Anatomical features of a crossing vein connecting left and right internal mammary veins: A preliminary study with computerized tomography or magnetic resonance imaging.

BACKGROUND: In breast reconstruction with free flaps, retrograde venous anastomosis into the internal mammary vein (IMV) is often unavoidable. Utility of a crossing vein between the right and left IMV, one of the anatomical foundations which make retrograde flow possible, has been reported but only with a few detailed features. This study evaluated the presence, actual location, and diameter of the crossing veins using preoperative imaging such as contrast-enhanced computed tomography (CECT), or contrast-enhanced magnetic resonance imaging (CEMRI). Moreover, this is a preliminary non-invasive study to clarify these processes on a larger scale. METHODS: We included 29 cases of unilateral breast reconstruction performed between July 2018 and September 2023 at our institution using unipedicled or bipedicled free deep inferior epigastric artery perforator (DIEP) flaps with retrograde venous anastomosis to only one IMV at the level of anastomosis. No congestion or necrosis was observed. In the final 24 cases with sufficient imaging coverage of preoperative contrast-enhanced images (15 CECT and 9 CEMRI), the crossing veins of IMVs were detected and the number, localization, and diameter were measured. RESULTS: In 20 cases of 24 images, the crossing veins between IMVs were completely identified (83%). In 18 of the cases, only one crossing vein was established immediately ventral to the xiphoid process, averaging 19.3 ± 7.18 mm caudal to the fibrous junction between the sternal body and xiphoid process. The average diameter of the veins was 1.57 ± 0.42 mm. In two other cases, the second crossing vein originated on the dorsal surface of the sternum, but it was a very thin vein of about 0.4 mm. Three images indicated incomplete identification of the crossing vein at the xiphoid process, and in one case, no crossing vein was observed between bilateral IMVs. CONCLUSION: The contrast-enhanced imaging study revealed an anatomic feature that the crossing veins (about 1.5 mm in diameter) connecting the right and left IMVs are located just ventral to the xiphoid process. Furthermore, the crossing veins can be identified on contrast-enhanced images, and refinement of this method is expected to lead to future non-invasive anatomical investigations in an even larger number of cases.

The study of DIEA three dimensional reconstruction technique based on CTA in preoperative perforator selection.

Preoperative selection of perforator is one of the key steps for successful surgery. The purpose of this study is to simulate the selection process of the perforator of the flap using the 3D models of the deep inferior epigastric artery (DIEA). A retrospective study was performed of women who underwent deep inferior epigastric perforator flap breast reconstruction from January 2011 to July 2021. Construct 3D models of the DIEA using computerized tomography angiography images, and then computational fluid dynamics simulations were performed. Correlation and regression analyses were used to analyze the geometric and hemodynamic parameters. Statistical analysis suggested that the outlet flow was positively correlated with the inlet area (r = 0.338, p = 0.000), outlet area (r = 0.840, p = 0.000), the average radius of the perforator (r = 0.592, p = 0.000), and negatively correlated with the length of perforator(r = -0.210, p = 0.024). The results of linear regression analysis showed that the outlet area (p = 0.000), the average radius (p = 0.000), and the length (p = 0.044) of the perforator were the influencing factors on outlet flow. In multiple perforators analysis, there was a significant difference in the total outlet flow among single perforator, double perforators, and triple perforators (p = 0.002). The successful implementation of this experiment provides a new approach for the selection of dominant perforators in the future.

Preoperative Imaging Mapping of DIEP Perforators and Intraoperative Selection: Does It Correlate?

BACKGROUND: Preoperative imaging prior to deep inferior epigastric perforator (DIEP) flap harvest is a common practice to locate perforators and identify aberrant anatomy. METHODS: We report a retrospective review of 320 consecutive patients who underwent preoperative computed tomographic angiography (CTA) or magnetic resonance angiography prior to DIEP flap breast reconstruction. The locations relative to the umbilicus of preoperatively identified perforators were compared with the selected intraoperative perforators. The diameter of all intraoperative perforators was also measured. RESULTS: Across the 320 patient, 1,833 potentially suitable perforators were identified on preoperative imaging. A total of 564 of the 795 perforators selected intraoperatively for DIEP flap harvest were within 2 cm of a predicted perforator, for a rate of 70.1%. The size of the perforator was unrelated to the detection rate. CONCLUSION: We were able to demonstrate a sensitivity of 70% of clinically selected DIEP perforators identified on preoperative imaging in this large series. This contrasts with the nearly 100% predictive value reported by others. Continued reporting of findings and methods of measuring are needed to improve the practical efficacy of CTA and raise awareness about the limitations of CTA, despite its well-documented usefulness.

Preoperative planning using virtual reality and computed tomography angiogram in deep inferior epigastric perforator flap breast reconstruction.

The gold standard for preoperative planning of deep inferior epigastric perforator (DIEP) flap breast reconstruction uses computed tomography angiography (CTA). Virtual reality (VR) circumnavigates the limitations of CTA by reconstructing a fully immersive and interactive 3D representation of the scan. Scans of 44 patients who underwent DIEP flap breast reconstruction were retrospectively reviewed and compared using CTA and VR imaging modalities. The objective of this research was to compare perforators found using VR to the ones identified using conventional CTA. A correlation was found between the imaging modalities for unilateral (R = 0.96 (CI = 0.92, 0.98)) and bilateral (R = 0.93, (CI = 0.83, 0.97)) DIEP flap surgeries when comparing perforator location related to the umbilicus. Multivariable ordinal logistic regression found that higher intramuscular course length (IMC) is associated with the number of perforators found per side (OR = 1.79 (CI = 1.24, 2.6)), and medial location (OR = 2.85 (CI = 1.38, 5.87)). Larger vessel caliber (VC) is associated with shorter IMC (T2 vs. T3, OR = 3.34 (CI = 1.49, 7.49)), and branching in adipose tissue (AB) is associated with higher VC (T1 vs. T3, OR = 0.02 (CI = 0.007, 0.08); T2 vs. T3, OR = 0.24 (CI = 0.11, 0.55)). Overall, preoperative planning using VR was easy to use, safe, more intuitive, and provided in a time-efficient manner, more information about perforant characteristics. VR can improve the surgeon's decision accuracy, relating to the best perforators for harvesting, in a shorter time period.

Ultrasonographic assessment of rectus abdominis muscle adaptation after deep inferior epigastric artery perforator (DIEP) flap surgery: Single institution retrospective study.

The impact of deep inferior epigastric artery perforator (DIEP) flap on abdominal wall integrity has been the topic of an ongoing debate with previous studies having reported conflicting results using various imaging modalities. Ultrasonography is a noninvasive, cost-effective, and readily available method for evaluating the changes to the rectus muscle after DIEP flap surgery. In the present study, we aimed to compare rectus abdominis muscle thickness between the operated and non-operated sides using ultrasound imaging. The muscle thickness was measured at the cross point of the midclavicular line and the level of the umbilicus and anterior superior iliac spine using real-time B-mode ultrasonography. The muscle anteroposterior diameters of the pedicle-dissected side and the control side were compared using paired t test. In total 31 patients with a mean follow-up of 70.18 weeks were included. The mean diameters at the level of the umbilicus of the operated and non-operated sides were 8.16 ±â€…1.83 and 8.14 ±â€…1.43 mm, respectively (P = .94). The mean thicknesses at the anterior superior iliac spine level were 7.74 ±â€…1.85 on the flap harvested side and 8.04 ±â€…1.84 mm on the control side (P = .35). There was no statistically significant difference between the 2 groups. Ultrasonography can be a reliable, inexpensive, and easily usable modality for evaluating donor site complication following DIEP flap. DIEP flap seems to have minimal impact on the abdominal donor site, and it may be safe and versatile to reconstruct the breast after mastectomy.

Color Doppler ultrasound versus CT angiography for DIEP flap planning: A randomized controlled trial.

BACKGROUND: Identifying relevant perforators is crucial in planning a deep inferior epigastric perforator (DIEP) flap. Color Doppler ultrasonography (CDU) has gained popularity for localizing perforators; however, current evidence on its efficiency is still inconclusive. This study aimed to compare the efficiency of CDU with that of computed tomography angiography (CTA) in localizing and selecting the relevant perforators. METHODS: In this randomized controlled trial, 60 patients undergoing DIEP flap breast reconstruction (uni- or bilateral) were randomly assigned to the CDU group (i.e., CDU was performed to map and select the relevant perforators preoperatively) or the CTA+CDU group (i.e., mapping was based on CTA and supplemented by CDU). CDU was performed by the same surgeon with a well-defined sonography experience from our previous study. The reference XY coordinates of the dissected perforators were measured intraoperatively, and deviations from preoperatively deducted coordinates were calculated (ΔCDU or ΔCTA+CDU). The flaps were categorized according to the number of dissected perforators, and adherence to the preoperative strategy was evaluated. RESULTS: Overall, 22 patients (30 flaps) in the CTA+CDU group and 27 (39 flaps) patients in the CDU group were evaluated. The average ΔCDU (0.6 cm) was significantly lower than the average ΔCTA+CDU (1.0 cm) (p < 0.001). Adherence to the mapping-based dissection strategy was higher in the CDU group; however, the difference was insignificant (p = 0.092). CONCLUSION: CDU is not inferior to CTA + CDU in localizing and selecting relevant DIEA perforators. Therefore, CDU mapping is a possible complementary or substitute modality for CTA mapping.

Efficacy of superficial inferior epigastric vein superdrainage in free TRAM and DIEP flap: An indocyanine green angiography study of 68 cases.

BACKGROUND: This study aimed to evaluate the clinical efficacy of venous augmentation using superficial inferior epigastric vein (SIEV) in free transverse rectus abdominis musculocutaneous (TRAM) and deep inferior epigastric artery perforator (DIEP) flap and investigate the factors that hinder the venous superdrainage. METHODS: A retrospective review of 62 free muscle-sparing (MS)-TRAM and 6 DIEP unilateral breast reconstructions from September 2017 to July 2022. Intraoperative indocyanine green angiography was performed on the harvested flap, with the SIEV contralateral to the pedicle side clamped and unclamped for 20 min. The relative ratio of hypoperfused area to the total flap area was calculated and compared quantitatively. The preoperative computed tomography (CT) angiography was reviewed to obtain information on the SIEV diameter and number of midline-crossing medial branches. RESULTS: The participants were categorized into three groups: 42 patients in Group 1 (>3% decrease in hypoperfused area), 20 patients in Group 2 (change in hypoperfused area ranging from -3% to 3%), and six patients in Group 3 (>3% increase in hypoperfused area). The mean number of midline-crossing branches (p = 0.002) and mean difference in the diameter of bilateral SIEVs (p = 0.039) were significantly greater in Group 1 than in the other groups. CONCLUSIONS: Thirty-eight percent (26/68 cases) resulted in sustained or aggravated perfusion after SIEV superdrainage. Superdrainage using the contralateral SIEV in free MS-TRAM/DIEP flap is recommended when there are more than two midline-crossing medial branches of SIEV and when the caliber of SIEV is relatively greater compared with the pedicle side.

Preoperative visualization of midline-crossing subcutaneous arteries in transverse abdominal flaps using photoacoustic tomography.

BACKGROUND: Photoacoustic tomography is a noninvasive vascular imaging modality that uses near-infrared pulsed laser light and ultrasound to visualize vessels. We previously demonstrated the utility of photoacoustic tomography for anterolateral thigh flap surgery involving body-attachable vascular mapping sheets. However, it was not possible to obtain clear separate images of arteries and veins. In this study, we tried to visualize subcutaneous arteries that cross the midline of the abdomen, since these arteries are known to be important for obtaining large perfusion areas in transverse abdominal flaps. METHODS: Four patients scheduled to undergo breast reconstruction with abdominal flaps were examined. Photoacoustic tomography was performed preoperatively. The tentative arteries and veins were traced according to the S-factor, an approximate hemoglobin oxygen saturation parameter calculated using 2 laser excitation wavelengths (756 and 797 nm). Intraoperatively, arterial-phase indocyanine green (ICG) angiography was performed after abdominal flap elevation. Images of vessels speculated to be arteries by preoperative photoacoustic tomography were merged with those of intraoperative ICG angiography and analyzed in an 8 × 4-cm2 area below the umbilical region. RESULTS: The S-factor was used to visualize the midline-crossing subcutaneous arteries in all 4 patients. A matching analysis compared preoperative tentative arteries according to photoacoustic tomography with ICG angiography results in the 8 × 4-cm2 area below the umbilical region and indicated a 71.3-82.1% match (average: 76.9% match). CONCLUSIONS: This study demonstrates that the S-factor, a noninvasive, label-free imaging modality, can be used to successfully visualize subcutaneous arteries. This information can aid in selecting perforators for abdominal flap surgery.

HoloLens in Breast Reconstruction: What Is the Future?

SUMMARY: Autologous breast reconstruction using the deep inferior epigastric perforator flap has been established as the standard for perforator-based free-flap breast reconstruction. This technique relies on the surgeon's ability to identify the patient's relevant abdominal vasculature to facilitate accurate dissection, optimize surgical outcomes, and minimize morbidity. A technique is described in which the authors incorporate augmented reality using HoloLens technology in their surgical planning to identify epigastric arteries and perforators. This technology allows the surgeon to superimpose computed tomography angiography images directly onto the patient, facilitating an in vivo appreciation of underlying anatomy before incision and dissection. This allows real-time surgical planning, increasing the value and tangibility of preoperative computed tomography angiography with the potential to enhance the accuracy and efficiency of the operative technique. Although the authors did not use the HoloLens technology to make clinical decisions, they provide evidence of its accuracy and ease of use, offering a proof of concept. The potential of this technology is demonstrated, and the authors encourage future application in free-flap breast reconstruction and beyond.

Three-dimensional Volume Changes of the Reconstructed Breast Following DIEP Flap Breast Reconstruction.

BACKGROUND: This study aimed to assess whether the reconstructed breast volume changed postoperatively following a deep inferior epigastric artery perforator (DIEP) flap. METHODS: Patients were included if they had undergone unilateral breast reconstruction with a DIEP flap at the two selected centers between April 2017 and September 2019. Serial 3-D surface imaging of both breasts was taken at 1, 3, 6, and 12 months postoperatively. The primary outcome was a volume ratio of the reconstructed to the contralateral breast. A linear mixed-effect model was used to evaluate whether the DIEP flap volume changed according to the postoperative time. RESULTS: A total of 74 patients were included in the analysis. The mean volume ratio of the reconstructed side compared with the contralateral breast at 1, 3, 6, and 12 months postoperatively were 106.9%, 105.9%, 108.7%, and 107.6%, respectively. In the linear mixed effect model, the volume ratio of the reconstructed breast did not change over time for immediate reconstructions (p = 0.376). However, there was an increase over time in delayed reconstructions (p = 0.043). Adjuvant radiation, chemotherapy, and hormone therapy did not influence the volume ratio of the reconstruced breast. Correlation analysis using repeatedly measured values showed that both reconstruced and healthy breast volumes had positive correlation with the patient's body weight (p < 0.001). On the other hand, volume ratio of the breasts was not influenced by the patient's body weight (p = 0.493). The volume ratio of the reconstructed breast significantly decreased in the upper inner (p = 0.003) and the upper outer (p = 0.006) quadrants, while increasing in the lower outer (p = 0.002) quadrant throughout the first-year postoperative period. CONCLUSION: The volume ratio of the reconstructed to the contralateral breast does not decrease postoperatively following DIEP flap breast reconstruction.

Anatomical characteristics of the inferior epigastric artery in Uygur and it's implication in the management of bleeding.

OBJECTIVES: This study aimed to determine the locations of the inferior epigastric arteries in a group of Uygur by ultrasound and explore the anatomical characteristics of vessels in the management of inferior epigastric bleeding. METHODS: The study included 61 patients. The locations of inferior epigastric arteries through ultrasound were determined at three levels, and the distance from the midline was correlated with patients' demographics by Pearson correlation coefficient. RESULTS: This study included 52 males and nine females, with a mean age of 37.56 years (± SD 3.16) and a mean BMI of 24.34 kg/m2 (± SD 3.71). At the symphysis pubis level, the average distance from the inferior epigastric artery to the midline was 5.98 ± 0.13 cm on the right and 7.32 ± 0.15 cm on the left. At the anterior superior iliac spine level, the average distance of the inferior epigastric artery on the right was 4.12 ± 0.15 cm and 5.2 ± 0.15 cm on the left. The inferior epigastric arteries were 3.86 ± 0.17 cm on the right and 5.06 ± 0.16 cm on the left of the midline at the level midway between the umbilicus and anterior superior iliac spine. CONCLUSION: Inferior epigastric arteries were located between 3.5 and 8 cm from the midline, with the right vessel being closer to the midline than the left. The invasive operations through the abdominal wall should avoid these areas to reduce vascular injury. The anatomical characteristics of inferior epigastric arteries may potentially manage inferior epigastric bleeding.

Surgeon-conducted color Doppler ultrasound deep inferior epigastric artery perforator mapping: A cohort study and learning curve assessment.

BACKGROUND: Perforator mapping using diagnostic methods facilitates deep inferior epigastric perforator (DIEP) flap planning. Computed tomographic angiography (CTA) is a well-proven tool for perforator mapping. However, the benefits of color Doppler ultrasonography (CDU) are as follows: 1) CDU involves dynamic real-time examination and 2) does not use radiation. Comparing the accuracies of both methods in a cohort of patients, this study aimed to evaluate the learning curve of surgeon-conducted CDU perforator mapping. METHODS: Twenty patients undergoing DIEP flap breast reconstruction were enrolled in a cohort study. All patients underwent CTA perforator mapping preoperatively. XY coordinates of significant perforators were subtracted by a radiologist. A single surgeon (sonographer) with minimal experience with CDU performed CDU perforator mapping, including XY coordinates subtraction. The sonographer was blinded to the CTA data. The reference coordinates of dissected perforators were measured during surgery. Deviations from reference coordinates for both methods were compared, and CDU mapping learning curve was assessed using Joinpoint Regression. RESULTS: We included 20 women (32 DIEP flaps and 59 dissected perforators). The mean deviation between mapped and reference coordinates was 1.00 (0.50-1.12) cm for CDU and 0.71 (0.50-1.12) cm for CTA. The learning curve of CDU mapping showed the breaking point after the seventh patient (≈ 21 localized perforators). After the breaking point, no significant differences between the deviations of both methods were found (p = 0.980). CONCLUSION: A limited number of examinations were needed for the surgeon to learn CDU DIEA perforator mapping with accuracy similar to that of CTA mapping.

ACR Appropriateness Criteria® Imaging of Deep Inferior Epigastric Arteries for Surgical Planning (Breast Reconstruction Surgery): 2022 Update.

Breast cancer is the most common malignancy in women in the United States, with surgical options including lumpectomy and mastectomy followed by breast reconstruction. Deep inferior epigastric perforator (DIEP) flap is a muscle-sparing perforator free flap breast reconstruction technique, which uses the deep inferior epigastric artery (DIEA) perforators to create a vascular pedicle. Multiple perforators are identified by preoperative imaging, which are typically ranked based on size, location, and intramuscular course. The goal of preoperative imaging is to aid the surgical team in preoperative planning given the variability of the DIEA perforator branches anatomy between patients. The objective of this document is to review the imaging modalities that can be used preoperatively to identify the optimal perforator and thereby reduce intraoperative complications, reduce postoperative complications, and improve clinical outcomes. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Deep inferior epigastric perforator flap preoperative planning: A comparative analysis between dynamic infrared thermography, computerized tomography angiography, and hand-held Doppler.

INTRODUCTION: Hand-held Doppler (HHD) sonography and computerized tomography angiography (CTA) are the common assessment tools for deep inferior epigastric perforator (DIEP) flap preoperative planning. CTA is considered the gold standard method for preoperative perforator mapping but necessitates contrast medium and X-ray exposure. Dynamic infrared thermography (DIRT) does not have these drawbacks and allows the detection of hot and cold spots on a given body area. Our study aimed to compare DIRT, HHD, and CTA in perforator mapping for breast reconstruction using DIEP flap. PATIENTS AND METHODS: From March to September 2020, 12 consecutive patients scheduled for DIEP flap breast reconstruction were preoperatively investigated with HHD, CTA, and DIRT. The patients' mean age was 53 and the mean BMI was 29.23 kg/m2 . All the reconstructions were due to breast cancer. The results of preoperative perforator mapping on the lower abdomen were compared among the three techniques. All the evidence was compared to the intraoperative findings, during flap harvesting, to establish if the techniques were able to correctly locate the perforator. RESULTS: We detected 178 perforators intraoperatively, 178 with CTA, 178 with DIRT, and 125 with HHD. The latter revealed a lower number of perforator vessels for each patient (10.42 ± 3.58), compared with CTA (14.83 ± 3.04) and DIRT (14.83 ± 4.76). DIRT resulted superior to HHD (p < .05), while no statistically significant difference (p > .05) was found between DIRT and CTA. We calculated a mean sensitivity of 93.87% for CTA, 69.02% for HHD, and 92.06% for DIRT. CONCLUSION: DIRT is a useful tool in the preoperative planning of DIEP flaps, as it provides information about the location of perforators and the hemodynamic properties of angiosomes. It is easy to use, and it does not involve ionizing radiation. DIRT could represent an innovative and promising implementation of CTA and HHD techniques for preoperative perforator mapping in DIEP breast reconstruction.

Delineating the risk factors of venous congestion: An analysis of 455 deep inferior epigastric perforator flaps with radiographic correlation.

BACKGROUND: Venous congestion occurs in 2-15% of DIEP flaps for breast reconstruction. We previously showed that thicker suprascarpal fat pads are associated with increased SIEV caliber and may, by extension, indicate a dominant superficial venous system. In this study, we aim to provide clinical correlation and to determine the risk factors of venous congestion in order to identify high-risk patients who may benefit from prophylactic SIEV dissection. METHODS: An IRB-approved retrospective study was performed in patients who underwent DIEP flap reconstruction from August 2011 to August 2020. Radiographic measurements of suprascarpal fat pad thickness and SIEV diameter were collected per hemi-abdomen from preoperative imaging. The statistical analysis explored whether certain variables were associated with venous congestion. RESULTS: A total of 258 patients underwent 455 DIEP flaps. Suprascarpal fat pad thickness was positively correlated with SIEV diameter (r = 0.51, p<0.001), each with a mean caliber of 19.8 mm and 2.5 mm, respectively. Seven flaps (1.5%) developed venous congestion, with five requiring SIEV salvage and secondary venous anastomosis. Congested flaps had significantly thinner suprascarpal fat pads (12.3 vs. 20.0 mm, p = 0.043). All six congested flaps with imaging had suprascarpal thickness less than 18 mm, compared to 182 out of 335 non-congested flaps with imaging (p = 0.035). CONCLUSIONS: The risk of venous congestion following DIEP flap reconstruction is significantly increased with thinner suprascarpal fat pads, suggesting that the mechanism of venous congestion may not be limited to superficial venous dominance. We recommend prophylactic SIEV dissection in all patients with suprascarpal fat pad thickness less than 18 mm.

Matching the perforating branch of the internal thoracic artery and the deep inferior epigastric artery for breast reconstruction using multi-detector row computed tomography.

PURPOSE: Matching the diameter of the deep inferior epigastric artery (DIEA) and perforating branch (PB) of the internal thoracic artery (ITA) is important for arterial anastomosis during breast reconstruction using the DIEA flap. An anatomic investigation of these arteries was performed using multidetector row computed tomography (MDCT). PATIENTS AND METHODS: Contrast-enhanced MDCT data of 50 women (aged 18-90 years) covering the neck to the groin were analyzed. The diameter of the PBs of the ITA at their origins from the first to the sixth intercostal space and of the DIEA 20 mm from the bifurcation of the external iliac artery were measured. RESULTS: The mean diameters of the right and left DIEAs were 1.53 ± 0.263 mm and 1.53 ± 0.306 mm, respectively. The diameter of the PBs in the second and third intercoastal spaces was the same as the diameter of the DIEA, bilaterally. CONCLUSION: It is suggested that anastomosis of the DIEA with PBs of the ITA in the second and third intercoastal spaces is optimal for DIEA flap grafting. Our results could contribute to making vascular anastomosis easier, thereby reducing the burden on both surgeons and patients.

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

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