FAVA is most often diagnosed in older children, teens and young adults, though it has been diagnosed earlier and later in a patient's life. The constellation of clinical, radiologic, and histopathologic findings typically allow the diagnosis of FAVA. The most helpful imaging studies are ultrasonography (US) and magnetic resonance imaging (MRI). The major imaging features of FAVA include the presence of complex intramuscular solid lesion replacing normal muscle fibers with<unk> fatty overgrowth and phlebectasia. The extrafascial part is composed of fatty overgrowth, phlebectasia, and occasional lymphatic malformation. The histopathologic findings in FAVA include dense<unk> us tissue, fat, and lymphoplasmacytic aggregates within atrophied skeletal muscle.<unk>  tissue within skeletal muscles are associated with large, irregular, and sometimes excessively muscularized venous channels and smaller, clustered channels. Organizing thrombi, lymphatic foci and enlarged nerves encircled by dense<unk> us tissue are also frequently noted in FAVA.
Fibro-adipose vascular anomaly
Connective tissue neoplasm
Gonadal tissue neoplasm
Iatrogenesis
Endocrine gland neoplasm
Vascular ring
Surgical stress
Vascular anomaly