Invited Discussion

The authors present a technical modification of the A-V loop principle, which was first mentioned in the literature by Acland,[1] Germann,[2] and others.[3] [4] They perform extracorporal arteriovenous loops to save operation time, to make the operations easier, and to achieve better cosmetic results at the recipient site.

This is an interesting idea. However, several questions remain unanswered, and the authors' conclusions seem not necessarily warranted by the cases demonstrated.

Filling the vein graft with heparinized saline does not necessarily prevent torsion of the vein graft that may occur, when the blood flows into the graft. Well-planned conventional A-V loops can also easily be performed with a two-team approach to save operation time. So the question has to be asked: How much time is really saved by the method described? 3. Additional disfiguring incisions from the defect to the anastomotic site of the A-V loop are not necessary. The A-V loop that is connected to the recipient major feeding vessels can be passed to the defect in a subcutaneous tunnel, in the same way the authors did it with the performed extracorporeal loop. 4. In the head and neck area, it is sometimes more tedious to expose the recipient vessels for the A-V loops, especially in cases of prior radiation. Arterial anastomosis may be difficult due to severe arterial occlusive disease. In these situations, I found it much more comforting to have accomplished these anastomoses, and then to have a comparatively ``easy'' end-to-end anastomosis to the flap pedicle.

Despite these concerns, the presented technique may still be an interesting alternative in cases where a two-team approach is not feasible, due to the proximity of the defect, and the vein graft and/or flap harvest site.

REFERENCES

• 1 Acland R D. Refinements in lower extremity free flap surgery.  Clin Plast Surg. 1990;  17 733-744
• 2 Germann G, Steinau H U. Reliability of vein grafts in high risk free flap transfer.  J Reconstr Microsurg . 1996;  21-26
• 3 Taub P J, Chun J K, Zhang W X, Pham N D, Silver L, Weinberg H. Staging arteriovenous fistula loops for lengthening of free-flap pedicles.  J Reconstr Microsurg . 1999;  15 123-125
• 4 Choi M L, Hirigoyan M B, Zhang W X, Weinberg H, Silver L, Chun J K. Increased patency of artificial microvascular grafts using arteriovenous fistula loops, a two stage procedure for lengthening the pedicle of free-tissue transfer.  J Reconstr Microsurg . 1996;  12 283-290