Internal mammary vessels, recipient vessels of choice for free tissue breast reconstruction?

A clinical application for arterial coupling and histomorphometric comparison of internal mammary and thoracodorsal arteries for safe use

BACKGROUND

In breast reconstruction, arterial coupling has been reported to be more favorable in the thoracodorsal artery (TDA) than the internal mammary artery (IMA). This technique may help overcome anastomosis in a small, deep space. Understanding the arteries' mechanical properties is crucial for breast reconstruction's safety and success.

METHODS

Abdominal-based free flap breast reconstructions performed by a single surgeon between 2020 and 2022 were retrospectively analyzed. The patients were classified by microanastomosis technique (handsewn and coupler device) to compare the rate of vascular revision. Histomorphometric analysis of arterial coupling in TDA and IMA was performed in 10 fresh cadavers for comparing wall thickness and composition, including densities of elastic fiber, smooth muscle, and collagen.

RESULTS

A total of 309 patients (339 reconstructed breasts) were included. There were 29 patients in the TDA handsewn group (A), 38 patients in the TDA coupler group (B), and 242 patients in the IMA handsewn group (C). The rates of arterial revision in groups A, B, and C were 0.00% (95%CI: 0.00%-11.03%), 2.5% (95%CI: 0.44%-12.88%), and 1.49% (95%CI: 0.58%-3.77%), respectively, with no statistically significant differences (p-value = .694). Histologically, the thickness of the tunica media and adventitia between IMA and TDA showed no significant difference. The density of elastic fiber was significantly higher in IMA (16.70%) than in TDA (0.79%) (p-value <.001).

CONCLUSION

The histologic characteristics of TDA are more favorable for arterial coupling than those of IMA. Arterial coupling is a safe option in situations where TDA anastomosis must be performed through a narrow and deep incision.

Risk of Pneumothorax With Internal Mammary Vessel Utilization in Autologous Breast Reconstruction

BACKGROUND

Complications associated with autologous breast reconstruction are well reported in the literature. Regardless of the type of free flap harvested, the anastomosis is most commonly performed to the recipient internal mammary vessels. Although pneumothorax is a known possible complication of breast surgery, incidence of pneumothorax in breast reconstruction involving the use of the internal mammary vessels is rarely discussed. The aim of our study was to determine the incidence of pneumothorax in deep inferior epigastric perforator (DIEP) flap breast reconstruction.

METHODS

A single-institution review was performed examining the incidence of pneumothorax in cases of DIEP flap breast reconstruction with anastomosis to the internal mammary vessels over a 4-year period. Intraoperative irrigation was used to visually assess for evidence of pneumothorax during recipient vessel dissection and anastomosis. Anteroposterior chest radiographs were obtained on the first postoperative day to assess for pneumothorax. Additional variables analyzed included type of retractor used during recipient vessel dissection and history of radiation.

RESULTS

A total of 180 patients underwent autologous DIEP breast reconstruction at our institution. The overall incidence of pneumothorax was 1.4 per 100 recipient vessel dissections and 2.2 per 100 patients undergoing breast reconstruction. There was a total of 4 cases of pneumothorax. Three were attributed to unknown causes, and 1 was due to direct injury to the parietal pleura via electrocautery.

CONCLUSION

The use of the internal mammary artery and vein as recipient vessels continues to be the most common and reliable recipient for autologous breast reconstruction. Based on our data, pneumothorax does not seem to be a common complication of this procedure. If concern for iatrogenic injury to the pleura arises intraoperatively, we suggest the use of a saline bubble test to investigate the possible injury. Routine postoperative radiographs are not indicated unless the patient develops symptoms suggestive of pneumothorax.

An unusual "venous circle" of the internal mammary vein encountered during microvascular anastomosis and implications for practice

The internal mammary vessels are commonly used for anastomosis in breast reconstruction. The anatomy when using the 2nd ICS has been shown to be predictable and hence preferentially used by the senior author. We present an unusual case of internal mammary vein bifurcation and immediate confluence forming a 'venous circle'.

Applications of rib sparing technique in internal mammary vessels exposure of abdominal free flap breast reconstructions: a 12-year single-center experience of 215 cases

Background

Internal mammary vessels (IMVs) are widely used recipient vessels in abdominal free flap breast reconstructions. Rib sparing technique is an alternative method with less damage in IMVs exposure. This study aims to investigate the factors influencing the selection of IMVs, as well as analyze the applicability and related factors of rib sparing technique in abdominal breast reconstruction.

Methods

Medical records of 215 patients who underwent abdominal free flap reconstruction from November 2006 to December 2017 in Fudan University Shanghai Cancer Center (FUSCC) were analyzed. Intercostal space (ICS) was measured from preoperative chest computed tomography scan. Factors influencing the choice of recipient vessels and rib sparing were analyzed. Surgery time, hospitalization and complications were assessed.

Results

Among all 218 flaps, 172 flaps used IMVs as the recipient vessels while 46 used other vessels. patients with immediate reconstruction (P=0.005) and axillary lymph nodes dissection (ALND) (P<0.001) were less likely to use IMVs. Patients' body mass index (BMI) and radiotherapy history showed no statistically significant differences between the two groups (P=0.338 and 0.811). In IMVs group, 62% cases used rib sparing technique. Compared with rib resection group, patients with rib sparing were taller (P=0.047) and with a wider ICS (2.65±0.54 vs. 2.25±0.38 cm, P<0.001). Rib sparing group had a shorter surgery and postoperative hospitalization time, as well as a lower complication rate, but the differences were not statistically significant (P=0.120, 0.450 and 0.612).

Conclusions

IMVs were used more frequently as the recipient vessels in abdominal free flap breast reconstructions, especially when axillary operation was not performed at the same time. Rib sparing technique had the potential to decrease surgery time, hospitalization days and complications rate. It could be applied in most of the patients with IMVs exposure, particularly in taller patients and patients with a wider ICS. Preoperative chest computed tomography scan can be used to assess the ICS width to provide operational suggestions.

Nipple-sparing mastectomy and breast reconstruction with a deep inferior epigastric perforator flap using thoracodorsal recipient vessels and a low lateral incision

BACKGROUND

Nipple-sparing mastectomy poses challenges in providing esthetically-pleasing immediate autologous breast reconstruction. This study was to investigate the outcomes of nipple-sparing mastectomy with breast reconstruction using free abdominal flaps between two different recipient sites.

METHODS

Between 2010 and 2016, 79 patients who underwent nipple-sparing mastectomy with autologous breast reconstruction using thoracodorsal (TD) vessels in 30 cases or internal mammary (IM) vessels in 49 cases were investigated. Demographics, intraoperative findings, complications, and quality of life using Breast-Q questionnaire were compared between two groups.

RESULTS

All flap survived. There was no statistical difference in age, BMI, ischemia time, and flap-used percentage. The TD artery had a statistically smaller diameter 1.8 ± 0.4 mm than the IM artery 2.7 ± 0.43 mm (p = 0.02). At a mean follow-up of 44.4 ± 35.2 months, there was no statistical difference in total complication rates between TD and IM groups (23.3% and 36.7%, respectively, p > 0.05). The "psychosocial well-being" of Breast-Q in TD group 83.9 ± 14.6 was statistically greater than IM group 72.8 ± 17.6 (p = 0.04).

CONCLUSIONS

Nipple-sparing mastectomy with immediate breast reconstruction using TD vessels with a low lateral scar is a safe procedure that provides an inconspicuous scar with better cosmesis and minimal complication rate.

MRA of the skin: mapping for advanced breast reconstructive surgery

Autologous breast reconstruction using muscle-sparing free flaps are becoming increasingly popular, although microvascular free flap reconstruction has been utilised for autologous breast reconstructions for >20 years. This innovative microsurgical technique involves meticulous dissection of artery-vein bundle (perforators) responsible for perfusion of the subcutaneous fat and skin of the flap; however, due to unpredictable anatomical variations, preoperative imaging of the donor site to select appropriate perforators has become routine. Preoperative imaging also reduces operating time and enhances the surgeon's confidence in choosing the appropriate donor site for harvesting flaps. Although computed tomography angiography has been widely used for preoperative imaging, concerns over excessive exposure to ionising radiation and poor iodinated contrast agent enhancement of the intramuscular perforator course has made magnetic resonance angiography, the first choice imaging modality in our centre. Magnetic resonance angiography with specific post-processing of the images has established itself as a reliable method for mapping tiny perforator vessels. Multiple donor sites can be imaged in a single setting without concern for ionising radiation exposure. This provides anatomical information of more reconstruction donor site options, so that a surgeon can design a flap of tissue centralised around the best perforator, as well as a back-up perforator, and even a back-up flap option located on a different region of the body. This information is especially helpful in patients with a history of scar tissue from previous surgeries, where the primary choice perforator is found to be damaged or unsuitable intraoperatively. In addition, chest magnetic resonance angiography evaluates recipient site blood vessel suitability including vessel diameters, course, and branching patterns. In this article we provide a broad overview of various skin flaps, clinical indications, advantages and disadvantages of each of these flaps, basic imaging technique, along with advanced sequences for visualising tiny arteries in the groin and in the chest. Post-processing techniques, structure of the report and how automation of the reporting system improves workflow is described. We also describe applications of magnetic resonance angiography in postoperative imaging.

Determining the best recipient vessel site for autologous microsurgical breast reconstruction with DIEP flaps: An anatomical study

INTRODUCTION

The deep inferior epigastric perforator (DIEP) flap is a reliable and reproducible technique for autologous microsurgical breast reconstruction. Several recipient vessels sites for microvascular anastomosis have been described such as the internal thoracic vessels, the thoracodorsal vessels, and the circumflex scapular vessels. Nonetheless, the choice of the recipient site depends mainly on individual operator's experience and preferences, and currently the best recipient vessel site is under debate. This anatomical observational study aimed to determine whether anatomy could address this dilemma by determining the best vessel diameter to match the donor with these three recipient sites.

METHODS

Our series reports 80 dissections of the three anatomical regions of interest. Forty formalin-preserved female cadavers were dissected bilaterally. Internal vessels diameter measurements were recorded with a vascular gauge ranging from 1.0 to 5.0 mm with successive half-millimeter graduations.

RESULTS

The median diameter of the deep inferior epigastric (DIEA), internal thoracic (ITA), circumflex scapular (CSA), and thoracodorsal arteries (TDA) were: 2.0, 2.5, 2.5, and 1.5 mm, respectively. The median diameter of the deep inferior epigastric, internal thoracic, circumflex scapular, and thoracodorsal veins were: 3.0, 3.0, 3.0, and 2.5 mm, respectively. At the individual level, the perfect match between DIEA and ITA was significantly more frequent than between DIEA and TDA (p = 0.002), and it was more frequent between DIEA and CSA than between DIEA and TDA (p = 0.009).

CONCLUSIONS

This study supports the use of the internal thoracic pedicle as the first recipient vessel choice, which should be considered, at least anatomically, as the best one with the closest diameter matching with the donor pedicle.

Total 'rib'-preservation technique of internal mammary vessel exposure for free flap breast reconstruction: A 5-year prospective cohort study and instructional video

Introduction

The total ‘rib’-preservation method of dissecting out the internal mammary vessels (IMV) during microvascular breast reconstruction aims to reduce free flap morbidity at the recipient site. We review our five-year experience with this technique.

Patients & methods

An analysis of a prospectively collected free flap data cohort was undertaken to determine the indications, operative details and reconstructive outcomes in all breast reconstruction patients undergoing IMV exposure using the total ‘rib’-preservation method by a single surgeon.

Results

178 consecutive breast free flaps (156 unilateral, 11 bilateral) were performed from 1st June 2008 to 31st May 2013 in 167 patients with a median age of 50 years (range 28–71). There were 154 DIEP flaps, 14 SIEA flaps, 7 muscle-sparing free TRAMs, 2 IGAP flaps and one free latissimus dorsi flap. 75% of the reconstructions (133/178) were immediate, 25% (45/178) were delayed. The mean inter-costal space distance was 20.9 mm (range 9–29). The mean time taken to expose and prepare the recipient IMV's was 54 min (range 17–131). The mean flap ischaemia time was 95 min (range 38–190). Free flap survival was 100%, although 2.2% (4 flaps) required a return to theatre for exploration and flap salvage. No patients complained of localised chest pain or tenderness at the recipient site and no chest wall contour deformity has been observed.

Discussion & conclusion

The total ‘rib’-preservation technique of IMV exposure is a safe, reliable and versatile method for microvascular breast reconstruction and should be considered as a valid alternative to the ‘rib’-sacrificing techniques.

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We review the rib-preservation technique for internal mammary vessel exposure by a single surgeon.

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An instructional video is presented depicting how to perform the rib-preserving technique step by step.

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The ‘rib’-preservation technique to dissect the internal mammary vessels is safe, reliable and reproducible.