Ectopic Cervical Thymus in an Infant with Normal Orthotopic Thymus: Role of Imaging in Diagnosis and Management

Ectopic cervical thymus (ECT) is a rare cause of solid cervical mass in the pediatric age group. The location of the mass along the path of thymic descent (thymopharyngeal duct), sonographic echo pattern and MR signal intensity identical to that of normal orthotopic thymus in the anterior mediastinum help us in making a confident diagnosis. To the best of our knowledge only nine cases have been reported in infants in the literature. We present a case of ECT presenting as a right upper neck mass in a 2 month old child.