Predicting venous congestion before DIEP breast reconstruction by identifying atypical venous connections on preoperative CTA imaging

[Impact of the number of pregnancies on the venous outflow of DIEP flap in breast reconstruction: A clinical and CT-scan study]

INTRODUCTION

The DIEP (deep inferior epigastric perforator) flap is the "gold standard" for breast reconstruction after cancer, giving better benefits on the quality of life. The most common complication is the venous congestion, because of the dominance of superficial venous outflow while the flap is drained by the deep epigastric vein. Pregnancy, by its physiological and vascular modifications, can reduce the risk of the venous congestion. Few studies explored the impact of pregnancy on the DIEP vascularization.

MATERIAL AND METHODS

We studied the preoperative CT-scans of 104 patients who benefited reconstruction surgery by DIEP from January 2011 until March 2022. The patients were separated into 5 groups according to number of pregnancies. For each CT-scan, a concomitant vein of deep epigastric artery diameter/SIEV diameter ratio was performed on each side, to assess the relation between pregnancy and the reduction of venous complications.

RESULTS

The results showed an increase of this ratio with the number of pregnancies. Patients with no pregnancy (G0) have the highest complication rate, with 41.7% of venous congestion case. On the other hand, in the group of four pregnancies or more (G4), the complication rate was significantly lower, at 10%, and none venous congestion was observed. These results suggest the beneficial effects of pregnancy on vascularization and especially on venous drainage in the DIEP flap.

CONCLUSION

This study highlights the benefit effect of the number of pregnancies on the DIEP vascularization, especially for the reduction of the venous congestion risk. The ratio DIEV/SIEV may be a useful help to predict the risk of venous complications in nullparous patients. These results open to new studies to deepen the understanding of the physiological effects of the pregnancy on the breast reconstruction surgery.

The Effect of Venous Augmentation on Complication Rates in Deep Inferior Epigastric Perforator Breast Reconstruction

BACKGROUND

With the rising popularity of the deep inferior epigastric perforator (DIEP) flap in breast reconstruction, use of the superficial inferior epigastric vein (SIEV) to augment venous outflow has been proposed as a strategy to prevent venous congestion, a complication positively associated with flap volume. This study evaluated the impact of routine SIEV venous augmentation on the risk of vascular complications or operative fat necrosis in the context of flap size and operating time.

METHODS

A retrospective cohort study compared complication rates of patients with SIEV-augmented DIEP flaps to controls over a 3-year period. Outcomes assessed included vascular complications, defined as venous congestion or compromise requiring take-back, partial flap necrosis, total flap loss, as well as operative fat necrosis. Relative risk was modeled by Cox proportional hazard regression analysis. Sensitivity analysis was performed to assess for an interaction effect by flap mass.

RESULTS

The study sample included 197 patients with 316 flaps. The mean mass of the SIEV-augmented flaps was significantly greater than in the control group (832.9 vs. 653.9 g; p = 0.0007). After adjustment for flap characteristics, patient demographic factors, and comorbidities, pooled risk of vascular complication and operative fat necrosis was found to be significantly lower in the SIEV-augmented group compared to controls (hazard ratio = 0.33, 95% CI [0.11-1.00]; p = 0.0489). Sensitivity analysis demonstrated no effect interaction by flap weight (p = 0.5139).

CONCLUSION

Routine venous outflow augmentation via anastomosis of SIEV to the internal mammary vein perforator at the second intercostal space significantly reduced the risk of vascular complications and operative fat necrosis, regardless of flap weight. No significant increase in operative time was observed among cases in which augmentation was performed.

A systematic review of the scientific evidence of venous supercharging in autologous breast reconstruction with abdominally based flaps

BACKGROUND

Abdominally based free flaps are commonly used in breast reconstruction. A frequent complication is venous congestion, which might contribute to around 40% of flap failures. One way to deal with it is venous supercharging. The primary aim of this study was to investigate the scientific evidence for the effects of venous supercharging.

METHODS

A systematic literature search was conducted in PubMed, CINAHL, Embase, and Cochrane library. The included articles were critically appraised, and certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

RESULTS

Thirty-six studies were included. Most studies had serious study limitations and problems with directness. Three studies report 'routine' use of venous supercharging and performed it prophylactically in patients who did not have clinical signs of venous congestion. Seventeen studies report on flap complications, of which one is a randomised controlled trial demonstrating statistically significant lower complication rates in the intervention group. The overall certainty of evidence for the effect of a venous supercharging on flap complications, length of hospital stay and operative time, in patients without clinical signs of venous congestion, is very low (GRADE ⊕ ⊕ ⊝ ⊝), and low on and surgical takebacks (GRADE ⊕ ⊕ ⊝ ⊝). Twenty-one studies presented data on strategies and overall certainty of evidence for using radiological findings, preoperative measurements, and clinical risk factors to make decisions on venous supercharging is very low (GRADE ⊕ ⊝ ⊝ ⊝).

CONCLUSION

There is little scientific evidence for how to predict in which cases, without clinical signs of venous congestion, venous supercharging should be performed. The complication rate might be lower in patients in which a prophylactic venous anastomosis has been performed.

TRIAL REGISTRATION

PROSPERO (CRD42022353591).

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.

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.

Use of the superficial inferior epigastric vein in breast reconstruction with a deep inferior epigastric artery perforator flap

Background

Autologous breast reconstruction is highly regarded in reconstructive surgery after mastectomy. DIEP flap reconstruction represents the gold standard for autologous breast reconstruction. The major advantages of DIEP flap reconstruction are its adequate volume, large vascular caliber and pedicle length. Despite reliable anatomy, there are procedures where the plastic surgeon's creativity is required, not only to shape the new breast, but also to overcome microsurgical challenges. An important tool in these cases is the superficial epigastric vein (SIEV).

Methods

150 DIEP flap procedures performed between 2018 and 2021 were retrospectively evaluated for SIEV use. Intraoperative and postoperative data were analyzed. Rate of anastomosis revision, total and partial flap loss, fat necrosis and donor site complications were evaluated.

Results

In a total of 150 breast reconstructions with a DIEP flap performed in our clinic, the SIEV was used in 5 cases. The indication for using the SIEV was to improve the venous drainage of the flap or as a graft to reconstruct the main artery perforator. Among the 5 cases, no flap loss occurred.

Conclusions

Use of the SIEV is an excellent method to expand the microsurgical options in breast reconstruction with DIEP flap surgery. It provides a safe and reliable procedure to improve venous outflow in cases of inadequate outflow from the deep venous system. The SIEV could also provide a very good option for fast and reliable application as an interposition device in case of arterial complications.

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.

FlapMap Visual Language System for Vascular Imaging Prior to Microvascular Free Tissue Transfer

Preoperative vascular imaging has been shown to be beneficial before free tissue transfer procedures, especially for deep inferior epigastric perforator flap breast reconstruction. Although computerized tomography angiography and magnetic resonance angiogram are increasingly frequently performed, there is no standardized method for recording, analyzing, and communicating the vast amount of clinically relevant information that is obtained from these tomographic imaging studies. Herein, the authors propose a new visual language system for preoperative imaging called “FlapMap,” which allows for the creation of a clinically actionable, easily understood, and easily communicated single image that aids in preoperative planning before microvascular free tissue transfer.

Preoperative computed tomography assessment for a deep inferior epigastric perforator (DIEP) flap: a new easy technique from the Bologna experience

BACKGROUND

Deep inferior epigastric perforator (DIEP) flap reconstruction is the gold standard reconstructive technique for women undergoing breast cancer surgery. A preoperative computed tomography angiography (CTA)-dedicated protocol and 3D reconstructions are mandatory for correct surgical planning.

PURPOSE

To evaluate the diagnostic performance of a new preoperative CTA protocol and a new reconstruction method in the assessment of DIEP technique.

MATERIAL AND METHODS

A total of 263 women (median age 49 years, age range 26-73 years) underwent preoperative CTA examination before DIEP flap breast reconstruction. A CTA-dedicated protocol followed by 3D-reconstructions were performed. Identification, branching pattern, and caliber at origin were assessed for each perforator. Intraoperative findings were the standard of reference. The sensitivity, positive predictive value, and diagnostic accuracy of the preoperative CTA protocol were calculated.

RESULTS

In 255/263 (97%) patients, the dominant perforators assessed by CTA resulted adequate for surgical reconstruction. In 260/263 (99%) cases, the imaging localization of the dominant perforators corresponded with those seen intraoperatively (mean errors ≤1 cm). The preoperative CTA imaging sensitivity, positive predictive value, and diagnostic accuracy in determining the localization of perforators were 99% (95% CI 98-100), 100% and 99% (95% CI 98-100), respectively. No statistically significant differences were found between the CTA findings and the surgical findings for the assessment of branching pattern and caliber of the dominant perforators (P < 0.001).

CONCLUSION

The present protocol has demonstrated high accuracy in the CTA imaging assessment of the perforators before DIEP flap reconstruction with high reproducibility between CT and surgical findings.

In Vivo Perforasome Perfusion in Hemi-DIEP Flaps Evaluated with Indocyanine-green Fluorescence Angiography and Infrared Thermography

There are no in vivo studies that evaluate the effect of perforator dissection on the perfusion territory of a perforator (perforasome). In this study, indocyanine green fluorescence angiography (ICG-FA) and infrared thermography (IRT) were used intraoperatively to evaluate perforasome perfusion in hemi-DIEP flaps.

Seeing White: Management of TIVA during autologous breast reconstruction

Total IntraVenous Anaesthesia is frequently the anaesthetic of choice for enhanced recovery after surgery pathways during breast reconstruction free flap surgery. This relies upon the continuous intravenous infusion of propofol. We describe our experience of two patients where augmentation of a venously congested DIEP flap with a cephalic vein transposition procedure, risked interruption of the intravenous delivery of anaesthesia to the patient. We also share our steps taken to mitigate this risk going forward.

The accuracy of different modalities of perforator mapping for unilateral DIEP flap breast reconstruction: A systematic review and meta-analysis

BACKGROUND

Perforator mapping may be performed prior to deep inferior epigastric perforator (DIEP) flap breast reconstruction to guide perforator selection. However, the accuracy of different imaging modalities remains unknown. This review aimed to evaluate the accuracy of different modalities for locating perforators for unipedicled DIEP flap breast reconstruction.

METHODS

MEDLINE and EMBASE were searched from inception to 24th September 2019 for studies concerning adult women undergoing DIEP flap breast reconstruction with preoperative perforator mapping. The index test was pre-operative imaging and the reference standard was intraoperative identification.

RESULTS

21 articles with 1146 women were included. Six methods were described; handheld doppler, colour doppler (duplex) ultrasonography, computed tomography angiography, magnetic resonance angiography (MRA), direct infrared thermography with and without doppler. Meta-analysis revealed 94% (95% CI 88-99%) of DIEPs identified as the 'dominant perforator' on imaging were chosen as dominant perforators intraoperatively. Colour doppler (Duplex) ultrasonography had the lowest agreement (mean 74% [95% CI 67-81%]) whilst MRA had the highest agreement (mean 97% [95% CI 86-100%]). There was no statistically significant difference in the performance of different tests. All studies were subject to bias as the operators had knowledge of the index test prior to conducting the reference standard.

CONCLUSIONS

Based upon limited evidence, cross sectional (CT/MR) imaging modalities for preoperative DIEP mapping appear to have similar accuracy and perform better than ultrasound.

Meta-analysis of the effects of venous super-drainage in deep inferior epigastric artery perforator flaps for breast reconstruction

INTRODUCTION

Venous congestion is the most common vascular complication of the deep inferior epigastric artery perforator (DIEP) flaps. Adding a second venous drainage by anastomosing a flap vein and a recipient vein (super-drainage) is considered the solution of choice. Evidence to support this procedure, had not yet been confirmed by an analysis of the literature. We aimed to provide this evidence.

MATERIALS AND METHODS

We searched the literature (MedLine, Scopus, EMBASE, Cochrane Library, and Google Scholar), for studies discussing venous congestion and venous super-drainage in DIEP flap for breast reconstruction. Thirteen of the 35 articles compared results between one or two venous anastomoses. Meta-analysis was performed following PRISMA guidelines. Pooled risk ratio (RRs) for congestion, fat necrosis, partial necrosis, and total necrosis with corresponding 95% confidence intervals (CI) were calculated using a fixed-effect model with the Mantel-Haenszel method. The need to return to surgery (95% CI) was estimated with a random effect model using the DerSimonian and Liard method.

RESULTS

We showed a statistically significant advantage of super-drainage to reduce the venous congestion of the flap (RR: 0.12, 95% CI: 0.04-0.34, p-value <.001), partial flap necrosis (RR: 0.50, 95% CI: 0.30-0.84, p-value .008), total flap necrosis (RR: 0.31, 95% CI: 0.11-0.85, p-value .023), and the need to take the patient back to surgery for perfusion-related complications (RR: 0.45, 95% CI: 0.21-0.99, p value .048).

CONCLUSIONS

Performing a second venous anastomosis between the SIEV and a recipient vein (venous superdrainage) reduces venous congestion and related complications in DIEP flaps for breast reconstruction.

Fat Necrosis After DIEP Flap Breast Reconstruction: A Review of Perfusion-Related Causes

INTRODUCTION

Fat necrosis is a common complication for the deep inferior epigastric perforator (DIEP) flap. A thorough understanding of the factors associated with fat necrosis will aid operative planning for reconstructive surgeons.

METHODS

A systematic review of the literature was performed between January 1989 and April 2019. Studies were included if they reported on fat necrosis in DIEP flap or evaluated the perfusion of the DIEP flap. Twenty-eight out of 312 studies met the inclusion and exclusion criteria.

RESULTS

Fat necrosis rates ranged from 12.0 to 45.0% on clinical examination within the literature. The four main perforator-specific factors identified included perforator perfusion zones, perforator location, perforator number and venous congestion. Medial row perforators have a wider perfusion zone, while lateral row perforators have a narrow perfusion zone. Holm zone III has a higher rate of fat necrosis compared to Holm zone II. One to two perforators and more than five perforators and a Type III atypical connection between the superficial and deep venous system had a higher rate of fat necrosis.

CONCLUSION

The DIEP flap should incorporate between two and three perforators of a substantial calibre; Holm zone III should be excluded if able and careful review of the pre-operative imaging should be performed to analyse the connections between the deep and superficial venous system. There are multiple perfusion-related factors to consider when planning the DIEP flap and ultimately a patient-specific approach to the vascular anatomy is essential.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Different Hydraulic Constructs to Optimize the Venous Drainage of DIEP Flaps in Breast Reconstruction: Decisional Algorithm and Review of the Literature

BACKGROUND

 Venous congestion is the most common perfusion-related complication of deep inferior epigastric artery perforator (DIEP) flap. Several hydraulic constructs can be created for venous superdrainage in case of flap venous engorgement or as a preventive measure. These can be classified based on the choice of the draining vein of the flap, either a second deep inferior epigastric vein (DIEV) or a superficial inferior epigastric vein (SIEV), and of the recipient vein, either a vein of the chest or the DIEV.

METHODS

 We conducted a comprehensive systematic literature review in Medline, Scopus, EMBASE, Cochrane Library, and Google Scholar to find publications that reported on venous congestion in DIEP flap. The keywords used were DIEP Flap, breast reconstruction, venous congestion, supercharging, superdrainage, SIEV, and DIEV.

RESULTS

 Based on the studies found in the literature, we developed an algorithm to guide the surgeon's decision when choosing the veins for the superdrainage anastomosis.

CONCLUSION

 Several alternatives for venous anastomosis in superdrainage are available. We propose an algorithm to simplify the choice. The use of the ipsilateral SIEV to be connected to a vein of the chest appears to be advantageous. The anatomical position that allows the easiest anastomosis dictates which chest vein to favor.

How to Design and Harvest a Propeller Flap

Propeller flaps are local flaps based either on a subcutaneous pedicle, a single perforator, or vessels entering the flap in such a way so as to allow the flap to rotate on their axis. Depending on the kind of pedicle and the anatomical area, the preoperative investigation and the harvesting techniques may vary. An adequate knowledge of skin and subcutaneous tissue perfusion in the different areas of the body is very important to plan a propeller flap to be successful. The surgeon should begin by finding the most suitable perforators in the area surrounding the defect using available technology. The position, size, and shape of the flap are planned about this point. For perforator-pedicled propeller flaps, the procedure starts with an exploration from the margins of the defect or through a dedicated incision to visualize any perforators in the surroundings. The most suitable perforator is selected and isolated, the skin island is replanned, and the flap is harvested and rotated into the defect. The variations in surgical technique for other types of propellers and in specific anatomical areas are also described. Compared with free flaps, propeller flaps have the advantage of a simpler, shorter operation, without the need for a recipient vessel for microanastomosis. Yet, from a technical point of view, an adequate experience in dissecting perforators and the use of magnifying glasses are almost always required.

HoloLens-Based Vascular Localization System: Precision Evaluation Study With a Three-Dimensional Printed Model

Background

Vascular localization is crucial for perforator flap transfer. Augmented reality offers a novel method to seamlessly combine real information with virtual objects created by computed tomographic angiography to help the surgeon “see through” the skin and precisely localize the perforator. The head-mounted display augmented reality system HoloLens (Microsoft) could facilitate augmented reality–based perforator localization for a more convenient and safe procedure.

Objective

The aim of this study was to evaluate the precision of the HoloLens-based vascular localization system, as the most important performance indicator of a new localization system.

Methods

The precision of the HoloLens-based vascular localization system was tested in a simulated operating room under different conditions with a three-dimensional (3D) printed model. The coordinates of five pairs of points on the vascular map that could be easily identified on the 3D printed model and virtual model were detected by a probe, and the distance between the corresponding points was calculated as the navigation error.

Results

The mean errors were determined under different conditions, with a minimum error of 1.35 mm (SD 0.43) and maximum error of 3.18 mm (SD 1.32), which were within the clinically acceptable range. There were no significant differences in the errors obtained under different visual angles, different light intensities, or different states (static or motion). However, the error was larger when tested with light compared with that tested without light.

Conclusions

This precision evaluation demonstrated that the HoloLens system can precisely localize the perforator and potentially help the surgeon accomplish the operation. The authors recommend using HoloLens-based surgical navigation without light.

Interdisciplinary Treatment of Breast Cancer After Mastectomy With Autologous Breast Reconstruction Using Abdominal Free Flaps in a University Teaching Hospital-A Standardized and Safe Procedure

Background: Breast cancer is the most common malignancy in women. The interdisciplinary treatment is based on the histological tumor type, the TNM classification, and the patient's wishes. Following tumor resection and (neo-) adjuvant therapy strategies, breast reconstruction represents the final step in the individual interdisciplinary treatment plan. Although manifold flaps have been described, abdominal free flaps, such as the deep inferior epigastric artery perforator (DIEP) or the muscle-sparing transverse rectus abdominis myocutaneous (ms-TRAM) flap, are the current gold standard for autologous breast reconstruction. This retrospective study focuses on the safety of autologous breast reconstruction upon mastectomy using abdominal free flaps. Methods: From April 2012 until December 2018, 193 women received 217 abdominal free flaps for autologous breast reconstruction at the University Hospital of Erlangen. For perforator mapping, we performed computed tomography angiography (CTA). Venous anastomosis was standardized using a ring pin coupler system, and flap perfusion was assessed with fluorescence angiography. A retrospective analysis was performed based on medical records, the surgery report, and follow-up of outpatient course. Results: In most cases, autologous breast reconstruction was performed as a secondary reconstructive procedure after mastectomy and radiotherapy. In total, 132 ms1-TRAM, 23 ms2-TRAM, and 62 DIEP flaps were performed with 21 major complications (10%) during hospital stay including five free flap losses (2.3%). In all cases of free flap loss, we found an arterial thrombosis as the main cause. In 24 patients a bilateral breast reconstruction was performed without free flap loss. The majority of free flaps (96.7%) did not need additional supercharging or turbocharging to improve venous outflow. Median venous coupler size was 2.5 mm (range, 1.5-3.5 mm). Conclusion: Using CTA, intraoperative fluorescence angiography, titanized hernia meshes for rectus sheath reconstruction, and venous coupler systems, autologous breast reconstruction with DIEP or ms-TRAM free flaps is a safe and standardized procedure in high-volume microsurgery centers.

A review of visualized preoperative imaging with a focus on surgical procedures of the breast

Preoperative imaging has become a valuable tool in the planning of perforator flaps, and to date, computed tomographic angiography (CTA) has been shown to be the gold standard in this role. The evidence for this is a source of constant investigation, with advances in newer modalities coming to the fore. A literature review was undertaken to evaluate the current role of relevant imaging modalities in 'visualized surgery'-the ability to map anatomy prior to surgical incision. A focus is made on their accuracy in perforator mapping and correlation with improved clinical outcomes in the context of deep inferior epigastric artery perforator (DIEP) flap surgery. Other applications for preoperative imaging in breast surgery such as imaging of alternate donor sites or of the recipient site and imaging for volumetric assessment are also discussed. Preoperative imaging is integral to the planning of reconstructive breast surgery. This review has discussed the range of imaging techniques used to map and visualize perforator vasculature, and whilst there are varied clinical applications for the imaging modalities, CTA has been demonstrated to be the most precise and to confer the best clinical outcomes. Applications of the other imaging techniques are varied and these should remain as valid alternatives, particularly for patients where radiation or contrast exposure should be limited. Further studies could focus on the development of a more definitive protocol regarding the approach to preoperative imaging in breast surgery.

Preoperative cross-sectional mapping for deep inferior epigastric and profunda artery perforator flaps

Perforator flap-based breast reconstruction in a post mastectomy patient requires dissection of the artery-vein bundle (perforators) responsible for perfusion of the subcutaneous fat and skin of the flap. Traditionally, these reconstructions were performed with the transverse rectus abdominis myocutaneous (TRAM) flap, but autologous breast reconstruction using muscle sparing free flaps has become steadily more popular in recent years. Preoperative imaging to locate and evaluate candidate perforators has become an essential step before patients undergo the microsurgical procedure. Preoperative mapping assists with operative planning, reduces operating times, and brings anatomical variations to their attention. Pre-operative imaging also assists in choosing the appropriate donor site for harvesting flaps. Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) have been widely used for this type of preoperative imaging. Both MRA and CTA have their inherent advantages and disadvantages, and the preferred modality for this purpose varies by institution based on factors such as scanner availability, radiologist and surgeon experience, and comfort in interpreting the images. Concerns over excessive exposure to ionizing radiation and poor iodinated contrast agent enhancement of the intramuscular perforator course has made MRA the first-choice imaging modality in many centers. The purpose of the article is to review technique and protocols for the pre-operative CTA/MRA in patients who are being considered for a deep inferior epigastric artery perforator (DIEP) or profunda artery perforator (PAP) flap and to familiarize the reader with the normal and variant anatomic features of the deep inferior epigastric and PAP vessels along with the anatomic and surgical considerations used in the selection of perforator flap donor site for breast reconstruction post mastectomy.