Indocyanine green-based fluorescent angiography in breast reconstruction

Prospective Clinical Trial for Predicting Mastectomy Skin Flap Necrosis with Indocyanine Green Angiography in Implant-Based Prepectoral Breast Reconstruction

BACKGROUND

Indocyanine green angiography (ICG-A) is a useful tool for evaluating mastectomy skin flap (MSF) perfusion during breast reconstruction. However, a standardized protocol for interpreting and applying MSF perfusion after mastectomy has not been established yet. The purpose of this study is to establish criteria for assessing MSF perfusion in immediate implant-based prepectoral breast reconstruction while correlating ICG-A findings with postoperative outcomes METHODS: This prospective observational study was conducted at a single institution and involved patients with breast cancer who underwent mastectomy and immediate implant-based prepectoral breast reconstruction between August 2021 and August 2023. The terms "hypoperfused flap" and "hypoperfused area" were defined according to ICG-A perfusion. MSF exhibited < 30% perfusion, excluding the nipple and the corresponding region, respectively. Data on the hypoperfused flap, hypoperfused area, and MSF necrosis were collected.

RESULTS

Fifty-three breast cases were analyzed. Eight patients developed MSF necrosis (15.1%, 8/53). Of these, two patients underwent surgical debridement and revision within 3 months (3.8%, 2/53). There were nine cases of a hypoperfused flap, eight of which developed MSF necrosis. The hypoperfused flap was a significant predictor of the occurrence of MSF necrosis (p < 0.001). There was a tendency for increased full-thickness necrosis with a wider hypoperfused area.

CONCLUSIONS

The hypoperfused flap enabled the prediction of MSF necrosis with high sensitivity, specificity, positive predictive value, and negative predictive value. Considering the presumed correlation between the extent of the hypoperfused area and the need for revision surgery, caution should be exercised when making intraoperative decisions regarding the reconstruction method.

LEVEL OF EVIDENCE III

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 .

Indocyanine green angiography guidance for vascular preservation in skin and nipple sparing mastectomy

PURPOSE

The skin and/or nipple-sparing approach has become an oncologically sound and desirable choice for women choosing mastectomy. Indocyanine green (ICG) perfusion imaging has been shown to reduce ischemic complications in mastectomy skin flaps. Immediate reconstruction requires a well-vascularized skin flap capable of tolerating full expansion. Identification of the perforating subcutaneous vessels to the skin envelope may allow for better and more consistent blood vessel preservation and flap perfusion.

METHODS

The authors conducted an institutional review board-approved prospective study with 41 patients to assess the feasibility of using ICG perfusion imaging to visualize, cutaneously map, and preserve the vessels that supply the skin flap and nipple-areolar complex. For each patient, the number of vessels initially mapped, the number of vessels preserved, the extent to which each vessel was preserved, and the proportion of the flap with adequate perfusion (as defined by the SPY-Q > 20% threshold) was recorded and analyzed.

RESULTS

Vessels were able to be identified and marked in a high majority of patients (90%). There was a moderate linear relationship between the number of vessels marked and the number preserved. Successful mapping of vessels was associated with lower rates of wound breakdown (p = 0.036). Mapping and preserving at least one vessel led to excellent flap perfusion (> 90%). No increase in complications was observed from utilizing ICG angiography preoperatively.

CONCLUSION

This prospective study using preoperative ICG perfusion mapping demonstrated safety, feasibility, and good prognostic outcomes.

LEVEL OF EVIDENCE

III.

Superomedial Pedicle Technique and Management of Circulation Problems in Gigantomastia : Treatment of Gigantomastia

Breast reduction surgeries encompass a wide range of methods that are continuously evolving to discover more reliable and satisfactory techniques. This presentation aims to address the research gap by sharing outcomes and experiences using the superomedial pedicle in gigantomastia, as well as the implemented protocol for managing nipple-areola complex (NAC) ischemia. The Wise pattern and superomedial pedicle reduction mammaplasty method were utilized in treating 19 patients (38 breasts). The average age of the patients was 41.47 years, with a basal mass index (BMI) of 33.27 kg/m2. The mean sternal notch to nipple (SN-N) length for the entire population was found to be 40.97 cm. On both sides, this length was statistically similar at 41.11 cm on the right side and 40.84 cm on the left side. The average weight of resected tissue from all patients was calculated to be 1793.42 g, with slightly higher weight on the right side at 1800 g compared to the left side's weight of 1786.84 g. Postoperative NAC ischemia occurred in three patients, one bilateral case, and two unilateral cases. The study revealed that in both the groups with and without NAC ischemia, the average values were as follows: age, which ranged from 45.33 to 40.75 years; BMI, ranging from 35.01 kg/m2 to 32.95 kg/m2; SN-N distance, which varied from 40 cm to 41.09 cm; and excision material weights, ranging from 1650 g to 1810.29 g. The p-value in the comparisons was found to be greater than 0.05. These results indicate that age, BMI, SN-N distance, and excision material weight did not have an impact on NAC vascularity issues. All NACs were successfully saved through a protocol involving hyperbaric oxygen therapy (HOT) and vacuum-assisted therapy (VAT). The study suggests that utilizing a superomedial flap is a viable option for treating gigantomastia and highlights the effectiveness of their outlined protocol in managing postoperative complications. While acknowledging the need for comparative studies, the study proposes incorporating HOT and VAT into protocols aimed at saving NACs.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 .

2024 TSOC/TSPS Joint Consensus: Strategies for Advanced Vascular Wound Management in Arterial and Venous Diseases

The Taiwan Society of Cardiology (TSOC) and Taiwan Society of Plastic Surgery (TSPS) have collaborated to develop a joint consensus for the management of patients with advanced vascular wounds. The taskforce comprises experts including preventive cardiologists, interventionists, and cardiovascular and plastic surgeons. The consensus focuses on addressing the challenges in diagnosing, treating, and managing complex wounds; incorporates the perfusion evaluation and the advanced vascular wound care team; and highlights the importance of cross-disciplinary teamwork. The aim of this joint consensus is to manage patients with advanced vascular wounds and encourage the adoption of these guidelines by healthcare professionals to improve patient care and outcomes. The guidelines encompass a range of topics, including the definition of advanced vascular wounds, increased awareness, team structure, epidemiology, clinical presentation, medical treatment, endovascular intervention, vascular surgery, infection control, advanced wound management, and evaluation of treatment results. It also outlines a detailed protocol for assessing patients with lower leg wounds, provides guidance on consultation and referral processes, and offers recommendations for various wound care devices, dressings, and products. The 2024 TSOC/TSPS consensus for the management of patients with advanced vascular wounds serves as a catalyst for international collaboration, promoting knowledge exchange and facilitating advancements in the field of advanced vascular wound management. By providing a comprehensive and evidence-based approach, this consensus aims to contribute to improved patient care and outcomes globally.

Lymphoedema surgery in Australia: a narrative review

Background and Objective

Lymphoedema is a chronic condition that affects millions of people worldwide. It is often caused by the damage or removal of lymph nodes during cancer treatment. One of the most effective management options for lymphoedema is surgery, which can reduce swelling and potentially improve lymphatic drainage. Throughout history, Australia has been at the forefront of research and development in this field. In this review, we aim to examine the contributions of Australian research to lymphoedema surgery.

Methods

We conducted a search in the PubMed and Embase databases to identify Australian research relating to lymphoedema surgery from inception to the present day. Studies that met the inclusion criteria were reviewed and analysed, and the results were presented.

Key Content and Findings

After reviewing the literature, it was apparent that the field of lymphoedema surgery owes much to the contributions of Australian research. Early work from famous Australian surgeons such as Bernard O'Brien and Geoffrey Ian Taylor laid the bedrock for modern surgical techniques. Furthermore, more recently, Australia has seen a resurgence of clinical research contributing to the international evidence for lymphoedema surgery.

Conclusions

Australia has made significant contributions to the field of lymphoedema surgery, particularly in the development of modern microsurgical techniques such as lymphovenous anastomosis or vascularised lymph node transfer. These contributions have led to improved patient outcomes and quality of life. Going forward, Australia will hopefully continue to be a leader in research and innovation in this field.

Mastectomy Skin Flap Stability Prediction Using Indocyanine Green Angiography: A Randomized Prospective Trial

BACKGROUND

The first step in successful breast reconstruction is obtaining a stable skin flap. Indocyanine green (ICG) angiography has recently been studied for its value and usefulness in predicting the stability of skin flaps; however, relevant prospective studies of its clinical efficacy are limited.

OBJECTIVES

The aim of this study was to prospectively investigate the clinical impact on breast reconstruction outcomes of the intraoperative use of ICG angiography.

METHODS

Between March and December 2021, 64 patients who underwent immediate breast reconstruction at the authors' institution were prospectively enrolled. They were classified into an experimental group (n = 39; undergoing ICG angiography) and a control group (n = 25; undergoing gross inspection alone). In the absence of viable skin, debridement was performed at the surgeon's discretion. Skin complications were categorized as skin necrosis (the transition of the skin flap to full-thickness necrosis) or skin erosion (a skin flap that did not deteriorate or become necrotic but lacked intactness).

RESULTS

The 2 groups were matched in terms of basic demographic characteristics and incision line necrosis ratio (P = .354). However, intraoperative debridement was significantly more frequent in the experimental group (51.3% vs 48.0%, P = .006). The authors additionally classified skin flap necrosis into partial- and full-thickness necrosis, with a higher predominance of partial-thickness necrosis in the experimental vs control group (82.8% vs 55.6%; P = .043).

CONCLUSIONS

Intraoperative ICG angiography does not directly minimize skin erosion or necrosis. However, compared to gross examination alone, it enables surgeons to perform a more active debridement during surgery, thereby contributing to a lower incidence of advanced skin necrosis. In breast reconstruction, ICG angiography may be useful for assessing the viability of the postmastectomy skin flap and could contribute to successful reconstruction.

LEVEL OF EVIDENCE

4.

Contralateral internal mammary artery perforator flap for large inner chest wall defect repair and immediate breast reconstruction after excision of large malignant inner breast tumors

OBJECTIVES

Large breast tumor resection can cause chest wall defects that are difficult to close. A combination of oncoplastic techniques is required to repair chest wall defects and immediately reconstruct the breast. In this report, we present the use of the contralateral internal mammary artery perforator (IMAP) flap to repair large chest wall defects and perform breast reconstruction for a series of patients.

METHODS

Between July 2013 and June 2020, 10 patients and 4 patients underwent chest wall defect repair and breast reconstruction, respectively, with contralateral IMAP flaps. The average body mass index was 26.9 kg/m2 (range: 21.5-33.7 kg/m2 ). Tumor sizes varied from 2.5 × 1.5 × 0.8 to 9.5 × 6.0 × 4.0 cm3 . Defect sizes ranged from 16 × 10 to 8 × 4 cm2 . All patients underwent multiple imaging examinations to exclude abnormalities. Primary outcomes included complete tumor resection and flap survival. Secondary outcomes included the BREAST-Q results and bilateral breast symmetry measurements.

RESULTS

All flaps exhibited good postoperative survival and were between 20 × 12 and 10 × 5 cm2 . Two patients experienced minor complications that did not influence outcomes. No obvious donor site complications were observed. The BREAST-Q results indicated favorable reconstructive efficacy, with "satisfaction with breasts," "physical well-being (chest)," and "satisfaction with the outcome" scores of 77.8 (range: 58-87), 83.2 (range: 77-89), and 80.1 (range: 70-88), respectively. No signs of tumor recurrence were observed during a median follow-up period of 53.5 months (range: 6-83 months). However, poor postoperative bilateral breast symmetry was observed (vertical extent: 0.63 [range: 0.36-0.88]; horizontal extent: 0.64 [range: 0.41-0.80]).

CONCLUSIONS

IMAP flaps are reliable options for chest wall defect repair and breast reconstruction for selected patients with locally advanced breast cancer and inner breast tumors. Despite poor postoperative bilateral breast symmetry, most patients reported excellent outcomes.

Novel Dual Tracer Indocyanine Green and Radioisotope Versus Gold Standard Sentinel Lymph Node Biopsy in Breast Cancer: The GREENORBLUE Trial

BACKGROUND

The methods for sentinel lymph node (SLN) biopsy in breast cancer have been variable in type and number of tracers. Some units have abandoned the use of blue dye (BD) due to adverse reactions. Fluorescence-guided biopsy with indocyanine green (ICG) is a relatively novel technique. This study compared the clinical efficacy and costs between novel dual tracer ICG and radioisotope (ICG-RI) with "gold standard" BD and radioisotope (BD-RI).

METHODS

Single-surgeon study of 150 prospective patients with early breast cancer undergoing SLN biopsy (2021-2022) using ICG-RI compared with a retrospective cohort of 150 consecutive previous patients using BD-RI. Number of SLNs identified, rate of failed mapping, identification of metastatic SLNs, and adverse reactions were compared between techniques. Cost-minimisation analysis performed by using Medicare item numbers and micro-costing analysis.

RESULTS

Total number of SLNs identified with ICG-RI and BD-RI was 351 and 315, respectively. Mean number of SLNs identified with ICG-RI and BD-RI was 2.3 (standard deviation [SD] 1.4) and 2.1 (SD 1.1), respectively (p = 0.156). There were no cases of failed mapping with either dual technique. Metastatic SLNs were identified in 38 (25.3%) ICG-RI patients compared with 30 (20%) BD-RI patients (p = 0.641). There were no adverse reactions to ICG, whereas four cases of skin tattooing and anaphylaxis were associated with BD (p = 0.131). ICG-RI cost an additional AU$197.38 per case in addition to the initial cost for the imaging system.

CLINICAL TRIAL REGISTRATION

 ACTRN12621001033831.

CONCLUSIONS

Novel tracer combination, ICG-RI, provided an effective and safe alternative to "gold standard" dual tracer. The caveat was the significantly greater costs associated with ICG.

Educational Review: Intraoperative Parathyroid Fluorescence Detection Technology in Thyroid and Parathyroid Surgery

BACKGROUND

Accurate parathyroid gland (PG) identification is a critical yet challenging component of cervical endocrine procedures. PGs possess strong near-infrared autofluorescence (NIRAF) compared with other tissues in the neck. This property has been harnessed by image- and probe-based near-infrared fluorescence detection systems, which have gained increasing popularity in clinical use for their ability to accurately aid in PG identification in a rapid, noninvasive, and cost-effective manner. All NIRAF technologies, however, cannot differentiate viable from devascularized PGs without the use of contrast enhancement. Here, we aim to provide an overview of the rapid evolution of these technologies and update the surgery community on the most recent advancements in the field.

METHODS

A PubMed literature review was performed using the key terms "parathyroid," "near-infrared," and "fluorescence." Recommendations regarding the use of these technologies in clinical practice were developed on the basis of the reviewed literature and in conjunction with expert surgeons' opinions.

RESULTS

The use of near-infrared fluorescence detection can be broadly categorized as (1) using parathyroid NIRAF to identify both healthy and diseased PGs, and (2) using contrast-enhanced (i.e., indocyanine green) near-infrared fluorescence to evaluate PG perfusion and viability. Each of these approaches possess unique advantages and disadvantages, and clinical trials are ongoing to better define their utility.

CONCLUSIONS

Near-infrared fluorescence detection offers the opportunity to improve our collective ability to identify and preserve PGs intraoperatively. While additional work is needed to propel this technology further, we hope this review will be valuable to the practicing surgeon.

Influence of vertical location and spacing of perforators on perfusion in deep inferior epigastric artery perforator flap breast reconstruction: quantitative analysis using indocyanine green angiography

Background

This study quantitatively assessed perfusion of the deep inferior epigastric artery perforator (DIEP) flap according to vertical location and vertical spacing of perforators during DIEP flap breast reconstruction.

Methods

In 67 patients who underwent unilateral DIEP flap breast reconstruction between November 2018 and August 2021, flap perfusion was intraoperatively assessed using indocyanine green angiography. Perforators located at or above the umbilicus were defined as vertical zone 1 perforators and those below the umbilicus as vertical zone 2 perforators. Perfusion assessment was conducted in two stages: at stage 1, perfusion solely by single dominant perforators was assessed. At stage 2, the perfusion increment effected by adding a single additional perforator was assessed. Perfused area proportions were compared between patients with dominant perforators in zone 1 versus zone 2. The effect of adding an additional perforator to another vertical zone ("vertical spacing") was also assessed.

Results

The perfused proportion was significantly higher among vertical zone 2 perforators compared with zone 1 perforators in the evaluation of single dominant perforators (70% vs. 56%; P<0.001). In the evaluation of incremented perfusion by single additional perforators, the perfused proportion was significantly higher in the vertical-spacing group compared to the no-vertical-spacing group (17% vs. 12%; P=0.004). Fat necrosis developed in 4.5 percent of the patients over at least 6 months of follow-up.

Conclusions

DIEP flap perfusion can be affected by the vertical location of perforators, and flap perfusion can be augmented effectively by vertical spacing of perforators.

Preventing Soft Tissue Complications in Secondary Aesthetic Breast Surgery Using Indocyanin Green Angiography

BACKGROUND

Secondary cosmetic breast surgery after primary augmentation with implant can be associated with an increased risk of adverse events. Partial/complete nipple areolar complex (NAC) necrosis is particularly feared. In this preliminary study, the authors propose the use of Indocyanine Green (ICG) angiography in order to assess the blood supply of breast tissue after implant removal.

OBJECTIVES

The main objective is to prevent skin and gland necrosis in revision breast surgery.

METHODS

We performed a retrospective comparative analysis of 33 patients undergoing secondary breast surgery between 2018 and 2021 by a single surgeon (M.S.). Breast tissue perfusion was assessed in 16 patients by intraoperative ICG-angiography at the end of implant removal and possible capsulectomy. Non-stained/non-fluorescent areas were judged to be low perfusion areas and were excised with short scar mastopexy.

RESULTS

In the ICG-angiography group, 7 patients (44%) showed an area of poor perfusion along the inferior pole, all of these patients underwent subglandular breast augmentation. Resection of the poor perfusion areas allowed an uneventful postoperative course. In the non ICG-angiography group (17 patients), 5 patients experienced vertical scar dehiscence/necrosis. We found a statistically significant association between non-ICG angiography group and vertical scar dehiscence/necrosis, and also between vertical scar dehiscence/necrosis and subglandular implant placement (P-value = 0.04).

CONCLUSIONS

Safer secondary surgery can be offered to patients undergoing secondary aesthetic breast procedures, especially when the first augmentation surgery is unknown e.g. implant plane, type of pedicle used, the implant is large and subglandular, and capsulectomy is performed.

In vivo fluorescence imaging: success in preclinical imaging paves the way for clinical applications

Advances in diagnostic imaging have provided unprecedented opportunities to detect diseases at early stages and with high reliability. Diagnostic imaging is also crucial to monitoring the progress or remission of disease and thus is often the central basis of therapeutic decision-making. Currently, several diagnostic imaging modalities (computed tomography, magnetic resonance imaging, and positron emission tomography, among others) are routinely used in clinics and present their own advantages and limitations. In vivo near-infrared (NIR) fluorescence imaging has recently emerged as an attractive imaging modality combining low cost, high sensitivity, and relative safety. As a preclinical tool, it can be used to investigate disease mechanisms and for testing novel diagnostics and therapeutics prior to their clinical use. However, the limited depth of tissue penetration is a major challenge to efficient clinical use. Therefore, the current clinical use of fluorescence imaging is limited to a few applications such as image-guided surgery on tumors and retinal angiography, using FDA-approved dyes. Progress in fluorophore development and NIR imaging technologies holds promise to extend their clinical application to oncology, cardiovascular diseases, plastic surgery, and brain imaging, among others. Nanotechnology is expected to revolutionize diagnostic in vivo fluorescence imaging through targeted delivery of NIR fluorescent probes using antibody conjugation. In this review, we discuss the latest advances in in vivo fluorescence imaging technologies, NIR fluorescent probes, and current and future clinical applications.

Indocyanine Green Fluorescence Using in Conduit Reconstruction for Patients With Esophageal Cancer to Improve Short-Term Clinical Outcome: A Meta-Analysis

Objectives

This meta-analysis evaluated the short-term safety and efficacy of indocyanine green (ICG) fluorescence in gastric reconstruction to determine a suitable anastomotic position during esophagectomy.

Methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analyzes 2020 (PRISMA) were followed for this analysis.

Results

A total of 9 publications including 1,162 patients were included. The operation time and intraoperative blood loss were comparable in the ICG and control groups. There was also no significant difference in overall postoperative mortality, reoperation, arrhythmia, vocal cord paralysis, pneumonia, and surgical wound infection. The ICG group had a 2.66-day reduction in postoperative stay. The overall anastomotic leak (AL) was 17.6% (n = 131) in the control group and 4.5% (n = 19) in the ICG group with a relative risk (RR) of 0.29 (95% CI 0.18–0.47). A subgroup analysis showed that the application of ICG in cervical anastomosis significantly reduced the incidence of AL (RR of 0.31, 95% CI 0.18–0.52), but for intrathoracic anastomosis, the RR 0.35 was not significant (95% CI 0.09–1.43). Compared to an RR of 0.35 in publications with a sample size of <50, a sample size of >50 had a lower RR of 0.24 (95% CI 0.12–0.48). Regarding intervention time of ICG, the application of ICG both before and after gastric construction had a better RR of 0.25 (95% CI 0.07–0.89).

Conclusions

The application of ICG fluorescence could effectively reduce the incidence of AL and shorten the postoperative hospital stay for patients undergoing cervical anastomosis but was not effective for patients undergoing intrathoracic anastomosis. The application of ICG fluorescence before and after gastric management can better prevent AL.

Systematic Review Registration

PROSPERO, CRD:42021244819.

Role of Qualitative and Quantitative Indocyanine Green Angiography to Assess Mastectomy Skin Flaps Perfusion in Nipple/Skin-Sparing and Skin-Reducing Mastectomies with Implant-Based Breast Reconstruction

Methods

Consecutive women scheduled for nipple/skin-sparing/skin-reducing mastectomy between May 2020 and April 2021 were prospectively enrolled. Patients were divided into Group 1 in the absence of superficial and full-thickness necrosis (SN; FTN) and Group 2 in the presence of both. T1 (time between ICG injection and the initial perfusion of the least perfused MSF area), ICG-Q1, and ICG-Q% (absolute and relative perfusion values of the least vascularized area) were collected.

Results

38 breasts were considered. FTN was reported in 4 breasts (10.5%) and SN in 3 (7.9%). The two groups statistically differ in T1 (Group2 > Group1) and ICG-Q% (Group1 > Group2) (p < 0.05). T1 could statistically predict ICG-Q1 and ICG-Q%. Both quantitative values have a sensitivity of 57% and a NPV of 89%; ICG-Q% shows higher specificity (81% vs 77%) and PPV (40% vs 36%).

Conclusions

Quantitative ICG angiography may additionally reduce MSF necrosis. Moreover, longer T1 may indicate possible postoperative necrosis. Considering these factors, intraoperative changes of reconstructive strategy could be adopted to reduce reconstructive failure.

Membrane Cholesterol Enrichment of Red Blood Cell-Derived Microparticles Results in Prolonged Circulation

Particles fabricated from red blood cells (RBCs) can serve as vehicles for delivery of various biomedical cargos. Flipping of phosphatidylserine (PS) from the inner to the outer membrane leaflet normally occurs during the fabrication of such particles. PS externalization is a signal for phagocytic removal of the particles from circulation. Herein, we demonstrate that membrane cholesterol enrichment can mitigate the outward display of PS on microparticles engineered from RBCs. Our in-vitro results show that the phagocytic uptake of cholesterol-enriched particles by murine macrophages takes place at a lowered rate, resulting in reduced uptake as compared to RBC-derived particles without cholesterol enrichment. When administered via tail-vein injection into healthy mice, the percent of injected dose (ID) per gram of extracted blood for cholesterol-enriched particles was ∼1.5 and 1.8 times higher than the particles without cholesterol enrichment at 4 and 24 h, respectively. At 24 h, ∼43% ID/g of the particles without cholesterol enrichment was eliminated or metabolized while ∼94% ID/g of the cholesterol-enriched particles were still retained in the body. These results indicate that membrane cholesterol enrichment is an effective method to reduce PS externalization on the surface of RBC-derived particles and increase their longevity in circulation.

Objective Perfusion Assessment in Gracilis Muscle Interposition—A Novel Software-Based Approach to Indocyanine Green Derived Near-Infrared Fluorescence in Reconstructive Surgery

Background: Gracilis muscle interposition (GMI) is an established treatment option for complex perineal fistulas and reconstruction. The outcome is limited by complications such as necrosis, impaired wound healing and fistula persistence or recurrence. Quantifiable methods of assessing muscle flap perfusion intraoperatively are lacking. This study evaluates a novel and objective software-based assessment of indocyanine green near-infrared fluorescence (ICG-NIRF) in GMI. Methods: Intraoperative ICG-NIRF visualization data of five patients with inflammatory bowel disease (IBD) undergoing GMI for perineal fistula and reconstruction were analyzed retrospectively. A new software was utilized to generate perfusion curves for the specific regions of interest (ROIs) of each GMI by depicting the fluorescence intensity over time. Additionally, a pixel-to-pixel and perfusion zone analysis were performed. The findings were correlated with the clinical outcome. Results: Four patients underwent GMI without postoperative complications within 3 months. The novel perfusion indicators identified here (shape of the perfusion curve, maximum slope value, distribution and range) indicated adequate perfusion. In one patient, GMI failed. In this case, the perfusion indicators suggested impaired perfusion. Conclusions: We present a novel, software-based approach for ICG-NIRF perfusion assessment, identifying previously unknown objective indicators of muscle flap perfusion. Ready for intraoperative real-time use, this method has considerable potential to optimize GMI surgery in the future.

pHLIP ICG for delineation of tumors and blood flow during fluorescence-guided surgery

Fluorescence imaging has seen enduring use in blood flow visualization and is now finding a new range of applications in image-guided surgery. In this paper, we report a translational study of a new fluorescent agent for use in surgery, pHLIP ICG, where ICG (indocyanine green) is a surgical fluorescent dye used widely for imaging blood flow. We studied pHLIP ICG interaction with the cell membrane lipid bilayer, the pharmacology and toxicology in vitro and in vivo (mice and dogs), and the biodistribution and clearance of pHLIP ICG in mice. The pHLIP ICG tumor targeting and imaging efficacy studies were carried out in several murine and human mouse tumor models. Blood vessels were imaged in mice and pigs. Clinical Stryker imaging instruments for endoscopy and open surgery were used in the study. Intravenously administered pHLIP ICG exhibits a multi-hour circulation half-life, offering protracted delineation of vasculature. As it clears from the blood, pHLIP ICG targets tumors and tumor stroma, marking them for surgical removal. pHLIP ICG is non-toxic, marks blood flow for hours after injection, and effectively delineates tumors for improved resection on the day after administration.

Is It Reasonable to Use Indocyanine Green Fluorescence Imaging to Determine the Border of Pedicled TRAM Flap Zone IV?

Background:

The contralateral lateral section (zone IV) of a pedicled transverse rectus abdominis musculocutaneous (TRAM) flap is generally removed intraoperatively. The border of zone IV is usually identified anatomically using the Hartrampf classification. In this study, we used the indocyanine green (ICG) fluorescence method to determine the border of zone IV and find the correlation with clinical flap outcome.

Methods:

The study recruited breast cancer patients who underwent a pedicled TRAM flap reconstruction. The border of zone IV was identified using the intraoperative ICG fluorescence imaging. The medial border of the removed specimen was sent for a pathological examination of vascular density.

Results:

A total of 29 patients underwent a pedicled TRAM reconstruction. In 16 patients, the border of zone IV identified by ICG fluorescent imaging was identical to the anatomical border. The ICG imaging showed distinct perfusion patterns, which we divided into 4 categories: sequential, simultaneous, low midline scar, and delayed pattern. Overall, there were no patient with total flap loss, 1 patient had a partial flap loss and 4 patients had a fat necrosis. Neither the ICG perfusion time nor the pathological vascular density correlates with the clinical flap outcome. The delayed ICG perfusion pattern (category IV) has the highest fat necrosis rate, although it is not statistically significant.

Conclusions:

In this study, more than half of the patients have ICG perfusion corresponding with the Hartrampf zone, which reflected the conventional practice of zone IV pedicled TRAM flap removal. Some ICG perfusion patterns could be helpful, especially in low midline and delayed pattern.

Chest wall perforator flaps in partial breast reconstruction after breast conservation surgery: an additional oncoplastic surgical option

Partial breast reconstruction using chest wall perforator flaps (CWPF) is a recent option used by breast surgeons, mainly for lateral quadrant defects with a relatively large volume of excision. We report a single-centre experience of CWPF with surgery details, complications, re-excision, aesthetic and oncological outcomes.

This was a prospective observational cohort study of patients who had undergone breast conservation surgery (BCS) plus CWPF reconstruction. All variables were recorded prospectively in the institutional database. A survey was done to analyse patient satisfaction at about 6 months after completion of radiotherapy.

Forty patients had CWPF based reconstruction in 3 years. 57.5 % of patients had lateral intercostal artery perforator (LICAP) flap, 5% had lateral thoracic artery perforator (LTAP) flap, 27.5% had combined LICAP plus LTAP and 10% patients had anterior intercostal artery perforator (AICAP) flap. Tumour excision cavity defect was of the lateral quadrant in 82.5%, central quadrant in 10% and medial quadrant in 7.5% of patients. The margin was positive for five patients, out of which four required cavity shave and one had a mastectomy. One patient had complete flap loss, and two patients developed surgical site infection. 96% of patients were satisfied with the scar, and 88% were happy with the treated breast in comparison to the opposite breast. 92% were comfortable going out in public and felt that in retrospect their decision not to have a mastectomy was correct. With a median follow up of 18 (10, 22) months, one patient died, and four had recurrences.

CWPF may be used for partial breast reconstruction in the small non-ptotic breast with excellent outcome and high patient satisfaction scores.

Perspective on optical imaging for functional assessment in musculoskeletal extremity trauma surgery

SIGNIFICANCE

Extremity injury represents the leading cause of trauma hospitalizations among adults under the age of 65 years, and long-term impairments are often substantial. Restoring function depends, in large part, on bone and soft tissue healing. Thus, decisions around treatment strategy are based on assessment of the healing potential of injured bone and/or soft tissue. However, at the present, this assessment is based on subjective clinical clues and/or cadaveric studies without any objective measure. Optical imaging is an ideal method to solve several of these issues.

AIM

The aim is to highlight the current challenges in assessing bone and tissue perfusion/viability and the potentially high impact applications for optical imaging in orthopaedic surgery.

APPROACH

The prospective will review the current challenges faced by the orthopaedic surgeon and briefly discuss optical imaging tools that have been published. With this in mind, it will suggest key research areas that could be evolved to help make surgical assessments more objective and quantitative.

RESULTS

Orthopaedic surgical procedures should benefit from incorporation of methods to measure functional blood perfusion or tissue metabolism. The types of measurements though can vary in the depth of tissue sampled, with some being quite superficial and others sensing several millimeters into the tissue. Most of these intrasurgical imaging tools represent an ideal way to improve surgical treatment of orthopaedic injuries due to their inherent point-of-care use and their compatibility with real-time management.

CONCLUSION

While there are several optical measurements to directly measure bone function, the choice of tools can determine also the signal strength and depth of sampling. For orthopaedic surgery, real-time data regarding bone and tissue perfusion should lead to more effective patient-specific management of common orthopaedic conditions, requiring deeper penetrance commonly seen with indocyanine green imaging. This will lower morbidity and result in decreased variability associated with how these conditions are managed.

Serial Perioperative Assessment of Free Flap Perfusion With Laser Angiography

Study Design

Prospective cohort study.

Objective

Reconstruction with microvascular free flaps is quite predictable but excessive fluids intraoperatively and excessive use of vasopressors have been implicated in postoperative complications. However, vasopressors assist in limiting fluid administration and counteract vasodilatory effects of general anesthetics, while maintaining proper intravascular volume. This is of paramount importance during surgery to ensure adequate tissue and organ perfusion. The purpose of this study is to quantify perfusion changes in free flaps at specific time points during peri- and postoperative periods, incorporating SPY technology.

Methods

A prospective study of patients who underwent free flap reconstruction was conducted (n = 9), using SPY laser angiography with indocyanine green to assess effects of general anesthetics and vasopressors on flap perfusion. Free flaps were evaluated prior to pedicle division, after inset and anastomosis, and in the immediate postoperative setting. Mean perfusion, mean arterial pressure, total operative time, fluid shifts, and vasopressor use were recorded. Data were analyzed with univariate and multivariable analyses.

Results

Those with major complications in this cohort, on average received less vasopressors, had shorter operation times and less blood loss, however, they received more fluids intraoperatively.

Conclusion

Changes in mean perfusion to the free flap during the intraoperative and immediate postoperative period are nominal.

Intraoperative indocyanine green fluorescence imaging in breast surgery

Background

Since postoperative complications after reconstructive breast surgery are often related to drastic increases of patient suffering and treatment costs, several devices were developed in order to avoid them. In this respect, the intraoperative fluorescence angiography with indocyanine green (ICG) provides promising results by detecting ischemic skin intraoperatively.

Methods

Women who underwent reconstructive breast surgery at the breast center at Charité between April and December 2017 were included in the analysis. General patient characteristics, medical history, type of surgery, as well as postoperative parameters, complications and patient reported outcomes were compared between patients operated using ICG fluorescence angiography and conventionally operated patients.

Results

Among 68 patients with breast reconstruction 36 (52.9%) were operated with the ICG angiography device and 32 (47.1%) without. No significant differences regarding patient demographics, medical history, and surgical procedure were found. Wound healing disorders occurred in 11.1% of the ICG group and in 9.4% of the control group. About 11% of both groups developed major complications which required revision surgery. Complication rates and patient reported outcome did not differ significantly. Across both groups, only the risk factor resection weight (≥ 500 g) was significantly associated with wound healing disorders (RR = 6.80; 95%CI 1.93–23.81; p = 0.022).

Conclusion

The purchase of a device for intraoperative ICG angiography might not be reasonable for every breast center. Further research in a larger cohort and prospective manner should be done to determine if the addition of ICG to breast reconstructive surgery in the German setting really leads to improved patient care.

Indocyanine green angiography for preventing postoperative mastectomy skin flap necrosis in immediate breast reconstruction

BACKGROUND

Breast cancer will affect one in eight women during their lifetime. The opportunity to restore the removed tissue and cosmetic appearance is provided by reconstructive breast surgery following skin-sparing mastectomy (SSM). Mastectomy skin flap necrosis (MSFN) is a common complication following SSM breast reconstruction. This postoperative complication can be prevented by intraoperative assessment of mastectomy skin flap viability and intervention when tissue perfusion is compromised. Indocyanine green fluorescence angiography is presumed to be a better predictor of MSFN compared to clinical evaluation alone.

OBJECTIVES

To assess the effects of indocyanine green fluorescence angiography (ICGA) for preventing mastectomy skin flap necrosis in women undergoing immediate breast reconstruction following skin-sparing mastectomy. To summarise the different ICGA protocols available for assessment of mastectomy skin flap perfusion in women undergoing immediate breast reconstructions following skin-sparing mastectomy.

SEARCH METHODS

We searched the Cochrane Breast Cancer Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL; Issue 3, 2019), MEDLINE, Embase, the World Health Organization's International Clinical Trials Registry Platform (ICTRP) and Clinicaltrials.gov in April 2019. In addition, we searched reference lists of published studies.

SELECTION CRITERIA

We included studies that compared the use of ICGA to clinical evaluation to assess mastectomy skin vascularisation and recruited women undergoing immediate autologous or prosthetic reconstructive surgery following SSM for confirmed breast malignancy or high risk of developing breast cancer.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the risk of bias of the included nonrandomised studies and extracted data on postoperative outcomes, including postoperative MSFN, reoperation, autologous flap necrosis, dehiscence, infection, haematoma and seroma, and patient-related outcomes. The quality of the evidence was assessed using the GRADE approach and we constructed two 'Summary of finding's tables: one for the comparison of ICGA to clinical evaluation on a per patient basis and one on a per breast basis.

MAIN RESULTS

Nine nonrandomised cohort studies met the inclusion criteria and involved a total of 1589 women with 2199 breast reconstructions. We included seven retrospective and two prospective cohort studies. Six studies reported the number of MSFN on a per breast basis for a total of 1435 breasts and three studies reported the number of MSFN on a per patient basis for a total of 573 women. Five studies reported the number of other complications on a per breast basis for a total of 1370 breasts and four studies reported the number on a per patient basis for a total of 613 patients. Therefore, we decided to pool data separately. Risk of bias for each included nonrandomised study was assessed using the Newcastle-Ottawa Scale for cohort studies. There was serious concern with risk of bias due to the nonrandomised study design of all included studies and the low comparability of cohorts in most studies. The quality of the evidence was found to be very low, after downgrading the quality of evidence twice for imprecision based on the small sample sizes and low number of events in the included studies. Postoperative complications on a per patient basis We are uncertain about the effect of ICGA on MSFN (RR 0.79, 95% CI 0.40 to 1.56; three studies, 573 participants: very low quality of evidence), infection rates (RR 0.91, 95% CI 0.60 to 1.40; four studies, 613 participants: very low quality of evidence), haematoma rates (RR 0.87, 95% CI 0.30 to 2.53; two studies, 459 participants: very low quality of evidence) and seroma rates (RR 1.68, 95% CI 0.41 to 6.80; two studies, 408 participants: very low quality of evidence) compared to the clinical group. We found evidence that ICGA may reduce reoperation rates (RR 0.50, 95% CI 0.35 to 0.72; four studies, 613 participants: very low quality of evidence). One study considered dehiscence as an outcome. In this single study, dehiscence was observed in 2.2% of participants (4/184) in the ICGA group compared to 0.5% of participants (1/184) in the clinical group (P = 0.372). The RR was 4.00 (95% CI 0.45 to 35.45; one study; 368 participants; very low quality of evidence). Postoperative complications on a per breast basis We found evidence that ICGA may reduce MSFN (RR 0.62, 95% CI 0.48 to 0.82; six studies, 1435 breasts: very low quality of evidence), may reduce reoperation rates (RR 0.65, 95% CI 0.47 to 0.92; five studies, 1370 breasts: very low quality of evidence) and may reduce infection rates (RR 0.65, 95% CI 0.44 to 0.97; five studies, 1370 breasts: very low quality of evidence) compared to the clinical group. We are uncertain about the effect of ICGA on haematoma rates (RR 1.53, CI 95% 0.47 to 4.95; four studies, 1042 breasts: very low quality of evidence) and seroma rates (RR 0.71, 95% CI 0.37 to 1.35; two studies, 528 breasts: very low quality of evidence). None of the studies reported patient-related outcomes. ICGA protocols: eight studies used the SPY System and one study used the Photodynamic Eye imaging system (PDE) to assess MSFN. ICGA protocols in the included studies were not extensively described in most studies.

AUTHORS' CONCLUSIONS

Although mastectomy skin flap perfusion is performed more frequently using ICGA as a helpful tool, there is a lack of high-quality evidence in the context of randomised controlled trials. The quality of evidence in this review is very low, since only nonrandomised cohort studies have been included. With the results from this review, no conclusions can be drawn about what method of assessment is best to use during breast reconstructive surgery. High-quality randomised controlled studies that compare the use of ICGA to assess MSFN compared to clinical evaluation are needed.

Visualized bilateral breast reconstruction by propeller thoracodorsal artery perforator flaps

Thoracodorsal artery perforator (TAP) flaps are versatile flaps that provide a consistent and aesthetically pleasing breast reconstruction. We prefer the TAP flap to the latissimus dorsi (LD) flap due to the morbidity associated with the LD flap. In this paper we aim to show how we perform bilateral TAP flap breast reconstruction and present our preliminary results from 32 bilateral reconstructions in 16 patients. The TAP flap breast reconstruction can be performed as a direct-to-implant or a delayed procedure depending on patient factors. Color Doppler ultrasonography (CDU) is used in the preoperative planning which promotes the safety and reliability of the flap by mapping perforators thus enabling faster dissection. The bilateral TAP flap breast reconstruction is usually performed in three steps: (I) raising the flaps at the recipient site; (II) rotating the TAP flaps and (III) completion of the breast reconstruction.

Innovative DIEP flap perfusion evaluation tool: Qualitative and quantitative analysis of indocyanine green-based fluorescence angiography with the SPY-Q proprietary software

BACKGROUND

Perfusion-related complications remain the most common concern in DIEP flap breast reconstruction. Indocyanine green-based fluorescence angiography can be used for the real-time intra operative assessment of flap perfusion. The SPY Elite system is the most widely used device in this setting. The main objective was to describe the use of SPY-Q proprietary software to perform qualitative and quantitative analysis of flap perfusion.

METHODS

This retrospective cohort study was performed at the Curie Institute between 2013 and 2017. We included patients undergoing unilateral DIEP flap breast reconstruction for whom indocyanine green-based angiography videos were of sufficient quality for analysis. Videos were recorded with the SPY Elite System and analyzed with SPY-Q proprietary software.

RESULTS

We included 40 patients. We used real-time dynamic color analysis to describe three different patterns of flap perfusion. SPY-Q proprietary software provides quantitative flap perfusion parameters. Our quantitative analysis confirmed that zone I is the best perfused part of the flap and zone IV the less perfused one. There was no significant association between flap perfusion pattern and perforator anatomy, patients' clinical characteristics or postoperative outcomes. After exploratory univariate analysis, quantitative perfusion parameters were significantly impaired in young patients with diabetes mellitus or under hormone therapy by tamoxifen.

CONCLUSIONS

We here describe a new approach to assess DIEP flap perfusion using the SPY Elite System proprietary software. It provides interesting qualitative and quantitative analysis that can be used in further studies to precisely assess DIEP flap perfusion.

Fluorescent imaging using indocyanine green during esophagectomy to prevent surgical morbidity: a systematic review and meta-analysis

Background

Fluorescent imaging using indocyanine green (ICG) is an emerging technique that aids the surgeon with intraoperative decision making during upper gastrointestinal cancer surgery. In this systematic review we aim to provide an overview of current practice of fluorescence imaging using ICG during esophagectomy, and to show how this technology can prevent surgical morbidity, such as anastomotic leakage, graft necrosis and chylothorax.

Methods

The PRISMA standard for systematic reviews was used. The PubMed and Embase database were searched to identify articles matching our systematic literature search. Two authors screened all included articles for eligibility. Risk of bias was assessed for all included articles.

Results

A total of 25 articles were included in this review: 22 articles on perfusion assessment, and three on the detection of chyle fistula. Five out of 22 articles concerning perfusion assessment evaluated fluorescence signals in quantitative values. In 20 articles the pooled incidence of anastomotic leakage and graft necrosis in the ICG group was 11.10% (95% CI: 8.06-15.09%) and in eight studies the pooled change in management rate was 24.55% (95% CI: 19.16-30.88%). After change in management, the pooled incidence of anastomotic leakage and graft necrosis was 14.08% (95% CI: 6.55-27.70%). A meta-analysis showed that less anastomotic leakages and graft necrosis occur in the ICG group (OR 0.30, 95% CI: 0.14-0.63). Three case-reports (N=3) were identified regarding chyle fistula detection, and ICG lymphography detected the thoracic duct in all cases and the chyle fistula in one case.

Conclusions

Fluorescence imaging using ICG is a promising and safe technology to reduce surgical morbidity after esophagectomy with continuity restoration. ICG fluorescence angiography showed a reduction in anastomotic leakage and graft necrosis. Future studies are needed to demonstrate the feasibility of ICG lymphography for chyle fistula detection.

Optimizing perioperative strategies to maximize success with prepectoral breast reconstruction

Implant based reconstruction is still the most commonly employed method of post mastectomy reconstruction in the United States and internationally. Mastectomy techniques are improving, and adjuncts such as tissue perfusion technology and biologic implants allow for re-evaluation of traditional reconstructive methods. Subpectoral implant placement is used in a large majority of patients undergoing implant based reconstruction. However, with the advent of acellular dermal matrix (ADM), a "sling" for the expander and implant can be placed with surgical precision to create the optimal breast pocket. This has allowed for placement of the breast prosthesis in a prepectoral anatomic plane. The benefits are clear: avoidance of animation deformities and a significant decrease in pain that results from pectoralis mobilization and spasm. Here, we discuss specific techniques to avoid pitfalls and optimize aesthetic results with prepectoral breast reconstruction. Patient selection, intra-operative mastectomy flap evaluation, modifications in expander and implant fill, and technique specifics all play a critical role in this new, and rapidly growing method for implant based breast reconstruction.

Use of indocyanine green fluorescence imaging to determine the area of bowel resection in non-occlusive mesenteric ischemia: A case report

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In cases of NOMI, it is difficult to determine the area of bowel resection.

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Using ICG fluorescence imaging, we can evaluate ischemia of the intestine.

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We adeptly resected the ischemic intestine in NOMI using ICG fluorescence imaging.

Introduction

Non-occlusive mesenteric ischemia (NOMI) is a type of acute intestinal ischemia, and its associated mortality is very high. In laparotomy of NOMI, we often have difficulty determining the area of bowel resection. We herein describe a case in which we detected the area of bowel resection using indocyanine green (ICG) fluorescence imaging.

Presentation of the case

An 89-year-old man diagnosed as having advanced gastric cancer underwent distal gastrectomy. On the night of postoperative day 4, he strongly complained of distention of the abdomen. The laboratory data indicated severe metabolic acidosis and dehydration. The abdominal computed tomography scan showed a dilated small bowel, but there were no specific signs suggestive of bowel necrosis. We suspected NOMI and decided to perform emergency laparotomy because we could not exclude the possibility of bowel necrosis. During the operation, we could not detect the necrotic bowel macroscopically. After injecting 2.5 mg of ICG, the ischemic area of the bowel became visible as a region with poor fluorescence emission using the Photodynamic Eye™ (Hamamatsu Photonics K.K.). We resected the ischemic bowel and performed anastomosis. We confirmed that he was alive at 4 months after the operation of NOMI.

Conclusion

Intraoperative ICG fluorescence imaging makes it possible to detect necrotic intestine that cannot be found with the naked eye. By using this method, planned reoperation to find any newly developed necrotic intestine might be unnecessary. Intraoperative ICG fluorescence imaging is useful for defining the area of ischemic bowel in a patient with NOMI.

Noncontact speckle contrast diffuse correlation tomography of blood flow distributions in tissues with arbitrary geometries

A noncontact electron multiplying charge-coupled-device (EMCCD)-based speckle contrast diffuse correlation tomography (scDCT) technology has been recently developed in our laboratory, allowing for noninvasive three-dimensional measurement of tissue blood flow distributions. One major remaining constraint in the scDCT is the assumption of a semi-infinite tissue volume with a flat surface, which affects the image reconstruction accuracy for tissues with irregular geometries. An advanced photometric stereo technique (PST) was integrated into the scDCT system to obtain the surface geometry in real time for image reconstruction. Computer simulations demonstrated that a priori knowledge of tissue surface geometry is crucial for precisely reconstructing the anomaly with blood flow contrast. Importantly, the innovative integration design with one single-EMCCD camera for both PST and scDCT data collection obviates the need for offline alignment of sources and detectors on the tissue boundary. The in vivo imaging capability of the updated scDCT is demonstrated by imaging dynamic changes in forearm blood flow distribution during a cuff-occlusion procedure. The feasibility and safety in clinical use are evidenced by intraoperative imaging of mastectomy skin flaps and comparison with fluorescence angiography.

The Utility of Intraoperative Near Infrared Fluorescence (NIR) Imaging with Indocyanine Green (ICG) for the Assessment of Kidney Allograft Perfusion

Background

Near infrared light (NIR) fluorescence imaging with indocyanine green (ICG) has been used in various aspects of surgery, such as in the assessment of vascular anastomosis, tissue perfusion, and the identification of lymph nodes. In this study we evaluated the utility of NIR/ICG fluorescence imaging in kidney transplantation.

Materials and Methods

NIR/ICG imaging was used to assess allograft perfusion in n=1 living donor (LDRT) and n=2 deceased donor (DDRT) renal transplantations, performed in February 2017. The allograft arterial and venous anastomoses were done end-to-side to the corresponding recipient external iliacs, and ureteroneocystostomies were performed for urinary reconstructions. After completion of vascular anastomosis, ICG was given as intravenous bolus at 0.3mg/kg, followed by visual assessment of tissue perfusion and vascular anastomoses at 1-minute interval using fluorescence imaging (KARL STORZ NIR/ICG System).

Results

Homogenous global fluorescence of the allograft and vascular anastomosis was observed in all 3 cases. Immediate postoperative perfusion studies showed patent inflow and outflow vessels and well perfused transplanted kidneys. Immediate graft function was observed in 2 recipients (1 LDRT and 1 DDRT). One session of haemodialysis was performed in 1 DDRT recipient, for high serum potassium in the immediate postoperative setting, who otherwise had good urine output and serially declining serum creatinine.

Conclusions

NIR/ICG fluorescence imaging can be useful in renal transplantation for the intraoperative assessment of allograft perfusion, especially in complex cases with multiple renal arteries and vascular reconstructions.

Systematic review of methodologies used to assess mastectomy flap viability

BACKGROUND

Accurate prediction of mastectomy skin flap viability is vital as necrosis causes significant morbidity, potentially compromising results and delaying oncological management. Traditionally assessed by clinical judgement, a more objective evaluation can be provided using intraoperative imaging modalities. This systematic review aimed to compare all intraoperative techniques for assessment of mastectomy flap viability.

METHODS

A systematic literature review was performed using MEDLINE and Embase databases. Primary outcomes reported included specificity, sensitivity and predictive values of each test, and mean rates of mastectomy flap necrosis and reoperation. Secondary outcomes included cost analysis.

RESULTS

Some 18 studies were included. Designs were prospective cohort study (8), retrospective case series (4), prospective case series (3), retrospective case-control study (1), prospective pilot trial (1) and cost analysis study (1). The studies compared indocyanine green angiography (ICGA) (16 studies) and fluorescein dye angiography (FA) (3 studies) with clinical judgement. Sensitivity and specificity were highest for ICGA (5 studies) ranging from 38 to 100 and 68 to 91 per cent respectively. Both methods overpredicted necrosis. Mean rates of flap necrosis and reoperation decreased with ICGA (7·9 and 5·5 per cent respectively) and FA (3 and 0 per cent) compared with clinical judgement (19·4 and 12·9 per cent). Two studies were designed to define numerical parameters corresponding to perfusion using intraoperative techniques. Two studies performed a cost analysis for ICGA; one claimed a cost benefit and the other advocated its use in high-risk patients only.

CONCLUSION

ICGA and FA are potentially useful tools for mastectomy flap assessment. However, the predictive accuracy is subject to the specific settings and model of equipment used. Current recommendations support their use in high-risk patients.

Development of a modular fluorescence overlay tissue imaging system for wide-field intraoperative surgical guidance

Fluorescence imaging is a well-established optical modality that has been used to localize and track fluorophores in vivo and has demonstrated great potential for surgical guidance. Despite the variety of fluorophores currently being researched, many existing intraoperative fluorescence imaging systems are specifically designed for a limited number of applications. We present a modular wide-field fluorescence overlay tissue imaging system for intraoperative surgical guidance that is comprised of commercially available standardized components. Its modular layout allows for the accommodation of a broad range of fluorophores, fields of view (FOV), and spatial resolutions while maintaining an integrated portable design for intraoperative use. Measurements are automatic and feature a real-time projection overlay technique that intuitively displays fluorescence maps directly onto a [Formula: see text] FOV from a working distance of 35 cm. At a 20-ms exposure time, [Formula: see text] samples of indocyanine green could be measured with high signal-to-noise ratio and was later tested in an in vivo mouse model before finally being demonstrated for intraoperative autofluorescence imaging of human soft tissue sarcoma margins. The system's modular design and ability to enable naked-eye visualization of wide-field fluorescence allow for the flexibility to adapt to numerous clinical applications and can potentially extend the adoption of fluorescence imaging for intraoperative use.

How to optimize aesthetic outcomes in implant-based breast reconstruction

The evolution of breast reconstructive surgery keeps pace with the evolution of breast oncologic surgery. The reconstructive choice should always balance the optimal local control of disease and the best cosmetic result, reflecting an informed decision that is shared with the patient, who is always at the center of the decision-making process. Implant-based breast reconstruction following mastectomy represents a complex choice. In order to obtain optimal results, the following considerations are mandatory: thorough preoperative planning, a complete knowledge of the devices that are used, accurately performed surgery, and appropriate follow-up.

Fluorescence-guided surgery for cancer patients: a proof of concept study on human xenografts in mice and spontaneous tumors in pets

Surgery is often the first treatment option for patients with cancer. Patient survival essentially depends on the completeness of tumor resection. This is a major challenge, particularly in cases of peritoneal carcinomatosis, where tumors are widely disseminated in the large peritoneal cavity. Any development to help surgeons visualize these residual cells would improve the completeness of the surgery. For non-disseminated tumors, imaging could be used to ensure that the tumor margins and the draining lymph nodes are free of tumor deposits.

Near-infrared fluorescence imaging has been shown to be one of the most convenient imaging modalities. Our aim was to evaluate the efficacy of a near-infrared fluorescent probe targeting the αvβ3 integrins (Angiostamp™) for intraoperative detection of tumors using the Fluobeam® device.

We determined whether different human tumor nodules from various origins could be detected in xenograft mouse models using both cancer cell lines and patient-derived tumor cells. We found that xenografts could be imaged by fluorescent staining irrespective of their integrin expression levels. This suggests imaging of the associated angiogenesis of the tumor and a broader potential utilization of Angiostamp™. We therefore performed a veterinary clinical trial in cats and dogs with local tumors or with spontaneous disseminated peritoneal carcinomatosis. Our results demonstrate that the probe can specifically visualize both breast and ovarian nodules, and suggest that Angiostamp™ is a powerful fluorescent contrast agent that could be used in both human and veterinary clinical trials for intraoperative detection of tumors.

Viability of five different pre- and intraoperative imaging methods for autologous breast reconstruction

Background

Autologous breast reconstruction is an integral part in the treatment of breast cancer. While computed tomography angiography (CTA) is an established preoperative diagnostic tool for microsurgeons, no study has so far evaluated and compared five different imaging methods and their value for the reconstructive team. In order to determine the feasibility of each of the tools for routine or specialized diagnostic application, the methods' efficiency and informative value were analyzed.

Methods

We retrospectively analyzed imaging data of 41 patients used for perforator location and assessment for regional perfusion and vessel patency in patients undergoing autologous breast reconstruction with deep inferior epigastric perforator flap (DIEP), transverse rectus abdominis muscle flap (TRAM), or transverse myocutaneous gracilis flap (TMG). Five different imaging techniques were used: hand held Doppler (HHD), CT angiography (CTA), macroscopic indocyanine green (ICG) video angiography, microscope-integrated ICG video angiography, and laser Doppler imaging (LDI).

Results

CTA proved to be the best tool for preoperative determination of the highly variable anatomy of the abdominal region, whereas HHD showed the same information on perforator localization with some false-positive results. Intraoperative HHD was an excellent tool for dissection and vessel patency judgment. Microscope-integrated ICG was an excellent tool to document the patency of microanastomoses. In our series, macroscopic perfusion measurement with ICG or LDI was only justified in special situations, where information on perfusion of abdominal or mastectomy flaps was required. LDI did not add any additional information.

Conclusion

Preoperative assessment should be performed by CTA with verification of the perforator location by HHD. Intraoperative HHD and microscope-integrated ICG contribute most toward the evaluation of vessel patency. ICG and LDI should only be used for special indications.