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At operation wounds to be grafted are excised down to the underlying fascia and haemostasis is secured. A square piece of cork measuring 42x42 mm with thickness 2 mm is covered with a split skin autograft, dermal size down. Smaller graft remnants are also suitable by placing them on the corkplate like a "puzzle". The cork, covered with graft, is then placed in a cutting machine.

The machine contains 13 parallel circular knives. The corkplate with the graft on it, is passed through the dermatome, where the knives cut through the graft, but not through the cork. Thus the graft is cut into 14 stripes 3 mm wide. After the first pass, the cork is rotated 90° and passed through the dermatome for the second time, thus cutting the graft into 14x14 pieces measuring 3x3 mm. Then the corkplate, with the cut graft in place, is removed from the machine .

The upper (epidermal) surface of the graft is sprayed with an adhesive dressing spray (Leukospray, Beiersdorf GmbH, Germany) and allowed to become tacky. The cork plate, covered with graft and adhesive is then pressed onto a prefolded polyamide gauze, which is folded on an aluminium foil backing into 14x14 square pleats, corresponding to the cuts in the autograft.

After this the cork is gently removed, leaving the graft islands adhering to the gauze(Photo1). The gauze is pulled out by firm traction on all four sides, until the pleats become completely unfolded (photo 2 and 3). Finally the aluminium backing is peeled off, to leave the expanded gauze with the separated adherent autograft islands ready for transplantation. After trimming the margins, the gauze is applied, graft side down, to the wound bed and secured with surgical staples. After about 6 days the grafts have grown sufficiently into the wound bed to allow removal of the gauze, leaving the autograft islands in situ on the wound. In the surgical procedure as described by Kreis et.al. (1989) the grafts are then covered with an overlay of allografts, meshed 1:1,5 and secured with a porous, semi-transparent polyamide sheeting. After a further 6 days the sheeting is removed. Daily dressings are continued until epithelialization is complete.

Photo 1

Photo 2

Photo 3

In 1958 a remarkable technique for expanding autografts was described by C.P. Meek. With a Meek-Wall dermatome postage stamp autografts were obtained and expanded using double pleated gauzes. In this way a regular distribution of autograft islands was achieved with a ninefold expansion. This technique however became eclipsed by the introduction of mesh skin grafts (Tanner et al., 1964) and production of dermatome and gauzes was discontinued.

However, lack of autograft donor sides is increasingly encountered as a limiting factor in achieving wound closure in case of extensive skin defects. The Meshgraft technique requires donor sites of suitable size and shape and epithelialization may be delayed with expansion ratios greater than 1:6. Besides widely expanded meshed autografts might become unmanageable.

In close cooperation with Red Cross Hospital Beverwijk, The Netherlands, Humeca redesigned the Meek technique. Imperfections of the original method were overcome and the prefolded gauzes can now be manufactured with expansion ratios 1:3, 1:4, 1:6 and 1:9.

The clinical results with this modified MEEK technique are excellent: the graft take appeares to be excellent, even in problematic zones and even in case of a qualitative inferior wound bed. Only very small donorsites are required. Any small piece of patients skin can be used. The graft islands are close together in a regular pattern, resulting in fast epithelialization. As the autograft islands are not mutually connected, failure of a few islands does not necessarily affect the overall graft take.

The method appears to be a simple technique to achieve a regular distribution of postage stamp grafts, correctly orientated on the wound surface. The cosmetic results are comparable to those obtained with meshgrafts 1:3.

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