"Double Barrel" Lymphaticovenous Anastomosis: A Useful Addition to a Supermicrosurgeon's Repertoire

Lymphovenous Coupler-Assisted Bypass for Immediate Lymphatic Reconstruction

BACKGROUND

 Breast cancer-related lymphedema is the most common cause of lymphedema in the United States and occurs in up to 50% of individuals receiving axillary lymph node dissection (ALND). Lymphovenous bypass (LVB) at the time of ALND may prevent lymphedema, but long-term results and anastomotic patency are unclear. This study evaluates the feasibility and outcomes of performing immediate lymphatic reconstruction via coupler-assisted bypass (CAB).

METHODS

 This is a retrospective review of all patients undergoing prophylactic LVB following ALND at two tertiary care centers between 2018 and 2022. Patients were divided into cohorts based on whether they received the "standard" end-to-end (E-E) suturing or CAB technique. The primary outcome of interest was development of lymphedema. Quantitative and qualitative assessments for lymphedema were performed preoperatively and at 3, 6, 12, and 24 months postoperatively.

RESULTS

 Overall, 63 LVBs were performed, of which 24 lymphatics underwent immediate reconstruction via "CAB" and 39 lymphatics via "standard" end-to-end suture. Patient characteristics, including body mass index, and treatment characteristics, including radiation therapy, did not significantly differ between groups. CAB was associated with a greater mean number of lymphatics bypassed per vein (standard 1.7 vs. CAB 2.6, p = 0.0001) and bypass to larger veins (standard 1.2 vs. CAB 2.2 mm, p < 0.0001). At a median follow-up of 14.7 months, 9.1% (1/11) of individuals receiving CAB developed lymphedema. These rates were similar to those seen following standard bypass at 4.8% (1/21), although within a significantly shorter follow-up duration (standard 7.8 vs. CAB 14.7 months, p = 0.0170).

CONCLUSION

 The CAB technique is a viable, effective technical alternative to the standard LVB technique. This comparative study of techniques in prophylactic LVB suggests that CABs maintain long-term patency, possibly due to the ease of anastomosing several lymphatics to single large caliber veins while reducing the technical demands of the procedure.

Validation of Novel Microsurgical Vessel Anastomosis Techniques: A Systematic Review

INTRODUCTION

 Thorough validation of novel microsurgical techniques is deemed essential before their integration into clinical practice. To achieve proper validation, the design of randomized controlled trials (RCTs) should be undertaken, accompanied by the execution of comprehensive statistical analyses, including confounder adjustment and power analysis. This systematic review aims to provide an encompassing overview of the validation methodologies employed in microsurgical studies, with a specific focus on innovative vessel anastomosis techniques.

METHODS

 A literature search was conducted in PubMed for articles describing the validation of novel microsurgical vessel anastomosis techniques in animal or human subjects.

RESULTS

 The literature search yielded 6,658 articles. A total of 6,564 articles were excluded based on title and abstract. Ninety-four articles were assessed for full-text eligibility. Forty-eight articles were included in this systematic review. Out of 30 comparative studies, 9 studies validated novel modified interrupted suture techniques, 6 studies modified continuous techniques, 6 studies modified sleeve anastomosis techniques, 1 study a modified vesselotomy technique, 7 studies sutureless techniques, and 1 study a modified lymphaticovenular anastomosis technique. Twenty-eight studies contained animals (n = 1,998). Fifteen animal studies were RCTs. Two studies contained human/cadaveric subjects (n = 29). Statistical power analysis and confounder adjustment were performed in one animal study. Out of 18 noncomparative studies, 5 studies validated novel modified interrupted suture techniques, 1 study a modified continuous technique, 2 studies modified sleeve anastomosis techniques, 4 studies modified vesselotomy techniques, 4 studies sutureless techniques, and 2 studies modified lymphaticovenular anastomosis techniques. Ten studies contained animal subjects (n = 320), with two RCTs. Eight studies contained human subjects (n = 173). Statistical power analysis and confounder adjustment were performed in none of the animal or human studies.

CONCLUSION

 The current methods of microsurgical technique validation should be reconsidered due to poor study design. Statistical analysis including confounder adjustment and power analysis should be performed as a standard method of novel technique validation.

Overlapping lockup lymphaticovenous anastomosis: A useful addition to supermicrosurgery

BACKGROUND

Lymphaticovenular anastomosis (LVA) is a minimally invasive surgical procedure used to treat lymphedema. This surgical procedure connects the superficial lymphatic vessels to nearby veins to establish lymphatic-venous pathways. One of the most common challenges encountered by lymphatic surgeons when performing LVA is a mismatch in the sizes of the veins and lymphatic vessels, with the effectiveness limited by technical constraints. We conducted a pilot study to evaluate the feasibility of an overlapping lockup anastomosis (OLA) LVA technique to address these problems.

METHODS

In this study, we present a novel OLA technique for LVA that addresses the challenges with conventional techniques. The OLA technique was used in 10 lymphedema patients between September 2022 and March 2023 to compare OLA and end-to-end anastomosis. The time required for anastomosis, method of anastomosis, patency rates, and lymphedema volume were evaluated in this study.

RESULTS

Of 123 LVAs, 44 were performed using the OLA technique in 10 patients, with indocyanine green lymphangiography revealing unobstructed drainage. A single case of slight fluid leakage occurred, which was resolved by reinforcing the sutures. The average anastomosis time for OLA and the end-to-end technique was 5.55 minutes and 12.1 minutes, respectively. The wounds of the patients healed without infection, and the subjective limb circumference decreased.

CONCLUSIONS

The OLA technique could serve as a valuable addition to the current LVA technique, especially for cases with a mismatch in the sizes of the lymphatic vessels and veins. This technique has the potential to promote the broader application of LVA in the treatment and prevention of lymphedema.

Imaging Modalities for Evaluating Lymphedema

Lymphedema is a progressive condition. Its therapy aims to reduce edema, prevent its progression, and provide psychosocial aid. Nonsurgical treatment in advanced stages is mostly insufficient. Therefore-in many cases-surgical procedures, such as to restore lymph flow or excise lymphedema tissues, are the only ways to improve patients' quality of life. Imaging modalities: Lymphoscintigraphy (LS), near-infrared fluorescent (NIRF) imaging-also termed indocyanine green (ICG) lymphography (ICG-L)-ultrasonography (US), magnetic resonance lymphangiography (MRL), computed tomography (CT), photoacoustic imaging (PAI), and optical coherence tomography (OCT) are standardized techniques, which can be utilized in lymphedema diagnosis, staging, treatment, and follow-up. Conclusions: The combined use of these imaging modalities and self-assessment questionnaires deliver objective parameters for choosing the most suitable surgical therapy and achieving the best possible postoperative outcome.