Objective: To verify the incidence of atherosclerotic obstructions and microscopic atherosclerotic lesions in radial arteries dissected from cadavers of over 34-year-olds. Methods: Twenty-nine cadavers had both radial arteries dissected as if they were going to be utilized as coronary artery bypass grafts. An angiogram was performed to determine atherosclerotic obstructions of the radial arteries. Subsequently, 3 fragments of each artery (proximal, medial, distal) were prepared on microscope slides using hematoxylin-eosin in order to identify microscopic atherosclerotic lesions. Results were compared with risk factors found in the patient's records: age, gender, hypertension, diabetes, history of smoking, myocardial infarction, stroke, peripheral vascular disease, obesity, family history. Results: No obstructive lesions were found in the angiograms. Four cadavers presented with microscopic atherosclerotic and pre-atherosclerotic lesions. Among the risk factors considered, only age was correlated with microscopic lesions. The arteries measured, on average, 19.22 cm in males and 17.45 cm in females. Their diameters were 1.87 mm for men and 1.72 mm for women. Conclusions: No atherosclerotic obstructions were found in the radial arteries of these cadavers. 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