<unk>  is a condition where thymus tissue is found in an abnormal location. It usually does not cause symptoms, but may leads to a mass in the neck that may compress the trachea and the esophagus. It is thought to be the result of either a failure of descent or a failure of involution of normal thymus tissue. It may be diagnosed with radiology, such as an ultrasound or magnetic resonance imaging. If it causes illness, surgery can be used to remove it. Recurrence after surgery is very unlikely.
Ectopic thymus
Abscess of thymus
Cervical thymic cyst
Tracheal agenesis
Persistent thyroglossal duct
Salivary gland atresia
Ectopic salivary gland tissue
Salivary gland aplasia