Assessment of the patency of microvascular anastomoses using microscope-integrated near-infrared angiography: a preliminary study.

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.

Interindividual variability of the SIEA Angiosome: effects on operative strategies in breast reconstruction.

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.

The versatility of the SIEA flap: a clinical assessment of the vascular territory of the superficial epigastric inferior artery.

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.

Secretory phenomena in the non-lactating human mammary gland.

The normal non-lactating premenopausal human mammary gland has been shown by immunohistochemistry and transmission electron microscopy to secrete a number of antimicrobial peptides such as beta-defensins, the cathelicidin LL37, lactoferrin and adrenomedullin. In addition, the non-lactating gland elaborates a prominent glycocalyx at the apical membrane of the glandular epithelial cells, parts of which are shed into the lumen of endpieces and ducts. This glycocalyx includes the mucins MUC 1 and MUC 4, a strongly Alcian Blue positive palyanionic component and sulfated material stained with Aldehyde Fuchsin. MUC 1 and the Alcian Blue positive material are considered to play an antimicrobial role, too. Lactalbumin and lipid droplets also occur in the non-lactating gland. At the EM-level secretory phenomena operating by exocytosis and by means of the apocrine mechanism have been observed. Cytoskeletal components presumably play a role in apocrine secretion. Apart from secretion at the cellular apex, secretion at the cellular basis also occurs regularly, which may represent the production of para- or endocrine factors.

Perfusion zones of the DIEP flap revisited: a clinical study.

BACKGROUND: The Hartrampf perfusion zones of the lower abdominal flap are generally accepted. They were empirically based on the clinical impression of the perfusion in the first 16 unipedicled transverse rectus abdominis musculocutaneous flaps and have been uncritically adopted for the free transverse rectus abdominis musculocutaneous and the free deep inferior epigastric perforator (DIEP) flap. Scientific data proving the validity of these perfusion zones do not exist. The objective of this study was to evaluate and quantitatively assess the perfusion zones of the DIEP flap. METHODS: In a clinical, prospective study of 15 patients undergoing DIEP flap breast reconstruction, tissue perfusion was intraoperatively assessed using the method of laser-induced fluorescence of indocyanine green. RESULTS: Perfusion of zones I, II, and III was seen 25, 41, and 32 seconds, respectively, after injection, and the perfusion index constituted 76, 25, and 47 percent (median) of normal tissue. Perfusion of zone IV was completely absent in five patients (33 percent); in the remaining patients, it was dramatically decreased (5 percent) and occurred with a delay of 67 seconds. CONCLUSIONS: On the basis of the results of this study, the Hartrampf concept of a centrally perfused skin ellipse with declining perfusion of its peripheral ends is wrong and should be revised. Instead, one should think of the lower abdominal flap as two halves separated by the midline. The ipsilateral half has an axial pattern of perfusion; the contralateral half shows a random-pattern, individually variable blood supply. Therefore, the classic Hartrampf zones should be rearranged, switching zones II and III.

Effects of aesthetic abdominoplasty on abdominal wall perfusion: a quantitative evaluation.

Abdominoplasty procedures involve a high risk of early complications, including hematomas, seromas, necrosis, and wound-healing problems. Their rationale is evident from the vascular anatomy of the abdominal wall, as traditional abdominoplasty includes a division of the main perforating vessels. No studies exist to quantitatively assess the consequences of abdominoplasty on the perfusion of the random pattern abdominal flap. To address this issue and quantify the influence of classic abdominoplasty on the perfusion of the abdominal skin, the authors performed a prospective clinical trial including 15 low-risk patients undergoing abdominoplasty for aesthetic purposes. Perfusion of the abdominal flap was measured intraoperatively using the technique of dynamic laser-fluorescence-videoangiography. In the region between the umbilicus and the transverse scar (zone 1), the increment of fluorescence (the slope of the intensity curve during inflow of the indocyanine green) was recorded and compared with the intensity curve of normal tissue that was not involved in surgery (thoracic wall). The results of the intraoperative indocyanine green perfusography showed a significant impairment of the vascular supply of zone 1 in all patients. The mean perfusion index in this region was 17.2 percent (range, 5 to 32 percent) of the perfusion of the surrounding skin that was not involved in surgery. The complication rate was 33 percent (five patients) and included two cases of hematoma and three cases of scar dehiscence with skin and/or fat necrosis. These data indicate that conventional abdominoplasty including extended undermining and division of the superficial and the deep arterial systems causes profound devascularization of the abdominal flap. This might explain the high incidence of complications following this procedure.

Adrenomedullin in mammalian and human skin glands including the mammary gland.

Adrenomedullin is a peptide that has been ascribed numerous functions. In the present paper, adrenomedullin has been localized immunhistochemically in a variety of skin glands of humans, elephants and impalas: apocrine scent glands, eccrine sweat glands, holocrine glands and mammary glands. In the apocrine glands expression of adrenomedullin varied with respect to staining intensity and intracellular localization. In general, glands which appeared to be actively secreting were more strongly stained than quiescent glands. However, within a single glandular tubule, individual cells differed considerably in the staining intensity of adrenomedullin. Adrenomedullin was present in both non-lactating and lactating mammary secretory epithelia, both ducts and alveoli reacted positively. In human mammary glands displaying apocrine metaplasia, the apical protrusions were strongly positive. Furthermore, positive immunostaining was found in endothelium and often in smooth muscle cells of small arteries and veins and in mast cells as well. Many of the adrenomedullin-positive epithelial cells were most strongly stained in the area of the Golgi apparatus, the cellular apex and particularly close to the basal side of the cell membrane. This pattern suggests packaging of adrenomedullin into secretory granules and secretion both at the apex of cells and at their basis. The first form of secretion suggests exocrine secretion, the latter form endocrine secretion of adrenomedullin. A possible hormonal function is in line with basally located electron dense small secretory granules, which have been found by electron microscopy in the glandular epithelia studied.