There are two types of skin grafts:
-
full thickness skin graft containing
the epidermis and full thickness of dermis
-
split skin graft containing
epidermis and a varibale proportion of dermis.
In oculoplastic surgery, the full thickness graft
is preferred as the resulting graft resist contraction whereas split skin
graft tends to shrink considerably.
The most common sites for autologous skin grafts for oculoplastic
surgery are:
-
upper eyelid skin
-
post or pre-auricular skin
-
supraclavicular skin
The most common causes of skin graft failure:
-
presence of haematoma. This
prevents contact between the graft and the capillary bed of the recipient
and therefore revascularization.
-
infection
-
movement of graft. Capillary
link-up is prevented if the graft is not immobile.
Normal anastomosis of
capillary beds between the
graft and host bed. |
Failure of anastomosis of
capillary bed in area of
haematoma |
Failure of anastomosis due
to graft movement. |
Essential steps in ensuring a successful graft:
-
ensure that bleeding or haematoma is
removed from the recipient bed which may inhibit revascularization
-
all subcutaneous tissue such as fat
is removed from the undersurface of the donor graft which
may interfere with revascularization.
-
use pressure to prevent formation of
haematoma or movement of the graft. This can be done either by applying
a patch directly over the graft (this usually involve covering the whole
eye) for about 5 to 7 days or using precise pressure over the graft such
as the bolus method or tying a cotton roll over the graft.
|