According to Illingworth's theory, the inclusion of ectopic parotid epithelium in the upper deep cervical lymph nodes leads to the formation of
Branchial cyst
• It develops from persistence of precervical sinus, a small depression deep to the second arch that normally disappears during development.
• According to Illingworth's theory, inclusion of ectopic parotid epithelium in the upper deep cervical lymph nodes leads to branchial cyst formation.
• Though congenital, it often manifests itself between 20-25 yrs. of age, or even later. Presents as a painless swelling in the upper and lateral part of the neck.
• It shows a tendency of recurrent infection due to presence of lymphoid tissue in its wall. In that case it becomes painful.
• Cholesterol crystals can be demonstrated in the aspirated fluid from a branchial cyst.
Branchial cyst.
Branchial fistula.
Cystic hygroma.
Thyroglossal fistula.