Definition :

• A chalazion is a chronic inflammatory granuloma of a meibomian gland. It appears to be caused by alterations in secretions with retention of secretory material due to obstruction of the ducts.
• Chalazia originating in the Zeis sebaceous glands are termed "external chalazia"; those in the meibomian glands of the tarsus are termed "internal chalazia."

Associated Conditions

• seborrhea
• chronic blepharitis
• acne rosacea.

Presentation

• soft tissue swelling
• erythema
• firm nodule
• an acutely inflamed, tender nodule causing significant adjacent tissue reaction.

Course

• As the gland fills with oily secretions, it increases in size over weeks.
• The lesion most commonly is seen to bulge externally through the skin and less commonly through the conjunctiva.
• It may remain contained within the tarsus or break through anteriorly beneath the skin or on the conjunctival side, inducing pyogenic granuloma formation.

Treatment

• medical treatment consists of warm compresses and topical antibiotic ointment.
• When the chalazion does not respond to more conservative medical management after 2 weeks, or when the lesion is large and symptomatic, surgical excision is indicated.
  
• Once excised, continued treatement with warm compresses is generally helpful
• Once excised, treatment with an antibiotic-steroid ointment such as Tobradex also helps resolution of the chalazion

Warnings

• It should be emphasized that any atypical or recurrent chalazion must be regarded as a possible neoplastic lesion and should be biopsied.
• Basal cell carcinoma , squamous cell carcinoma , and adenocarcinoma of the meibomian glands all have been mistaken for chalazia; these are  Malignant ( Malignancy is the tendency of a cancer or tumor either to invade the surrounding tissues, to destroy or replace the tissues previously present or to metastasize (spread to other parts of the body) tumors.