Strauch’s Technique for Epigastric Free Flaps in Rats Revisited: A Simple and Effective Method to Increase Patency Rates Elaine Kawano Horibe, M.D., 1,2 Justin Michael Sacks, M.D., 1,2 Ali Emre Aksu, M.D., 4 Jignesh Unadkat, M.R.C.S., 1,2 Dennis Yong Song, M.D., 1 Lydia Masako Ferreira, M.D., Ph.D., 5 Maryam Feili-Hariri, Ph.D., 1,2,3 and W.P. Andrew Lee, M.D. 1,2 ABSTRACT Described by Strauch and Murray in 1967, the rodent epigastric free flap remains a versatile tool for microsurgery research and training. We report herein three sequential phases of our quest to improve efficiency and effectiveness of the original technique, making it more accessible to more microsurgeons. Ninety-six allotransplants were per- formed. Surgical technique, complication rates, clinical findings, and histopathologic correlation of each phase are reported. In phase I, two experienced microsurgeons employed the original technique and succeeded in 77% of the procedures. In phase II, two junior microsurgeons achieved a patency rate of 16.6% using the same technique, as opposed to 100% in phase III, utilizing the not-yet-described simplified flow-thru technique. Although patency rate using the original method varies from 9 to 78% (according to other reports), this technical modification can increase even the less experienced microsurgeons’ success rates, perpetuating the use of Strauch’s epigastric flap in experimental microsurgery. KEYWORDS: Epigastric flap, flow-thru, microsurgery Initially described by Strauch and Murray in 1967, the epigastric free flap rapidly evolved into a ubiquitous method allowing for the investigation of new microsurgical techniques, 1 assessment of vasodilator agents, 2 and study of the delay phenomenon. 3 Further- more, as skin tolerance in composite tissue transplanta- tion has been a difficult topic of investigation, this model has facilitated the evaluation of skin immunological reactions in transplantation, due to its large cutaneous component. Given these advantages, our laboratory was greatly interested in reliably reproducing this model. However, during our attempts, we obtained only sub- optimal results due to technical difficulties, which are faced by other investigators as well. 4–8 As a result, researchers have utilized alternative microsurgical tech- niques, such as end-to-end anastomoses of epigastric vessels, which yielded moderate patency rates of 75%. 7,9 This article reports the experience of our labora- tory with the free epigastric skin flap in rats, first 1 Division of Plastic Surgery, Department of Surgery, 2 Thomas E. Starzl Transplantation Institute, 3 Department of Immunology, University of Pittsburgh, Pittsburgh Pennsylvania, 4 Division of Plastic Surgery, Hacettepe University, Hacettepe, Turkey; 5 Division of Plastic Surgery, Federal University of Sao Paulo, Sao Paulo, Brazil. Address for correspondence and reprint requests: Elaine Kawano Horibe, M.D., Division of Plastic Surgery, Universidade Federal de Sa ˜o Paulo, Rua Napolea ˜o de Barros, 715, 48 Andar, Sa ˜o Paulo. CEP. 04024-002, Brazil. J Reconstr Microsurg 2007;23:321–328. Copyright # 2007 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel: +1(212) 584-4662. Published online: October 31, 2007. DOI 10.1055/s-2007-992651. ISSN 0743-684X. 321 Downloaded by: Hacettepe University. Copyrighted material.