Y5 - Epidermoid and pilar cysts (sebaceous cysts) Flashcards
what are the two forms of sebaceous cysts
epidermal cysts
pilar (trichelemmal cysts)
what is a cyst
a closed fluid filled sac
what do epidermal and pilar cysts contain
keratin
do epidermal or pilar cysts originate from the sebaceous glands
neither originate from the sebaceous gland
where do epidermal cysts originate from
epidermis
where do pilar cysts originate from
hair follicles
what are ‘true’ sebaceous cysts contain and what do they develop from
contain sebum
originate from sebaceous cysts
where are common sites for sebaceous cysts
in hairier areas such as scalp, ears, face, back
where will sebaceous cysts not form
hands and soles of feet (no hair)
history of sebaceous cyst
smooth to touch, mobile, variable size, round shape
what do sebaceous cysts contain
kertatin (cottage cheese with a cheesy odour)
what sort of epithelium is associated with a epidermal cyst
squamous epithelium
definition of a epidermal cyst
a benign cyst on the skin
where do epidermal cysts normally develop from
ectodermal tissue (epidermis)
history of epidermal cyst
usually present on area with little hair
may be asymptomatic or may be tender when touched and release pus
aetiology of epidermoid cysts
implantation of epidermis into the dermis due to trauma or surgery
risk factors for epidermoid cysts
gardners syndrome
trigeminal neuralgia
body piercings
investigations of epidermal cysts
definitive diagnosis by pathologist:
-cystic lesion with cornified epithelium containing keratin without calcifications
where do the majority of pilar cysts occur
scalp (areas of hair follicles)
who are pilar cysts common in
women
aetiology of pilar cysts
derived from outer root sheath of hair follicle
history
common to see many cysts in areas of hair which are smooth mobile and filled with keratin
pathophysiology of epidermoid cyst
from the proliferation of epidermal cysts
management of epidermoid cyst
do not need to be treated if asymptomatic
what may clean up the inflammation in epidermoic cysts
an intralesional injection of triamcinolone
surgical management for epidermoid cysts
removal via simple excision or incision with removal of the cyst and cyst wall
triamcinolone may lead to faster resolution of symptoms
complications of epidermoid cyst
if entire cyst is not removed, lesion may recur
infection
management of pilar cyst
definitive treatment is the complete excision of the cyst
- linear excision
- elliptical excision
- punch incision
prognosis of pilar cyst
good, majority are cured with complete surgical removal
