Xanthomatous infiltration of tendons is a clinical feature common to many cases of hyperlipidemia. The xanthomas can be detected and only grossly assessed by palpation. This report describes a radiological technique used to assess these lesions at the Achilles tendon level. The "mammography technique" applied to the study of Achilles tendons was used in 32 normolipemic subjects and 32 hyperlipidemic patients. Both tendons could be observed in their entire length and their thickness, greatly increased in xanthomatosis, could be accurately measured. The results of this survey suggest that the radiological approach may provide a useful tool for the routine evaluation and follow-up of tendon xanthomas.