Case Report: 63 years male with chronic ankle pain , no trauma, known diabetic.MRI showing gross thickening & heterogeneous increased signal in T1/T2/STIR in distal achilles tendon upto calcaneal insertion with focal lobulated lesion in the distal tendon with iso to hyperintense signal with intact surrounding fat planes – not specific to etiology,possibly achilles tendon xanthoma, in view of history. Differentials - chronic tendon degeneration, tophaceous gout,tendonitis/others.
Teaching Points by Dr MGK Murthy & Dr GA Prasad: Xanthomas are nonneoplastic lesions due to local collection of lipid-laden macrophages, giant cells, and other inflammatory cells in response to the deposition of cholesterol in tissue. Xanthomas commonly occur in the skin, especially that of the eyelids . The lesions are less commonly seen in the tendons and synovium. Tendinous xanthomas most often involve the extensor tendons of the hands, the Achilles tendon, and the patellar tendon with well-established association between tendinous xanthomas and primary hyperlipidemia, in particular, type IIa hyperlipidemia and type III hyperlipidemia. On MRI Achilles tendon shows masses with nonspecific higher signal intensity on both T1- and T2-weighted spin-echo images.