REFINING PERFORATOR SELECTION FOR DEEP INFERIOR EPIGASTRIC PERFORATOR FLAP: THE IMPACT OF THE DOMINANT VENOUS PERFORATOR ANDREAS GRAVVANIS M.D., PH.D., F.E.B.O.P.R.A.S.,1* DIMOSTHENIS TSOUTSOS M.D., PH.D.,1 GEORGE PAPANIKOLAOU M.D.,1 AHMED DIAB M.D.,1 PENELOPE LAMBROPOULOU M.D.,2 and DIMITRIOS KARAKITSOS M.D., DSC., PH.D.3

Introduction: This article aims to investigate the critical role of the venous-perforator in the decision-making process of choosing the best suitable perforator-complex in a deep inferior epigastric perforator (DIEP) flap. Methods: Forty consecutive DIEP breast reconstructions were pre-operatively evaluated by CT-Angiography to identify the dominant and centrally located abdominal wall perforators. The CTA results were used as a guide to conduct a Color-Duplex-Ultrasound examination that was mainly focused on investigating the accompanying venous-perforator. In group-A (n 5 20) perforator-complex selection was based on the size of the arterial-perforator, whilst in group-B (n 5 20) it was based on the size of the venous-perforator. Results: All single perforator-complex DIEP flaps survived. No significant differences were recorded concerning the size of arterial-perforator between the two groups; however the size of venous-perforator was significantly larger in group-B (P < 0.05). In group-A, four flaps showed vascular compromise intraoperative that was salvaged by flap supercharge with the superficial inferior epigastric system. In contrast, in group-B, all flaps were re-vascularized uneventfully (P < 0.05). Physical examination revealed a palpable mass in one patient and ultrasound investigation added three cases with a firm area of scar tissue in group-A, but no fat necrosis was detected in group-B (P < 0.05). Conclusions: The CTA-guided duplex ultrasonography could direct the perforator-complex selection according to the size of the venous-perforator, and may reduce the intraoperative problems and C 2013 Wiley Periodicals, Inc. Microsurgery 34:169–176, 2014. the incidence of fat necrosis. V

Microsurgical

breast reconstruction has become increasingly popular since the introduction of the perforatorbased abdominal flaps.1 The deep inferior epigastric perforator (DIEP) flap remains the gold standard among the microsurgical flaps due to the reduced donor site morbidity, well-concealed donor-site scar, skin, and fat architecture resembling the female breast, and the amount of reliably transferred tissue.2 The reliability of the DIEP branching pattern was introduced by Moon and Taylor in 19883 and was recently demarcated by the in vivo studies of Rozen et al.4 Given the variability of the branching pattern, microsurgeons must be aware about the topography of the perforators, and most importantly must be conscious about the perforator dominance.5,6 The selection of the dominant perforator is based upon its distinctive anatomical characteristics as it is usually centrally located, baring a short intramuscular trajectory and a diameter >1 mm.7 The existence of congenital and acquired anatomical var-

This paper has been presented at the 7th biennial meeting of the World Society for Reconstructive Microsurgery, held in Chicago, Illinois, July 11–14, 2013. 1 Department of Plastic Surgery, Microsurgery and Burn Center “J. Ioannovich,” General State Hospital of Athens “G. Gennimatas,” 11527, Athens, Greece 2 Department of Radiology, General State Hospital of Athens “G. Gennimatas,” 11527, Athens, Greece 3 Intensive Care Unit, General State Hospital of Athens “G. Gennimatas,” 11527, Athens, Greece *Correspondence to: Andreas Gravvanis, 10 Patroklou, Agia Paraskevi, 15343 Athens, Greece. E-mail: [email protected] Received 15 March 2013; Revision accepted 26 August 2013; Accepted 5 September 2013 Published online 15 October 2013 in Wiley Online Library (wileyonlinelibrary. com). DOI: 10.1002/micr.22193 Ó 2013 Wiley Periodicals, Inc.

iations of the DIEP along with the need of accurate preoperative planning require careful pre-operative imaging of the perforator flap. Several imaging techniques have been applied such as handheld Doppler,8 Color-Doppler ultrasound (CDU),9 computed tomographic angiography (CTA),5–7 magnetic resonance angiography,10 as well as stereotactic guidance systems and dynamic infrared thermography.11,12 The main focus of the aforementioned imaging techniques has been the dominant arterial-perforator, which is partially responsible for disregarding the significance of the accompanying venous-tributaries. To date, the term “perforator” has mainly referred to a perforator artery, but recently the concept of the perforator complex, which includes the triad of an arterial perforator, venous tributaries and nerve, in any combination, has been introduced.13 Venous congestion is by far the most common vascular complication of DIEP flap, while various intra- and/or post-operative therapeutic strategies have been previously employed by microsurgeons.14,15 Indeed, the size of the venous-tributary accompanying the dominant arterialperforator might be crucial to minimize flap complications. Our aim was to investigate the impact of the size and patency of the venous conduit in the selection of the dominant perforator-complex. The former was evaluated by the implementation of a complex imaging protocol integrating both CTA and CDU. PATIENTS AND METHODS

Forty women who were candidates for DIEP flap breast reconstruction participated in this prospective study (2009–2012). Inclusion criteria were: unilateral delayed

170

Gravvanis et al.

reconstructions, age ranging between 29–50 years old, and body mass index (BMI) ranging between 27–30 kg/m2. All subjects were otherwise healthy, non-smokers and without any previous history of cardiovascular disease or other comorbidities. Thus, we aimed in creating a rather homogeneous study group in terms of demographic and clinical characteristics. All patients were pre-operatively evaluated by CTA to identify the dominant and centrally located abdominal wall perforators. The CTA results were used as a guide to conduct a CDU examination in all cases. However, CDU was mainly focused on investigating the size and patency of the accompanying venous tributaries. The latter could not be properly assessed by a standalone CTA examination. Thus, the above-mentioned complex imaging protocol was termed as “CTA-guided CDU examination” and was used mainly for venous tributaries mapping. Next, patients were randomly divided in two groups. In group-A (n 5 20) perforator-complex selection was based on the size of the dominant artery, while in group-B (n 5 20) it was based on the size and patency of the dominant vein. The average age in group-A was 38 6 2.2 whilst in group-B was 39 6 2.3 (P > 0.05) and the average BMI in group-A was 28.7 6 1.2 whilst in group-B was 28.4 6 1.8 (P > 0.05), denoting the homogeneity of the two groups. CTA images were assessed by a radiologist (PL) and a plastic surgeon (AG). Two-dimensional and ColorDoppler measurements were performed by a single critical care ultrasound expert (DK), while all flaps were raised by the same surgeon (AG). Informed consent was received for all patients and anonymity was carefully protected. Patients were recruited through a single institution and institutional ethics approval was obtained accordingly. Computed Tomographic Angiography Study

CTA was pre-operatively performed with 16-slice CT scanner in all cases. Patients were placed in a supine position on the CT table, while scans were obtained from the diaphragmatic hiatus to the lesser trochanter in a craniocaudal direction. Scans were obtained after the intravenous administration of 85 mL of Niopam 300 with 30 mL of saline at a flow rate of 4 mL/second. Images were analyzed in a GE Lightspeed 32-slice scanner using the following protocol: KVp 120; MA 150–300; pitch 1.375: 1; Delay time between injection and image acquisition was 25 6 1 seconds;16 acquired slice thickness of 0.625 mm; reconstruction slice thickness of 0.5 mm. Using axial views, we have studied the course of the DIEP from its origin through the muscle to identify the 3–4 optimal arterial perforators with diameters >1 mm (Fig. 1A). A 1 cm grid extending 10 cm laterally on each side, 2 cm cranially, and 8 cm caudally, was drawn Microsurgery DOI 10.1002/micr

Figure 1. (A) Patient 1 (group-B): Axial view of computed tomographic angiography (CTA) to identify the best 3–4, centrally located abdominal wall arterial-perforators. The dominant arterialperforator (arrow) emerges close to the medial border of rectus muscle and pierces the muscular fascia right in the abdominal middle line. (B) Patient 1 (group-B): A 1 cm grid was drawn on the patient’s abdominal wall with the umbilicus in the center, and the position of the arterial-perforators was marked on the abdominal skin of the patient. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

on the patient’s abdominal wall with the umbilicus in the center. Using a virtual coordinate system, all information was transferred to a data form sheet in a format that allowed us to mark the position of the perforators (preoperative mapping) on the abdominal skin of the patient (Fig. 1B). Ultrasound Study

The M-Turbo ultrasound system (SonoSite, Bothell, WA) equipped with a high-frequency (12–20 MHz)

Refining Perforator Selection

linear transducer was utilized to assess blood flow in the complex-perforator as previously described.17 The 3–4 optimal arterial perforators which were previously located by CTA and thus marked on patient’s abdominal skin were subsequently evaluated by two-dimensional and Color-Doppler techniques at their exit point from the abdominal fascia to confirm their patency and normal blood flow (Fig. 2). The vessels were scanned on the longitudinal axis while the operator carefully adjusted the transducer to minimize the angle between the Doppler beam and the long axis of the artery and also to ensure that the sampling volume was located within the vessel lumen for as much of the cardiac cycle as possible. Pertinent two-dimensional and Doppler measurements were

171

performed. Specifically, the diameter of the perforator as well as the pulsatility index (PI 5 systolic velocity 2 diastolic velocity/time-averaged velocity) were assessed as previously described.17 PI reflects the relationship between systolic and diastolic blood velocity waveform components and is a measure of vascular impedance Apart from the study of the arterial conduit, CDU was used to evaluate the accompanying venous tributaries within the perforator-complex (Fig. 2). Venous blood flow was depicted to run in an opposite direction compared to the perforators; notwithstanding the tributaries could be identified mainly due to their characteristic nonpulsatile Color-Doppler waveform. Thus, the discrimination between arteries and veins was not based on color flow (e.g., Blue for vein, red for artery), as the latter can be modified by changing the direction of the probe. Red color represents flow direction towards the probe, whilst blue color signifies flow direction away from the probe. Patent tributaries of larger size (dominant) within the perforator-complex were located. The pre-operative mapping, which was based on arterial and venous conduits, in the two groups of patients, respectively, was projected on the abdominal skin at the end of the imaging studies (Fig. 3A). All ultrasound examinations were performed in an out-patient clinic examination room, under the same environmental conditions during morning hours. Patients were provided with adequate time to relax before the actual ultrasound examination, while noninvasive arterial blood pressure monitoring was employed to ensure that all subjects were normotensive during the ultrasound study. Three ultrasound measurements were performed in all cases and the results were averaged and used in the statistical analysis. Clinical Study

DIEP flap was raised on a standard fashion in all patients, and was based on a single perforator-complex identified and chosen pre-operatively (Fig. 3B). Intraoperative findings and incidents related to flap revascularization (ischemia time, problems with flap perfusion, necessity for flap supercharge) were recorded. Post-operatively, all flaps were evaluated for partial and fat necrosis by clinical criteria and ultrasonography. Ultrasound screening was standardized at 10 months on all patients. Figure 2. Patient 1 (group-B): Concomitant Color DuplexUltrasound studied the good size perforators identified with CTA, focusing on the size of the accompanying venous-perforator. The caliber of the perforating artery was qualitatively estimated at the exit point, and the comitant vein was distinguished from artery by a non-pulsatile flow pattern and an opposite flow direction. (A) Perforator-complex with dominant arterial-perforator (1.22 mm). This perforator-complex links to the arrow on Figure 1. (B) Perforator-complex with dominant venous perforator (1.71 mm). This perforator-complex links to the arrowhead on Figure 1B. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

Statistical Analysis

Summary data are presented as means 6 SD. The Student’s t-test for independent means and v2 analysis were used to evaluate differences between continuous and categorical variables, respectively, when group-A versus group-B patients was compared. A P-value (twosided in all tests) of 1 mm can perfuse any flap, not every associated vein can drain every flap. This article aims to emphasize the critical role of a dominant vein in the perforator complex and to highlight the combined use of CTA and CDU in the decision-making process of choosing the best suitable perforator-complex. While the study might be underpowered, our preliminary results indicate a promising potential of ultrasound-guided mapping in microsurgical operations. Future plans consist of expanding this design to include larger, multi-center studies. In conclusion, contrary to the present belief, a dominant perforator-complex is not synonymous to a dominant arterial-perforator. The implementation of a CTA-guided CDU imaging protocol offers accurate perforator mapping, while facilitating the integration of venous mapping in preoperative microsurgical planning. The above-mentioned imaging data can be used by the multidisciplinary microsurgical team for the demarcation of optimum dominant perforator-complexes. In other words, may support surgeons in minimizing venous complications and may improve the degree of DIEP flap survival.

REFERENCES 1. Allen RJ, Treece P. Deep inferior epigastric perforator flap for breast reconstruction. Ann Plast Surg 1994;32:32–38. 2. Allen RJ, Heitland AS. Autogenous augmentation mammaplasty with microsurgical tissue transfer. Plast Reconstr Surg 2003;112:91– 100. 3. Moon HK, Taylor GI. The vascular anatomy of rectus abdominis musculocutaneous flaps based on the deep superior epigastric system. Plast Reconstr Surg 1988;82:815–832. 4. Rozen WM, Ashton MW, Grinsell D. The branching pattern of the deep inferior epigastric artery revisited in-vivo: A new classification based on CT angiography. Clin Anat 2010;23:87–92. 5. Vandevoort M, Vranckx JJ, Fabre G. Perforator topography of the deep inferior epigastric perforator flap in 100 cases of breast reconstruction. Plast Reconstr Surg 2002;109:1912–1918. 6. Gravvanis A, Dionyssiou DD, Chandrasekharan L, Francis I, Smith RW. Paramuscular and paraneural perforators in DIEAP flaps. Ann Plast Surg 2009;63:610–615. 7. Masia J, Clavero JA, Larran~aga JR, Alomar X, Pons G, Serret P. Multidetector-row computed tomography in the planning of abdominal perforator flaps. Plast Reconstr Surg 2006;59:594–599. 8. Giunta RE, Geisweid A, Feller AM. The value of preoperative Doppler sonography for planning free perforator flaps. Plast Reconstr Surg 2000;105:2381–2386. 9. Blondeel PN, Beyens G, Verhaeghe R, Van Landuyt K, Tonnard P, Monstrey SJ, Maton G. Doppler flowmetry in the planning of perforator flaps. Br J Plast Surg 1998;51:202–209. 10. Neil-Dwyer JG, Ludman CN, Schaverein M, McCulley SJ, Perks AG. Magnetic resonance angiography in preoperative planning of deep inferior epigastric artery perforator flaps. J Plast Reconstr Aesthet Surg 2009;62:1661–1665. 11. Rozen WM, Asthon MW. Improving outcomes in autologous breast reconstruction. Aesthetic Plast Surg 2009;33:327–335.

175

12. Granzow JW, Levine JL, Chiu ES, Allen RJ. Breast reconstruction with deep inferior epigastric perforator flap: History and an update on current technique. J Plast Reconstr Aesthet Surg 2006;59:571– 579. 13. Figus A, Wade RG, Gorton L, Rubino C, Griffiths MG, Ramakrishnan VV. Venous perforators in DIEAP flaps: An observational anatomical study using duplex ultrasonography. J Plast Reconstr Aesthet Surg 2012;65:1051–1059. 14. Sbitany H, Mirzabeigi MN, Kovach SJ, Wu LC, Serletti JM. Strategies for recognizing and managing intraoperative venous congestion in abdominally based autologous breast reconstruction. Plast Reconstr Surg 2012;129:809–815. 15. Ali R, Bernier C, Lin YT, Ching WC, Rodriguez EP, CardenasMejia A, Henry SL, Evans GR, Cheng MH. Surgical strategies to salvage the venous compromised deep inferior epigastric perforator flap. Ann Plast Surg 2010;65:398–406. 16. Cina A, Barone-Adesi L, Rinaldi P, Cipriani A, Salgarello M, Masetti R, Bonomo L. Planning deep inferior epigastric perforator flaps for breast reconstruction: A comparison between multidetector computed tomography and magnetic resonance angiography. Eur Radiol. 2013 Apr 10. [Epub ahead of print]. 17. Gravvanis A, Papalois A, Delikonstantinou I, Pentilas N, Zogogiannis I, Tsoutsos D, Karakitsos D. Changes in arterial blood flow of free flaps after the administration of sildenafil in swine. Microsurgery 2011;31:465–471. 18. Koshima I, Soeda S. Inferior epigastric artery skin flaps without rectus abdominis muscle. Br J Plast Surg 1989;42:645–648. 19. Venkat R, Lee JC, Rad AN, Manahan MA, Rosson GD. Bilateral autologous breast reconstruction with deep inferior epigastric artery perforator flaps: Review of a single surgeon’s early experience. Microsurgery 2012;32:275–280. 20. Teunis T, Heerma van Voss MR, Kon M, Macare van Maurik JF. CT-angiography prior to diep flap breast reconstruction: A systematic review and meta-analysis. Microsurgery 2013 Jul 9. DOI: 10.1002/micr.22119. [Epub ahead of print]. 21. Smit JM, Klein S, Werker PM. An overview of methods for vascular mapping in the planning of free flaps. J Plast Reconstr Aesthet Surg 2010;63:e674–e682. 22. Rozen WM, Phillips TJ, Ashton MW, Stella DL, Gibson RN, Taylor GI. Preoperative imaging for DIEA perforator flaps: A comparative study of computed tomographic angiography and Doppler ultrasound. Plast Reconstr Surg 2008;121:9–16. 23. Scott JR, Liu D, Said H, Neligan PC, Mathes DW. Computed tomographic angiography in planning abdomen-based microsurgical breast reconstruction: A comparison with color duplex ultrasound. Plast Reconstr Surg 2010;125:446–453. 24. Rozen WM, Ashton MW, Stella DL, Phillips TJ, Taylor GI. The accuracy of computed tomographic angiography for mapping the perforators of the DIEA: A cadaveric study. Plast Reconstr Surg 2008;122:363–369. 25. Mathes DW, Neligan PC. Current techniques in preoperative imaging for abdomen-based perforator flap microsurgical breast reconstruction. J Reconstr Microsurg 2010;26:3–10. 26. De Bono DP, Samari NJ, Spyt TJ, Hart S, Horne T, Thrush AJ, Evans DH. Transcutaneous ultrasound measurement of blood flow in internal mammary artery to coronary artery graft. Lancet 1992;330: 379–381. 27. Gravvanis A, Karakitsos D, Dimitriou V, Zogogiannis I, Katsikeris N, Karabinis A, Tsoutsos D. Portable duplex ultrasonography: A diagnostic and decision-making tool in reconstructive microsurgery. Microsurgery 2010;30:348–353. 28. Aubry S, Pauchot J, Kastler A, Laurent O, Tropet Y, Runge M. Preoperative imaging in the planning of deep inferior epigastric artery perforator flap surgery. Skeletal Radiol 2012; Jun 24 [Epub ahead of print]. 29. Cina A, Salgarello, Barone-Adesi L, Rinaldi P, Bonomo L. Planning breast reconstruction with deep inferior epigastric artery perforating vessels: Multidetector CT angiography versus color Doppler US. Radiology 2010;255:979–987. 30. Pellegrin A, Stocca T, Belgrano M, Bertolotto M, Pozzi-Mucelli F, Marij Arnez Z, Cova MA. Preoperative vascular mapping with

Microsurgery DOI 10.1002/micr

176

Gravvanis et al.

multislice CT of deep inferior epigastric artery perforators in planning breast reconstruction after mastectomy. Radiol Med. 2012 Oct 22. [Epub ahead of print]. 31. Schieda N, Fasih N, Shabana W. Triphasic CT in the diagnosis of acute mesenteric ischaemia. Eur Radiol. 2013 Mar 8. [Epub ahead of print]. 32. Gravvanis A, Delikonstantinou I, Karonidis A, Tsoutsos D. Strategies for recognizing and managing intraoperative vascular insufficiency in

Microsurgery DOI 10.1002/micr

abdominal based autologous breast reconstruction. Plast Reconstr Surg 2012;130:743–744. 33. Alonso-Burgos A, Garcia-Tutor E, Bastarrika G, Cano D, MartınezCuesta A, Pina LJ. Preoperative planning of deep inferior epigastric artery perforator flap reconstruction with multislice-CT angiography: Imaging findings and initial experience. J Plast Reconstr Aesthet Surg 2006;59:585–593.

Refining perforator selection for deep inferior epigastric perforator flap: the impact of the dominant venous perforator.

This article aims to investigate the critical role of the venous-perforator in the decision-making process of choosing the best suitable perforator-co...
476KB Sizes 0 Downloads 0 Views