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

Using ICG to Streamline Perforator Selection in DIEP Flap Reconstruction: Retrospective cohort study of outcomes in our first one hundred flaps

The use of indocyanine green in conjunction with near infra-red fluoroscopy as an adjunct to the clinical assessment of tissue perfusion is now well established.1-3 Its intraoperative use in breast reconstruction with deep inferior epigastric (DIEP) flaps has been described since 2009.4-6 Fat necrosis is commonly encountered in the recovery period. This study reports on our step-by-step practical technique of using indocyanine green (ICG) to streamline perforator choice intraoperatively during DIEP flap raising for breast reconstruction and our rates of fat necrosis (8%) and flap survival (100%) within the first 100 flaps in our regional reconstruction unit. We discuss the benefits and pitfalls of using ICG fluoroscopy at various stages of breast reconstruction with free DIEP flaps. This study has been reported using the STROBE guidelines.

Postoperative complications in breast reconstruction with deep inferior epigastric perforator flap: Looking for evidence

INTRODUCTION

This study investigated patient- and surgery-related risk factors of postoperative complications in microvascular breast reconstruction with deep inferior epigastric perforator (DIEP) flaps.

METHODS

We reviewed the retrospective charts of 212 patients who underwent 250 DIEP flap breast reconstructions between 2018 and 2023. Patient-related factors included demographic characteristics, comorbidities, radiation therapy, and chemotherapy. Surgery-related factors included reconstructive timing and laterality, perforator choice, venous anastomosis technique, and postoperative acetylsalicylic acid (ASA). Early flap complications (first postoperative week) included flap loss, venous congestion, and hematoma. Late flap complications (after the first postoperative week) included wound dehiscence, skin necrosis, fat necrosis, and infection. Donor-site complications (all late) included wound dehiscence, skin necrosis, infection, seroma, and bulging.

RESULTS

The overall complication rate was 31.1%, and flap loss was 1.9%. Obesity and diabetes were significantly associated with late flap complications and donor-site complications (dehiscence, infection, fat necrosis, and seroma). Radiation therapy showed trends toward greater total flap loss, take back, and flap skin necrosis. Age, hypertension, smoking, and chemotherapy were not associated with higher complications. Harvesting multiple versus a single perforator was associated with significantly more donor-site complications. There were significantly more early flap complications and a trend toward more bulging with lateral versus medial row perforators. Venous anastomosis with a coupler versus a suture showed significantly lower flap complications. Reconstruction timing, laterality, vein number, and ASA use did not impact outcomes.

CONCLUSION

Complications increased by obesity, diabetes, radiation therapy, and the use of multiple and lateral row perforators, as well as sutured venous anastomoses. Conversely, outcomes were not affected by age, hypertension, chemotherapy, reconstructive laterality and timing, vein number, coupler size, or postoperative ASA use.

Laser Speckle Flowgraphy Can Support Intraoperative Assessment of Deep Inferior Epigastric Perforator Flap Blood Flow With Indocyanine Green

Background

Accurately evaluating cutaneous blood flow during the elevation of a deep inferior epigastric perforator (DIEP) flap may reduce postoperative complications in breast reconstruction surgery. This study examined whether laser speckle flowgraphy (LSFG) could be used to help objectively identify the safe areas of DIEP flaps.

Methods

Forty-eight patients who underwent unilateral breast reconstruction with a DIEP flap at Shinshu University Hospital between 2020 and 2024 were prospectively studied. During flap elevation, skin blood flow throughout the flap was measured using LSFG and compared with results obtained by indocyanine green (ICG) angiography. The cohort was also divided according to the number and location of perforators, and an intergroup comparison was performed according to LSFG readings.

Results

In all subjects, relative LSFG blood flow in zones 2 (89.1%) and 3 (87.9%) was comparable, whereas blood flow in zone 4 (72.8%) was significantly lower than in those areas (both P < 0.001). In the lateral row group, blood flow in zone 2 tended to be lower and in zone 3 tended to be higher than in the medial row group (zone 2: 82.6% versus 89.5%, zone 3: 93.6% versus 86.8%). LSFG values did not differ significantly in relation to perforator number. LSFG-determined blood flow in the stained side of the ICG-determined staining border was significantly higher than in the nonstained side (80.6% versus 71.4%, P < 0.001).

Conclusions

LSFG enables objective, noninvasive evaluation of safety margins in DIEP flaps that may support ICG angiography. Safe zones may vary depending on the location of the selected perforator.

Use of Ambient Light Compatible Fluorescence-Guided Surgical Technology for Objective Assessment of Flap Perfusion in Autologous Breast Reconstruction

BACKGROUND

 Decreased autologous flap vascular perfusion can lead to secondary procedures. Fluorescence angiography during surgery reduces the probability of repeat surgery but suffers from interpretation variability. Recently, the OnLume Avata System was developed, which evaluates real-time vascular perfusion in ambient light. This study aims to predict complications in autologous breast reconstruction using measures of relative intensity (RI) and relative area (RA).

METHODS

 Patients undergoing autologous breast reconstruction underwent intraoperative tissue perfusion assessment using the OnLume Avata System. Post-hoc image annotation was completed by labeling areas of the flap interpreted to be "Well Perfused," "Questionably Perfused," and "Under Perfused." RIs and RAs were calculated for the marked areas. Primary complications of interest were overall complication rate, fat and mastectomy skin flap necrosis, and surgical revision. Logistic regression was applied to determine the odds of developing a complication based on RI and RA for each image.

RESULTS

 A total of 25 patients (45 flaps) were included. In total, 17 patients (68%) developed at least one complication. Patients who developed any complication (p = 0.02) or underwent a surgical revision for complications (p = 0.02) had statistically lower RI of under-perfused portions of the flap. Patients with greater areas of under-perfused flap had a significantly higher risk of developing fat necrosis (odds ratio [OR]: 5.71, p = 0.03) and required a revision operation (OR: 1.10, p = 0.01).

CONCLUSION

 Image-based interpretation using the OnLume Avata System correlated with the risk of developing postoperative complications that standard fluorescence imaging systems may not appreciate. This information can benefit surgeons to improve perfusion assessment and intraoperative decision-making.

The Lipo-DIEP Flap Breast Reconstruction: A Valuable Innovation for Maximizing Abdominal Tissue Volume

Background

The deep inferior epigastric perforator (DIEP) flap is universally considered the gold standard technique for breast reconstruction (BR), though it cannot always be proposed to patients with insufficient donor-site volume. We explore the efficacy of autologous fat transfer (AFT) of the Holm abdomen zone IV in the retropectoral plane during DIEP flap reconstruction (lipo-DIEP flap), to enhance the volume provided by the abdominal donor site in patients with low body mass index (BMI).

Methods

We prospectively enrolled patients with BMI less than 25 kg/m2 and candidates for lipo-DIEP flap BR (group A) comparing them with a control group (group B) undergoing traditional DIEP flap BR with the same characteristics of the first group (BMI < 25 kg/m2). Patients belonging to group A underwent magnetic resonance imaging preoperatively and 6 months after the BR, evaluating the adipose tissue volume retained in the retropectoral space.

Results

A total of 40 breasts were included in the study. The 2 groups were homogeneous regarding the collected variables, except for mean delayed AFT sessions (0.25 versus 0.95; P= 0.00094). The average volume of retropectoral AFT was 116.25 mL (SD 31.36). Six months after the procedure, the mean retropectoral fat volume calculated through magnetic resonance imaging was 48.64 mL (SD 14.15), whereas the mean graft integration rate was 45.98% (range, 30.7%-64.2%).

Conclusions

The lipo-DIEP flap is a valuable technique for patients with insufficient donor-site volume. Immediate retropectoral fat grafting from the Holm zone IV has proven to be safe in terms of complications, reducing the need for further AFT sessions.

Clinical and Cost-Effectiveness of Intraoperative Flap Perfusion Assessment With Indocyanine Green Fluorescence Angiography in Breast and Head and Neck Reconstructions: A Systematic Review and Meta-Analysis

BACKGROUND

Indocyanine green fluorescence angiography (ICGFA) is gaining popularity for the assessment of reconstructive flap perfusion intraoperatively. This study analyses the literature with a focus on its clinical efficacy and cost-effectiveness across various plastic and reconstructive surgery procedures.

METHODS

A systematic review was conducted in accordance with PRISMA guidelines on published studies in English comparing ICGFA with standard clinical assessment for flap perfusion. Meta-analysis concerned perfusion-related complications and cost data.

RESULTS

Twenty-five studies met the inclusion criteria, of which two were randomized controlled trials (RCTs) and four were prospective cohort studies. Twenty-one studies were AHRQ Standard 'Good'; however, the overall level of evidence remains low. ICGFA was predominantly performed in breast surgeries (n = 3310) and head and neck reconstruction (n = 701) albeit with inconsistency in protocols and predominantly subjective interpretations (only five studies utilized objective thresholds). In breast surgery, meta-analysis demonstrated significant reductions in mastectomy skin flap necrosis (odds ratio (OR) 0.58, p < 0.0001), fat necrosis (OR 0.31, p < 0.001), infection (OR 0.66, p = 0.02), and re-operation (OR 0.40, p < 0.0001), but no significant decrease in total or partial flap loss (OR 0.78, p = 0.57/OR 0.87, p = 0.56, respectively) or increase in dehiscence (OR 1.55, p = 0.11). In head and neck surgery, ICGFA significantly decreased total flap loss (OR 0.47, p = 0.04), although not partial flap loss (OR 0.37, p = 0.13) and reoperation (OR 0.92, p = 0.73). Lower limb (n = 104) and abdominal wall (n = 95) reconstructive surgeries were much less studied with no significant ICGFA impact. Seven studies reported cost savings with flap surgeries and breast reconstructions, although study heterogeneity precluded meta-analysis.

CONCLUSIONS

ICGFA appears to be a useful, cost-effective tool to identify otherwise unsuspected hypoperfusion in breast and head and neck reconstruction. There is a clear need for standardization, however, to avoid bias. Further RCTs are necessary to solidify these promising clinical findings.

The Use of Pedicular Arteriovenous Fistula (PAVF) in Microvascular Reconstruction to Enhance Flow Across the Microvascular Anastomoses

BACKGROUND

Free flap success rates have improved dramatically over the past three decades, setting a high standard for microvascular reconstruction. However, rates of arterial or venous thrombosis, and subsequent failure, remain high in burn and trauma reconstruction when compared to autologous breast reconstruction and other elective flaps. To address the higher failure rate, we use a novel vascular approach. We create a pedicular arteriovenous fistula (PAVF), allowing the flow to be enhanced across the microvascular anastomoses.

METHODS

We performed a retrospective review of 13 consecutive patients with 14 free flaps who underwent PAVF creation by the first author, AO. All patients who required free tissue transfer for trauma and burn reconstruction were indicated for PAVF during this study period. The flaps in this study included ALT, fibula, parascapular, and partial latissimus. The perforator and pedicle for the flaps were dissected in the usual manner. Distal to the takeoff of the perforator to the flap, the pedicular artery and the larger of the accompanying veins were anastomosed to create the PAVF.

RESULTS

Patients were followed for a mean of 171 days Thrombosis was a rare complication in the group with one venous thrombosis (n = 1, 7.14%) and no arterial thrombosis. The most common complication was return to the operating room n = 4 (28.57%), two of which secondary to hematomas (14.29%), one wound dehiscence and one venous thrombosis. This latter patient eventually had partial flap loss.

DISCUSSION

We did not observe flap ischemia due to vascular steal, nor any venous congestion from pressurizing the venous outflow. As opposed to anticoagulation, flow enhancement aims to decrease the risk of thrombosis by reducing stasis. While further data is needed to compare the outcomes of venous enhanced flaps when compared to flaps treated prophylactically with anticoagulation, our initial data suggests that PAVF is a safe procedure and does not result in vascular steal or flap congestion.

The Utility of Indocyanine Green Angiography in Breast Reconstruction to Detect Mastectomy Skin Flap Necrosis and Free Flap Perfusion: An Umbrella Review

Two of the greatest challenges in breast reconstruction are mastectomy skin flap necrosis (MSFN) and autologous flap failure. This review summarizes current evidence regarding the usage of indocyanine green angiography (ICGA) in breast reconstruction, identifies knowledge gaps, and provides directions for future studies. An umbrella review was conducted to identify related syntheses in Embase, Ovid Medline, Scopus, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and the Clinical Trials databases. Data were extracted from systematic reviews (SRs) and meta-analyses (MAs) that discussed the use of ICGA in breast reconstruction. Sixteen syntheses were included (10 SRs and 6 MAs). Syntheses showed much evidence that ICGA usage typically reduces MSFN rates. However, it tends to overpredict necrosis and is best utilized in high-risk patients or those with an unclear clinical picture. ICGA is also useful in autologous breast reconstruction by reducing rates of breast fat necrosis (BFN), total flap loss, and reoperation. ICGA usage may also aid in perforator mapping and selection intraoperatively, with minimal complication risk. Most syntheses had moderate quality scores; however, they were small with significant heterogeneity in protocols and complication definitions. The use of ICGA in breast reconstruction is safe and useful in decreasing rates of MSFN, BFN, and reoperation after free flap reconstruction.

Tissue perfusion in DIEP flaps using Indocyanine Green Fluorescence Angiography, Hyperspectral imaging, and Thermal imaging

Flap necrosis continues to occur in skin free flap autologous breast reconstruction. Therefore, we investigated the benefits of indocyanine green angiography (ICGA) using quantitative parameters for the objective, perioperative evaluation of flap perfusion. In addition, we investigated the feasibility of hyperspectral (HSI) and thermal imaging (TI) for postoperative flap monitoring. A single-center, prospective observational study was performed on 15 patients who underwent deep inferior epigastric perforator (DIEP) flap breast reconstruction (n=21). DIEP-flap perfusion was evaluated using ICGA, HSI, and TI using a standardized imaging protocol. The ICGA perfusion curves and derived parameters, HSI extracted oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) values, and flap temperatures from TI were analyzed and correlated to the clinical outcomes. Post-hoc quantitative analysis of intraoperatively collected data of ICGA application accurately distinguished between adequately and insufficiently perfused DIEP flaps. ICG perfusion curves identified the lack of arterial inflow (n=2) and occlusion of the venous outflow (n=1). In addition, a postoperatively detected partial flap epidermolysis could have been predicted based on intraoperative quantitative ICGA data. During postoperative monitoring, HSI was used to identify impaired perfusion areas within the DIEP flap based on deoxyHb levels. The results of this study showed a limited added value of TI. Quantitative, post-hoc analysis of ICGA data produced objective and reproducible parameters that enabled the intraoperative detection of arterial and venous congested DIEP flaps. HSI appeared to be a promising technique for postoperative flap perfusion assessment. A diagnostic accuracy study is needed to investigate ICGA and HSI parameters in real-time and demonstrate their clinical benefit.

Perfusion area versus volume of the DIEP flap: A multivariable analysis of perforator and flap characteristics for estimation of perfusion area and volume

BACKGROUND

The extent of perfusion of a deep inferior epigastric artery perforator (DIEP) flap is a primary concern for surgeons. This study aimed to determine whether the flap area or volume can be estimated using perforator and flap characteristics.

METHODS

Intraoperative flap perfusion was assessed using indocyanine green angiography in patients who underwent DIEP flap breast reconstruction between November 2018 and February 2023. The area perfused by a single dominant perforator was delineated on the surface of the flap and measured using the ImageJ software. Multiple linear regression analysis was conducted to estimate the 'perfusion ratio,' defined as the perfused area divided by the total flap area. Potential predictor variables included flap size (cm2), flap thickness (mm), perforator diameter (mm), perforator rows (medial/lateral), vertical location of perforator (at or above/below the umbilicus), and perforator eccentricity (vertical distance from upper flap margin to perforator, cm).

RESULTS

In total, 101 patients were included in this analysis. The mean 'perfusion ratio' was 67.8% ± 11.5%, predicted by perforator diameter (p = 0.022) and vertical location below umbilicus (p < 0.001) with positive correlations and negatively correlated with flap thickness (p = 0.003) in the multivariable analysis. Both perfusion area and weight were predicted by perforator diameter, vertical location of perforator, flap size, and flap thickness (p < 0.001). The coefficient of determination (adjusted R2) for prediction of perfusion weight was higher than that for the perfusion area (75.5% vs. 69.4%).

CONCLUSIONS

Flap volume, rather than area, is determined by a perforator of a given diameter and location.

Alternatives to the Gold Standard: A Systematic Review of Profunda Artery Perforator and Lumbar Artery Perforator Flaps for Breast Reconstruction

INTRODUCTION

Breast reconstruction with the deep inferior epigastric perforator (DIEP) flap is the current gold-standard autologous option. The profunda artery perforator (PAP) and lumbar artery perforator (LAP) flaps have more recently been described as alternatives for patients who are not candidates for a DIEP flap. The aim of this study was to review the survival and complication rates of PAP and LAP flaps, using the DIEP flap as a benchmark.

METHODS

A literature search was conducted using PubMed, MEDLINE, Embase, BIOSIS, Web of Science, and Cochrane databases. Papers were screened by title and abstract, and full texts reviewed by three independent blinded reviewers. Quality was assessed using MINORS criteria.

RESULTS

Sixty-three studies were included, for a total of 745 PAP, 62 stacked PAP, 187 LAP, and 23,748 DIEP flap breast reconstructions. The PAP (98.3%) had comparable success rate to DIEP (98.4%), and the stacked PAP (88.7%) and LAP (92.5%) success rate was significantly lower (P < 0.0001). The PAP and LAP groups both had a low incidence of fat necrosis. However, the revision rate for the LAP group was 16.1% whereas the PAP group was 3.3%. Donor site wound dehiscence rate was 2.9 in the LAP group and 9.1% in the PAP group.

CONCLUSIONS

Profunda artery perforator and DIEP flaps demonstrate very high rates of overall survival. The LAP flap has a lower survival rate. This review highlights the survival and complication rates of these alternative flaps, which may help clinicians in guiding autologous reconstruction technique when a DIEP flap is unavailable.

The Impact of Technical Innovations and Donor-Site Mesh Repair on Autologous Abdominal-Based Breast Reconstruction-A Retrospective Analysis

Background: The aim of this study was to examine the potential benefit that may be achieved through the introduction of technical innovations and the incorporation of mesh for fascial donor site closure in uni- and bilateral autologous breast reconstruction with abdominal tissue. Methods: A retrospective single-center review of all breast reconstructions with a DIEP or MS-TRAM flap between January 2004 and December 2019 was performed. Donor and recipient site complications and operation times were evaluated before and after the implementation of coupler anastomoses, preoperative computed tomography angiography (CTA), indocyanine green (ICG) angiography, and the inclusion of mesh in donor site repair. Results: A total of 396 patients were included, accounting for 447 flaps. Operation time was significantly shorter in unilateral reconstructions after the implementation of CTA (p < 0.0001). ICG angiography significantly reduced the rates of partial flap loss (p = 0.02) and wound healing disorders (p = 0.02). For unilateral reconstructions, abdominal bulging or hernia was observed more often in MS1-TRAM flaps without synthetic mesh repair (p = 0.001), whereas conservatively treated seroma developed more frequently after mesh implantation (p = 0.03). Conclusions: Recent technological advancements developed over the past few decades have made a substantial impact on decreasing surgical duration and enhancing procedure safety.

Impact of Comorbidities on Sensory Return After Breast Reconstruction

PURPOSE

Breast anesthesia after mastectomy and reconstruction has been an ongoing concern with few improvements made in recent years. At present, there is a lack of studies evaluating the impact of comorbidities on sensation restoration. Identifying risk factors (RF) will be helpful with preoperative counseling.

METHODS

This was a prospective study on patients who underwent mastectomy and immediate implant-based or neurotized deep inferior epigastric perforator (DIEP) flap-based reconstruction. Neurosensory testing was performed at predefined time points using a pressure specified device. Patients were stratified based on reconstruction type and comorbidities, including obesity (≥30 kg/m2), age (>55 years), hypertension, alcohol use, and smoking status. Sensory comparisons among the comorbidity groups were conducted using unpaired 2-sample t tests.

RESULTS

A total of 239 patients were included in this study with 109 patients in the implant cohort and 131 patients in the DIEP cohort. One patient underwent bilateral reconstruction using both reconstructive modalities. Preoperatively, age older than 55 years was identified as an RF for reduced breast sensation in the implant cohort (difference in threshold, 10.7 g/mm2), whereas obesity was identified as an RF in the DIEP cohort (difference in threshold, 8 g/mm2). During the first 2 years postreconstruction, age older than 55 years and tobacco use history were found to be negatively correlated with breast sensation for both cohorts. With DIEP reconstruction specifically, obesity was identified as an additional RF during the early postoperative period. Of note, none of the comorbidities were found to be long-term RFs for reduced breast sensitivity. All breast sensation levels returned to comparable levels across all comorbidities by 4 years postreconstruction.

CONCLUSIONS

Currently, various comorbidities have been recognized as RFs for several postoperative complications including extended postoperative stay, necrosis, infection, and reoperation. However, our findings suggest that, although age, smoking history, and obesity showed transient associations with reduced breast sensation during the initial years postreconstruction, they play no role in the long-term potential of sensory nerve regeneration.

Deliberate Practice in DIEP Flap Breast Reconstruction: An Immediate and Sustained Decrease in Morbidity and Operative Time

BACKGROUND

Deep inferior epigastric perforator (DIEP) flaps are nuanced, multistep, complex procedures. Recent studies have hinted that operational flow can be a sensitive barometer for safety, efficiency, and overall outcomes. The authors critically assess the utility of implementing deliberate practice and process mapping as a research tool in the context of morbidity and operative time.

METHODS

Co-surgeons at a university hospital implemented deliberate practice and performed two prospective process analysis studies evaluating critical steps in DIEP flap reconstruction. During the 9-month period (June of 2018 to February of 2019), the flap harvest and microsurgery steps were assessed. During the 8-month period (January to August of 2020), the analysis was expanded to encompass the entire operation. To evaluate the immediate and sustained impact of process analysis, 375 bilateral DIEP flap patients were divided into eight consecutive 9-month intervals completed before, during, and after the two studies. Using risk-adjusted multivariate regressions, morbidity and operative time were compared between groups.

RESULTS

Time intervals completed before the first study had comparable morbidity and operative time. During the first study, there was an immediate 83.8% ( P < 0.001) decreased risk in morbidity. Operative time during the second study decreased by 2.19 hours ( P < 0.001). Morbidity and operative time continued to decrease until the end of data collection [62.1% decreased risk in morbidity ( P = 0.023) and decreased operative time of 2.22 hours ( P < 0.001)].

CONCLUSIONS

Deliberate practice and process analysis are powerful tools. Implementation of these tools can generate immediate and sustained decreases in morbidity and operative time for patients undergoing procedures such as DIEP flap breast reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Outcome analysis of free flap reconstruction for head and neck cancer with intraoperative indocyanine green angiography

BACKGROUND

Intraoperative indocyanine green (ICG) angiography is used in free flap surgery to evaluate the patency of vessel anastomosis. This study evaluated the outcomes of intraoperative ICG angiography in free flap surgery for head and neck cancer.

MATERIALS AND METHODS

This was a retrospective study of free flap reconstruction for head and neck cancer performed between 2015 and 2021. The outcomes analyzed were the total flap failure rate, re-exploration rate, and flap salvage rate. Differences in outcomes were compared in patients treated using intraoperative ICG angiography and those treated without.

RESULTS

Of the 520 free flap surgeries in the 486 enrolled patients, 259 cases underwent intraoperative ICG angiography. In this group, there were 10 (3.9%) cases of total flap failure. In the non-ICG group, there were 22 cases (8.4%). There were 35 (13.5%) cases requiring re-exploration in the ICG group and 40 (15.3%) in the non-ICG group. The difference was not statistically significant. The flap salvage rate was 75.8% (25/33) in the ICG group and 51.4% (18/35) in the non-ICG group, which was a significant difference.

CONCLUSION

We found that free flap surgery with intraoperative ICG angiography significantly decreased total flap failure rate and significantly increased salvage rate but did not significantly affect the re-exploration rate.

Quantification of Breast Volume According to age and BMI: A Three-Dimensional MRI Analysis of 400 Women

OBJECTIVE

Breast size alteration is the most common aesthetic surgical procedure worldwide. This study aimed to assess the correlation between breast volume and BMI or age.

MATERIALS AND METHODS

The analyses were conducted utilizing 400 patients selected by a retrospective review of the archives at our institution. Epidemiological data and medical history were assessed. Adjusting for the age and BMI of patient from previously described cohorts, we calculated mean breast volumes per side and differences from the upper and lower percentiles to the mean volumes.

RESULTS

The patients had a median BMI of 23.5 (range: 14.7-45.6) and a median age of 51 (range: 24-82). The average total breast volume increased strongly with BMI (r=0.834, p<0.01) and moderately with age (r=0.305, p<0.01). Within a BMI range of 18-24, breast volumes in the 8th and 18th percentile differ on average by about 50 ml. One BMI unit increase in women with breast sizes in the 10th percentile accounts for a breast volume difference of about 30 ml.

CONCLUSION

BMI strongly correlates with breast size. To achieve natural results, preoperative consultation and planning of aesthetic and reconstructive breast surgery must recognize BMI as a major determinant of average breast size.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Utility of the intraflap perfusion procedure for abdominal free flap in unilateral breast reconstruction

BACKGROUND

Heparin prophylaxis for venous thromboembolism can be used in microsurgery. If vein anastomosis is performed before the artery, heparin irrigation into the artery can be performed locally without systematic effect. This study aimed to introduce this "intraflap perfusion procedure" in autologous breast reconstruction.

METHODS

Among the 220 patients with unilateral breast cancer who had received the free abdominal flap, we retrospectively compared those that had undergone the intraflap perfusion procedure (n = 108) and those who did not (n = 112). A 10 mL injection of heparinized physiological saline solution (100 units/mL) was administered into the deep inferior epigastric artery. Intraflap perfusion was performed before, during, and after vein anastomosis, without the vessel clip of the vein. Artery anastomosis was performed without the use of a vein clamp. Further, vein anastomosis was performed tightly to prevent leakage from the vein anastomosis site during artery anastomosis.

RESULTS

The rates of superficial inferior epigastric vein (SIEV) superdrainage (18.5% vs. 42.0%, P < 0.001), and intraoperative flap congestion (0.9% vs. 8.0%, P = 0.01) were significantly lower in patients undergoing this procedure. There were no significant differences regarding other factors (age, BMI, laterality, comorbidities, and other operative details).

CONCLUSIONS

Intraflap perfusion prevented long-term stasis at the venous anastomosis site and capillary level. It could reduce flap congestion. SIEV superdrainage was performed to manage flap congestion, particularly in patients who did not undergo this procedure. Consequently, it can be inferred that this procedure reduces the rate of superdrainage.

Flap perfusion assessment with indocyanine green angiography in deep inferior epigastric perforator flap breast reconstruction: A systematic review and meta-analysis

BACKGROUND

Indocyanine green angiography (ICG-A) has been widely applied for intraoperative flap assessment in DIEP flap breast reconstruction. However, the beneficial effect of ICG-A in DIEP flap breast reconstruction is still uncertain and no standardized protocol is available. This study aims to analyze the clinical outcome and comprehensively review protocols of this field.

METHODS

A systematic review was conducted in MEDLINE, EMBASE, and Cochrane CENTRAL databases until September 15, 2022. Studies on the utility of intraoperative ICG-A in DIEP breast reconstruction were included. Data reporting reconstruction outcomes were extracted for pooled analysis.

RESULTS

A total of 22 studies were enrolled in the review, among five studies with 1021 patients included in the meta-analysis. The protocols of ICG-A assessment of DIEP flap varied among studies. According to the pooled results, the incidence of postoperative fat necrosis was 10.89% (50 of 459 patients) with ICG-A and 21.53% (121 of 562 patients) with clinical judgment. The risk for postoperative fat necrosis was significantly lower in patients with intraoperative ICG-A than without (RR 0.47 95% CI 0.29-0.78, p = .004, I2  = 51%). Reoperation occurred in 5 of 48 patients (10.42%) in the ICG-A group and in 21 of 64 patients (32.82%) in the control group summarized from reports in two studies. The risk for reoperation was lower in the ICG-A group than in the control group (RR 0.41 95% CI 0.18-0.93, p = .03, I2  = 0%). Other complications, including flap loss, seroma, hematoma, dehiscence, mastectomy skin necrosis, and infection, were comparable between the two groups. Heterogeneities among studies were acceptable. No significant influence of specific studies was identified in sensitivity analysis.

CONCLUSIONS

ICG-A is an accurate and reliable way to identify problematic perfusion of DIEP flaps during breast reconstruction. Protocols of ICG-A differed in current studies. Intraoperative ICG-A significantly decreases the rate of fat necrosis and reoperation in patients undergoing DIEP breast reconstruction. The synthesized results should be interpreted sensibly due to the sample size limitation. RCTs on the outcomes and high-quality studies for an optimized ICG-A protocol are still needed in the future.

Point-of-Care Tissue Oxygenation Assessment with SnapshotNIR for Alloplastic and Autologous Breast Reconstruction

In breast reconstruction, mastectomy and free flaps are susceptible to vascular compromise and tissue necrosis. The SnapshotNIR device (Kent Imaging, Calgary, AB, Canada) utilizes near-infrared spectroscopy to measure tissue oxygen saturation (StO₂) and hemoglobin concentration. Here, we report on the use of this device for StO₂ monitoring among patients receiving alloplastic or autologous breast reconstruction.

Methods

Patients receiving immediate alloplastic reconstruction after mastectomy or autologous reconstruction were enrolled. Preoperative, intraoperative, and postoperative images were taken of the flaps. StO₂ and hemoglobin were measured at the following locations: superior and inferior breast, free flap skin paddle (when applicable), and un-operated control skin. Linear mixed effects model for repeated measurements was used to model measurements to estimate the area effect difference across time, time effect difference across area, and pairwise comparisons between two areas at each time point.

Results

Thirty-two breasts underwent alloplastic reconstruction; 38 breasts underwent autologous reconstruction. No enrollees developed skin necrosis. StO₂ was highest after mastectomy and closure in alloplastic reconstructions. StO₂ was observed to decline at follow-up in autologous reconstructions. Mean preoperative StO₂ was highest in breasts that had previously undergone mastectomy and alloplastic reconstruction.

Conclusions

The SnapshotNIR device detected normal spatial and temporal differences in tissue oxygenation over the operative course of alloplastic and autologous breast reconstruction. A multi-institutional, prospective clinical trial is needed to determine the sensitivity and specificity of this device for detecting skin flap necrosis.

Use of intraoperative indocyanine green angiography for detection and prediction of congestion in pedicled island flaps

BACKGROUND

Pedicled island flaps, including pedicled propeller flaps and pedicled transposition flaps, are widely used especially for coverage of soft tissue defects in the extremities and the trunk. However, due to its mobility limitations, the inset of the pedicled flaps can be challenging at times, especially when rotation or pressure is applied to the pedicle. The aim of this report is to evaluate the feasibility of intraoperative indocyanine green (ICG) angiography for detection and prediction of intraoperative and postoperative flap congestion in pedicled island flaps.

PATIENTS AND METHODS

From June 2018 to November 2021, 26 consecutive patients who underwent immediate reconstruction using the pedicled island flap after sarcoma resection were enrolled. ICG angiography was performed after elevation of the flap, after temporary flap fixation, and after final flap inset. Sensitivity and specificity of the last ICG angiography were calculated.

RESULTS

In 22 cases where the last ICG angiography highlighting showed a satisfactory flap, the flap survived completely. In four cases where the flap was not highlighted by the final ICG angiography but did not show other clinical signs of congestion, all flaps underwent total loss due to congestion. The sensitivity and specificity of the final ICG angiography for predicting postoperative flap congestion were both 100%.

CONCLUSION

ICG angiography can accurately predict postoperative congestion of the pedicled island flap, with extremely high sensitivity and specificity. When the flap is insufficiently highlighted after final flap inset, other measures should be considered.

Indocyanine green (ICG) fluorescence guide for the use and indications in general surgery: recommendations based on the descriptive review of the literature and the analysis of experience

Indocyanine Green is a fluorescent substance visible in near-infrared light. It is useful for the identification of anatomical structures (biliary tract, ureters, parathyroid, thoracic duct), the tissues vascularization (anastomosis in colorectal, esophageal, gastric, bariatric surgery, for plasties and flaps in abdominal wall surgery, liver resection, in strangulated hernias and in intestinal ischemia), for tumor identification (liver, pancreas, adrenal glands, implants of peritoneal carcinomatosis, retroperitoneal tumors and lymphomas) and sentinel node identification and lymphatic mapping in malignant tumors (stomach, breast, colon, rectum, esophagus and skin cancer). The evidence is very encouraging, although standardization of its use and randomized studies with higher number of patients are required to obtain definitive conclusions on its use in general surgery. The aim of this literature review is to provide a guide for the use of ICG fluorescence in general surgery procedures.

The correlation of flap blood glucose with fat necrosis of free abdominal flap for unilateral breast reconstruction

BACKGROUND

Flap blood glucose (FBG) measurement is proposed as a monitoring technique. A cause of long-lasting fever could be derived from fat necrosis. If the findings of low FBG correlated with fat necrosis, it could predict the poor cosmetic result and a source of fever. However, this correlation remained unsolved. The purpose of this study was to clarify this correlation in breast reconstruction.

METHODS

In the 180 unilateral breast cancer patients (mean age = 49.8 years) performed free abdominal flap, we retrospectively compared the group where fat necrosis occurred with the group where it did not occur (45 patients with fat necrosis vs. 135 patients without). We compared the average of FBG in each postoperative day.

RESULTS

The average FBG was significantly lower in patients with fat necrosis in the second postoperative day (115.3 ± 27.3 vs. 126.3 ± 13.7 mg/dl, p = .026) and the third postoperative day (111.1 ± 22.1 vs. 118.8 ± 13.8 mg/dl, p = .036). Mean BMI and inserted total flap weight were significantly higher in patients with the fat necrosis group (24.8 vs. 22.9 kg/m² , p = .005) (617 vs. 478 g, p = .006). The multivariate analysis revealed early FBG (OR = 0.96, p = .0002) and laterality (right side) (OR = 0.46, p = .043) were independently significant predictors. There were no significant between-group differences regarding other factors (age, systemic blood glucose, comorbidities and operative details).

CONCLUSIONS

The possibility of fat necrosis was high for patients with low FBG in the early postoperative day.

[Increasing Safety in Microsurgical Breast Reconstruction - Technique and Technology]

Microsurgical reconstruction has established itself as a standard procedure in breast reconstruction as it permits creation of a natural and aesthetically appealing breast mound, even after modified radical mastectomy and radiation. In the past few decades numerous new free flap donor-sites have been described that permit an individualized approach to reconstruction, thus, resulting in a high level of patient satisfaction. Paralleling these technical innovations, the focus of microsurgical breast reconstruction has shifted from mere "flap success" to "aesthetic outcome", while also taking into account the respective donor-site morbidity. Here, the authors discuss contemporary developments in the field with a particular focus on surgical techniques and technologies that contribute to increasing the safety of microsurgical breast reconstruction.

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 Blood Flow Analysis of DIEP vs. ms-TRAM Flap Breast Reconstruction Combining Transit-Time Flowmetry and Microvascular Indocyanine Green Angiography

Background: Vascular patency is the key element for high flap survival rates. The purpose of this study was to assess and compare the blood flow characteristics of deep inferior epigastric perforator (DIEP) and muscle-sparing transverse rectus abdominis musculocutaneous (ms-TRAM) flaps for autologous breast reconstruction. Methods: This prospective clinical study combined Transit-Time Flowmetry and microvascular Indocyanine Green Angiography for the measurement of blood flow volume, vascular resistance, and intrinsic transit time. Results: Twenty female patients (mean age, 52 years) received 24 free flaps (14 DIEP and 10 ms-TRAM flaps). The mean arterial blood flow of the flap in situ was 7.2 ± 1.9 mL/min in DIEP flaps and 11.5 ± 4.8 mL/min in ms-TRAM flaps (p < 0.05). After anastomosis, the mean arterial blood flow was 9.7 ± 5.6 mL/min in DIEP flaps and 13.5 ± 4.2 mL/min in ms-TRAM flaps (p = 0.07). The arterial vascular resistance of DIEP flaps was significantly higher than that of ms-TRAM flaps. The intrinsic transit time of DIEP flaps was 52 ± 18 s, and that of ms-TRAM flaps was 33 ± 11 s (p < 0.05). The flap survival rate was 100%. One DIEP flap with the highest intrinsic transit time (77 s) required surgical revision due to arterial thrombosis. Conclusion: In this study, we established the blood flow characteristics of free DIEP and ms-TRAM flaps showing different blood flow rates, vascular resistances, and intrinsic transit times. These standard values will help to determine the predictive values for vascular compromise, hence improving the safety of autologous breast reconstruction procedures.

Assessment of deep inferior epigastric perforator flap perfusion with near-infrared fluorescence: A pilot study and description of a standardized working protocol

Fat necrosis (FN) is a common complication after autologous breast reconstruction (ABR) using a free flap, which can influence reconstruction outcome and patient satisfaction. Intraoperative near-infrared fluorescence imaging using indocyanine green (ICG) permits the visualization of flap perfusion. The aim of this study was to assess the effect of near-infrared fluorescence on FN incidence in patients undergoing an ABR with a deep inferior epigastric perforator flap (DIEP) and to propose a standard working protocol for this technique. In this prospective study, patients undergoing one-sided ABR with a DIEP were included. The standard DIEP procedure was complemented with near-infrared fluorescence imaging using the fluorescent tracer ICG to evaluate flap perfusion. This cohort was compared to a retrospective cohort of DIEP procedures without near-infrared fluorescence imaging. Patients and surgery characteristics, as well as postoperative complications, were registered and compared. In both cohorts, 24 patients were included. No significant differences were present between patients and surgery characteristics, including no difference in duration of surgery. In the prospective and retrospective group, the incidence of FN was 4.2% and 33%, respectively (p-value = 0.023). Moreover, microsurgeons were positive about using near-infrared fluorescence as it either provided additional information about perfusion or confirmed the clinical assessment. Our pilot study showed a significant decrease of FN in patients undergoing an ABR with a DIEP when near-infrared fluorescence imaging was used to assess flap perfusion. This study provides a standardized working protocol for near-infrared fluorescence imaging. In the future, large multicenter studies should focus on the quantification of near-infrared fluorescence imaging.

Bilateral Outpatient Breast Reconstruction with Stacked DIEP and Vertical PAP Flaps

Background:

Stacking free flaps for breast reconstruction is far from novel, even in the case of a deep inferior epigastric perforator (DIEP) plus profunda artery perforator (PAP) configuration, where the latter is always described in the traditional transverse configuration. We present a series of consecutive patients undergoing bilateral breast reconstruction with stacked DIEP and vertical PAP flaps.

Methods:

Patients with inadequate abdominal donor tissue were offered the possibility of a stacking breast reconstruction. The DIEP flap was harvested via microfascial incisions, whereas the vertical PAP flap was harvested in the lithotomy position, following the course of the gracilis muscle.

Results:

In total, 28 consecutive patients with a mean BMI of 24.9 underwent bilateral breast reconstruction with stacked DIEP and vertical PAP flaps. The internal mammary artery and vein were used as recipient vessels in all 56 stacked flaps. Fifty-three PAP flaps were anastomosed to the distal portion of the (primary) DIEP flaps utilizing a sequential flap anastomosis technique, and one DIEP flap was anastomosed to the distal portion of the (primary) PAP flap. Hospitalization for the initial eight patients averaged 35 hours, whereas the following 20 patients were discharged within 23 hours. There were no postoperative takebacks or vascular complications.

Conclusions:

Stacked DIEP/PAP flaps offer an excellent option for patients who require more volume than available from DIEP flaps alone. When compared with transverse PAP flaps, the vertical PAP offers excellent variability of volume and ease of shaping to allow for excellent results, while minimizing donor site tension in the seated position and preserving the gluteal fold.

Efficient DIEP Flap: Bilateral Breast Reconstruction in Less Than Four Hours

INTRODUCTION

The DIEP flap is considered the gold standard in autologous breast reconstruction. Despite the benefit of a lifelong natural reconstruction, some argue that the potential drawbacks, specifically operative time and recovery, are significant. We recently focused specifically on process analysis in our DIEP flap practice and present a comprehensive analysis in efficient DIEP flap breast reconstructions.

METHODS

Fifty consecutive bilateral DIEP flaps were prospectively tracked (100 flaps). The procedure was divided into segments (recipient site preparation, DIEP flap dissection/harvest, microsurgery, breast shaping, and abdominal closure). All individual step times were recorded for each team member. Relevant patient characteristics, intraoperative details and postoperative outcomes were recorded.

RESULTS

Average surgical time was 3 hours and 58 minutes (the fastest time recorded was 2 h and 14 min). There were no immediate postoperative complications. The anastomotic revision rate was 6%. Four surgeons contributed 34.7% of the time, three surgeons 32.2% of the time, two surgeons 23.6% of the time, and one surgeon 4.8% of total time. In procedures under 4 hours, four surgeons contributed simultaneously 36.7% of the time compared to 21.8% in the longer procedures (P = 0.004). Four surgeons contributed 45.4% of the time (P = 0.01) in the sub-three-hour bilateral DIEP flap procedures.

CONCLUSIONS

Efficient DIEP flap breast reconstruction can be accomplished with a well-trained and coordinated team approach involving like-minded surgeons with extensive experience working together. The synergistic map shows constant movement with utilization of hidden time, without sacrificing education, outcomes, or innovation.

Innovations for the future of breast surgery

BACKGROUND

Future innovations in science and technology with an impact on multimodal breast cancer management from a surgical perspective are discussed in this narrative review. The work was undertaken in response to the Commission on the Future of Surgery project initiated by the Royal College of Surgeons of England.

METHODS

Expert opinion was sought around themes of surgical de-escalation, reduction in treatment morbidities, and improving the accuracy of breast-conserving surgery in terms of margin status. There was emphasis on how the primacy of surgical excision in an era of oncoplastic and reconstructive surgery is increasingly being challenged, with more effective systemic therapies that target residual disease burden, and permit response-adapted approaches to both breast and axillary surgery.

RESULTS

Technologies for intraoperative margin assessment can potentially half re-excision rates after breast-conserving surgery, and sentinel lymph node biopsy will become a therapeutic procedure for many patients with node-positive disease treated either with surgery or chemotherapy as the primary modality. Genomic profiling of tumours can aid in the selection of patients for neoadjuvant and adjuvant therapies as well as prevention strategies. Molecular subtypes are predictive of response to induction therapies and reductive approaches to surgery in the breast or axilla.

CONCLUSION

Treatments are increasingly being tailored and based on improved understanding of tumour biology and relevant biomarkers to determine absolute benefit and permit delivery of cost-effective healthcare. Patient involvement is crucial for breast cancer studies to ensure relevance and outcome measures that are objective, meaningful, and patient-centred.

Use of Indocyanine Green Angiography decreases the risk of complications in autologous- and implant-based breast reconstruction: A systematic review and meta-analysis

INTRODUCTION

Indocyanine Green Angiography (ICG-A) is an imaging technique used to visualize tissue perfusion in real time. The aim of this systematic review and meta-analysis is to evaluate all published papers on breast reconstruction using ICG-A, which provides information on complication rates and to investigate whether the use of this peroperative method decreases the risk of complications.

MATERIALS AND METHODS

MEDLINE/PubMed, EMBASE, Cochrane, and UpToDate were searched using relevant terms. The literature was assessed using the PRISMA guidelines. Inclusion criteria were: original articles written in English assessing ICG-angiography in breast reconstruction. The individual studies were evaluated according to Cochrane guidelines.

RESULTS

The search yielded 243 papers on ICG-A and breast reconstruction. Twenty-six of these were included for analysis. The risk of overall major complications ([OR] = 0.53, 95% confidence interval (CI) = 0.43-0.66, p = 0.00001) and overall loss of reconstruction ([OR] = 0.58, 95% CI = 0.37-0.92, and p = 0.020) was significantly lower when peroperative ICG-A was used. When using ICG-A to evaluate mastectomy flaps, a statistically lower risk of major complications ([OR] = 0.56 and p = 0.0001) and the loss of reconstruction was found ([OR] = 0.46, p = 0.006). ICG-A used in autologous breast reconstruction significantly reduced the risk of minor ([OR] = 0.62 and p = 0.001) and major complications ([OR] = 0.53 and p = 0.0028).

CONCLUSIONS

This is the first systematic review to analyze the use of ICG-A on both mastectomy flaps and autologous reconstruction. The results obtained in the current study indicate that the use of ICG-A in breast reconstructive procedures reduces the complications as well as the loss of reconstruction.

Abdominal subcutaneous fat thickness as a substitute for BMI in predicting complications in abdominally-based autologous breast reconstruction

INTRODUCTION

Patient selection for autologous tissue transfer for postmastectomy breast reconstruction often utilizes body mass index (BMI) to risk stratify patients, though it only estimates fat content and does not address fat distribution. This study aims to identify a measurement of abdominal subcutaneous fat thickness (ASFT) from preoperative computed tomography (CT) angiography imaging to better predict complications.

METHODS

A retrospective review of patients who underwent an abdominal microvascular free flap breast reconstruction was performed. The average of the bilateral distances from the lateral border of the rectus abdominus to the most proximal point of the dermis at the L4-L5 space was measured on preoperative imaging to estimate ASFT. This measurement was compared to BMI in regards to correlation with any complication, major or minor complications, and donor or recipient site complications. Statistical analysis utilized point-biserial correlations and multivariable logistic regression analyses.

RESULTS

Three hundred and nine cases comprising a total of 496 breast reconstructions were identified. BMI did not correlate with any of the grouped complications, while ASFT correlated with occurrence of any complication (p = .003), minor complications (p = .001), and recipient site complications (p = .001). Further analysis revealed ASFT is specifically correlated with fat necrosis (p = .005). In independent multivariable regression models, both BMI (p = .011) and ASFT (p = .001) were significant predictors of fat necrosis. The ASFT model had a BIC of 335.42 compared to the BMI model with a value of 340.89, with smaller numbers representing more predictive models.

CONCLUSION

Estimation of ASFT is easily performed and is a significantly better predictor of flap fat necrosis than BMI.