Mells anatomy congenital anomalies of thyroid, parathyroid and adrenal

CONGENITAL ANOMALIES

Nur Amalina bt. Aminuddin Baki082012100067

Objectives

• To understand the congenital anomalies that can be present in o Thyroid glandso Parathyroid glandso Adrenal glands

Anomalies of Shape

• Pyrimidal lobe o Arise from isthmus or one of the lobesoMay have no connection with thyroid oMay be divided into two or more parts

• Isthmus may be absent• One of the lobes of gland

oMay be very small or absent

Anomalies of Position

• Lingual thyroido Under mucosa of dorsum of tongue oMay form swelling and difficulties in swallowing

• Intra- lingual thyroido Embedded in muscular substance of tongueo Suprahyoido Lie in midline of neck, above hyoid bone

• Infra- hyoid thyroid o Lie below hyoid bone, but above normal position

• Intra-thoracic thyroid o Entire gland or part of it may lie in the thorax

Ectopic Thyroid Tissue

• Found anywhere along path of descent of thyroid gland

• Commonly found in the base of tongue, just behind foramen caecum

Remnant of Thyroglossal Duct

• May persist and lead to formation of:• Thyroglossal Cyst

o Cystic remnant of thyroglossal ducto At any point along migratory pathway of thyroid

glando Always near or in midline off necko 50% - close or inferior to body of hyoid boneo Some at base of tongueo Some close to thyroid cartilage

• Thyroglossal FistulaoWhen thyroglossal cyst is connected to outside by

fistulous canalo Usually arises secondarily after rupture of a cystoMay be present at birth

• Carcinoma of thyroglossal duct

Adrenal Gland Anomalities• Ectopic adrenal cortical tissue• Ectopic adrenal gland– May lie deep to capsule of kidney– May be fused to liver or kidney

• Hyperplasia of Adrenal GlandoMale( adrenogenital syndrome)

Marked by early development of secondary sexual characters

oFemale( Pseudohermaphroditism)Enlargement of clitoris Child may be mistaken for male

Reference

• Human Embryology, 8th Edition, Inderbir Singh and G P Pal.

• Human Embryology, Langman’s