Is Holm Zone III safe from fat necrosis in medial row perforator-based deep inferior epigastric perforator flaps?

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.

Free-style technique versus computed tomographic angiography-guided perforator selection in deep inferior epigastric perforator flap harvest: A prospective clinical study

BACKGROUND

Computed tomographic angiography (CTA) is the preferred diagnostic tool in preoperative deep inferior epigastric perforator (DIEP) flap assessment, though some surgeons prefer approaching perforator selection with intraoperative findings alone.

METHODS

This prospective observational study conducted between 2015 and 2020 assessed our intraoperative decision-making "free-style" technique for DIEP flap harvest. Any patient with indication for immediate or delayed breast reconstruction using abdominally based flaps and who received preoperative CTA was enrolled. Only unilateral cases performed by the same surgeon were considered. Allergy to iodine-based contrast media, renal impairment and claustrophobia were other exclusion criteria. Primary endpoint consisted in comparing operative times and complication rates between free-style technique and CTA-guided approach. Secondary endpoints included evaluation of agreement rate between intraoperative findings and CTA, and identification of variables affecting operative time and complication rate. Demographics, surgical information, agreement versus non-agreement and complications were collected.

RESULTS

Starting from 206 patients, 100 were enrolled. Fifty were assigned to Group A, receiving DIEP flap with free-style technique. The other 50 were assigned to Group B, receiving DIEP flap with CTA-guided perforators selection. Study groups' demographics were homogenous. Operative time was statistically lower (p = .036) in free-style group (252.4 ± 44.77 min vs. 265.6 ± 31.67 min). Complication rates were higher in CTA-guided group (10% vs. 2%) though this was not significant (p = .092). Overall agreement rate in dominant perforator selection between intraoperatively and CTA-based assessment was 81%. Multiple regression analysis showed no variable increased complication rate, though CTA-guided approach, BMI > 30 and harvesting more than one perforator were respectively associated with B-coefficient of 17.391 (2.430-32.351, 95% CI) [p = .023], 3.50 (0.640-6.379, 95% CI) [p = .017] and 18.887 (6.232-31.542, 95% CI) [p = .004], predicting increased operative time.

CONCLUSIONS

The free-style technique proved to be a useful tool for guiding DIEP flap harvest with good sensibility in detecting the dominant perforator suggested by CTA without statistically increasing surgery duration and complications.

Perforator Characteristics and Impact on Postoperative Outcomes in DIEP Flap Breast Reconstruction: A Systematic Review and Meta-Analysis

BACKGROUND

 High-quality evidence on perforator selection in deep inferior epigastric perforator (DIEP) flap harvesting is lacking, making preoperative planning and choice of perforators "surgeon-specific." This lack of consensus is a subject of continuous debate among microsurgeons. We aimed to systematically review perforator characteristics and their impact on DIEP flap breast reconstruction outcomes.

METHODS

 We conducted a systematic review and meta-analysis across six databases: ClinicalTrials.gov, Cochrane Library, Medline, Ovid Embase, PubMed, and Web of Science for all studies on DIEP flap breast reconstruction focused on perforator characteristics-caliber, number, and location. The primary goal was to analyze the impact of perforator characteristics on partial and/or total flap failure and fat necrosis. Data was analyzed using RevMan V5.3.

RESULTS

 Initial search gave us 2,768 articles of which 17 were included in our review. Pooled analysis did not show any statistically significant correlations between partial and/or total flap failure and perforator number, or perforator location. Sensitivity analysis accounting for heterogeneity across studies showed that, the risk for fat necrosis was significantly higher if single perforators (relative risk [RR] = 2.0, 95% confidence interval [CI] = 1.5-2.6, I ² = 39%) and medial row perforators (RR = 2.7, 95% CI = 1.8-3.9, I ² = 0%) were used.

CONCLUSION

 Our findings suggest that a single dominant perforator and medial row perforators may be associated with higher risk of fat necrosis after DIEP flap breast reconstruction. Adopting a standardized perforator selection algorithm may facilitate operative decision making, shorten the learning curve for novice surgeons, and optimize postoperative outcomes by minimizing the burden of major complications. This in turn would help improve patient satisfaction and quality of life.

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 .

Intraoperative Tissue Perfusion Measurement by Laser Speckle Imaging: A Potential Aid for Reducing Postoperative Complications in Free Flap Breast Reconstruction

Adequate tissue perfusion is essential to minimize postoperative complications following microsurgery. Intraoperative knowledge of tissue perfusion could aid surgical decision-making and result in reduced complications. Laser speckle imaging is a new, noninvasive technique for mapping tissue perfusion. This article discusses the feasibility of using laser speckle imaging during free flap breast reconstruction and its potential to identify areas of inadequate perfusion, thus reducing surgical complications. Adult patients scheduled to undergo free flap breast reconstruction were recruited into the study. Laser speckle images were obtained from the abdominal and breast areas at different stages intraoperatively. Zonal perfusion was compared with the Holm classification and clinical observations. Twenty patients scheduled to undergo free flap breast reconstruction were recruited (23 reconstructed breasts) (mean age, 50 years; range, 32 to 68 years). Flap zonal perfusion was 238 (187 to 313), 222 (120 to 265), 206 (120 to 265), and 125 (102 to 220) perfusion units for zones I, II, III, and IV, respectively (analysis of variance, p < 0.0001). Zonal area with perfusion below an arbitrary perfusion threshold were 20 (0.3 to 75), 41 (3 to 99), 49 (9 to 97), and 99 (25 to 100) percent, respectively (analysis of variance, p < 0.0001). One example is presented to illustrate potential intraoperative uses for laser speckle imaging. This study shows that laser speckle imaging is a feasible, noninvasive technique for intraoperative mapping of tissue perfusion during free flap breast reconstruction. Zonal tissue perfusion was reduced across the Holm classification. Observations indicated the potential for laser speckle imaging to provide additional information to augment surgical decision-making by detection of inadequate tissue perfusion. This highlights the opportunity for surgeons to consider additional aids for intraoperative tissue perfusion assessment to help reduce perfusion-related complications. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Diagnostic, IV.

The Influence of a Pfannenstiel Scar on Venous Anatomy of the Lower Abdominal Wall and Implications for Deep Inferior Epigastric Artery Perforator Flap Breast Reconstruction

BACKGROUND

A Pfannenstiel incision involves the obstruction of superficial venous pathways and functional diversion of flow through alternative pathways and adjacent vessels. This study investigated the effect of a prior Pfannenstiel incision on venous anatomy of the lower abdominal wall; specifically, the superficial inferior epigastric vein (SIEV), using computed tomographic angiography.

METHODS

A case-control study was performed of 50 patients with Pfannenstiel scars and 50 age-matched, body mass index-matched control patients without Pfannenstiel scars. The authors compared the number of direct/indirect and total communications between the SIEV and deep inferior epigastric artery perforator (DIEP) venae comitantes, midline crossover, and other SIEV-related anatomical changes by using computed tomographic angiography. Flap-related clinical outcomes and donor-site-related complications were also assessed.

RESULT

The median number of direct and total communications between the SIEV and DIEP venae comitantes in the study group was greater than in the control group. The percentage of SIEVs having more than two branching patterns per hemiabdomen was significantly higher in the study group than in the control group. The study group also showed a significantly lower rate of fat necrosis compared with the control group (p = 0.03). The rate of donor-site seroma was significantly higher in the study group.

CONCLUSION

This study suggests that the presence of a Pfannenstiel scar may promote the development of direct and total communications between the SIEV and DIEP venae comitantes and branching within the SIEV in the lower abdominal wall, which may facilitate venous drainage of adipose tissue in DIEP flap breast reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Volumetric Planning Using Computed Tomographic Angiography Improves Clinical Outcomes in DIEP Flap Breast Reconstruction

BACKGROUND

The present study evaluated outcomes of deep inferior epigastric perforator (DIEP) flap breast reconstruction using volumetric planning-which is preoperative planning based on volumetric data of the breast and flap estimated from computed tomographic angiography.

METHODS

A prospective review of three patient cohorts undergoing DIEP flap breast reconstruction from June of 2009 to February of 2015 was performed. Cohort 1 comprised 48 cases in which no volumetric planning was used. Cohort 2 included the next 101 consecutive cases undergoing breast reconstruction according to an algorithm based on volumetric planning. Cohort 3 consisted of the next 109 consecutive cases using a modified algorithm. The inset rate (weight ratio of the inset flap to harvested flap) was estimated during volumetric planning, and specific surgical strategies, such as incorporating multiple perforators, conducting venous augmentation (cohort 2), or harvesting bipedicled flaps (cohort 3), were used with reference to it. Rates of perfusion-related complications were compared.

RESULTS

All but one flap survived completely. Fat necrosis occurred in 9.7 percent. Overall, the perfusion-related complication rate was 22.9 percent of cohort 1, 10.9 percent in cohort 2, and 5.6 percent in cohort 3 (p = 0.006). The fat necrosis rates were 19.1, 9.9, and 5.6 percent in cohorts 1, 2, and 3, respectively (p = 0.032). A multivariate analysis demonstrated that volumetric planning had independent benefits for preventing perfusion-related complications (p = 0.003).

CONCLUSION

The authors' results suggest that volumetric planning can facilitate elaborate planning and reduce perfusion-related complications, enabling reliable breast reconstruction using DIEP flaps.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Stacked and bipedicled abdominal free flaps for breast reconstruction: considerations for shaping

BACKGROUND

Stacked and bipedicled abdominal flaps are useful in women who require a large breast reconstruction but have relative paucity of abdominal tissue. A new classification system is described to assist the surgeon in achieving the best possible aesthetic outcome.

METHODS

A retrospective review of 25 consecutive stacked and/or bipedicled deep inferior epigastric perforator (DIEP) flap reconstructions was assessed from 2009 to 2014. Demographic data and key variables were prospectively collected in our breast reconstruction database and an aesthetic classification devised. There are four main subtypes, (I) folded; (II) divided; (III) coned; and (IV) divided and folded. Each of these subtypes can be moulded in a symmetrically or asymmetrically fashion depending on the contralateral breast shape together with distribution and consistency of fat within the abdominal flap.

RESULTS

Of the 25 patients, three-quarter were immediate reconstruction, with an average age of 48 years and a median follow-up of 2 years 10 months. Just over half the patients (57%) had bipedicle flaps with two recipient donor vessels with the remaining 43% had stacked flaps. The most common recipient sites are the thoracodorsal vessels (62%) and intercostal perforators (26%). The average abdominal pannus weight was 610 grams (SD: 320 grams), with a hemi-abdominal weight of 305 grams. Two patients had haematomas, of which one lost their reconstruction. Another patient had a venous congestion flap which was salvaged.

CONCLUSIONS

Bipedicled or stacked abdominal flaps allow the all four zones of the abdominal tissue to be used in unilateral breast reconstruction. The approach of tailoring the abdominal flaps to match the contralateral breast reconstruction is largely an art form. The paper aims to bring some meaningful system to aid the surgeon to achieve the best possible outcome with the components presented to them.

[Benefit of simultaneous contralateral breast symmetry procedure with unilateral breast reconstruction using DIEP flaps. About 33 cases]

BACKGROUND

After unilateral breast reconstruction, a procedure on the contralateral breast is often needed to achieve symmetry. Here, we present a single surgeon's experience with performing contralateral symmetry procedures simultaneously with DIEP flap.

METHODS

We evaluated 33 consecutive patients (mean age, 52.1 years) who underwent DIEP flap unilateral breast reconstruction and a simultaneous contralateral breast procedure performed and 2 patients with delayed controlateral symmetry procedures. A single-stage breast cancer reconstruction is successful if after the original reconstruction no correction for revision of breast mound, or contralateral breast procedures are performed, under general anesthetic, to complete the reconstruction.

RESULTS

In 24 patients (73%), breast reconstruction was completed after a single stage with one general anesthetic, and in 8 patients (24%), revisions were performed with two general anesthetic (7 patients) and three general anesthetic in one case. Reconstructions requiring more than one general anesthetic were due to 4 of 39 (10%) postoperative complications. Mean operating time was 485 minutes.

CONCLUSIONS

For patients who need contralateral reduction mammoplasty or mastopexy for symmetry, performing these procedures and breast reconstruction simultaneously facilitates single-stage breast reconstruction in most patients.

Donor site morbidity following DIEP flap for breast reconstruction in Asian patients: Is it different?

BACKGROUND

Despite the decrease in donor-site morbidity with the advent of deep inferior epigastric artery perforator (DIEP) flap breast reconstruction, abdominal complications still occur. There have been few studies on donor morbidity considering the ethnic differences in the Asian population, as represented by a lower BMI with less redundant tissue and a tendency for poor scarring. In the present study, the authors investigated the incidence of abdominal complications and their risk factors following DIEP flap breast reconstruction in an Asian population.

PATIENTS AND METHODS

The authors conducted a retrospective review of DIEP flap based breast reconstructions performed in the past 5 years. Data regarding patient demographics, surgical details, and abdominal complications were collected from our prospectively maintained database and analyzed.

RESULTS

A total of 217 patients who underwent DIEP flap breast reconstruction were included. There were 51 abdominal complications (23.5%), including 18 delayed wound healing, 17 hypertrophic scarring, 12 seroma formation, and 8 abdominal bulges with no hernias. Secondary procedures were performed for the donor-site complications in 36 cases. Flap height was a significant risk factor for overall donor-site morbidity. Harvesting a bipedicle flap was significantly associated with abdominal fat necrosis and hypertrophic scarring. Harvesting a flap based on perforators from both rows was significantly associated with abdominal delayed wound healing and hypertrophic scarring.

CONCLUSIONS

DIEP flap breast reconstruction performed in Asian patients showed acceptable donor-site morbidity without significant complications. This study suggests that donor-site morbidity from harvesting a DIEP flap is comparable to that described in Western literatures.