Chalazion (Meibomian cyst)
Chalazion is the chronic inflammation of Meibomian glands due to blockage of its ducts.
Pathologically Chalazion is a chronic lipogranulomatous inflammation. It is not a true cyst as it is not lined by epithelium, rather it is lined by granulation tissue.
Pathology of Chalazion
Blockage of Meibomian duct
Stagnation of the gland content (Sebum)
When limit is crossed, it will burst and gland content will be released into muscle and surrounding structures.
The moment sebum comes out, body immunity system recognizes it as a foreign particle.
It will elicit chronic inflammation
Clinical features of Chalazion:
Painless swelling with:
· Overlying healthy skin (not erythematous)
· Firm in consistency
· Located away from the lid margin
On eversion of lid, yellow granuloma is visible.
Treatment of Chalazion:
1. Spontaneous resolution = very less chance
2. Intra-lesionla steroids = triamcinolone-di-acetate (0.5 to 1.0 ml)
3. Incision and curettage (best option)
A vertical incision through the conjunctival surface is given. Horizontal incision is not given to avoid damage to other Meibomian ducts. Infiltrating anesthesia is given to the submuscular layer (Dexocaine 0.5 – 1 cc)
The incision is given through the conjunctival surface because:
1. Easy approach
2. To avoid scar on lid surface
3. As inflammation is more marked posteriorly
But if it bursts into skin surface, more anterior inflammation is present. Only then a horizontal skin incision is given. The incision here is horizontal because the orbicularis oculi muscle is round, so if vertical incision is given through skin, it will be injured.