duplex scan protocol, Carotid artery, Luminal diameter, Intima-media thickness, West African populationAbstract
Duplex sonography is the primary imaging modality for carotid artery disease, but its accuracy depends on a standardized protocol and population-specific reference values, which are lacking for West Africa. We describe a detailed sonographic protocol applied to a cohort of 104 healthy Nigerian adults. Using a 7.0 MHz linear transducer, the luminal diameters of the common, internal, and external carotid arteries were measured in end-diastole, 1 cm from the bifurcation. The study presents a step-by-step imaging protocol that is feasible in a resource-limited setting. The resulting reference ranges for carotid luminal diameters are: Common Carotid Artery: 0.45-0.76 cm, Internal Carotid Artery: 0.44-0.75 cm, and External Carotid Artery: 0.30-0.67 cm. These values were consistent across sexes and sides. We provide a standardized, reproducible duplex sonography protocol and the first set of normative reference values for carotid luminal diameters in a West African population. This resource will aid sonographers and clinicians in improving the accuracy and reliability of carotid ultrasound examinations in the region.
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