Tarsal (meibomian) glands

Looks like

About 30 long oil glands standing in a row inside the tarsal plate of each upper lid, fewer in the lower, opening just behind the lashes.

What it does

Pour an oil layer onto the tear film at every blink, which stops tears from evaporating and spilling over the lid edge.

Keeping it well

Blocked glands are the commonest cause of dry, gritty eyes (meibomian gland dysfunction) and of a chalazion. Warm compresses and lid cleaning are the first treatment; a chalazion that keeps coming back in an older adult should be biopsied.

Related conditions

• Blepharitis & styes
• Cataract
• Conjunctivitis
• Corneal abrasion (scratched eye)
• Dermatomyositis and polymyositis
• Drooping eyelid (ptosis)
• Dry eye disease
• Hyperthyroidism & Graves' disease
• Keratitis (corneal infection and ulcer)
• Keratoconus
• Presbyopia
• Retinal detachment
• Retinoblastoma
• Sjögren's disease
• Squint & lazy eye
• Trachoma
• Trichinellosis
• Uveitis & iritis