Decision-making in DIEP and ms-TRAM flaps: The potential role for a combined laser Doppler spectrophotometry system

Laser Speckle Flowgraphy Can Support Intraoperative Assessment of Deep Inferior Epigastric Perforator Flap Blood Flow With Indocyanine Green

Background

Accurately evaluating cutaneous blood flow during the elevation of a deep inferior epigastric perforator (DIEP) flap may reduce postoperative complications in breast reconstruction surgery. This study examined whether laser speckle flowgraphy (LSFG) could be used to help objectively identify the safe areas of DIEP flaps.

Methods

Forty-eight patients who underwent unilateral breast reconstruction with a DIEP flap at Shinshu University Hospital between 2020 and 2024 were prospectively studied. During flap elevation, skin blood flow throughout the flap was measured using LSFG and compared with results obtained by indocyanine green (ICG) angiography. The cohort was also divided according to the number and location of perforators, and an intergroup comparison was performed according to LSFG readings.

Results

In all subjects, relative LSFG blood flow in zones 2 (89.1%) and 3 (87.9%) was comparable, whereas blood flow in zone 4 (72.8%) was significantly lower than in those areas (both P < 0.001). In the lateral row group, blood flow in zone 2 tended to be lower and in zone 3 tended to be higher than in the medial row group (zone 2: 82.6% versus 89.5%, zone 3: 93.6% versus 86.8%). LSFG values did not differ significantly in relation to perforator number. LSFG-determined blood flow in the stained side of the ICG-determined staining border was significantly higher than in the nonstained side (80.6% versus 71.4%, P < 0.001).

Conclusions

LSFG enables objective, noninvasive evaluation of safety margins in DIEP flaps that may support ICG angiography. Safe zones may vary depending on the location of the selected perforator.

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).

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.

[Increasing Safety in Microsurgical Breast Reconstruction - Technique and Technology]

Microsurgical reconstruction has established itself as a standard procedure in breast reconstruction as it permits creation of a natural and aesthetically appealing breast mound, even after modified radical mastectomy and radiation. In the past few decades numerous new free flap donor-sites have been described that permit an individualized approach to reconstruction, thus, resulting in a high level of patient satisfaction. Paralleling these technical innovations, the focus of microsurgical breast reconstruction has shifted from mere "flap success" to "aesthetic outcome", while also taking into account the respective donor-site morbidity. Here, the authors discuss contemporary developments in the field with a particular focus on surgical techniques and technologies that contribute to increasing the safety of microsurgical breast reconstruction.

Intraoperative Blood Flow Analysis of DIEP vs. ms-TRAM Flap Breast Reconstruction Combining Transit-Time Flowmetry and Microvascular Indocyanine Green Angiography

Background: Vascular patency is the key element for high flap survival rates. The purpose of this study was to assess and compare the blood flow characteristics of deep inferior epigastric perforator (DIEP) and muscle-sparing transverse rectus abdominis musculocutaneous (ms-TRAM) flaps for autologous breast reconstruction. Methods: This prospective clinical study combined Transit-Time Flowmetry and microvascular Indocyanine Green Angiography for the measurement of blood flow volume, vascular resistance, and intrinsic transit time. Results: Twenty female patients (mean age, 52 years) received 24 free flaps (14 DIEP and 10 ms-TRAM flaps). The mean arterial blood flow of the flap in situ was 7.2 ± 1.9 mL/min in DIEP flaps and 11.5 ± 4.8 mL/min in ms-TRAM flaps (p < 0.05). After anastomosis, the mean arterial blood flow was 9.7 ± 5.6 mL/min in DIEP flaps and 13.5 ± 4.2 mL/min in ms-TRAM flaps (p = 0.07). The arterial vascular resistance of DIEP flaps was significantly higher than that of ms-TRAM flaps. The intrinsic transit time of DIEP flaps was 52 ± 18 s, and that of ms-TRAM flaps was 33 ± 11 s (p < 0.05). The flap survival rate was 100%. One DIEP flap with the highest intrinsic transit time (77 s) required surgical revision due to arterial thrombosis. Conclusion: In this study, we established the blood flow characteristics of free DIEP and ms-TRAM flaps showing different blood flow rates, vascular resistances, and intrinsic transit times. These standard values will help to determine the predictive values for vascular compromise, hence improving the safety of autologous breast reconstruction procedures.

Safety of medical compression stockings in patients with diabetes mellitus or peripheral arterial disease

INTRODUCTION

Compression therapy is highly effective in the treatment of many venous diseases, including leg edema. However, its relevance in patients with peripheral arterial disease (PAD) or diabetes mellitus is critically discussed. The aim of the present study was to assess the influence of compression therapy on microperfusion and its safety in patients with PAD or diabetes mellitus.

RESEARCH DESIGN AND METHODS

A prospective analysis of 94 consecutive patients (44 patients with diabetes, 45 patients with PAD and 5 healthy controls) undergoing medical compression therapy was performed. Microperfusion was assessed by a combined method of white light tissue spectrometry and laser Doppler flowmetry under medical compression therapy (classes I and II), in different body positions (supine, sitting, standing and elevated position of the leg) and at different locations (great toe, lateral ankle and calf).

RESULTS

During the entire study, no compression-related adverse events occurred. Evaluation of microcirculation parameters (oxygen saturation of hemoglobin and flow) at the different locations and in sitting and standing positions (patients with diabetes and PAD) under compression therapy classes I and II revealed no tendency for reduced microperfusion in both groups. In contrast, in the elevated leg position, all mean perfusion values decreased in the PAD and diabetes groups. However, the same effect was seen in the healthy subgroup.

CONCLUSIONS

In consideration of the present inclusion criteria, use of medical compression stockings is safe and feasible in patients with diabetes or PAD. This study did not find relevant impairment of microperfusion parameters under compression therapy in these patient subgroups in physiologic body positions.

TRIAL REGISTRATION NUMBER

NCT03384758.

Enhancing Safety in Reconstructive Microsurgery Using Intraoperative Indocyanine Green Angiography

Intraoperative assessing and postoperative monitoring of the viability of free flaps is of high relevance in reconstructive microsurgery. Today different methods for the evaluation of tissue perfusion are known. Indocyanine Green angiography is an emerging technique among plastic surgeons with a broad scope of applications especially in microsurgical free flap transfer. We demonstrate the value and clinical application of this technique based on representative selected cases where Indocyanine Green angiography was used in microsurgical free flap transfers from different anatomic donor sites during the operation. Hereby perforator selection, flap tailoring, changes of blood flow and patency of anastomoses was judged and decision making was based on the angiographic findings. This method has proven to be valid, reproducible and easy to use. The application is not limited to the evaluation of skin perfusion, but is also applicable to muscle tissue or chimeric or composite flaps. Reliable judgement is especially given for the extent of arterially perfused tissue following complete flap dissection. Moreover, this real-time angiography revealed a high sensitivity for the detection of poorly perfused flap areas, thus supporting the conventional clinical judgement and reducing complications. In summary Indocyanine Green angiography has the potential to reduce flap related complications and to contribute to enhancing and extending the possibilities of free flap surgery.

Assessment of Tissue Perfusion Following Conventional Liposuction of Perforator-Based Abdominal Flaps

Background

The effect of liposuction on the perforators of the lower abdominal wall has been investigated in several studies. There are controversial results in the literature that have primarily demonstrated the number and patency of the perforators. The aim of this study was to determine the effect of liposuction on the perfusion of perforator-based abdominal flaps using a combined laser–Doppler spectrophotometer (O2C, Oxygen to See, LEA Medizintechnik).

Methods

Nine female patients undergoing classical abdominoplasty were included in the study. Perforators and the perfusion zones of the deep inferior epigastric artery flap were marked on the patient's abdominal wall. Flap perfusion was quantitatively assessed by measuring blood flow, velocity, capillary oxygen saturation, and relative amount of hemoglobin for each zone preoperatively, after tumescent solution infiltration, following elevation of the flap on a single perforator, and after deep and superficial liposuction, respectively.

Results

The measurements taken after elevation of the flap were not significantly different than measurements taken after the liposuction procedures.

Conclusions

The liposuction procedure does not significantly alter the perfusion of perforator-based abdominal flaps in the early period. The abdominal tissue discarded in a classic abdominoplasty operation can be raised as a perforator flap and has been demonstrated to be a unique model for clinical research.

The Angiosome Concept Evaluated on the Basis of Microperfusion in Critical Limb Ischemia Patients-an Oxygen to See Guided Study

OBJECTIVES

Aim of this clinical study was to evaluate the angiosome concept with regard to the microcirculation of the foot in patients with CLI and to evaluate its relevance by means of combined laser Doppler flowmetrie and white-light tissue spectrophotometry.

METHODS

Twenty-eight patients who underwent leg revascularization in the stage of CLI were prospectively examined. The microperfusion was assessed by light guided spectrophotometry. The measuring points were set according to the angiosome concept into direct and indirect revascularized areas of the foot. Investigations were performed pre and postinterventionally and after 4 and 12 weeks in baseline-position as well as in an elevated position of the leg.

RESULTS

Microcirculation parameters (oxygen saturation, blood flow, velocity) of the revascularized leg showed a significant increase in elevation and baseline position compared to the preoperative values in most analyses. No significant differences between the direct and indirect revascularized angiosome were apparent.

CONCLUSION

The light-guided spectrophotometry measurement proved to be feasible in terms of measuring changes in the microcirculation after leg revascularization. However, our data do not support the value of the "angiosome concept" concerning the individual changes in microperfusion of the foot in patients with CLI.

Quantifying Blood Flow in the DIEP Flap: An Ultrasonographic Study

Supplemental Digital Content is available in the text.

Background:

The maximum weight of tissue that a single perforator can perfuse remains an important question in reconstructive microsurgery. An empirically based equation, known as the flap viability index (FVI), has been established to determine what weight of tissue will survive on one or more perforators. The equation is FVI = Sum d(n)^4/W, where d is the internal diameter of each perforator and W is the final weight of the flap. It has been shown that if FVI exceeds 10, total flap survival is likely, but if under 10, partial flap necrosis is probable. The aim of this study was to measure absolute flow rates in deep inferior epigastric perforator (DIEP) flap pedicles and assess correlation with the determinants of the FVI, perforator diameter and flap weight.

Methods:

Color Doppler ultrasound was used to quantify arterial flow in 10 consecutive DIEP flap pedicles 24 hours after anastomosis.

Results:

In single-perforator DIEP flaps, flow rate was highly correlated with perforator diameter (r = 0.82, P = 0.01). Mean arterial flow rate was significantly reduced in DIEP flaps with 2 or more perforators (6 vs 38 cm³/min; P < 0.05).

Conclusions:

This study confirms that perforator size is a critical factor in optimizing blood flow in perforator-based free tissue transfer. Further research is required to understand the flow dynamics of perforator flaps based on multiple perforators. However, surgeons should be cognizant that a single large perforator may have substantially higher flow rates than multiple small perforators. Routine FVI calculation is recommended to ensure complete flap survival.

Meta-analysis of the safety and factors contributing to complications of MS-TRAM, DIEP, and SIEA flaps for breast reconstruction

BACKGROUND

Muscle-sparing transverse rectus abdominis myocutaneous (MS-TRAM), deep inferior epigastric perforator (DIEP), and superficial inferior epigastric artery (SIEA) flaps have been increasingly adopted for breast reconstruction. However, their safety, patient satisfaction with them, and factors contributing to complications are not well understood.

METHODS

PubMed, MEDLINE, EMBASE, and The Cochrane Library were searched to identify eligible studies for inclusion in our analysis. The complication rates of and patient satisfaction rates with the flaps were measured as the outcome, and factors contributing to complications and patient satisfaction were also studied. The data were extracted, and pooled relative risks (RRs) and 95 % confidence intervals (CIs) were calculated.

RESULTS

Thirteen studies involving 1,843 patients met the inclusion criteria. The results of the meta-analysis showed that patients with MS-TRAM had a higher rate of abdominal hernias (RR 2.354, 95 % CI 1.154-4.802, P = 0.019) and a lower rate of fat necrosis (RR 0.502, 95 % CI 0.347-0.727, P = 0.000) than patients with DIEP. In addition, there was no significant difference between MS-TRAM and DIEP with respect to other complications (P > 0.05), between MS-TRAM and DIEP with respect to patient satisfaction (P = 0.923), and between DIEP and SIEA with respect to complication rates (P = 0.377). The complication rates of MS-TRAM, DIEP, and SIEA were 25.6, 27.9, and 26.7 %, respectively. Diabetes mellitus (P = 0.078) influenced the complication rate of MS-TRAM, and obesity (P = 0.086) and diabetes mellitus (P = 0.110) were the potential factors correlated with complications with DIEP flaps.

CONCLUSION

There were no obvious differences in the overall incidence of complications between MS-TRAM and DIEP and between DIEP and SIEA. In addition, the patient satisfaction rates of MS-TRAM and DIEP were similar. However, MS-TRAM showed a higher rate of abdominal hernias and a lower rate of fat necrosis than DIEP. Obesity and diabetes mellitus were potential factors associated with the incidence of complications. Additional multicenter, large-sample-size, randomized controlled trials with long-term follow-up visits are necessary.

LEVEL OF EVIDENCE III

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Cyclic negative pressure wound therapy: an alternative mode to intermittent system

The purpose of this study was to develop and test a novel mode of negative pressure wound therapy (NPWT) that minimises pain while preserving the efficacy in wound healing. A porcine model was used in this study. Wounds were generated in animals and treated with either simple dressing or various treatment modes of NPWT. The wound volume, perfusion level and vasculature status were analysed and compared among different groups. Clinical application was performed to evaluate the level of pain occurring when negative pressure is applied. Among the NPWT groups, the Cyclic-50 group showed most decrement in wound volume, even though statistical relevance was not found (P = 0·302). The perfusion level was significantly increased in the Cyclic-50 group compared with the Intermittent group (P < 0·001) and the Cyclic-100 group (P = 0·004). Evaluation of blood vessel formation revealed that the Cyclic-50 group showed the highest number of vasculature with statistical significance (P < 0·001). In clinical application, the cyclic group showed significant decrease in pain compared with the intermittent group (P = 0·001). The cyclic NPWT mode decreased patient discomfort while maintaining superior wound healing effects as the intermittent mode.

Zonal perfusion patterns in pedicled free-style perforator flaps

INTRODUCTION

Local perforator flaps have become a standard procedure in reconstructive surgery. They allow the transfer of large tissue units with minimal donor-site morbidity. However, clinical studies on flap perfusion changes over time are lacking. The aim of this study was to investigate the perfusion of free-style single perforator flaps with an eccentrically located main perforator by combined laser Doppler spectrophotometry.

PATIENTS AND METHODS

Ten patients (six male, four female, 29-71 years) were included in this prospective clinical study. All flaps were based on one perforator. Flaps were harvested from the trunk (n = 6) or the proximal upper or lower extremity (n = 4). Flap perfusion was assessed using a combined laser Doppler spectrophotometry (CLDS) device (O2C, Oxygen to See, LEA Medizintechnik, Giessen, Germany) at days 0, 1, 7 and 14 in different zones.

RESULTS

Flap dimensions were 18.6 ± 4.7 × 7.2 ± 1.6 cm. Two flaps developed minor tip necroses (<10%), eight flaps survived completely. CLDS proved to be very sensitive for the detection of regional perfusion problems. A considerable perfusion gradient was observed at days 0 and 1. Here, reduced blood flow and post-capillary oxygen saturations were found at the tip when compared to the region above main perforator (RAMP). Blood flow remained stable proximally while it improved significantly from day 1 to 14 at the tip region.

CONCLUSION

CLDS is an effective method for objective evaluation of flap perfusion. Although distal flap perfusion is diminished initially, the majority of perforator flaps with eccentrically located perforators survive completely. Obviously, flap perfusion improved between days 1 and 14. This clinical finding might be explained by reorganisation of the vascular system with opening of so-called connecting or choke vessels. This knowledge might influence decision making in perforator flap surgery.