Benign nodules and cysts

Question 1

What is a chalazion?

Answer 1

A Meibomian cyst

Question 2

What is the pathogenesis of a chalazion?

Answer 2

Chronic, sterile, granulomatous inflammatory lesion caused by retained sebum secretions from leaking from the meibomian or other adjacent sebaceous glands into the stroma

Question 3

What is it called when a chalazion becomes secondarily infected?

Answer 3

Internal hordeolum

Question 4

What is the histology of a chalazion?

Answer 4

Lipogranulomatous inflammatory reaction with epithelioid histiocytes, multinucleated gianet cells and plasma cells

Question 5

Describe the presentation of a chalazion

Answer 5

Any age
Gradually enlarging painless nodule
Very occasionally if large upper lid chalazion can press on the cornea and induce astigmatism and blurred vision

Question 6

What are the signs of a chalazion

Answer 6

Nodule within the tarsal plate, may be tender if inflamed

On eversion may be associated with a polypoidal granuloma if it has ruptured through the tarsal conjunctiva

Question 7

Who is at increased risk of a chalazion

Answer 7

MGD, Rosacea -> more likely to be recurrent

Question 8

What is a marginal chalazion

Answer 8

Involves a gland of zeiss so it is not located in the tarsal plate it is located in the anterior lid margin

Question 9

What is the treatment of a chalazion

Answer 9

1/3 don’t need treatment as will spontaneously resolve and internal hordeolum may discharge and disappear

1. Surgery - incision and cutterage, lid everted with a special clamp, incision done vertically and contents curretted
2. Steroid injection - preferable if near to the lacrimal punctum because of the risk of surgical damage. Use 0.2 - 2ml of triamcinolone diacetate aqueous suspension diluted with lidocaine to a concentration of 5mg/ml. Inject through the conjunctiva into the tissue around the lesion with a 30 gauge needle

Success rate of steroid injection is 80% and in unresponsive cases lesions can be reinjected 2 weeks later. Subsequent skin depigmentation is uncommon

3. Systemic tetracycline - may be required in recurrent cases particularly if associated with acne rosacea

Question 10

What should you include in your differential for a recurrent chalazion?

Answer 10

Sebaceous gland carcinoma - if any suspicion biopsy it

Question 11

What is an epidermal inclusion cyst

Answer 11

Usually caused by implantation of the epidermis into the dermis secondary to trauma or surgery. It is slow growing, firm, round, superficial or subcutaneous lesion filled with keratin

Question 12

What is an epidermoid

Answer 12

Uncommon and usually developmental, occurs along the embryonic lines of closure. Similar in appearance to an epidermal inclusion cyst

Question 13

What is a dermoid cyst

Answer 13

It is usually subcutaneous or deeper, and attached to the periosteum at the lateral end of the brow. It is caused by skin sequestered during embryonic development

Question 14

What is a sebaceous or pilar cyst

Answer 14

It is caused by a blocked pilosebaceous follicle and contains sebaceous secretions. It is only rarely found on the eyelid although it may occasionally occur at the inner canthus

Question 15

What is a cyst of zeis

Answer 15

Small, non translucent cyst along the anterior lid margin arising from a blocked sebaceous gland associated with an eyelash follicle

Question 16

What is a cyst of moll

Answer 16

Small retention cyst of the lid margin apocrine glands. Round, non tender, translucent fluid filled cyst on the anterior lid margin which might have a slight bluish tinge.

Question 17

What is another name for a cyst of moll

Answer 17

Apocrine hidrocystoma

Question 18

What is an eccrine hidrocystoma

Answer 18

Less common than cyst of moll
Similar in appearance
Usually on medial or lateral aspects of the lid, close to but not involving the lid margin

Question 19

What are millia

Answer 19

Caused by the occlusion of pilosebaceous units leading to the retention of keratin. They represent tiny epidermal cysts. They are tiny, white round superficial papules that tend to occur in crops

Question 20

What are comedones

Answer 20

Retained sebum and keratin in the dilated orifice of hair follicles that often occur in patients with acne vulgaris. They can be open (blackheads) containing darker oxidised material or closed (whiteheads)