Chalazion Flashcards
What is a chalazion also known as?
Meibomian cyst
What is a chalazion?
A focus of granulomatous inflammation in the eyelid arising from a blocked meibomian gland
What is a meibomian gland also known as?
Tarsal gland
What are meibomian glands?
Modified sebaceous gland located in the tarsal plates of the upper and lower lids
What are the tarsal plates?
Two relatively tough elongated pieces of fibrous connective tissue which forms the infrastructure of the eyelid
How many meibomian glands are there in each lid?
20-25
What is the function of the meibomian glands?
To secrete meibum, the lipid component of the tear film
What causes a chalazion?
Non-infectious drainage occlusion of the gland causing extravasation of meibum into the eyelid soft tissues
What follows meibum outflow obstruction and extravasation in chalazion?
Focal secondary inflammatory reaction
What are the risk factors for chalazion?
- Chronic blephritis
- Rosacea
- Seborrhoeic dermatitis
- Pregnancy
- DM
How does a chalazion typically present?
Gradually enlarging, roundish, firm lesion in either the upper or lower lid
Which lid is more commonly affected by chalazion?
Upper
How big is a chalazion typically?
2-8mm in diameter
Are chalazion painful?
No, but can be a little tender to start
What is seen on evertion of the eyelid in chalazion?
A discrete, immobile, round, yellowish lump
What should NOT be seen in chalazion?
- Ulceration
- Bleeding
- Telangiectasia
- Tenderness
- Discharge
How doe chalazion typically resolve?
Drain through the inner surface of the eyelid and absorb spontaneously over 2-8 weeks
How are chalazion diagnosed?
Clinically
When may a chalazion require histological investigation?
In recurrent or atypical presentations
How can a chalazion be differentiated from a stye?
- Overlying skin is more mobile
- Chalazion is small, non-tender and central VS stye is painful and localises to the margins
- Chalazion is a yellow swelling visible on evertion VS stye is small pustule at base of eyelash
What are the differentials for chalazion?
- Internal or external stye
- Orbital or preseptal cellulitis
- Early herpes zoster
- Herpes simplex
- Tumour
What tumours may present like a chalazion?
- Sebaceous gland carcinoma
- Skin cancer
How can spontaneous resolution of chalazion be improved?
- Twice daily warm compression
- Massaging lids towards edge
When should further intervention be considered for chalazion?
Progressively enlarging lesions
What further interventions can be used in chalazion?
- Minor operation
- Triamcinolone
What can be a potential complication of chalazion?
Large chalazion can cause astigmatism by pressing on the cornea