The Impact of Indocyanine-Green Fluorescence Angiography on Intraoperative Decision-Making and Postoperative Outcome in Free Flap Surgery

Optimizing ALT Flap Harvest: The Role of Combined Preoperative Duplex Ultrasound and Intraoperative ICG Angiography for Perforator Selection

Planning and harvesting anterolateral thigh flaps (ALT) requires precise perforator selection and accurate tissue perfusion assessment. Unfortunately, variable perforator anatomy and perfusion patterns often result in extensive exploratory dissection. We aimed to assess the impact of preoperative color-coded duplex sonography (CCDS) and intraoperative indocyanine green fluorescence angiography (ICGFA) on perforator selection and operative morbidity. Fifty-three ALTs were performed with preoperative CCDS and intraoperative ICGFA. Flaps had one, two, or three suitable perforators. Additional perforators were either included, or ligated following temporary clamping with ICGFA-based perfusion assessment. If perfusion was sufficient, further dissecting of additional perforators of unfavorable course was abstained from. The impact on perforator selection and operative outcomes was studied. Seven flaps were raised on a single, 34 on 2, and 12 on 3 perforators. There was no flap loss. Comparing the subgroups of fully dissected versus partially clamped and subsequently ligated perforators revealed significantly shorter harvest times in the latter (268 ± 71 versus 216 ± 47 min, p = 0.006). The unnecessary dissection of 21 additional perforators in 16 cases was avoided. Combining preoperative CCDS and intraoperative ICGFA aids in designing ALTs and guarantees the intraoperative selection of suitable perforators. This allows for significant reductions in operative time and donor-site morbidity by limiting unnecessary dissection.

Reconstruction of Posttraumatic Distal Limb Defects With Free Superficial Circumflex Iliac Artery Perforator Flap

INTRODUCTION

Soft tissue defects in the distal limbs are common after traumatic injury. Repairing such defects is challenging because of the lack of adjacent soft tissue for direct closure or use of a local flap, and functional and aesthetic issues are more prominent in the hands and feet. Thin, unbulky free tissue transfer is ideal for achieving functional and aesthetically pleasing reconstructions. This study reports the use of free superficial circumflex iliac artery perforator (SCIP) flap to reconstruct posttraumatic distal limb defect.

PATIENTS AND METHODS

Thirteen patients with distal limb defects following traumatic injury underwent microsurgical reconstruction with SCIP flap between 2017 and 2022. The defects were located in the upper extremities in 8 patients and lower extremities in 5 patients. Flap thinning was performed to minimize bulkiness, thus restoring functionality and an aesthetically satisfactory appearance.

RESULTS

The patients' average age was 39.8 ± 15.3 years. The average flap size was 13.5 ± 3.4 × 6.7 ± 1.5 cm, and the average pedicle length was 5.2 ± 1.3 cm. Two flaps failed because of unsalvageable venous thrombosis, whereas 2 flaps had salvageable vessel thrombosis. Other flaps survived without major complications. During the average follow-up duration of 7.4± 4.8 months, the functional and aesthetic outcomes were satisfactory after an average of 1 ± 1.2 times of flap revisions.

CONCLUSIONS

With a thin skin paddle, SCIP flap is an available option for posttraumatic distal limb defect reconstruction without much effort of further revisions.

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.

Reduce Flap Necrosis After Autologous Breast Reconstruction: A Systematic Review

BACKGROUND

Autologous breast reconstruction provides substantial benefits in terms of aesthetics and longevity. However, the risk of flap necrosis poses potential challenges to patients' appearance and psychological well-being, while also escalating health care costs. Consequently, examining the risk factors, assessment techniques, and therapeutic approaches for flap necrosis is critically important.

METHOD

The authors conducted a comprehensive search for relevant studies from January 2010 to August 2024 using PubMed, Web of Science, and the Cochrane Library. The search terms included "autologous breast reconstruction", "flap necrosis", "risk factor", "assessment", and "treatment". The authors initially screened titles and abstracts, followed by a detailed review by 3 investigators to determine the studies that met the inclusion criteria.

RESULT

A total of 68 studies were ultimately selected for analysis. Identified risk factors for flap necrosis include smoking, advanced age, obesity, diabetes, large breast volume, previous radiotherapy, and abdominal surgery. Various assessment methods (e.g., preoperative imaging, intraoperative blood flow monitoring, and postoperative evaluations) can enhance flap survival. The review also covered surgical treatment strategies and non-surgical interventions, including local wound care, hyperbaric oxygen therapy, and pharmacological treatments.

CONCLUSION

This review highlights the critical role of thorough planning and management in minimizing the risk of flap necrosis after autologous breast reconstruction. Effective preoperative assessments, perioperative monitoring, and specific postoperative interventions can significantly lower the incidence of flap necrosis.

Advancing indocyanine green fluorescence flap perfusion assessment via near infrared signal quantification

Introduction

Intraoperative indocyanine green fluorescence angiography (ICGFA) perfusion assessment has been demonstrated to reduce complications in reconstructive surgery. This study sought to advance ICGFA flap perfusion assessment via quantification methodologies.

Method

Patients undergoing pedicled and free flap reconstruction were subjected to intraoperative ICGFA flap perfusion assessment using either an open or endoscopic system. Patient demographics, clinical impact of ICGFA and outcomes were documented. From the ICGFA recordings, fluorescence signal quality, as well as inflow/outflow milestones for the flap and surrounding (control) tissue were computationally quantified post hoc and compared on a region of interest (ROI) level. Further software development intended full flap quantification, metric computation and heatmap generation.

Results

Fifteen patients underwent ICGFA assessment at reconstruction (8 head and neck, 6 breast and 1 perineum) including 10 free and 5 pedicled flaps. Visual ICGFA interpretation altered on-table management in 33.3% of cases, with flap edges trimmed in 4 and a re-anastomosis in 1 patient. One patient suffered post-operative flap dehiscence. Laparoscopic camera use proved feasible but recorded a lower quality signal than the open system.Using established and novel metrics, objective ICGFA signal ROI quantification permitted perfusion comparisons between the flap and surrounding tissue. Full flap assessment feasibility was demonstrated by computing all pixels and subsequent outputs summarisation as heatmaps.

Conclusion

This trial demonstrated the feasibility and potential for ICGFA with operator based and quantitative flap perfusion assessment across several reconstructive applications. Further development and implementation of these computational methods requires technique and device standardisation.

The free vastus lateralis-And conjoined vastus lateralis anterolateral thigh/tensor fascia lata flap for oncological chest wall reconstruction

INTRODUCTION

A reconstructive option for extensive chest wall reconstruction is the free myocutaneous vastus lateralis muscle (VL) flap which can be performed in isolation or in conjunction with a fasciocutaneus anterolateral thigh (cVLALT) and/or myofasciocutaneous tensor fascia lata flap (cVLTFL). We aimed to directly compare the outcomes of these reconstructive options.

METHODS

Patients who underwent oncological chest wall reconstruction with a free VL, cVLALT, or cVLTFL flap between February 2010 and 2022 were included in this retrospective study. Patient demographics, surgical characteristics, as well as medical and reconstructive outcomes, were evaluated. The operative outcomes between myocutaneous VL, cVLALT, and cVLTFL flap reconstructions were compared.

RESULTS

A total of 41 patients underwent chest wall reconstruction with a free myocutaneous VL (n = 25; 61%), cVLALT (n = 14; 34%), or cVLTFL Three acute flap thromboses occurred in the entire cohort (3/41, 7%), with one myocutaneous VL flap failing because of recurrent venous thrombosis during the salvage procedure. Total flap necrosis was seen in two cases (5%; VL flap: n = 1; cVLALT flap: n = 1), and partial flap necrosis in one VL flap (1/25, 4%) and in the distal ALT portion of three cVLALT flaps (3/14, 21%). No significant difference was seen between isolated VL and conjoined VL flaps regarding the partial (p = .28) or total flap necrosis rate (p = .9).

CONCLUSION

The free (conjoined) VL flap provides reliable outcomes for obliterating dead space achieving durable reconstruction of complex chest wall defects.

Advancing DIEP Flap Monitoring with Optical Imaging Techniques: A Narrative Review

OBJECTIVES

This review aims to explore recent advancements in optical imaging techniques for monitoring the viability of Deep Inferior Epigastric Perforator (DIEP) flap reconstruction. The objectives include highlighting the principles, applications, and clinical utility of optical imaging modalities such as near-infrared spectroscopy (NIRS), indocyanine green (ICG) fluorescence angiography, laser speckle contrast imaging (LSCI), hyperspectral imaging (HSI), dynamic infrared thermography (DIRT), and short-wave infrared thermography (SWIR) in assessing tissue perfusion and oxygenation. Additionally, this review aims to discuss the potential of these techniques in enhancing surgical outcomes by enabling timely intervention in cases of compromised flap perfusion.

MATERIALS AND METHODS

A comprehensive literature review was conducted to identify studies focusing on optical imaging techniques for monitoring DIEP flap viability. We searched PubMed, MEDLINE, and relevant databases, including Google Scholar, Web of Science, Scopus, PsycINFO, IEEE Xplore, and ProQuest Dissertations & Theses, among others, using specific keywords related to optical imaging, DIEP flap reconstruction, tissue perfusion, and surgical outcomes. This extensive search ensured we gathered comprehensive data for our analysis. Articles discussing the principles, applications, and clinical use of NIRS, ICG fluorescence angiography, LSCI, HSI, DIRT, and SWIR in DIEP flap monitoring were selected for inclusion. Data regarding the techniques' effectiveness, advantages, limitations, and potential impact on surgical decision-making were extracted and synthesized.

RESULTS

Optical imaging modalities, including NIRS, ICG fluorescence angiography, LSCI, HSI, DIRT, and SWIR offer a non- or minimal-invasive, real-time assessment of tissue perfusion and oxygenation in DIEP flap reconstruction. These techniques provide objective and quantitative data, enabling surgeons to monitor flap viability accurately. Studies have demonstrated the effectiveness of optical imaging in detecting compromised perfusion and facilitating timely intervention, thereby reducing the risk of flap complications such as partial or total loss. Furthermore, optical imaging modalities have shown promise in improving surgical outcomes by guiding intraoperative decision-making and optimizing patient care.

CONCLUSIONS

Recent advancements in optical imaging techniques present valuable tools for monitoring the viability of DIEP flap reconstruction. NIRS, ICG fluorescence angiography, LSCI, HSI, DIRT, and SWIR offer a non- or minimal-invasive, real-time assessment of tissue perfusion and oxygenation, enabling accurate evaluation of flap viability. These modalities have the potential to enhance surgical outcomes by facilitating timely intervention in cases of compromised perfusion, thereby reducing the risk of flap complications. Incorporating optical imaging into clinical practice can provide surgeons with objective and quantitative data, assisting in informed decision-making for optimal patient care in DIEP flap reconstruction surgeries.

A Shaped Pectoralis Major Muscle Flap under Indocyanine Green Fluorescence Angiography for Sternal Wound Infection

The treatment of a sternal wound infection is challenging because it requires radical debridement and reconstruction with a well-vascularized flap. The defects after debridement are three-dimensionally complex, especially if synthetic grafts are involved. Although the pectoralis major muscle (PMM) flap is useful for reconstruction, it is difficult to fill up the complex dead space surrounding the vascular prosthesis when using a conventional PMM flap. Herein, we describe a new technique of splitting and shaping the PMM flap to fit the complex defect. Intraoperative indocyanine green fluorescence angiography was used to assess dynamic blood flow of the PMM supplied by internal mammary artery perforators. This technique allows the PMM flap to be split and shaped to securely fit the dead space, which may improve the healing rate.

[Modern concepts of interdisciplinary extremity reconstruction in open fractures]

The orthoplastic approach involves the collaboration of orthopedic/trauma surgeons, vascular surgeons and reconstructive microsurgeons. In cases of complex limb fractures, the aims are to optimize blood flow, restore bone stability, reconstruct soft tissue defects, and enhance function and sensitivity. The early administration of antibiotics and a timely, high-quality debridement after initial interdisciplinary assessment are carried out. This is followed by fracture stabilization and temporary wound coverage in order to plan the definitive interdisciplinary procedure. This includes definitive osteosynthesis and soft tissue reconstruction, using local tissue transfer if feasible, or free tissue transfer in cases of extensive trauma zones. The orthoplastic approach allows for faster definitive stabilization, fewer operations, shorter hospital stays, lower complication and revision rates, higher cost-effectiveness and improved long-term function.

Intraoperative Indocyanine Green Angiography Facilitates Flap Fenestration and Facial Organ Fabrication in Total Facial Restoration

BACKGROUND

Because of a lack of effective measures to visualize flap vasculature and perfusion, flap fenestration and facial organ fabrication cannot be performed effectively, preventing the transition from two-dimensional coverage to restoration of the three-dimensional (3D) structure of facial organs. This study aimed to evaluate the efficacy of indocyanine green angiography (ICGA) in guiding flap fenestration and facial organ fabrication in total facial restoration.

METHODS

Ten patients with total facial scarring after burn injury were enrolled in the study. They were treated with preexpanded, prefabricated monoblock flaps for total face restoration. The openings of nostrils and oral and palpebral orifices, together with organ fabrication, were conducted under the guidance of intraoperative ICGA by hemodynamic evaluation of flap perfusion. Postoperative follow-up measures include vascular crisis, infection, flap necrosis, and aesthetic and functional recovery.

RESULTS

The opening of facial organ orifices was performed at the stage of flap transfer in nine patients. To avoid damaging the major nourishing vessels, the left palpebral orifice was opened 8 days after the flap transfer in one patient, as observed by ICGA. Based on ICGA evaluation, the decision to perform additional vascular anastomosis before flap fenestration was made in six patients. Hemodynamic analysis of flap perfusion after fenestration revealed no significant change. Follow-up showed satisfactory aesthetic recovery and well-restored 3D structures of facial organs.

CONCLUSION

This pilot study demonstrates how intraoperative ICGA can enhance the safety of flap fenestration, thereby transforming full facial restoration from the two-dimensional to the 3D realm by facilitating facial organ fabrication.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Utilization of two methods assisting perforator identification for brachial artery perforator propeller flap application

The brachial artery perforator propeller (BAPP) flap has the advantages of both local and perforator propeller flaps, and it remains relatively underused partly because of the anatomical variations of perforators in the medial arm. We aimed to review our preliminary experience using two different methods for perforator localization of a BAPP flap, including the application of a refined coordinate system (the ABC system) in the medial arm and indocyanine green angiography (ICGA). We evaluated the advantages and disadvantages of these methods and selected the optimal examination mode depending on detailed clinical settings. The perforator was identified for each patient using the ABC system and/or ICGA, depending on the clinical setting. Twenty-two patients underwent soft-tissue reconstructions with 22 BAPP flaps, and perforator localization for all the flaps was performed before surgery using the ABC system. Thirty-one perforators were localized before surgery and marked accordingly, all of which were visualized during surgery, except two, which were not found during the surgery. ICGA was used in six pre-expanded flaps at both stages of surgeries. Twenty-seven perforators were detected before surgery, and all of them were identified during surgery; the previously localized perforators found using the ABC system in the six patients were all reidentified using ICGA. Both the ABC system and ICGA were found to be useful for preoperative perforator localization in BAPP flap transfers. Each method has its unique downsides; however, they can supplement each other to facilitate safe and effective flap elevation. Therefore, selection of the optimal method based on the clinical settings is recommended.

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.

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.

Role of Indocyanine Green Angiography in Free Flap Surgery: A Comparative Outcome Analysis of a Single-Center Large Series of 877 Consecutive Free Flaps

Purpose  This study aims to assess and validate the role and cost-effectiveness of indocyanine green angiography (ICGA) in free flap surgery outcomes. A new intraoperative protocol of whole-body surface warming (WBSW) for all free flap surgeries during the strategic "microbreaks" is also described. Methods  A retrospective analysis of 877 consecutive free flaps, performed over 12 years, is presented. The results of the ICGA group ( n  = 438) were compared with the historical No-ICGA group ( n  = 439), and statistical significance was calculated for three crucial flap-related adverse outcomes and cost-effectiveness. ICGA was also used as a tool to show the effect of WBSW on free flaps. Results  ICGA showed a notably strong statistical significance in decreasing two outcome parameters, namely, partial flap loss and re-exploration rate. It was also cost-effective. ICGA also demonstrated the positive role of WBSW in increasing flap perfusion. Conclusions  Our study shows that the usage of ICGA for intraoperative assessment of flap perfusion can significantly reduce the partial flap loss and re-exploration rate in free flap surgeries in a cost-effective manner. A new protocol of WBSW is also described and recommended to increase flap perfusion in all free flap surgeries.

[The conjoined latissimus dorsi and parascapular free flap for reconstruction of extensive soft tissue defects]

OBJECTIVE

Durable and resilient soft tissue reconstruction of vast defects of the extremities or the torso.

INDICATIONS

Reconstruction of disproportionately large defects, particularly in cases of simultaneous bone and joint reconstruction.

CONTRAINDICATIONS

History of surgery or irradiation of upper back and axilla, impossibility of surgery under lateral positioning; relative contraindications in wheelchair users, hemiplegics, or amputees.

SURGICAL TECHNIQUE

General anesthesia and lateral positioning. First, the parascapular flap is harvested, with the initial skin incision made medially in order to identify the medial triangular space and the circumflex scapular artery. Flap raising then proceeds from caudal to cranial. Second, the latissimus dorsi is harvested, with the lateral border being dissected free first, before the thoracodorsal vessels are visualized on its undersurface. Flap raising then proceeds from caudal to cranial. Third, the parascapular flap is advanced through the medial triangular space. If the circumflex scapular and thoracodorsal vessels originate separately from the subscapular axis, an in-flap anastomosis is warranted. Subsequent microvascular anastomoses should be performed outside the zone of injury, typically in an end-to-end fashion of the vein and end-to-side fashion of the artery.

POSTOPERATIVE MANAGEMENT

Postoperative anticoagulation with low-molecular-weight heparin under anti-Xa monitoring (semitherapeutic in normal-risk and therapeutic in high-risk cases). Hourly clinical assessment of flap perfusion for 5 consecutive days, followed by stepwise relaxation of immobilization and commencement of dangling procedures in cases of lower extremity reconstruction.

RESULTS

Between 2013 and 2018, 74 conjoined latissimus dorsi and parascapular flaps were transplanted to cover vast defects of the lower (n = 66) and upper extremity (n = 8). The mean defect size was 723 ± 482 cm² and the mean flap size was 635 ± 203 cm². Eight flaps required in-flap anastomoses for separate vascular origins. There was no case of total flap loss.

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.

[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.

A Comparison of Handheld Doppler and Indocyanine Green Angiography for Perforator Localization

BACKGROUND

The preoperative identification of perforators is critical to the success of perforator flaps. Several technologies, including handheld Doppler (HHD) and indocyanine green angiography (ICGA), facilitate this process; however, each technology comes with unique downsides. This study directly compares the performance of HHD and ICGA in preoperative perforator identification and measures the effects of flap thickness and body mass index (BMI) on perforator localization.

METHOD

Data from preoperative HHD and ICGA assessments were compared with the criterion standard of intraoperative perforator localization. Sensitivity, specificity, accuracy, and positive predictive values were calculated for both and correlated with flap thickness and BMI.

RESULTS

Thirty flaps were transferred in 30 patients across 15 different donor sites. Indocyanine green angiography had higher sensitivity, accuracy, and positive predictive value (79.2%, 74.2%, and 87.5%, respectively) than HHD (55.6%, 46.6%, and 69.4%, respectively). Perforators detected by ICGA were used as flap pedicles in 21 cases compared with 13 with HHD. There were no correlations between HHD or ICGA performance and patient BMI (both P > 0.05). Increasing flap thickness was negatively correlated with the accuracy of ICGA ( P = 0.001) but not HHD ( P > 0.05).

CONCLUSIONS

Indocyanine green angiography was more sensitive, specific, and accurate than HHD in identifying perforators across various donor sites; however, its performance suffered in thicker flaps, whereas HHD did not. Patient BMI was not correlated with the performance of either technology. Additional research can further delineate the interrelationships of flap thickness and technologies for perforator localization.

Combined versus Single Perforator Propeller Flaps for Reconstruction of Large Soft Tissue Defects: A Retrospective Clinical Study

Sufficient wound closure of large soft tissue defects remains a challenge for reconstructive surgeons. We aimed to investigate whether combined perforator propeller flaps (PPFs) are suitable to expand reconstructive options. Patients undergoing PPF reconstruction surgery between 2008 and 2021 were screened and evaluated retrospectively. Of 86 identified patients, 69 patients received one perforator propeller flap, while 17 patients underwent combined PPF reconstruction with multiple flaps. We chose major complications as our primary outcome and defined those as complications that required additional surgery. Postoperatively, 27 patients (31.4%) suffered major complications. The propeller flap size, the type of intervention as well as the operation time were not associated with a higher risk of major complications. A defect size larger than 100 cm², however, was identified as a significant risk factor for major complications among single PPFs but not among combined PPFs (OR: 2.82, 95% CI: 1.01−8.36; p = 0.05 vs. OR: 0.30, 95% CI: 0.02−3.37; p = 0.32). In conclusion, combined PPFs proved to be a reliable technique and should be preferred over single PPFs in the reconstruction of large soft tissue defects at the trunk and proximal lower extremity.

The Role of ICG Angiography in Decision Making About Skin-Sparing in Pediatric Acute Trauma

BACKGROUND

Indocyanine green (ICG) angiography has proven useful in assessing skin flap perfusion in plastic and reconstructive surgeries. This research aimed to explore its role in decision making about skin-sparing in children's acute trauma.

METHODS

A total of 19 patients suffering with acute trauma from January 2019 to September 2021 were retrospectively assessed. Both ICG angiography and clinical judgment were performed to evaluate skin tissue viability. The intraoperative decisions for each case depended on the specific condition of the traumatic wound, including tissue perfusion, skin defect area, and location of the wound. Postoperative vascular imaging software was used to quantify the tissue perfusion, and the duration of postoperative follow-up was from 6 to 18 months.

RESULTS

Among them, 18 (94.7%) patients experienced treatments according to ICG angiography and did not develop postoperative necrosis. One case with right forearm trauma suffered from partial necrosis. Hypertrophic scar and local infection were the independent complications, which were managed by symptomatic treatment.

CONCLUSION

ICG angiography may reduce the risk of postoperative necrosis and renders a promising adjunctive technique for surgeons to make reasonable decisions in skin sparing in acute pediatric trauma.

Hyperintensity of integrin-targeted fluorescence agent IntegriSense750 accurately predicts flap necrosis compared to Indocyanine green

BACKGROUND

Flap necrosis is a feared complication of reconstructive surgery. Current methods of prediction using Indocyanine green (ICG) lack specificity. IntegriSense750 is a fluorescence agent that binds sites of vascular remodeling. We hypothesized that IntegriSense750 better predicts flap compromise compared to ICG.

METHODS

Fifteen mice underwent lateral thoracic artery axial flap harvest. Mice received an injection of ICG (n = 7) or IntegriSense750 (n = 8) daily from postoperative days (POD) 0-3 and were imaged daily. Mean signal-to-background ratios quantified the change in fluorescence as necrosis progressed.

RESULTS

Mean signal-to-background ratio was significantly higher for IntegriSense750 compared to ICG on POD0 (1.47 ± 0.17 vs. 0.86 ± 0.21, p = 0.01) and daily through POD3 (2.12 ± 0.70 vs. 0.96 ± 0.29, p < 0.001).

CONCLUSIONS

IntegriSense750 demonstrates increased signal-to-background ratio at areas of flap distress compared to ICG which may increase identification of flap necrosis and improve patient outcomes.

Deep Inferior Epigastric Artery Perforator Flap Breast Reconstruction in the Setting of Cryolipolysis

The deep inferior epigastric artery perforator (DIEP) flap is a safe and reliable autologous breast reconstruction option for patients undergoing surgical treatment for breast cancer. Success of the procedure relies on adequate flap perfusion from perforators that travel within the subcutaneous layer of the abdominal wall. Patients who have undergone invasive abdominal wall procedures such as suction-assisted liposuction may therefore be at increased risk of postoperative complications such as flap loss and fat necrosis. In recent years, noninvasive fat-reduction techniques such as cryolipolysis have grown immensely in popularity. However, there are no data regarding outcomes for patients who have undergone DIEP flap breast reconstruction after having previously undergone abdominal cryolipolysis. The current case demonstrates that free flap breast reconstruction can be performed safely in this patient population, and that adjunct imaging modalities may improve clinical decision-making.

Comparison of Various Modalities Utilized for Preoperative Planning in Microsurgical Reconstructive Surgery

BACKGROUND

 The benefits of preoperative perforator imaging for microsurgical reconstruction have been well established in the literature.

METHODS

 An extensive literature review was performed to determine the most commonly used modalities, and their applicability, advantages and disadvantages.

RESULTS

 The review demonstrated varioius findings including decreases in operative time and cost with the use of CT angiography to identification of perforators for inclusion in flap design with hand-held Doppler ultrasound. Modalities like MR angiography offer alternatives for patients with contrast allergies or renal dysfunction while maintaining a high level of clarity and fidelity. Although the use of conventional angiography has decreased due to the availability of less invasive alternatives, it continues to serve a role in the preoperative evaluation of patients for lower extremity reconstruction. Duplex ultrasonography has been of great interest recently as an inexpensive, risk free, and extraordinarily accurate diagnostic tool. Emerging technologies such as indocyanine green fluorescence angiography and dynamic infrared thermography provide real-time information about tissue vascularity and perfusion without requiring radiation exposure.

CONCLUSION

 This article presents an in-depth review of the various imaging modalities available to reconstructive surgeons and includes hand held Doppler ultrasound, CT angiography, MR angiography, conventional angiography, duplex ultrasonography, Indocyanine Green Fluorescence Angiography and Dynamic Infrared Thermography.

Intra- and Extrathoracic Malignant Tracheoesophageal Fistula-A Differentiated Reconstructive Algorithm

BACKGROUND

Tracheoesophageal fistulae (TEF) after oncologic resections and multimodal treatment are life-threatening and surgically challenging. Radiation and prior procedures hamper wound healing and lead to high complication rates. We present an interdisciplinary algorithm for the treatment of TEF derived from the therapy of consecutive patients.

PATIENTS AND METHODS

18 patients (3 females, 15 males) treated for TEF from January 2015 to July 2017 were included. Two patients were treated palliatively, whereas reconstructions were attempted in 16 cases undergoing 24 procedures. Discontinuity resection and secondary gastric pull-up were performed in two patients. Pedicled reconstructions were pectoralis major (n = 2), sternocleidomastoid muscle (n = 2), latissimus dorsi (n = 1) or intercostal muscle (ICM, n = 7) flaps. Free flaps were anterolateral thigh (ALT, n = 4), combined anterolateral thigh/anteromedial thigh (ALT/AMT, n = 1), jejunum (n = 3) or combined ALT-jejunum flaps (n = 2).

RESULTS

Regarding all 18 patients, 11 of 16 reconstructive attempts were primarily successful (61%), whereas long-term success after multiple procedures was possible in 83% (n = 15). The 30-day survival was 89%. Derived from the experience, patients were divided into three subgroups (extrathoracic, cervicothoracic, intrathroracic TEF) and a treatment algorithm was developed. Primary reconstructions for extra- and cervicothoracic TEF were pedicled flaps, whereas free flaps were used in recurrent or persistent cases. Pedicled ICM flaps were mostly used for intrathoracic TEF.

CONCLUSION

TEF after multimodal tumor treatment require concerted interdisciplinary efforts for successful reconstruction. We describe a differentiated reconstructive approach including multiple reconstructive techniques from pedicled to chimeric ALT/jejunum flaps. Hereby, successful reconstructions are mostly possible. However, disease and patient-specific morbidity has to be anticipated and requires further interdisciplinary management.

A Retrospective Comparative Functional and Aesthetic Outcome Study of Muscle versus Cutaneous Free Flaps for Distal Upper Extremity Reconstruction

BACKGROUND

 Function and cosmesis are crucial in upper extremity reconstruction. Yet, there persists a lack of outcome evaluations, particularly regarding differences between free flap types.

METHODS

 In a single-center retrospective analysis, outcomes were compared between patients with cutaneous or muscle free flaps for distal upper extremity reconstruction between 2008 and 2018. The Disabilities of Arm, Shoulder and Hand -Score, Michigan-Hand (MHQ), and Short Form 36 Health Survey (SF-36) Questionnaires were assessed, motor function was quantified, and self-reported measures of cosmesis were compared, including the Vancouver Scar-Scale (VSS), MHQ aesthetics-subscale (MAS), and Moscona's cosmetic validation-score (CVS).

RESULTS

 One-hundred forty-one cases were identified, with a shift toward cutaneous flaps over the study period. Muscle flaps were used for larger defects (251 vs. 142 cm², p = 0.008). Losses, thromboses, and donor-site complications were equally distributed. Partial necroses were more frequent in muscle flaps (11 vs. 1%, p = 0.015). Seventy patients with 53 cutaneous versus 17 muscle flaps were reexamined. There was no difference in the timing of flap coverage (after 16 vs. 15 days, p = 0.79), number of preceding (2 vs. 1.7, p = 0.95), or subsequent operations (19/53 vs. 5/17, p = 0.77). Patients with cutaneous flaps showed higher grip strength (25 vs. 17 kg, p = 0.046) and reported better hand function (MHQ: 58 vs. 47, p = 0.044) and general health (SF-36: 70 vs. 61, p = 0.040), as well as more favorable appearance (MAS: 71 vs. 57, p = 0.044, CVS: 77 vs. 72, p = 0.048), and scar burden (VSS: 0 vs. 3, p < 0.001).

CONCLUSION

 Cutaneous flaps yielded better motor function, self-perceived cosmesis, patient satisfaction, and quality of life in our cohort of distal upper extremity reconstructions.

Use of Indocyanine Green Angiography for Real-Time Assessment of a Sternocleidomastoid Muscle Flap During Complex Facial Reconstruction

Indocyanine green (ICG) angiography is a procedure that uses a fluorescent dye for a variety of medical diagnostics, including the real-time examination of blood flow in tissue. Herein, we report a case in which ICG angiography was used to assess the viability of a sternocleidomastoid (SCM) muscle flap during post-parotidectomy facial reconstruction. To our knowledge, this is the first report documenting the intraoperative use of ICG for the evaluation of SCM flap perfusion. ICG angiography may prove beneficial for cases involving complex reconstructions and suspected organ hypoperfusion.

The Use of Indocyanine Green Angiography for Cosmetic and Reconstructive Assessment in the Head and Neck

Reconstructive procedures in the head and neck can be a surgical challenge owing to the complex anatomical and physiological structure. Different locoregional and microvascular flaps are used for various defects to improve both function and cosmesis. Subjective clinical findings have been the mainstay for perfusion monitoring; however, areas of borderline perfusion are much more difficult to assess clinically. Multiple technologies that offer objective perfusion assessment have been developed to improve surgical outcomes. Indocyanine green (ICG) angiography has gained popularity owing to its minimal invasiveness and increased sensitivity and specificity in assessing flap perfusion particularly in the head and neck. It has been extensively used in free flaps, pedicled flaps (including nasal reconstruction), facelift procedures, random flaps, skull base reconstruction, and pharyngocutaneous fistula prediction. Its perioperative use has provided valuable qualitative and quantitative data that aid our understanding of flap hemodynamics. Clinically, this impacted decision-making in flap design, harvest, inset, and precocious salvage interventions. Though increased cost and intraoperative time could be limitations, cost-effectiveness studies have supported its use, particularly in high-risk individuals. Limitations include the lack of standardized dosing and consistent methodology agreement for data analysis. Future studies should involve larger cohorts and multi-institute studies to overcome such limitations.

A Structured, Microsurgical Training Curriculum Improves the Outcome in Lower Extremity Reconstruction Free Flap Residency Training: The Ludwigshafen Concept

BACKGROUND

 Risk stratification, economic pressure, and a flat learning curve make the realization and development of proper microsurgical skills and competences a challenging task in the daily clinical practice. In previous studies, we were able to show that microsurgical procedures, e.g., free flaps and replantations, are safe training procedures and teachable in daily clinical practice in view of certain issues of risk stratification. The present study aims to evaluate further improvements in terms of safety and complication rates for free flaps as a training procedure after introduction and continuous implementation of a structured in-house training curriculum for microsurgical skills and competences and a 24-hour free accessible microsurgical training facility for the plastic surgery resident.

METHODS

 This retrospective comparative cohort study was conducted to review whether microsurgical skills for free flaps to the lower extremity can further be improved after implementation of the curriculum and a 24-hour accessible training facility. Therefore, we compared cohort A before (2009-2012) and B after (2014-2017) implementation. Patient demographics, procedural characteristics, and outcome parameters for free tissue transfer of the lower extremity were evaluated.

RESULTS

 The comparison of both cohorts showed a significantly reduced postoperative complication rate for cohort B (p <0.05). Furthermore, operation time was shorter, and the hospital stay could be significantly decreased (p <0.01). Workhorse flaps for plastic surgical training were the anterior lateral thigh (ALT) flap or the musculus latissimus dorsi (LD) flap. However, even more complex procedures with arteriovenous loops could be safely performed by plastic surgery residents under the supervision of the senior surgeon in exceptional cases.

CONCLUSION

 The implementation of a regularly held, microsurgical in-house training curriculum with 24-hour accessible training facility improves procedural and outcome parameters for free flaps to the lower extremity for surgical residents and is an elementary part of skills and competency training. However, risk stratification, repeated surgical exposure, expertise, and institutional infrastructures are essential and must be taken into consideration.