Leaving the perfusion zones? Individualized flap design in 100 free DIEP and ms-TRAM flaps for autologous breast reconstruction using indocyanine green angiography

Technique and Expected Benefit of Intraoperative Perfusion Imaging of Peripheral Nerves

Peripheral nerve surgery, particularly in cases of nerve compression syndrome (NCS), necessitates a comprehensive evaluation of intraneural blood flow, as localized reductions in nerve perfusion are integral to the etiopathogenesis of such conditions. Although nerve perfusion is currently guided by morphologic characteristics, this assessment is subjective and prone to bias. Intraoperative fluorescence-assisted perfusion imaging with indocyanine green (ICG) is an established tool in flap and lymphatic surgery to objectively assess perfusion intraoperatively. However, only a few unspecific applications of ICG in peripheral nerve surgery have been published so far. In this study, we performed intraoperative perfusion imaging using ICG in 16 consecutive operations within the peripheral nervous system, including microsurgical reconstructions after obstetric brachial plexus injury, decompression for NCS, and vascularized ulnar nerve interposition transfers. Our findings show the utility of ICG in delineating healthy perfusion borders at proximal and distal stump levels after neuroma resection, and we demonstrate a correlation between histological findings and these clinically observed perfusion patterns. In NCS cases, we demonstrate that ICG imaging is effective in highlighting reduced perfusion predecompression and improved perfusion postdecompression. Additionally, ICG proved valuable for assessing perfusion of free vascularized nerve grafts. Intraoperative ICG perfusion imaging is a valuable tool during surgery of the peripheral nervous system, providing insights into the etiopathogenesis of NCS and aiding in the visualization of perfusion. This study underscores the potential of ICG in nerve surgery and its applicability for improving surgical outcomes and advancing our understanding of peripheral nerve pathologies.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Application of Near Infrared Spectroscopy to Enhance Safety and Individualize Distraction of Severely Contracted Joints in Far-Advanced Dupuytren's Disease

Background: Slow distraction of contracted joints is a well-established treatment in far-advanced stages of Dupuytren's disease (DD). To assess finger perfusion and avoid malperfusion, we studied near infrared spectroscopy (NIRS) to evaluate the maximum extent of distraction that would not harm microcirculation to the finger. This technique also allows an optimized treatment in accordance with sufficient blood perfusion during distraction. Methods: Eligible patients with stage IV finger contractures who needed treatment for Dupuytren's contracture were included and prospectively investigated. The operation was performed with local anaesthesia. First, the Dupuytren strand of the treated finger was dissected in the palm to allow distraction. Under X-ray control, the distraction device was applied. Then, slow distraction of the treated joint was performed to evaluate the finger perfusion. To assess perfusion of the treated finger, NIRS was used to measure tissue oxygen saturation. If impaired finger perfusion was detected, traction was reduced until sufficient oxygen levels and perfusion patterns were reestablished. Results: NIRS was performed after application of the distraction device in seven cases. We treated six male and one female patient (mean age 70 years, range 51-80 years). Rapid distraction resulted in malperfusion of the treated fingers. Using NIRS proved to render reliable and reproducible information on finger perfusion and oxygenation in all seven patients. Conclusions: Application of NIRS enhances safety in the treatment of far-advanced DD finger contractures with an external skeletal distraction device. It is non-invasive, reproducible, easy to use and allows for an individualized adapted distraction velocity.

Perfusion Dynamics during Secondary Flap Debulking with Liposuction

BACKGROUND

 Lower extremity trauma often necessitates reconstruction with flap transfer. One of the reconstructive goals is a thin soft tissue coverage with appropriate contour. Therefore, a secondary debulking of the flap is usually performed.

METHODS

 Debulking through conventional lipectomy is compared with liposuction followed by excision of the defatted flap excess. Demographic data, surgical details, and postoperative outcomes are compared and analyzed. The perfusion dynamics of the flaps undergoing liposuction debulking are studied by means of perioperative indocyanine green fluorescence angiography, as well as postoperative laser Doppler imaging.

RESULTS

 Patients undergoing lipectomy (n = 69; 57.5%) or liposuction (n = 51; 42.5%) debulking had a similar rate of postoperative complications. Partial necrosis was observed in 7.2% (lipectomy) versus 7.8% (liposuction) of flaps. Fluorescence angiography showed a substantial decrease in flap perfusion following the infiltration with an epinephrine-containing tumescent solution (74.3% ± 8.2% prior to infiltration versus 16.8% ± 7.1% after infiltration; p < 0.001), resulting in a dark flap appearance. Laser Doppler imaging confirmed the hypoperfusion on postoperative day 1.

CONCLUSION

 Secondary debulking of a lower extremity flap can be safely and efficiently performed through liposuction combined with peripheral excision of the defatted flap in a single stage. Perfusion studies may show a misleading hypoperfusion of the defatted flap, which does not accurately predict subsequent necrosis or complications.

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

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

Imaging in reconstructive microsurgery - current standards and latest trends

In microsurgery, many different imaging techniques are available in both flap and lymphatic surgery that all come with their own advantages and disadvantages. In flap surgery, CT angiography is considered as the gold standard. Among others, Doppler ultrasound, color Doppler ultrasound, ICG, and smartphone-based thermal cameras are valuable imaging techniques. In lymphatic surgery, photoacoustic imaging, laser tomography, contrast-enhanced magnetic resonance imaging, and high frequency ultrasound stand available to surgeons next to the current standard of lymphoscintigraphy. It is crucial to know the advantages and disadvantages to various techniques and highly adviced to microsurgeons be capable of using a variety of them.

Outcomes of DIEP flap reconstruction after pelvic cancer surgery: A retrospective multicenter case series

BACKGROUND

Flap reconstruction is often required after pelvic tumor resection to reduce wound complications. The use of perforator flaps has been shown to reduce donor site morbidity. The purpose of this study was to evaluate the outcomes of pedicled deep inferior epigastric perforator (pDIEP) flap reconstruction.

METHODS

This was a retrospective multicenter study of patients who underwent immediate pDIEP flap reconstruction for a pelvic or perineal defect after tumor resection between November 2012 and June 2022. The primary outcome was abdominal donor site morbidity, and the secondary outcome was perineal morbidity.

RESULTS

Thirty-four patients (median age, 57.5 years) who underwent pelvic exenteration (n = 31), extralevator abdominoperineal excision (n = 2), or extended vaginal hysterectomy (n = 1) were included. The most common indications were recurrent cervical (n = 19) and anal (n = 4) squamous cell carcinoma. Twenty-nine patients (85%) had a history of radiotherapy. Only one patient (3%) had major (Clavien-Dindo ≥ III) donor site complications (surgical site infection due to tumor recurrence). Eleven patients (32%) had at least one major recipient site complication (surgical site infection [n = 1], total [n = 2] or partial [n = 1] flap loss, perineal dehiscence [n = 2], hematoma [n = 1], fistula [n = 5]). No incisional or perineal hernias were observed during follow-up. Ninety-day survival was 100%.

CONCLUSION

Pedicled DIEP flap reconstructions performed by experienced surgical teams had good outcomes for perineal or vaginal reconstruction, with low abdominal morbidity, in patients with advanced pelvic malignancies who had undergone median laparotomy. The risks and benefits of this procedure should be carefully evaluated preoperatively using clinical and imaging data.

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.

Is Instillational Topical Negative Pressure Wound Therapy in Peri-Prosthetic Infections of the Breast Effective? A Pilot Study

Peri-prosthetic breast infections pose a risk of severe complications after breast implant surgery. The need to remove the breast implant, control the infection and perform additional surgical procedures are the consequences. Reimplantation of an alloplastic implant is only appropriate after an infection-free interval. In this retrospective cohort study, we investigated the effectiveness of negative pressure wound treatment with instillation and dwell time (NPWTi-d) on peri-prosthetic breast infections in combination with implant removal and antibiotic therapy. Twelve patients treated with NPWTi-d due to breast implant infection were included in the study. The bacterial burden was analyzed using wound swabs before and after NPWTi-d. Additionally, laboratory values were determined before NPWTi-d and immediately before wound closure. A total of 13 peri-prosthetic breast infections in 12 patients were treated using implant removal and NPWTi-d. In 76.9% (n = 10) of the cases, the patients had undergone alloplastic breast reconstruction following cancer-related mastectomy, whereas 23.1% (n = 3) of the patients had undergone breast augmentation for cosmetic reasons. The bacterial burden in the breast pocket decreased statistically significant after implant removal and NPWTi-d. No shift from Gram-positive to Gram-negative bacteria was observed. Inflammatory markers rapidly decreased following treatment. NPWTi-d had a positive impact on the healing process after peri-prosthetic breast infections, leading to a decrease in bacterial burden within the wounds and contributing to uneventful healing. Therefore, secondary reimplantation of breast prostheses might be positively influenced when compared to conventional implant removal and simple secondary closure. Further studies are required to conclusively establish the beneficial long-term effects of using NPWTi-d for the treatment of peri-prosthetic breast infections.

[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 Personalized Approach to Treat Advanced Stage Severely Contracted Joints in Dupuytren’s Disease with a Unique Skeletal Distraction Device—Utilizing Modern Imaging Tools to Enhance Safety for the Patient

Background: While surgical therapy for Dupuytren’s disease is a well-established standard procedure, severe joint flexion deformities in advanced Dupuytren’s disease remain challenging to treat. Skeletal distraction has proven to be an additional treatment option. Methods: We analyzed the surgical treatment algorithm, including the application of a skeletal distraction device, in patients with a flexion deformity due to Dupuytren’s disease, Iselin stage III or IV, who were operated on from 2003 to 2020 in our department. Results: From a total of 724 patients, we included the outcome of 55 patients’ fingers in this study, who had undergone additional skeletal joint distraction with our Erlangen device. Additional fasciotomy or fasciectomy, in a one- or two-staged procedure, was performed in all patients, according to the individual findings and necessities. The range of motion of the PIP joint improved from 12° to 53°. A number of complications, in all steps of the treatment, were noted in a total of 36.4% of patients, including the development of fractures (16.4%), followed by vessel injury, pin infections, and complex regional pain syndrome (5%). Conclusions: Additional skeletal distraction improves the range of motion of severely contracted joints in Dupuytren’s disease. Nevertheless, careful patient selection is necessary, due to the moderate rate of complications.