Cryosurgery Flashcards
necrosis from cell injury occurs from the periphery of the area of freezing
F, centre
tissue cells more resistant to destruction than cancer cells
F, other way around
at periphery, some cells die whilst others remain alive. These have sustained sufficient injury to trigger apoptosis
T
slow freeze with rapid thaw is the ideal formula for cell destruction
F, rapid freeze with slow thaw
conductivity of the material interposed between lesion and cryogen will determine the final freezing temperature and the speed of attaining it
T
air is a better conducting than ice
F, air
2017 T/F - cones or plastic plates contain the sprayed liquid nitrogen within a defined area – semi open technique
T
semi open technique is ideal for dome shaped lesions eg. warts, molluscum and small pyogenic granuloma
T
closed technique uses probes to deliver liquid nitrogen from the unit via a conduit line
T, this maintains the LN in a closed system
if probe from closed technique adheres to surface, abundant warm water facilitates detachment
T
Closed technique as undesirable for vascular lesions
F, ideal for vascular lesions
Semi-closed or chamber technique is not as potent as probe technique
F, as potent or more potent
chamber technique reserved for benign lesions
F - limit to malignancies such as SCC and for palliative cryosurgery
cryosurgery can be applied safely to patients with underlying medical conditions
T
pain is more intense during freezing than thawing stage
F, other way around
better to under treat with repeat treatment for benign lesions
T
COTTON SWABS ARE HELPFUL IN CRYOSURGERY
F, SHOULD BE AVOIDED –> POOR THERMAL CAPACITY
irregular surfaces are better treated with a spray
T
probe better for irregular surfaces
F, use on flat or smooth surfaces
presence of blood does not change temperature
F, incr local temperature
cartilage and bone are very sensitive to freezing
F, very resistant
LN2 poorly tolerated in genital and perianal areas
F, well tolerated
open, semi open and closed techniques are used to treat molluscum contagiosum
T
pigmented lesions very sensitive to freezing
T
darker skin can hyper pigment even with superficial cryosurgery
T
melasma can be treated with cryosurgery
F - p/157 states do not treat melasma with cryosurgery as there is a tendency for residual hyperpigmentaiton
cryosurgery can be helpful for acne lesions
T
cryosurgery can be helpful for scars
T
cryosurgery can be helpful for rhinophyma
T
LN2 should not be used for deep haemangiomas
T
For Kaposi sarcoma, single freeze thaw cycle employed
F, DTFC
only Moh’s has shown better results than cryosurgery for lentigo malignant
T
oedema is more obvious in the face but can be overlooked in other parts of the body
T
eschar formation is unexpected
F , expected p.164
