Establishing the case for CT angiography in the preoperative imaging of abdominal wall perforators

Preoperative imaging of the donor site vasculature for deep inferior epigastric artery (DIEA) perforator flaps and other abdominal wall reconstructive flaps has become more commonplace. Abdominal wall computed tomography angiography (CTA) has been described as the most accurate and reproducible modality available for demonstrating the location, size, and course of individual perforators. We drew on our experience of 75 consecutive patients planned for DIEA-based flap surgery undertaking CTA at a single institution. Seven of these cases have been reported to highlight the utility of CTA for preoperative planning, emphasizing the unique information supplied by CTA that may influence operative outcome. Among all cases that underwent preoperative imaging with CTA, there was 100% flap survival, with no partial or complete flap necrosis. We found that in three of the cases described, the choice of operation was necessarily selected based on CTA findings (DIEA perforator flap, transverse rectus abdominis myocutaneous flap, and superficial superior epigastric artery flap). In addition, three cases demonstrate that CTA findings may dictate the decision to operate at all, and one case demonstrates the utility of CTA for evaluating the entire abdominal contents for comorbid conditions. Our experience with CTA for abdominal wall perforator mapping has been highly beneficial. CTA may guide operative technique and improve perforator selection in uncomplicated cases, and in difficult cases it can guide the most appropriate operation or indeed if an operation is appropriate at all. This is particularly the case in the setting of comorbidities or previous abdominal surgery.     

Advances in the pre‐operative planning of deep inferior epigastric artery perforator flaps: Magnetic resonance angiography

Imaging of the abdominal wall vasculature prior to deep inferior epigastric artery (DIEA) perforator (DIEP) flaps has been shown to significantly improve surgical outcomes. Although computed tomography angiography (CTA) has been shown to be highly accurate, it is associated with radiation exposure, and as such modalities without radiation exposure have been sought. Magnetic resonance angiography (MRA) has been proposed as such an option. We conducted a pilot study comparing MRA with CTA and with operative findings in six consecutive patients undergoing DIEP flaps for breast reconstruction. The DIEA, superficial inferior epigastric artery (SIEA) and perforators were all assessed with each modality. We found that the DIEA and SIEA were accurately imaged with both CTA and MRA, but that while MRA could identify some major perforators, CTA was more accurate than MRA for perforator mapping. As such, while MRA does have a role in the imaging of DIEA perforators, CTA is still the preferred modality. On the basis of these findings, a larger study into the role for MRA in this setting is warranted. © 2008 Wiley‐Liss, Inc. Microsurgery, 2009.     

A unique deep inferior epigastric artery perforator and implications for a muscle and fascia sparing vertical rectus abdominis myocutaneous flap: a case report

Despite the sacrifice of rectus abdominis muscle, the vertical rectus abdominis musculocutaneous (VRAM) flap is still a preferred option for perineal reconstruction. This journal has previously reported on the utility of preoperative computed tomographic angiography (CTA) in this setting to identify cases that are both suitable and unsuitable for rectus abdominis flaps after previous surgery. We report a case which highlights a unique example of the benefits of such imaging, with the largest deep inferior epigastric artery (DIEA) perforator described to date identified on imaging, and used to potentiate a donor-site sparing procedure. The use of this dominant perforator was able to limit donor site harvest to only a small cuff of anterior rectus sheath and a small segment of rectus abdominis, potentiating a muscle-sparing and fascia-sparing VRAM flap for perineal reconstruction. As such, preoperative CTA was found to be a useful tool in identifying a unique anatomical variant in the largest DIEA perforator described to date, and was used to potentiate a muscle-sparing and fascia-sparing VRAM flap for perineal reconstruction.     

Peritoneo‐cutaneous perforators in deep inferior epigastric perforator flaps: A cadaveric dissection and computed tomographic angiography study

Background: Cutaneous perforators that do not originate from the deep inferior epigastric artery (DIEA) are rare, but may significantly affect operative outcome. Peritoneal‐cutaneous perforators have been described as a source for augmenting the blood flow to a deep inferior epigastric perforator (DIEP) flap, however if unrecognized, may compromise flap survival. Methods: We reviewed 375 DIEA perforator (DIEP) flaps (325 with preoperative CTA and 50 cadaveric dissections) to investigate the incidence of this anomaly. Results: We detected this variation in 3/325 (1%) of DIEP flaps following preoperative computed tomography. In 1/50 (2%) of the cadaveric specimens, a peritoneal‐cutaneous perforator was found and injected with lead oxide contrast. It was shown to fill the cutaneous veins of the majority of the lower abdominal integument. Conclusion: Peritoneal‐cutaneous perforators are rare anatomical variations (4/375: 1.1%) that may have significant ramifications for surgery utilizing the vasculature of the abdominal wall. CTA was significantly able to detect this anomaly and aid operative planning. Preoperative CTA helps to safely identify individual vascular anatomy including rare variations. © 2008 Wiley‐Liss, Inc. Microsurgery, 2009.     

Improving the utility and reliability of the deep circumflex iliac artery perforator flap: the use of preoperative planning with CT angiography

Background: The deep circumflex iliac artery (DCIA) is rarely used as a perforator flap, despite a clear clinical need for thin osteocutaneous flaps, particularly in head and neck reconstruction. The poor adoption of such a flap is largely due to a poor understanding of the perforators of the DCIA, despite recent publications demonstrating suitable vascular anatomy of the DCIA perforators, particularly evident with the use of preoperative computed tomographic angiography (CTA). We have applied this method of peroperative imaging to successfully select those patients suitable for the DCIA perforator flap and use it clinically. Methods: We present a case series of patients who underwent DCIA perforator flap reconstruction following preoperative planning with CTA. Imaging findings, clinical course, and outcomes are presented. Results: Six out of seven patients planned for DCIA perforator flap reconstruction underwent a successful DCIA perforator flap, with imaging findings confirmed at operation, and without any flap loss, hernia, or other significant flap‐related morbidities. Because of abberent anatomy and change in defect following excision of pathology, one patient was converted to a free fibular flap. Conclusion: With preoperative CTA planning, the DCIA perforator flap is a versatile and feasible flap for reconstruction of the mandible and extremities. © 2011 Wiley Periodicals, Inc. Microsurgery, 2011.     

Computed tomographic angiography: assessing outcomes

Perforator flaps are preferable for breast reconstruction after mastectomy in many patients. Preoperative imaging of the perforators and source vessels is desirable to reduce surgeon stress, limit donor and recipient site complications, and minimize operative time and associated costs. Computed tomographic angiography (CTA) has been shown to provide highly accurate representations of vascular anatomy with excellent spatial resolution. A critical review of the currently available literature was performed to identify the benefits of preoperative imaging (specifically CTA) in perforator flap reconstruction.     

The profunda femoris artery "fourth perforator" island flap: a new perforator flap in lower-limb reconstruction

Although the lateral thigh flap has been well described as a fasciocutaneous flap based on one or more of the four perforators of the profunda femoris artery, the role for these individual perforators as perforator flaps has not been described. These profunda femoris artery perforators offer a particularly useful option in lower-limb reconstruction. In fact, a perforator flap based on the profunda femoris artery fourth perforator (PFA-P4) has not been described to our knowledge. We describe the utility of the PFA-P4 flap, offering modes of preoperative imaging and a role for its use in lower-limb reconstruction. Computed tomographic angiography (CTA) was able to identify the location and course of a PFA-P4, and Doppler ultrasound confirmed the CTA findings. A FA-P4 flap was designed and harvested, with direct closure of the donor site achieved. There were no operative complications. Perforator flaps based on the perforating branches of the profunda femoris artery have not been widely described, largely due to individual variability in perforator anatomy. With the advent of CTA for perforator mapping, the "freestyle" nature of such flaps is eliminated, and perforator flaps such as the PFA-P4 flap can be planned and harvested safely and confidently.     

Anatomical variations in the harvest of anterolateral thigh flap perforators: a cadaveric and clinical study

Background: The anterolateral thigh (ALT) flap has become increasingly popular due to its versatility and minimal donor site morbidity. Its major limitation has been uncertainty in predicting perforator anatomy, with the occasional absence of suitable perforators and high variability in their size and course. The variability of this anatomy has not been adequately explored previously. Methods: A cadaveric study was undertaken, in which 19 thighs (from 10 fresh cadavers) underwent contrast injection and angiographic imaging. Anatomical variations of the vasculature were recorded. A clinical study of 44 patients undergoing ALT flap reconstruction was also undertaken. Perforator anatomy was described in the first 32 patients, and the subsequent 12 patients underwent computed tomography angiography with a view to predicting individual anatomy and improving operative outcome. Results: Cadaver angiography was able to highlight and classify the variations in arterial anatomy, with four patterns observed and marked variability between cases. In 32 patients undergoing ALT flaps without preoperative CT angiography (CTA), five patients (16%) did not have any suitable perforators from the descending branch of the lateral circumflex femoral artery. By selecting the limb of choice with preoperative CTA, the incidence of flap unsuitability was reduced to 0%. Comparing CTA with Doppler, CTA was more accurate (sensitivity 100%) and provided more information. Conclusion: The perforators supplying the ALT flap show significant variability in location and course, with the potential for unsuitable perforators limiting flap success. Preoperative CTA can demonstrate the vascular anatomy and can aid perforator selection and operative success. © 2008 Wiley‐Liss, Inc. Microsurgery, 2009. [This is a corrected version of the abstract first published online on 22 October 2008 — the corrected version appears in print.]     

Computed tomography angiography imaging for the chimeric anterolateral thigh flap in reconstruction of full thickness buccal defect

Background: Microvascular free flap transplantation is the current most common choice for reconstruction of difficult through‐and‐through buccal defect after cancer extirpation. The chimeric anterolateral thigh (ALT) flap is an ideal flap to cover this full thickness defect, but variation in the location of perforators is a major concern. Herein, we introduce computed tomographic angiography (CTA)‐guided mathematical perforators mapping for chimeric ALT flap design and harvest. Methods: Between September 2008 and March 2009, nine patients with head and neck tumour underwent preoperative CTA perforator mapping before free ALT flap reconstruction of full thickness buccal defects. The perforators were marked on a 64‐section multi‐detector CT image for each patient, and the actual perforator locations were correlated with the intra‐operative dissection. The donor limb of choice, either right or left, was also selected based on the dominant vascularity. Flap success rates, any associated morbidity and complications were recorded. Results: A total of 23 perforators were identified on CTA image preoperatively. Twenty‐two of these perforators were chosen for chimeric flap design, and all were located as the CTA predicted, with the rate of utilization being 95.7% (22/23). There were two post‐operative complications, including one partial flap necrosis and one microstomia. All of the ALT flaps survived, and there was no donor site morbidity. Conclusions: Preoperative CTA allows accurate perforator mapping and evaluation of the dominant vascularity. It helps the surgeon to get an ideal designing of the chimeric ALT flap with two skin paddles based on individual perforators, but only one vascular anastomosis in reconstruction of full thickness buccal defects.     

A subfascial variant of the deep inferior epigastric artery demonstrated by preoperative multidetector computed tomographic angiography: A case report

Precise preoperative imaging by multidetector computed tomographic (MDCT) angiography for planning of deep inferior epigastric artery perforator (DIEP) flap dissection has been reported for enormous advantages in terms of reduced operative time and minimized flap‐related complications. This case report shows a particularly rare anatomical subfascia variant of deep inferior epigastric artery (DIEA) which can be preoperatively demonstrated by MDCT angiogram. Therefore, the intraoperative finding also confirms the radiologic data and results in meticulous flap harvesting during incision on anterior rectus sheath. Additionally, the authors emphasize on performing preoperative high quality imaging for DIEP intervention precisely for specific vulnerable course of subfascial plane DIEP, which is rare but tends to be at risk without foreknowing its exact course. © 2009 Wiley‐Liss, Inc. Microsurgery, 2010.     

Computed tomographic angiography: clinical applications

There has been a move towards increasingly refined techniques for autologous breast reconstruction, and given the substantial inter-individual variability of perforator anatomy, the need for reliable, accurate methods of vascular imaging has been sought. Computed tomographic angiography (CTA) can offer a range of applications in autologous breast reconstruction to aid surgical planning and improved outcomes. This article explores the utility of CTA in imaging perforators, pedicles and recipient vessels across a wide range of flap types and donor sites. CTA has a range of clinical applications in autologous breast reconstruction, and can aid operative planning and improve outcomes.     

Computed tomography-based preoperative vascular imaging in autologous breast reconstruction: A Canadian perspective

There appears to be increased use of computed tomography angiography (CTA) in the preoperative planning of autologous perforator flap breast reconstruction. Despite the advantages of providing superior anatomical detail, concerns regarding cost and radiation exposure of this technique remain. In the current study, a paper-based survey was distributed to 44 plastic surgeons with a special interest in breast reconstruction at 19 different centres across Canada to collect their perspectives and practice characteristics with respect to the use of CTA as a preoperative imaging modality in breast reconstruction. The response rate of the survey was 75%. The majority of respondents commonly use perforator flap breast reconstruction and CTA in their breast reconstruction practice. Surgeons identified particular benefits of CTA in patients who had previously undergone abdominal surgery. However, more than one-half of the overall cohort was concerned about radiation exposure associated with CTA. A review of the literature suggests that it may be worthwhile to reduce the unnecessary risks of additional radiation exposure to the breast cancer population. A prospective study may help to better define the group of patients in whom CTA will provide optimal benefits in terms of reducing perioperative microvascular morbidity.     

Correlating the deep inferior epigastric artery branching pattern with type of abdominal free flap performed in a series of 145 breast reconstruction patients

INTRODUCTION

The deep inferior epigastric perforator (DIEP) flap is currently viewed as the gold standard in autologous breast reconstruction. We studied three-dimensional computed tomography angiography (CTA) in 145 patients undergoing free abdominal flap breast reconstruction to try to correlate deep inferior epigastric artery (DIEA) branching pattern with the type of flap performed and patient outcome. Today, reconstructive breast surgeons have become more experienced in raising DIEP flaps and operative times are becoming more acceptable. However, there remains significant interest in finding ways to aid this challenging dissection.

METHODS

We retrospectively evaluated consecutive patients between January 2007 and August 2008. CTAs were analysed using the Moon and Taylor (1988) classification of the DIEA branching pattern. Data gathered included pre-operative morbidity, type of abdominal wall free flap performed, length of operation, length of stay and complications.

RESULTS

Some 150 breast reconstructions were performed in 145 patients. There were 67 DIEP flaps, 69 MS-2 transverse rectus abdominis myocutaneous (TRAM) flaps and 14 MS-1 TRAM flaps (where MS-1 spares the lateral muscle and MS-2 spares both lateral and medial segments). Proportionally more DIEP flaps were performed in patients with a type 2 branching pattern. There was one flap loss (0.67%).

CONCLUSIONS

In this large CTA series, we found a type 1 (single artery) DIEA pattern most frequently, in contrast to the predominance of the type 2 bifurcating pattern observed previously. The higher proportion of DIEP flaps performed in the type 2 pattern patients is consistent with the documented shorter intramuscular course in this group. We have found CTA useful for faster selection of the best hemiabdomen for dissection and flap loss rates in our unit have reduced from 1.5% to 0.67%.     

Improving Outcomes in Autologous Breast Reconstruction

Autologous breast reconstruction can often provide a more aesthetic outcome than other options for breast reconstruction because breast volume and shape can be extensively modified based on individual need, the texture of the reconstructed breast is a closer match to the native breast, and complications such as capsular contracture are avoided. However, with these benefits come the potential for complications unique to autologous tissue transfer. While overall complications are low, there are ways to maximize operative success and minimize the risk of complications. Deep inferior epigastric artery perforator (DIEP) flaps, the current mainstay in choice of autologous reconstruction, provide generally good outcomes. However, improvements in outcomes can still be achieved with a better understanding of individual anatomy. Perforator size, location, intramuscular and subcutaneous course, and association with motor nerves are all factors that can significantly affect operative technique, length of operation, and operative outcomes. With significant variation between individuals, preoperative imaging has become an essential element of DIEP flap surgery. Computed tomography angiography (CTA) is currently the gold standard but evolving techniques such as magnetic resonance angiography (MRA) and image-guided stereotaxy are rapidly contributing to improved outcomes. W. M. Rozen and M. W. Ashton contributed equally to this work.     

Preoperative planning of deep inferior epigastric artery perforator flap reconstruction with multislice-CT angiography: imaging findings and initial experience.

BACKGROUND: Autologous breast reconstruction with abdominal tissue is one of the best options after mastectomy. Reconstruction with deep inferior epigastric perforator (DIEAP) flaps requires a precise location and preoperative evaluation of perforating vessels. The objective of this report is to demonstrate the usefulness of multislice-CT (MSCT) angiography for preoperative planning in patients undergoing DIEAP flap reconstruction. METHODS: Six consecutive women were considered for breast reconstruction with DIEAP flaps after previous mastectomy for breast cancer. Preoperative MSCT angiography was performed to localise the arterial perforators. Axial images, multiplanar reconstructions (MPR) and 3D volume-rendered images were analysed. Findings were correlated with surgery. Initial experience and imaging findings will be described. RESULTS: Accurate identification of the main perforators was achieved in all six patients with a very satisfactory concordance between MSCT angiography and surgical findings. No unreported vessels were found. Location, course, anatomical variations and relations of the superficial inferior epigastric artery were reported. The very small perforators, were equally evaluated and described. CONCLUSIONS: Preoperative evaluation of perforator arteries with MSCT angiography is feasible in patients undergoing breast reconstruction. This technique provides a noninvasive global approach of the vascular anatomy and the entire anterior abdominal wall. However, more patients need to be evaluated in order to clarify the potential aspects pointed in this report.     

Contrast-enhanced magnetic resonance angiography for preoperative imaging of deep inferior epigastric artery perforator flaps: advantages and disadvantages compared with computed tomography angiography: a United Kingdom perspective

The anatomy of the anterior abdominal wall is highly variable and leads to uncertainty when harvesting a deep inferior epigastric artery perforator flap. Presurgical imaging has been shown to reduce the operating time, as well as reduce the rates of flap and donor site complications. The importance of imaging of the venous system has also been recognized for reducing the risk of venous congestion. The modalities currently available for presurgical imaging include handheld Doppler ultrasound, duplex ultrasound, computed tomographic angiography (CTA), and contrast-enhanced magnetic resonance angiography (CE-MRA). Of these, the most promising are CTA and CE-MRA, and advantages and disadvantages exist for both modalities. In this article, we review the use of CE-MRA for preoperative flap imaging and report our experience with its use in deep inferior epigastric artery perforator flap harvest, as well as compare it with CTA. We also explore the future directions for presurgical flap imaging.     

3D CT angiography of abdominal wall vascular perforators to plan DIEAP flaps

PURPOSE: Since the first report of TRAM flap reconstruction, there have been numerous studies to reduce complications of elective breast reconstruction. Current methods of preoperative perforator localization can be time-consuming, inaccurate, and imprecise. Thus, we sought to evaluate ultra-high resolution 3D CT angiography for the preoperative mapping of DIEAP flap perforating vessels. METHODS: We reviewed all perforator-based breast reconstructions performed over a 5-month period. Candidates for DIEAP flap reconstruction were sent for a focused CT scan of the abdominal wall, using the 64 slice multi-detector CT scanner. RESULTS: This article presents our first 23 flaps in 17 patients with preoperative ultra-high resolution 3D CT angiography. The reconstruction plan changed in three patients (18%). There was one take-back for venous congestion, but no partial or total flap loss. CONCLUSIONS: Preoperative perforator flap planning for breast reconstruction utilizing 3D CT angiogram is safe, easy to read, and can change the operative plan.     

Modifying techniques in deep inferior epigastric artery perforator flap harvest with the use of preoperative imaging

New techniques in the harvest of deep inferior epigastric artery perforator (DIEP) flaps have become introduced as a result of modern imaging technologies that can allow virtual surgery to be achieved preoperatively. With computed tomographic angiography, individual anatomy can be appreciated in detail to a level not previously appreciated. These imaging techniques can be successfully used to guide DIEP flap surgery. ‘Optimal’ perforators can be selected based on size, location, intramuscular and subcutaneous course, and their association with motor nerves. Flap design can be safely achieved based on the cutaneous distribution of perforators. Abdominal wall closure can be improved based on the abdominal contour seen with imaging. Preoperative planning can aid patient selection, plan all aspects of the operative technique, reduce operating time and improve operative outcomes.