Search

Microscope-integrated indocyanine green near-infrared videoangiography (ICGA) is a new imaging technique to assess vascular flow through diminutive vessels used in microvascular surgery. The purpose of this investigation was to evaluate the diagnostic accuracy of ICGA in detecting microvascular thrombosis in reexploration surgery. Patients undergoing emergent reexploration surgery after free tissue transfer were enrolled in this clinical study. After the patients had been returned to the operating room the pedicle vessels were exposed and a microangiography was performed. Independent of the result, the anastomoses were opened and surgically explored. Sensitivity and specificity was calculated, using the result of exploration surgery as a reference standard. Of 200 free flaps 20 (10%) underwent reexploration surgery. The most common surgical finding was microvascular thrombosis (55%). In one case vascular compromise was due to confusion of artery and vein with anastomosis of two veins. In 40% of patients an intact vascular pedicle was found. The sensitivity and specificity of ICGA to detect microvascular thrombosis was 100% and 86%, respectively. ICGA provides an excellent diagnostic accuracy for detecting microvascular thrombosis in reexploration surgery. Routine implementation of this technique may expedite a correct diagnosis and facilitate the surgical approach by preventing unnecessary surgical manipulation of intact anastomoses., (Thieme Medical Publishers.)

Background: Microscope-integrated indocyanine green near-infrared videoangiography (ICGA) is a new method for the intraoperative assessment of vascular flow through microvascular anastomoses. The intrinsic transit time (ITT) describes the time period from the dye appears at the arterial anastomosis (t(1)) till it reaches the suture line of the venous anastomosis (t(2)). As the transit time reflects blood flow velocity within the flap, prolonged ITT might correlate with low blood flow and a higher rate of postoperative thrombosis. We performed a clinical trial evaluating the association between intraoperative free flap transit time and early anastomotic complications in elective microsurgery., Methods: One hundred consecutive patients undergoing elective microsurgical procedures underwent intraoperative ICG angiography (ICGA). In patients with anastomotic patency, angiograms were retrospectively reviewed and the intrinsic transit time was calculated. Postoperative outcome was registered and compared with the ITT. End points included early reexploration surgery and flap loss within the first 24 hours after surgery., Results: Fourteen patients were excluded from the study due to technical anastomotic failure. The overall flap failure rate was 6% (5/86); the incidence of early re-exploration surgery was 10% (9/86). With a median of 31 seconds patients with an uneventful postoperative course showed significantly shorter ITTs than patients with flap loss or early postoperative reexploration (median: >120 seconds). An optimal cut-off value of ITT > 50 seconds was determined to be strongestly associated with a significantly increased risk of at least one positive end point., Conclusions: This study demonstrates a significant predictive value of the intrinsic flap transit time for the development of flap compromise and early re-exploration surgery., (Copyright 2009 Wiley-Liss, Inc. Microsurgery, 2010.)

Background: : Technical problems at the site of the anastomosis compromise an underappreciated proportion of microsurgical free tissue transfers. Intraoperative identification of technical errors may be able to prevent reexploration surgery and early flap failure. We report the first human study on a new microscope-integrated fluorescence angiography technique, which allows for intraoperative imaging of the anastomotic site., Methods: : Fifty consecutive patients undergoing reconstructive microsurgical procedures were enrolled in the study. Intraoperative near infrared indocyanine green videoangiography (ICGA) was performed on all microsurgical anastomoses, after they had been assessed by the operating surgeon by conventional clinical patency tests. Anastomoses deemed to be occluded by the ICG-angiography were intraoperatively revised, and the result of revision was compared with angiographic findings., Results: : In 11/50 (22%) of patients, where the surgeon had classified the anastomoses as patent, microangiography identified a total luminal occlusion (six) and/or significant alterations in blood flow (five), potentially predisposing toward postoperative flap failure. Intraoperative revision confirmed angiographic findings in 100% of cases, and was always associated with flap survival. The decision not to revise despite anastomotic occlusion by the intraoperative angiogram was always followed by flap loss or early reexploration. A delayed return of venous blood from the flap predisposed toward postoperative flap failure., Conclusions: : Hand-sewn anastomoses are subject to technical errors, and conventional patency tests have a low sensitivity for revealing anastomotic failure. Microscope integrated microangiography is an excellent method for identifying significant anastomotic problems, which would have otherwise gone unnoticed. The potential impact on early flap failure and reexploration surgery is considerable. (c) 2009 Wiley-Liss, Inc. Microsurgery 2009.

Background: The vascular territory of the superficial inferior epigastric artery (SIEA) remains to be clarified. The SIEA flap has traditionally been classified as a hemiabdominal flap, but recent evidence points to the fact that a sizable superficial artery is capable of supplying the entire abdominal ellipse., Methods: Twenty-five patients who met the anatomical criteria for undergoing SIEA flap surgery were studied. The abdominal flap was raised on a superficial inferior epigastric pedicle; the dominant musculocutaneous perforators were preserved and clamped above the abdominal fascia on either side. The vascular territory of the superficial epigastric artery and the contribution of the deep epigastric system were visualized using laser-induced fluorescence of indocyanine green. The surgical technique was modified (SIEA, deep inferior epigastric perforator, or bipedicle) based on perfusion measurements and the indication for surgery., Results: The SIEA vascular territory did not cross the midline in 16 patients (64 percent), and ranged from 0 percent (two patients) to the entire abdominal ellipse (five cases). Fourteen patients (56 percent) were operated on with a unipedicle SIEA flap, five patients (20 percent) were operated on with a bipedicle flap, and in six (24 percent), a conventional deep inferior epigastric perforator flap was used. As a SIEA flap was originally intended in all patients, intraoperative perfusion measurements changed the surgical plan in 11 patients (44 percent)., Conclusions: The SIEA angiosome is variable and ranges from 0 to 100 percent of the lower abdominal flap. Intraoperative perfusion measurements are indispensable for evaluating the sufficiency of this pedicle for tissue transfer, especially if the contralateral flap zones are needed for reconstruction.

Unlabelled: Following the TRAM and the DIEP the SIEA flap is the next logical step to reduce the donor site morbidity in autologous breast reconstruction. The vascular axis of the SIEA flap, however, is completely different from the deep epigastric pedicle, on which previous lower abdominal flaps were based. Therefore, a mapping of the vascular territory, which can be reliably harvested on this pedicle, seems mandatory before this new technique can become established., Aim: To chart the angiosome of the superficial inferior epigastric artery with regard to breast reconstruction and to evaluate the random extension of the vascular territory, which can be reliably raised on this pedicle., Study Design: Clinical, prospective study in a university-affiliated department of plastic surgery., Patients: Ten patients undergoing autologous breast reconstruction with the superficial inferior epigastric perforator flap and five patients undergoing aesthetic abdominoplasty with isolation of the abdominal flap on the superficial epigastric vessels., Material and Methods: After isolation of the abdominal panniculus on a single superficial inferior epigastric artery pedicle, the flap was divided in the four conventional zones according to Hartrampf. Perfusion in each of the four zones was measured on the table using the technique of dynamic laser-fluorescence videoangiography., Results: Perfusion of Hartrampf Zone III occurred first (25s post-injection) and the perfusion index amounted median 89% of reference. Perfusion of Zone I occurred median 5s later and the relative perfusion was 80%. Perfusion of the contralateral zones II and IV was dramatically reduced to 8% and zero, respectively, and this reduction was statistically significant (p<0.0001)., Conclusion: The true angiosome of the superficial epigastric artery is located laterally on the ipsilateral hemiabdomen. Its random extension is unreliable and ranges most frequently only to the midline. Based on the results of this study, survival of the skin and subcutaneous fat taken laterally to the border of the contralateral rectus sheath seems questionable. Therefore, the versatility of the SIEA flap for autologous breast reconstruction seems limited when compared with the conventional methods based on the deep inferior epigastric system.

Background The number of venous anastomoses advisable for a free flap continues to be controversial. Intrinsic transit time (ITT) is the time it takes dye during indocyanine green (ICG) microangiography to travel from the arterial to the venous anastomosis. ITT provides information on blood flow velocity and can predict postoperative circulatory complications. This study investigated the effect of the number of venous anastomoses on ITT. Methods The study enrolled 126 patients who had undergone microsurgical reconstruction and intraoperative ICG microangiography. Selection was limited to free gracilis and anterolateral thigh flaps as flaps with a single venous system. The retrospective assessment included reconstruction characteristics of the flaps, clinical outcome, ITT, and the number of venous anastomoses. Results The two groups were homogenous in terms of reconstruction characteristics. The single-venous anastomosis group (n = 75) had a reduced ITT (23.6 ± 11.7 vs. 43.8 ± 23.7 seconds; p < 0.001) compared with the double-anastomosis group (n = 51). A shorter ITT resulted in a significant reduction in the risk of reexploration for anastomotic thrombosis (OR 0.96; p = 0.024). Despite this, a higher reexploration rate tended to occur in the single-venous anastomosis group (9.3 vs. 7.8%; p = 1.0). Conclusion The results highlight the effect of shortening the ITT (thromboprotective blood flow acceleration) by using only one venous anastomosis. However, if the ITT is already at a low enough level with two veins, restriction to one vein does not appear to result in a reduced reexploration rate. For these flaps, the advantages of double-venous anastomosis prevail in terms of a backup drainage. [ABSTRACT FROM AUTHOR]