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Relay transplantation: A new method of expanding a free skin graft
A NEW METHOD SKIN GRAFT By JGi
SMAHEL,
OF EXPANDING
M.D., and NUOT GANZONI, M.D.
Second Surgical Department, University Hospital, Ziirich, Switzerland EXPANDING a skin graft thereby increasing the area which it can re-epithelialise depends on epithelial outgrowth, the amount of which is directly related to the length of the free margins of the graft. A graft may be expanded by cutting it into smaller pieces placed apart from each other on the defect or rather more elegantly by meshing it (Tanner et al., 1964). The ultimate in expansion techniques is the transplantation of discrete epithelial cells (Billingham and Reynolds, 1952-53) but this is time consuming and the scar which results is poor. Earlier (Smahel, 1972) we reported the possibility of transplanting a graft repeatedly This and thereby successively sowing a wound surface with its outgrown epithelium. epithelium becomes autonomous as regards growth potential after 5 to 7 days and when the transplant is removed at this point, the epithelialisation of the wound proceeds undisturbed. The original investigations with perforated grafts verified the feasibility of relay transplantation but there were technical difficulties and a new, more reliable technique has been developed.
FIG.
FIG . 2.
28
FIG.
I
FIG. I.
Freshly transplanted
The strips 7 days later. I-D
strips on granulation
2
tissue.
The spaces between the individual strips are partially epithelialised. 49
BRITISH JOURNAL
OF PLASTIC
SURGERY
FIG.3 FIG.3. Superficial FIG.4.
F1c.4
incision along the original edge of the strips. On the lower edge of the picture, homograft is being used to prepare the next recipient site.
The strips have been removed from the first recipient
FIG.5. The edge of a peeled-off strip.
site and transferred
H & E.
a
on to the second (left).
x220.
TECHNIQUE
Three to 6 mm wide strips of split skin, with a thickness about one-quarter that of full skin, were used. Histologically the grafts comprised epidermis, stratum _ _ _ papillare and a thin layer of the stratum reticular-e corii. The strips were placed on the recipient bed 5 to IO mm apart (Fig. I). When epithelial growth became clinically obvious, usually between the 5th and 7th day (Fig. 2), a very superficial incision was made along the original margins of the transplants separating them from the expanding epithelial explants (Fig. 3). Bleeding following this incision was minimal. One end of the strip was picked up with a thumb forceps and the entire transplant peeled off the underlying
RELAY
FIG. 6.
On the right,
FIG. 7.
Freshly
FIG. 8.
The area in Figure
FrG. g.
The
SI
the first recipient site 15 days following transplantation Left, the strips after 8 days on the second the strips.
transpIanted
area
TRANSPLANTATION
strips
The on the upper arm. homografts.
7, 5 days later. Left,
seen in Figure
intended
second
On the right, the first recipient the second site grafted.
The strips were 8, 7 days later. various small raw areas.
again
and 8 days after removal site.
of
recipient
by
site is covered
site after removal peeled
of the strips.
off and used
to cover
FIG. IO. The same area as in Figures 7 to 9. On the right, the first recipient site zo days after transplantLeft, the second site 15 days following grafting and 8 days ation and 15 days after removal of the strips. after removal of the strips.
bed. Bleeding thereafter from the granulation tissue was often intense, bur subsided rapidly under pressure. The peeled-off strips were then wiped free from blood and placed on the next recipient site (Fig. 4). Peeling off and retransplantation hardly bother the patient at all. Histological examination of the peeled-off strips demonstrated indirectly that epithelium had been left behind on the granulations (Fig. 5). Within 6 to 8 days the epithelial explants on the first area consolidated and formed a continuous layer. At the same time the strips had taken on their second location (Fig. 6).
52
BRITISH JOURNAL OF PLASTIC SURGERY
FIG. xI. Histological appearance of a strip that was transplanted and peeled off three times. H &E.
x 200.
The amount of expansion possible is shown in Figures 7 to IO. Note, too, the use of homograft skin to prepare the next recipient site; this enhances the success of the take. Experimentally, we have succeeded in transferring strips up to 4 times. Even after the third removal the histological picture was satisfactory. The corium was slightly oedeThe epidermis was hyperplastic. matous and showed mild mononuclear infiltration. The borderline between the stratum basale and the stratum spinosum was unclear and a marked polymorphism of the cells and their nuclei was observed. Some cells showed perinuclear vacuolisation (Fig. I I). The technique has now been used on 5 patients with extensive deep burns. Altogether 37 transplants were employed. DISCUSSION
We have shown that the thinner the graft, the earlier its epithelium will be transferred to the granulations (Ganzoni and Smahel, 1973). But too thin grafts are easily torn when peeled off and the quarter thickness represents the best compromise. Retransplantation of the strips was performed at intervals of 5 to 7 days and exLarger numbers of cells have perience shows that the 7-day interval is preferable.
RELAY TRANSPLANTATION
53
then migrated on to the granulations, their survival is more certain and growth progresses more rapidly. The retransplanted strips must have intimate contact with the underlying bed. If this is not achieved, epithelium may proliferate on the underside of the transplant. The factor limiting the number of possible retransplantations is, in our experience, not exhaustion of the regenerative capacity of the epidermis but the mechanical tearing Further, in some strips the epidermis became of the strips when peeling them off. detached. Shepard (1972) and Ashbell (1972) have written about “The storage of split skin Our technique could be characterised as the storage of grafts on their donor sites”. split grafts on their recipient sites. The advantage of the recipient area being able to profit from its storage of the grafts is obvious. SUMMARY A method of skin transplantation is presented whereby a wound may be successively sown with epithelium by the repeated transfer of the same strips of split thickness skin. REFERENCES ASHBELL,T. S. (1972). Letter to the Editor: The storage of split skin grafts on their donor sites. Plastic and Recomtructive Surgery, 50, 178-179. BILLINGHAM,R. E. and REYNOLDS,J. (1952-53). Transplantation studies on sheets of pure epidermal epithelium and on epidermal cell suspensions. British Joumal of Plastic Surgery, 5, 25-36.
GANZONI, N. and SMAHEL, J. (1973). Zur Wahl der Transplantatdicke bei der freicn Transplantation von Haut. Helvetica chirtrrgica Acta, 40, 267-269. SHEPARD,G. H. (1972). The storage of split-skin grafts on their donor sites. Plasric amI Reconstructive Surgery, 49, I 15-122.
SMAHEL,J. (1972). The “relay” graft. British youwlai of Plastic Surgery, 25, 432-434. TANNER, J. C., VANDEPUT,J. and OLLEY, J. F. (1964). The mesh skin graft. Plastic: arid Recomtructive
Surgery, 34, 287-292.
SMAHEL,
OF EXPANDING
M.D., and NUOT GANZONI, M.D.
Second Surgical Department, University Hospital, Ziirich, Switzerland EXPANDING a skin graft thereby increasing the area which it can re-epithelialise depends on epithelial outgrowth, the amount of which is directly related to the length of the free margins of the graft. A graft may be expanded by cutting it into smaller pieces placed apart from each other on the defect or rather more elegantly by meshing it (Tanner et al., 1964). The ultimate in expansion techniques is the transplantation of discrete epithelial cells (Billingham and Reynolds, 1952-53) but this is time consuming and the scar which results is poor. Earlier (Smahel, 1972) we reported the possibility of transplanting a graft repeatedly This and thereby successively sowing a wound surface with its outgrown epithelium. epithelium becomes autonomous as regards growth potential after 5 to 7 days and when the transplant is removed at this point, the epithelialisation of the wound proceeds undisturbed. The original investigations with perforated grafts verified the feasibility of relay transplantation but there were technical difficulties and a new, more reliable technique has been developed.
FIG.
FIG . 2.
28
FIG.
I
FIG. I.
Freshly transplanted
The strips 7 days later. I-D
strips on granulation
2
tissue.
The spaces between the individual strips are partially epithelialised. 49
BRITISH JOURNAL
OF PLASTIC
SURGERY
FIG.3 FIG.3. Superficial FIG.4.
F1c.4
incision along the original edge of the strips. On the lower edge of the picture, homograft is being used to prepare the next recipient site.
The strips have been removed from the first recipient
FIG.5. The edge of a peeled-off strip.
site and transferred
H & E.
a
on to the second (left).
x220.
TECHNIQUE
Three to 6 mm wide strips of split skin, with a thickness about one-quarter that of full skin, were used. Histologically the grafts comprised epidermis, stratum _ _ _ papillare and a thin layer of the stratum reticular-e corii. The strips were placed on the recipient bed 5 to IO mm apart (Fig. I). When epithelial growth became clinically obvious, usually between the 5th and 7th day (Fig. 2), a very superficial incision was made along the original margins of the transplants separating them from the expanding epithelial explants (Fig. 3). Bleeding following this incision was minimal. One end of the strip was picked up with a thumb forceps and the entire transplant peeled off the underlying
RELAY
FIG. 6.
On the right,
FIG. 7.
Freshly
FIG. 8.
The area in Figure
FrG. g.
The
SI
the first recipient site 15 days following transplantation Left, the strips after 8 days on the second the strips.
transpIanted
area
TRANSPLANTATION
strips
The on the upper arm. homografts.
7, 5 days later. Left,
seen in Figure
intended
second
On the right, the first recipient the second site grafted.
The strips were 8, 7 days later. various small raw areas.
again
and 8 days after removal site.
of
recipient
by
site is covered
site after removal peeled
of the strips.
off and used
to cover
FIG. IO. The same area as in Figures 7 to 9. On the right, the first recipient site zo days after transplantLeft, the second site 15 days following grafting and 8 days ation and 15 days after removal of the strips. after removal of the strips.
bed. Bleeding thereafter from the granulation tissue was often intense, bur subsided rapidly under pressure. The peeled-off strips were then wiped free from blood and placed on the next recipient site (Fig. 4). Peeling off and retransplantation hardly bother the patient at all. Histological examination of the peeled-off strips demonstrated indirectly that epithelium had been left behind on the granulations (Fig. 5). Within 6 to 8 days the epithelial explants on the first area consolidated and formed a continuous layer. At the same time the strips had taken on their second location (Fig. 6).
52
BRITISH JOURNAL OF PLASTIC SURGERY
FIG. xI. Histological appearance of a strip that was transplanted and peeled off three times. H &E.
x 200.
The amount of expansion possible is shown in Figures 7 to IO. Note, too, the use of homograft skin to prepare the next recipient site; this enhances the success of the take. Experimentally, we have succeeded in transferring strips up to 4 times. Even after the third removal the histological picture was satisfactory. The corium was slightly oedeThe epidermis was hyperplastic. matous and showed mild mononuclear infiltration. The borderline between the stratum basale and the stratum spinosum was unclear and a marked polymorphism of the cells and their nuclei was observed. Some cells showed perinuclear vacuolisation (Fig. I I). The technique has now been used on 5 patients with extensive deep burns. Altogether 37 transplants were employed. DISCUSSION
We have shown that the thinner the graft, the earlier its epithelium will be transferred to the granulations (Ganzoni and Smahel, 1973). But too thin grafts are easily torn when peeled off and the quarter thickness represents the best compromise. Retransplantation of the strips was performed at intervals of 5 to 7 days and exLarger numbers of cells have perience shows that the 7-day interval is preferable.
RELAY TRANSPLANTATION
53
then migrated on to the granulations, their survival is more certain and growth progresses more rapidly. The retransplanted strips must have intimate contact with the underlying bed. If this is not achieved, epithelium may proliferate on the underside of the transplant. The factor limiting the number of possible retransplantations is, in our experience, not exhaustion of the regenerative capacity of the epidermis but the mechanical tearing Further, in some strips the epidermis became of the strips when peeling them off. detached. Shepard (1972) and Ashbell (1972) have written about “The storage of split skin Our technique could be characterised as the storage of grafts on their donor sites”. split grafts on their recipient sites. The advantage of the recipient area being able to profit from its storage of the grafts is obvious. SUMMARY A method of skin transplantation is presented whereby a wound may be successively sown with epithelium by the repeated transfer of the same strips of split thickness skin. REFERENCES ASHBELL,T. S. (1972). Letter to the Editor: The storage of split skin grafts on their donor sites. Plastic and Recomtructive Surgery, 50, 178-179. BILLINGHAM,R. E. and REYNOLDS,J. (1952-53). Transplantation studies on sheets of pure epidermal epithelium and on epidermal cell suspensions. British Joumal of Plastic Surgery, 5, 25-36.
GANZONI, N. and SMAHEL, J. (1973). Zur Wahl der Transplantatdicke bei der freicn Transplantation von Haut. Helvetica chirtrrgica Acta, 40, 267-269. SHEPARD,G. H. (1972). The storage of split-skin grafts on their donor sites. Plasric amI Reconstructive Surgery, 49, I 15-122.
SMAHEL,J. (1972). The “relay” graft. British youwlai of Plastic Surgery, 25, 432-434. TANNER, J. C., VANDEPUT,J. and OLLEY, J. F. (1964). The mesh skin graft. Plastic: arid Recomtructive
Surgery, 34, 287-292.