Abandoning the SIEA Flap for the Dual-Plane DIEP Reduces Fat Necrosis and Flap Failure.

BACKGROUND: Despite its limitations in abdominally based breast reconstruction, using the superficial inferior epigastric artery (SIEA) flap or system can be advantageous in specific clinical scenarios. To optimize outcomes in these cases, the authors performed a retrospective review of their flap series to advocate a new algorithm to use the superficial system. METHODS: A retrospective analysis was performed on 1700 consecutive free abdominal flaps for the presence of a dominant superficial system or poor deep inferior epigastric artery perforators (DIEP) on clinical examination or angiography. In this setting, the authors analyzed the primary outcome measures of fat necrosis and flap failure with use of the superficial system alone versus a "dual-plane DIEP," where there was an intraflap anastomosis performed between the DIEP pedicle and SIEA pedicle. A multivariable analysis was performed with 21 other potentially confounding variables and compared with outcomes with traditionally perfused DIEP flaps. RESULTS: Fat necrosis was present in 13% of 506 DIEP flaps, 34.1% of 41 SIEA system flaps, and 2.7% of 37 dual-plane DIEP flaps. Superficial system-only flaps were independent predictors of fat necrosis (OR, 6.55; P < 0.001) and flap failure (OR, 9.82; P = 0.002) compared with dual-plane DIEP flaps when used for the same indications. CONCLUSION: In settings of superficial dominance or need to augment perfusion to lateral zones in abdominal free flaps, performing a dual-plane DIEP flap instead of using the superficial system vasculature alone with an SIEA flap can decrease the odds of fat necrosis and flap failure to equal that of a standard DIEP flap. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

A new indication and surgical procedure to reduce fat necrosis after breast-conserving surgery using an inframammary adipofascial flap.

BACKGROUND: There is little information on the risk factors for fat necrosis after breast-conserving surgery using an inframammary adipofascial flap (IAF). METHODS: We conducted a retrospective cohort study from a single institution evaluating the risk factors for fat necrosis after breast-conserving surgery using an IAF (n = 41) performed from 2005 to 2020 for newly diagnosed stage 0-2 breast cancer or phyllodes tumor. RESULTS: Age (≥50 years of age vs. <50 years of age), mammographic density (fatty vs. other) and operation period (before vs. after revision of surgical procedure and patient indication) were significantly associated with fat necrosis (p = 0.006, p = 0.04 and p = 0.02, respectively). CONCLUSION: Our study suggested that the use of an IAF with crescent dermis and selection of appropriate cases for IAF after breast-conserving surgery may be useful for the purpose of reducing fat necrosis. Further study is needed.

The Impact of Indocyanine Green Angiography on Fat Necrosis in Deep Inferior Epigastric Perforator Flap Breast Reconstruction.

BACKGROUND: The deep inferior epigastric perforator flap (DIEP) is a widely known reliable option for autologous breast reconstruction. One common complication of DIEP procedures is fat necrosis. Consequences of fat necrosis include wound healing complications, pain, infection, and the psychological distress of possible cancerous recurrence. Clinical judgment alone is an imperfect method to detect at-risk segments of adipose tissue. Objective methods to assess perfusion may improve fat necrosis complication rates, reducing additional surgeries to exclude cancer and improve cosmesis for patients. METHODS: The authors performed a retrospective review of patients who underwent analysis of DIEP flap vascularity with or without intraoperative indocyanine green angiography (ICGA). Flap perfusion was assessed using intravenous ICGA and was quantified with both relative and absolute value units of fluorescence. Tissue with observed values less than 25% to 30% relative value units was resected. Postoperative outcomes and fat necrosis incidence were collected. RESULTS: Three hundred fifty-five DIEP flaps were included in the study, 187 (52.7%) of which were assessed intraoperatively with ICGA. Thirty-nine patients (10.9%) experienced operable fat necrosis. No statistically significant difference in incidence of postoperative fat necrosis was found between the 2 groups (P = 0.732). However, a statistically significant relationship was found between fat necrosis incidence and body mass index as both a continuum (P = 0.001) and when categorized as greater than 35 (P = 0.038). CONCLUSIONS: Although ICGA is useful for a variety of plastic surgery procedures, our retrospective review did not show a reduction in operable fat necrosis when using this technology.

Intraoperative Assessment of DIEP Flap Breast Reconstruction Using Indocyanine Green Angiography: Reduction of Fat Necrosis, Resection Volumes, and Postoperative Surveillance.

BACKGROUND: This study aims to characterize the effect of laser-assisted indocyanine green fluorescence angiography on fat necrosis and flap failure in deep inferior epigastric artery perforator (DIEP) flap breast reconstruction. METHODS: A retrospective review was performed on 1000 free flaps for breast reconstruction at a single center from 2010 to 2017. Indocyanine green angiography was used after completion of recipient-site anastomoses to subjectively assess for areas of hypoperfusion. A multivariable logistical analysis was conducted with 24 demographic and surgical factors and their effects on fat necrosis and flap failure. RESULTS: Five hundred six DIEP flaps were included in the statistical analyses. Thirteen percent of flaps had fat necrosis. Indocyanine green angiography was used for 200 flaps and was independently associated with a decrease in the odds of fat necrosis (OR, 0.38; p = 0.004). There was no reduction in flap failure rates when using indocyanine green angiography (OR, 1.15; p = 0.85). However, there was a decrease in flap loss with increasing venous coupler diameter (OR, 0.031 per 1-mm increase; p = 0.012). The 84.9-g higher weight of resected tissue before inset without indocyanine green angiography versus the weight of the tissue resected with indocyanine green angiography was statistically significant (p = 0.01). Per single incident of fat necrosis, our cohort underwent an additional 0.69 revision procedures, 1.22 imaging studies, 0.77 biopsies, and 1.7 additional oncologic office visits. CONCLUSION: Intraoperative indocyanine green fluorescence angiography decreases the odds of fat necrosis, saves volume when flap trimming at inset, and can significantly reduce the postoperative surveillance burden in DIEP-based breast reconstruction. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Estimation of Contralateral Perfusion in the DIEP Flap by Scoring the Midline-Crossing Vessels in Computed Tomographic Angiography.

BACKGROUND: In deep inferior epigastric perforator flap surgery, the amount of perfusion achievable in the contralateral side over a midline is unclear. Predicting contralateral perfusion preoperatively using computed tomographic angiography will allow efficient breast reconstruction with decreased complications. The authors used computed tomographic angiography to determine whether contralateral perfusion is related to blood vessel status across the midline. METHODS: Preoperative computed tomographic angiography scans and intraoperative perfusion in patients who underwent breast reconstruction with a deep inferior epigastric perforator flap between January of 2018 and July of 2018 were checked prospectively. A vessel scoring system was prepared according to vessel density across the flap midline on the scan (grade 0, no visible vessels; grade 1, visible vessels with disconnection or could not be judged as grade 0 or 2; grade 2, definite vessels). Intraoperative flap perfusion was confirmed with indocyanine green angiography. Postoperative fat necrosis was analyzed using ultrasonography. RESULTS: Ninety-four patients were analyzed. Mean maximal contralateral perfusion length was as follows: grade 0, 7.50 ± 1.89 cm; grade 1, 7.93 ± 2.01 cm; and grade 2, 10.14 ± 2.29 cm. Grade 2 had a statistically significantly greater contralateral perfusion length than grade 0 (p < 0.001) and grade 1 (p < 0.001). Fat necrosis occurred in 27.3 percent (grade 0), 19.1 percent (grade 1), and 8 percent (grade 2), which was statistically significant (p = 0.035). CONCLUSIONS: A definite vessel connection across the midline (as in grade 2) in preoperative computed tomographic angiography indicates that contralateral perfusion will be sufficiently achieved. This vessel scoring system would be helpful in predicting flap perfusion and planning the surgery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, IV.

Intraoperative Laser-Assisted Indocyanine Green Imaging Can Reduce the Rate of Fat Necrosis in Microsurgical Breast Reconstruction.

BACKGROUND: Fat necrosis following microsurgical breast reconstruction is common and problematic for patients and surgeons alike. Indocyanine green angiography provides a means of evaluating flap perfusion at the time of surgery to inform judicious excision of hypoperfused tissue. The authors hypothesized that incorporation of protocolized indocyanine green-informed flap débridement at the time of surgery would decrease the incidence of fat necrosis. METHODS: A retrospective study of two cohorts was performed evaluating patients before and after implementation of protocolized indocyanine green-guided flap excision. Variables included demographics, procedural details, and complications. Multivariable analysis was used to determine significant differences between the cohorts and evaluate for meaningful changes in fat necrosis. RESULTS: Eighty patients were included, accounting for 137 flaps. Flap type was the only significant difference between the two groups, with the indocyanine green group more likely to be deep inferior epigastric perforator flaps (43.1 percent versus 25.3 percent; p = 0.038). The overall postoperative incidence of fat necrosis was 14.6 percent (20 of 137 flaps). Comparing by cohort, the standard débridement group showed 18 of 79 flaps with fat necrosis (22.8 percent), whereas the indocyanine green-informed débridement group showed only two of 58 flaps with fat necrosis (3.4 percent; odds ratio, 0.11; 95 percent CI, 0.02 to 0.60; p = 0.011). There were no other significant differences in complication profile. CONCLUSIONS: Intraoperative use of indocyanine green angiography was associated with significantly lower odds of fat necrosis. This technology may reduce additional revision operations and improve patient satisfaction. Additional studies are needed to determine whether this innovation is cost-effective and generalizable to the entire autologous breast reconstruction population. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Outcomes of DIEP Flap and Fluorescent Angiography: A Randomized Controlled Clinical Trial.

BACKGROUND: Breast reconstruction with the deep inferior epigastric perforator (DIEP) flap can be associated with complications such as fat necrosis. The authors' objective was to assess the safety and efficacy of fluorescent angiography with indocyanine green to reduce fat necrosis. METHODS: The authors designed a parallel, randomized, controlled clinical trial for unilateral breast reconstruction. The poorly vascularized tissues of the DIEP flap were removed based on a clinical evaluation in group 1 and based on angiographic criteria in group 2. The authors recorded the flap dimensions, perfusion in terms of fluorescence intensity, complications, reoperations, and BREAST-Q questionnaire scores for both groups. RESULTS: The study included a total of 51 patients. The flaps showed no size differences after the tissue was excised. The flaps of group 2 presented higher perfusion rates (p = 0.001). The incidence of fat necrosis was 59.3 percent in group 1 and 8.3 percent in group 2 (p = 0.001). Four cases of partial necrosis were recorded in group 1 (18.2 percent) compared with none in group 2 (0 percent) (p = 0.131). Four patients underwent reoperation in group 1 (14.8 percent) compared with none in group 2 (0 percent) (p = 0.113). The patients in group 2 reported higher scores in all domains of the BREAST-Q. CONCLUSIONS: Fluorescent angiography with indocyanine green significantly reduced the incidence of fat necrosis without diminishing the flaps' dimensions. The perfusion rates were significantly higher and the patients reported significantly greater satisfaction and quality of life. Fluorescent angiography with indocyanine green may be considered a safe and effective tool to enhance the outcomes of breast reconstruction with the DIEP flap. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, I.

Intraoperative Indocyanine Green Angiography for Fat Necrosis Reduction in the Deep Inferior Epigastric Perforator (DIEP) Flap.

BACKGROUND: Fat necrosis is a frequent complication (up to 62.5%) of microsurgical breast reconstruction using the deep inferior epigastric perforator (DIEP) flap. This could have important clinical and psychological repercussions, deteriorating the results and increasing reconstruction costs. OBJECTIVES: The aim of this study was to demonstrate the intraoperative use of indocyanine green angiography (ICGA) to reduce fat necrosis in DIEP flap. METHODS: Sixty-one patients who underwent unilateral DIEP flap procedures for breast reconstruction after oncological mastectomy were included (24 cases with intraoperative use of ICGA during surgery, 37 cases in the control group). The follow-up period was 1 year after surgery. The association between the use of ICGA and the incidence of fat necrosis in the first postoperative year, differences in fat necrosis grade (I-V), differences in fat necrosis requiring reoperation, quality of life, and patient satisfaction were analyzed. RESULTS: The incidence of fat necrosis was reduced from 59.5% (control group) to 29% (ICG-group) (P = 0.021) (relative risk = 0.49 [95% CI, 0.25-0.97]). The major difference was in grade II (27% vs 2.7%, P = 0.038). The number of second surgeries for fat necrosis treatment was also reduced (45.9% vs 20.8%, P = 0.046). The ICG group had higher scores on the BREAST-Q. CONCLUSIONS: Intraoperative ICGA is a useful technique for reconstructive microsurgery that might improve patient satisfaction and reduce the incidence of fat necrosis by half as well as reduce its grade, especially in small fat necrosis cases; consequently, ICGA could reduce the number of secondary surgeries for treatment of fat necrosis.

Optimizing Perforator Selection: A Multivariable Analysis of Predictors for Fat Necrosis and Abdominal Morbidity in DIEP Flap Breast Reconstruction.

BACKGROUND: This study aims to elucidate the important predicting factors for fat necrosis and abdominal morbidity in the patient undergoing deep inferior epigastric artery perforator flap reconstruction. METHODS: The authors conducted a retrospective review of 866 free-flap breast reconstructions performed at one institution from 2010 to 2016. Twenty-eight potential predictors were included in multivariable analyses to control for possible confounding interactions. RESULTS: Four hundred nine total deep inferior epigastric artery perforator flaps were included in the statistical analysis. Of these, 14.4 percent had flap fat necrosis, 21.3 percent had an abdominal wound or complication, and 6 percent had an abdominal bulge or hernia. Analysis showed an increase in the odds of fat necrosis with increasing flap weight (OR, 1.002 per 1-g increase; p = 0.0002). A decrease in the odds of fat necrosis was seen with lateral row (OR, 0.29; p = 0.001) and both medial and lateral row perforator flaps (OR, 0.21; p = 0.001), if indocyanine green angiography was used (OR, 0.46; p = 0.04), and with increasing total flow rate of the flap (OR, 0.62 per 1-mm/second increase; p = 0.05). Increased odds of abdominal bulge or hernia were seen with lateral row or both medial and lateral row perforators (OR, 3.21; p = 0.05) versus medial row perforator-based flaps, and with patients who had an abdominal wound postoperatively (OR, 2.59; p = 0.05). CONCLUSIONS: The authors' results suggest that using larger caliber perforators and perforators from the lateral row alone, or in addition to medial row perforators, can decrease fat necrosis more than simply harvesting more perforators alone. However, lateral and both medial and lateral row perforator flaps come at the cost of increasing abdominal bulge rates. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Breast cancer and fat grafting: efficacy, safety and complications-a systematic review.

Autologous fat grafting (AFG) or lipofilling is nowadays a popular technique for breast reconstruction after breast cancer surgery. There is debate regarding the oncological safety and risks of this procedure in breast cancer patients. A systematic review of the literature published between January first 1995 and October first 2016 was conducted regarding the efficacy, safety and complications of this technique in breast cancer patients after their cancer treatment. The databases PubMed, Science Direct and Thomson Reuters Web of Science were used to search for qualified articles. Inclusion criteria were women with a personal history of breast cancer and at least one lipofilling procedure. Only studies containing a minimum of 20 patients were included in this systematic review. The search yielded a total of 23 suitable articles: 18 case series, 4 retrospective cohort studies and one prospective cohort study. The systematic review encompassed a total of 2419 patients. Medical imaging was used in the majority of the studies to assess the follow-up. Mammography was the most popular technique (65.2%), followed by ultrasound (47.8%) and MRI (30.4%). The prevalence of complications was the following: fat necrosis in 5.31%, benign lesions, like cysts or calcifications in 8.78%, infections in 0.96% and local cancer recurrence in 1.69%. AFG or lipofilling appears to be an oncological safe technique with a low morbidity in women with a history of breast cancer. In order to have a better understanding and evidence of the oncological safety a randomised controlled trial is urgently needed. We further recommend that all AFG be registered in the cancer register.

Dual-Pedicle Flap for Unilateral Autologous Breast Reconstruction Revisited: Evolution and Optimization of Flap Design over 15 Years.

BACKGROUND: In thin patients or when a significant amount of skin is needed, use of the entire abdomen to reconstruct a single breast may be necessary. In this article, the authors present their 15-year experience in dual-pedicle flap evolution and optimization of flap design. METHODS: A retrospective review was conducted of all bipedicle flaps performed from 2000 to 2015. RESULTS: Overall, 57 patients (mean age, 49.2 years; mean body mass index, 26.2 kg/m) underwent dual-pedicle flap reconstruction of a unilateral mastectomy defect. Thirteen patients had a history of smoking, 30 patients had previously undergone irradiation, and 21 patients underwent immediate reconstruction. Eleven bipedicle flaps were performed with a pedicle transverse rectus abdominis musculocutaneous (TRAM) flap coupled to a free TRAM (n = 4), muscle-sparing TRAM (n = 4), or deep inferior epigastric artery perforator (DIEP) (n = 3) flap, and all were performed from 2000 to 2007. The thoracodorsal vessels (n = 8) were used more frequently earlier in the study period with the internal mammary vessels, whereas the antegrade/retrograde internal mammary vessels were used in the remaining patients, except for three patients in whom the internal mammary vessels and an internal mammary vessel perforator were used. Over the study period, there was an increase in the use of DIEP and superficial inferior epigastric artery flaps and the internal mammary vessels as recipients. Complications included delayed wound healing (n = 6), abdominal bulge (n = 2), cellulitis (n = 4), seroma (n = 3), and fat necrosis (n = 4). There was one partial flap loss where the superficial inferior epigastric artery portion of the dual-pedicle flap was lost. CONCLUSIONS: Dual-pedicle free flaps can be performed safely and reliably. Use of DIEP flaps maximizes pedicle length, and the internal mammary vessels can be used reliably in an antegrade and retrograde fashion to perfuse both components of the dual-pedicle flap. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Volumetric Planning Using Computed Tomographic Angiography Improves Clinical Outcomes in DIEP Flap Breast Reconstruction.

BACKGROUND: The present study evaluated outcomes of deep inferior epigastric perforator (DIEP) flap breast reconstruction using volumetric planning-which is preoperative planning based on volumetric data of the breast and flap estimated from computed tomographic angiography. METHODS: A prospective review of three patient cohorts undergoing DIEP flap breast reconstruction from June of 2009 to February of 2015 was performed. Cohort 1 comprised 48 cases in which no volumetric planning was used. Cohort 2 included the next 101 consecutive cases undergoing breast reconstruction according to an algorithm based on volumetric planning. Cohort 3 consisted of the next 109 consecutive cases using a modified algorithm. The inset rate (weight ratio of the inset flap to harvested flap) was estimated during volumetric planning, and specific surgical strategies, such as incorporating multiple perforators, conducting venous augmentation (cohort 2), or harvesting bipedicled flaps (cohort 3), were used with reference to it. Rates of perfusion-related complications were compared. RESULTS: All but one flap survived completely. Fat necrosis occurred in 9.7 percent. Overall, the perfusion-related complication rate was 22.9 percent of cohort 1, 10.9 percent in cohort 2, and 5.6 percent in cohort 3 (p = 0.006). The fat necrosis rates were 19.1, 9.9, and 5.6 percent in cohorts 1, 2, and 3, respectively (p = 0.032). A multivariate analysis demonstrated that volumetric planning had independent benefits for preventing perfusion-related complications (p = 0.003). CONCLUSION: The authors' results suggest that volumetric planning can facilitate elaborate planning and reduce perfusion-related complications, enabling reliable breast reconstruction using DIEP flaps. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

[Latest advances in acute pancreatitis]. / Últimos avances en pancreatitis aguda.

The present article analyses the main presentations on acute pancreatitis at Digestive Disease Week 2015. Arterial pseudoaneurysm is an uncommon complication of acute pancreatitis (incidence 0.7%) and mortality from this cause is currently anecdotal. Diabetes mellitus has little impact on the clinical course of acute pancreatitis, unlike cirrhosis, which doubles the risk of mortality. Intake of unsaturated fat could be associated with an increased severity of acute pancreatitis and is a confounding factor in studies evaluating the relationship between obesity and morbidity and mortality. PET-CT (positron emission tomography-computed tomography) could be a non-invasive tool to detect infection of collections in acute pancreatitis. Peripancreatic fat necrosis is less frequent than pancreatic fat necrosis and is associated with a better clinical course. If the clinical course is poor, increasing the calibre of the percutaneous drains used in the treatment of infected necrosis can avoid surgery in 20% of patients. The use of low molecular-weight heparin in moderate or severe pancreatitis could be associated with a better clinical course, specifically with a lower incidence of necrosis. In acute recurrent pancreatitis, simvastatin is a promising drug for prophylaxis of new episodes of acute pancreatitis. Nutritional support through a nasogastric tube does not improve clinical course compared with oral nutrition.

Is Holm Zone III safe from fat necrosis in medial row perforator-based deep inferior epigastric perforator flaps?

BACKGROUND: This study investigated which zonal tissue would be more secure from the risk of fat necrosis between Holm zones II and III and examined the risk factors of fat necrosis in a clinical series of medial row perforator-based deep inferior epigastric artery perforator (DIEP) flaps. PATIENTS AND METHODS: A retrospective chart review was performed for patients undergoing unilateral breast reconstructions with medial row perforator DIEP flaps. Data regarding patients, operation-related characteristics, and complications including fat necrosis were collected. Fat necrosis was mainly diagnosed by ultrasound examination, and its location was also assessed. RESULTS: A total of 103 cases were analyzed. Fat necrosis was diagnosed in 13.6% of patients and developed more frequently in zone III (7.8%) than in zone II (4.9%). In risk factor analysis, the inset rate, the weight ratio of the inset flap to harvested flap, was significantly associated with the development of fat necrosis. The flaps with inset rates more than 79% showed 16 times higher risk of fat necrosis than those below 79% in multivariate analysis. The incidence of fat necrosis in zone III was significantly increased in the high inset rate group when compared with the low inset rate group, whereas the incidence in zone II did not change. CONCLUSIONS: In unilateral breast reconstruction using medial row perforator DIEP flaps, fat necrosis developed more frequently in zone III than in zone II, and this tendency was more prominent in high inset rate group. Not transferring excessive contralateral tissue including lateral zone III tissue might be helpful for reducing the risk of fat necrosis.

Angiographic delay: a viable alternative to surgical delay.

BACKGROUND: Selective embolization of the inferior epigastric arteries can serve as a method for transverse rectus abdominis musculocutaneous (TRAM) flap delay. The purpose of this study was to determine whether delay by selective arterial embolization is comparable to traditionally surgically delayed TRAM flaps as reported in the literature, in terms of skin and fat necrosis, and to examine whether certain risk factors play a role in TRAM flap fat necrosis despite angiographic delay. METHODS: Retrospective chart review was performed for 88 consecutive patients who underwent unilateral TRAM flap breast reconstruction after selective embolization of bilateral inferior epigastric arteries. RESULTS: Between 1997 and 2009, 88 pedicled TRAM flaps were performed for breast reconstruction in women with a mean age of 49.7 years. No patients had flap skin necrosis or total flap loss. In all, 13.6% patients had TRAM flap fat necrosis. Two patients in the TRAM fat necrosis group (16.7%) had a positive history of smoking, which was a statistically significant risk factor for necrosis (P = 0.048). CONCLUSIONS: Outcomes of pedicled TRAM flaps delayed by selective arterial embolization are comparable to historical controls of those delayed by traditional surgical means (ligation of artery and vein) and better than nondelayed flaps. Smoking remains a significant risk factor for TRAM flap fat necrosis despite the benefit of delay.

Influence of the recipient vessel on fat necrosis after breast reconstruction with a free transverse rectus abdominis myocutaneous flap.

The effect of the selection of recipient vessels on the rate of fat necrosis after microsurgical reconstruction of the breast remains largely unknown. Our aim was to evaluate the incidence of fat necrosis after unilateral breast reconstruction with a free transverse rectus abdominis myocutaneous (TRAM) flap after anastomosis with either the internal mammary vessels or the thoracodorsal artery and vein. Consecutive patients who had unilateral reconstruction with a free, muscle-sparing TRAM flap at two tertiary care centres over a 6-year period were identified. The incidence of fat necrosis, defined as postoperative firmness of 1 cm or more persisting for 3 months or more after anastomosis was calculated. To control for the effect of potentially confounding variables (body mass index (BMI), history of preoperative or postoperative radiation, previous abdominal operation, smoking, and hospital) we did a matched-cohort study. A total of 840 unilateral muscle-sparing TRAM flaps were done using either the internal mammary (n = 109) or the thoracodorsal (n = 731) vessels. Evaluation of the entire cohort showed that the incidence of fat necrosis after the two anastomoses was 13 (12%) compared with 130 (18%), respectively (p = 0.17). To control for the effect of confounding variables, 98 patients who had internal mammary anastomoses were matched 1:1 with 98 patients who had thoracodorsal anastomoses. Pair-wise comparisons showed that the incidence of fat necrosis was significantly higher when the thoracodorsal vessels were used (29; 30%) compared to when the internal mammary vessels were used (12; 12%; p = 0.002). Our results showed that a higher rate of fat necrosis may be seen after muscle-sparing TRAM flap reconstruction after anastomosis to the thoracodorsal vessels than with the internal mammary vessels. The exact mechanisms of this association are unknown and warrant additional investigation.

A novel perfluoroelastomer seeded with adipose-derived stem cells for soft-tissue repair.

BACKGROUND: There is a need for engineered soft tissue in reconstructive surgery, particularly after tumor removal. An ideal implant that will provide structural support and a favorable environment for growing cells is a key element in the process of tissue engineering. Nonbiodegradable materials that become well incorporated within the new tissue are a good solution, but many such materials do not have a surface favorable for cell adherence and proliferation. The authors hypothesized that the modification of the pore size in a novel fluoropolymer would improve the adherence and enhance the proliferation of adipose-derived stem cells. METHODS: Fluoropolymers with two varying pore size ranges were examined. Fluoropolymer compound U48 (pore size, 100 to 180 microm) and fluoropolymer compound P54 (pore size, 10 to 55 microm) were seeded with human adipose-derived stem cells, and cell adherence to the material was measured after 4 hours and cell proliferation was measured after 72 hours. Cell-seeded constructs were implanted subcutaneously in a nude mouse model for 30 days. RESULTS: Fluoropolymer surface treatment with fibronectin improved the attachment of adipose-derived stem cells to the well plates but did not improve attachment to the fluoropolymer, regardless of pore size. Fluoropolymer U48 increases the adherence and provides a favorable surface for proliferation of adipose-derived stem cells. CONCLUSIONS: After subcutaneous implantation into nude mice, tissue growth was observed in the fluoropolymer samples with the larger pore size. The characteristics of this new material will allow for future clinical applications in plastic and reconstructive surgery.

Use of a tourniquet in panniculus resection.

The tourniquet technique is simple and provides an efficacious method for panniculectomy. Time spent during surgery and anesthesia can be offered. Furthermore, less fat necrosis can be anticipated because of the reduced use of electrocautery, which in turn should decrease the risk of seroma formation and infection.