Laser-assisted Indocyanine Green Fluorescence Angiography Research Articles

Preconditioning with Foam-mediated External Suction on Flap Microvasculature and Perfusion in a Rodent Model.

Background:Foam-mediated external suction (FMES) has previously shown to improve tissue microcirculation. We hypothesized that preconditioning fasciocutaneous perforator flaps with FMES would augment perfusion and demonstrate greater capillary recruitment.Methods:Gluteal perforator flaps were designed on sixteen 400 g rats. Continuous FMES at −125 mm Hg was applied on one side (intervention) to precondition tissue for 5 days, with the contralateral side as a paired control. In group A, we assessed changes following pretreatment, after surgery, and 7 days postprocedure, and in group B, we evaluated changes during preconditioning alone. In group A (N = 8), control and intervention flaps were assessed using laser-assisted indocyanine green fluorescence angiography. In group B, flap regions were assessed using 4-dimensional computed tomographic angiography. All flaps were analyzed for microvessel density using micro–computed tomography and histological assessment using hematoxylin and eosin and CD3 immunohistochemistry.Results:Thirty-two flaps were included in this study (N = 16 intervention and matched controls). Four-dimensional computed tomographic angiography demonstrated 17% greater tissue perfusion in preconditioned flaps (mean, 78.7 HU; SD, 8.8) versus controls (mean, 67.3 HU; SD, 15.7; P < 0.01). Laser-assisted indocyanine green fluorescence angiography showed a 30% higher mean absolute intensity in preconditioned flaps versus controls (P < 0.01). Postsurgery mean absolute intensity in preconditioned flaps remained 21% higher than in controls (P = 0.03). Preconditioned flaps demonstrated a 2-fold increase in mean vessel volume of 9.1 mm3 (SD, 7) versus 4.5 mm3 (SD, 3) in controls (P = 0.04); there was a 33% higher mean area fraction of CD31 in preconditioned flaps, 3.9% (SD, 3) versus 2.9% (SD, 3) in controls (P = 0.03).Conclusion:FMES preconditioning has the potential to augment vascularity of tissue for flap harvest; however, further experimental studies are required to optimize strategies and evaluate long-term effects for clinical applications.

Intraoperative Assessment of DIEP Flap Breast Reconstruction Using Indocyanine Green Angiography: Reduction of Fat Necrosis, Resection Volumes, and Postoperative Surveillance.

This study aims to characterize the effect of laser-assisted indocyanine green fluorescence angiography on fat necrosis and flap failure in deep inferior epigastric artery perforator (DIEP) flap breast reconstruction. A retrospective review was performed on 1000 free flaps for breast reconstruction at a single center from 2010 to 2017. Indocyanine green angiography was used after completion of recipient-site anastomoses to subjectively assess for areas of hypoperfusion. A multivariable logistical analysis was conducted with 24 demographic and surgical factors and their effects on fat necrosis and flap failure. Five hundred six DIEP flaps were included in the statistical analyses. Thirteen percent of flaps had fat necrosis. Indocyanine green angiography was used for 200 flaps and was independently associated with a decrease in the odds of fat necrosis (OR, 0.38; p = 0.004). There was no reduction in flap failure rates when using indocyanine green angiography (OR, 1.15; p = 0.85). However, there was a decrease in flap loss with increasing venous coupler diameter (OR, 0.031 per 1-mm increase; p = 0.012). The 84.9-g higher weight of resected tissue before inset without indocyanine green angiography versus the weight of the tissue resected with indocyanine green angiography was statistically significant (p = 0.01). Per single incident of fat necrosis, our cohort underwent an additional 0.69 revision procedures, 1.22 imaging studies, 0.77 biopsies, and 1.7 additional oncologic office visits. Intraoperative indocyanine green fluorescence angiography decreases the odds of fat necrosis, saves volume when flap trimming at inset, and can significantly reduce the postoperative surveillance burden in DIEP-based breast reconstruction. Therapeutic, III.

Nipple sparing mastectomy and direct to implant breast reconstruction, validation of the safe procedure through the use of laser assisted indocyanine green fluorescent angiography

Nipple sparing mastectomy (NSM) is a psychologically effective and oncological safe procedure followed by immediate breast reconstruction. Between January 2015 and September 2015 the authors conducted a retrospective review of 40 patients divided into two groups depending on breast volume and weight of mastectomy: group A, 20 patients with small breast; group B, 20 patients with medium breast for nipple sparing mastectomy and direct to implant (DTI) breast reconstruction using strict patient selection and a standardized surgical technique. The nipple areola complex/flap viability were analysed intraoperatively through the use of laser assisted indocyanine green (ICG) fluorescent angiography. A total of 44 procedures were followed-up for 24 months. Nineteen patients were assisted in DTI breast reconstruction by acellular dermal matrix (ADM) for inferior/lateral part of the implant coverage. Encouraging results are presented with a unique case of implant failure. We report our retrospective experience corroborated by intraoperative laser assisted ICG fluorescent angiography to demonstrate the safety and reliability of the oncoplastic procedure proposed. We also advocate the central role of oncoplastic surgeon as "one man band" to manage breast cancer from the oncological procedure to the breast reconstruction.

Quantitative analysis of facial soft tissue perfusion during hypotensive anesthesia using laser-assisted indocyanine green fluorescence angiography

The aim of this study was to quantitatively evaluate the efficacy of induced hypotensive anesthesia in decreasing facial soft tissue perfusion during orthognathic surgery using laser-assisted indocyanine green fluorescence angiography. This retrospective study involved the evaluation of 16 patients who underwent orthognathic surgery. Data collection included facial tissue perfusion of the bilateral cheeks and chin at normotension and with pharmacologically induced hypotensive anesthesia. There were statistically significant differences in the facial tissue perfusion at normal and depressed levels of blood pressure (P<0.001). This study used an objective measure to demonstrate the long-standing belief that hypotensive anesthesia is efficacious in reducing tissue perfusion in the surgical field. The data suggest that pharmacologically depressing the level of mean arterial pressure by 18% may result in a 41–52% decrease in facial soft tissue perfusion. This study reports a novel method of quantitative analysis.

Laser-assisted indocyanine green angiography in implant-based immediate breast reconstruction: a retrospective study

Objective: Necrosis in implant-based immediate breast reconstruction is a feared complication. Accurate evaluation of mastectomy skin flaps per-operatively is necessary to decrease this risk. The present study is the first in Scandinavia to review the effects of perioperative evaluation with laser-assisted indocyanine green fluorescence angiography (LA-ICGA).Method: A retrospective review was performed using data from the electronic patient record at the Department of Plastic and Breast Surgery at Aarhus University Hospital in Denmark on all patients who underwent implant-based skin-sparing immediate breast reconstruction with ADM in the time period March 2012 to October 2015. A total of 92 patients undergoing 128 breasts reconstructions were included in the study. An evaluation of complications before and after the implementation of LA-ICGA was performed.Results: No significant difference in necrosis rates requiring surgical revision (p = .411) or conservative treatment (p = .149) in patients undergoing implant-based immediate breast reconstruction were found.Conclusion: Our results differ from previously published studies in that no beneficial effect on necrosis rates of was found after implementing LA-ICGA, possibly due to our limited sample size.

Abstract: Vascular Anatomy of Facial Units for Vascularized Composite Tissue Transplantation Design in a Large Animal Model: An in-Vivo and Radiological Study

INTRODUCTION: A large animal model for composite face transplantation is necessary to better understand the immunologic processes and nerve regeneration. Current porcine models of facial transplantation fail to include all major branches of the facial nerve, and have not demonstrated long-term survival.1,2 A better understanding and detailed evaluation of vascular anatomy and microvascular territories in facial subunits and bone can help effectively develop a reliable porcine composite tissue flap model for experimental reconstructive or transplantation studies. METHODS: Eleven 10kg domestic pigs were used for in-vivo studies. Vascular anatomy was assessed by Intra-operative anatomical dissections of 11 hemi-facial composite tissue flaps including the auricle. In addition Computed Tomographic Angiography (CTA) and Laser-assisted Indocyanine Green Fluorescence Angiography (LA-ICGFA) were used to assess vascular architecture preoperatively and flap perfusion. In addition, 8 cadaveric pigs were used for selective angiography of branches of the external carotid artery using a barium sulfate and latex mixture to provide detailed qualitative and quantitative analysis of the vascular territories using ultra-high resolution 3D CTA followed by a detailed anatomical dissection. Perforator distributions in facial subunits and the relationship of vascular territories to the facial nerve branches were documented. RESULTS: A composite tissue flap of the hemi-face including the auricle was elevated and auto-transplanted in eleven 2 months old domestic pigs. Three pigs underwent preoperative CTA. We demonstrated two principal vessels supplying the hemifacial tissues: Internal maxillary artery (IMA) and superficial temporal artery (STA), with less significant contribution from the facial artery. Use of 3D volume rendering of the CTAs and the anatomical dissections demonstrated the vasculature and potential angiosomes of dominant and minor branches from the external carotid artery. We have been able to categorize facial subunit vascularity to delineate safe vascular territories for flap design in facial transplantation or reconstructive surgery. CONCLUSION: We describe a new swine facial transplantation model with successful outcomes and reliable vascularity confirmed with anatomic, in-vivo CTA studies. Novel detailed vascular injection studies provide understanding of 3D vascular territories paramount to flap design, therefore enabling successful long-term modeling of hemi-facial composite tissue transplantation. DISCLOSURE/FINANCIAL SUPPORT:None of the authors has a financial interest in any of the products, devices, or drugs mentioned in this manuscript. REFERENCES: 1. Kuo, Y. R., Shih, H. S., Lin, C. C., et al. (2009). Swine hemi-facial composite tissue allotransplantation: a model to study immune rejection. Journal of Surgical Research, 153(2), 268–273. 2. Gordon, C. R., Murphy, R. J., Coon, D., et al. (2014). Preliminary development of a workstation for craniomaxillofacial surgical procedures: introducing a computer-assisted planning and execution system. The Journal of craniofacial surgery, 25(1), 273.

Application of Laser-Assisted Indocyanine Green Fluorescent Angiography for the Assessment of Tissue Perfusion of Anodermal Advancement Flaps

Application of Laser-Assisted Indocyanine Green Fluorescent Angiography for the Assessment of Tissue Perfusion of Anodermal Advancement Flaps

The Application of Laser-Assisted Indocyanine Green Fluorescent Dye Angiography in Microsurgical Breast Reconstruction

The benefits of laser-assisted indocyanine green fluorescence angiography have previously been demonstrated in cardiac surgery. The purpose of this study was to determine the value of this technology in microsurgical breast reconstruction. Intraoperative laser-assisted indocyanine green fluorescence angiography was performed on all microsurgical breast reconstruction cases (deep inferior epigastric perforator flap or free transverse rectus abdominus muscle flap) during the study period. Ten consecutive free tissue transfer autologous breast reconstructions were performed on 8 women. In four cases, imaging demonstrated flow or perfusion deemed "marginal" or "poor" by the operating surgeons. In three of these cases, one involving poor arterial inflow, one of poor venous outflow, and one of poor perfusion of a mastectomy flap, the intraoperative plan was adjusted accordingly and follow-up imaging demonstrated improvement. In the fourth case, no adjustment was made at operation. However this patient required a return to the operating room for venous congestion of the flap, which was corrected without sequela. Overall flap survival was 100%. We concluded that laser-assisted indocyanine green fluorescence angiography appears to provide important information that has helped guide intraoperative decision making in our series.