Intraoperative Fluorescent Angiography Research Articles

First experience of applying domestic video fluorescent equipment for visualization and blood flow evaluation of the parathyroid glands

In recent years, predictive methods for assessing the preservation of the parathyroid glands have been actively implemented. The article describes the first experience of evaluating the blood supply of the parathyroid glands by quantitative determination of the indocyanine green (ICG) accumulation index in real time in 6 patients before and after a thyroidectomy with central neck lymph node dissection for papillary thyroid cancer. Intraoperative fluorescent angiography was performed by using domestic equipment with a fluorescent module, as well as by using a domestic medication of ICG. Intraoperative values of the ICG accumulation index were compared with the levels of ionized calcium and parathyroid hormone perioperatively. No clinical manifestations of hypocalcemia were detected in the postoperative period. The obtained results showed the informativeness of the numerical assessment of the intensity of ICG fluorescence. The evaluation of the distribution (accumulation) of ICG has prospects for practical application in thyroid surgery in the formation of tactics for preserving the parathyroid glands and predicting postoperative hypoparathyreosis.

Assessment of Flap Viability for Complex Transmetatarsal Amputation Using Indocyanine Green Fluorescent Angiography: A Case Study.

Despite advancements in the treatment of diabetic patients with "at-risk" limbs, minor and major amputations remain commonplace. The diabetic population is especially prone to surgical complications from lower extremity amputation because of comorbidities such as renal disease, hypertension, hyperlipidemia, microvascular and macrovascular disease, and peripheral neuropathy. Complication occurrence may result in increases in hospital stay duration, unplanned readmission rate, mortality rate, number of operations, and incidence of infection. Skin flap necrosis and wound healing delay secondary to inadequate perfusion of soft tissues continues to result in significant morbidity, mortality, and cost to individuals and the health-care system. Intraoperative indocyanine green fluorescent angiography for the assessment of tissue perfusion may be used to assess tissue perfusion in this patient population to minimize complications associated with amputations. This technology provides real-time functional assessment of the macrovascular and microvascular systems in addition to arterial and venous flow to and from the flap soft tissues. This case study explores the use of indocyanine green fluorescent angiography for the treatment of a diabetic patient with a large dorsal and plantar soft-tissue deficit and need for transmetatarsal amputation with nontraditional rotational flap coverage. The authors theorize that the use of indocyanine green may decrease postoperative complications and cost to the health-care system through fewer readmissions and fewer procedures.

Impact of N-Acetyl-Cysteine on Ischemic Stumps Following Major Lower Extremity Amputation: A Pilot Randomized Clinical Trial.

To evaluate the impact of N-acetyl-cysteine (NAC) on amputation stump perfusion and healing in patients with critical limb-threatening ischemia (CLTI). Patients with CLTI are at increased risk of poor amputation site healing leading to increased procedure-associated morbidity. In a pilot, double-blind, placebo-controlled, randomized controlled trial, patients with CLTI undergoing major elective lower extremity amputation were randomized 1:1 to intravenous NAC (1200 mg twice-daily) or placebo for up to 5 days postoperatively. Primary outcomes were change in stump perfusion at postoperative day 3 (POD3) and POD5, and healing at POD30. Stumps were serially evaluated for wound healing, and tissue perfusion was evaluated using noninvasive laser-assisted fluorescent angiography. Thirty-three patients were randomized to NAC (n = 16) or placebo (n = 17). Thirty-one patients were eligible for intent-to-treat analysis (NAC14; placebo17). Twenty patients (NAC7; placebo13) had amputation stump perfusion defects at POD0 and were considered high-risk for poor healing. Intent-to-treat analysis revealed no significant differences between treatment groups. Subgroup analysis of high-risk patients revealed differences in stump perfusion defect size (NAC-0.53-fold, placebo +0.71-fold; 95% confidence interval -2.11 to-0.35; P < 0.05) and healing (NAC [100%], placebo [46%]; P < 0.01) between study treatments. Postoperative NAC administration may improve amputation stump perfusion and healing in patients with CLTI and tissue perfusion defects at the time of amputation. Intraoperative laser-assisted fluorescent angiogra-phy may help surgeons identify high-risk patients with stump perfusion defects and provide early adjunctive interventions. Future studies can further explore the therapeutic benefits of NAC in the healing and perfusion of other surgical operative sites in high-risk individuals. clinicaltrials.gov, Identifier: NCT03253328.

Intraoperative angiography imaging correlates with wound complications following soft tissue sarcoma resection.

For soft tissue sarcoma patients receiving preoperative radiation therapy, wound complications are common and potentially devastating. The purpose of this study was to assess the feasibility of intraoperative indocyanine green fluorescent angiography (ICGA) as a predictor of wound complications in these patients. A consecutive seriesof patients with soft tissue sarcoma of the extremities or pelvis who received neoadjuvant radiation and a subsequent radical resection received intraoperative ICGA with the SPY PHI device (Stryker Inc.) at the time of closure. Retrospective analysis of fluorescence signal along multiple points of the wound length was performed and quantified. The primary endpoint was wound complication, defined as delayed wound healing or wound dehiscence, within 3 months of surgery. Fourteenpatients with preoperative irradiated soft tissue sarcoma were consecutively imaged. There were six patients with wound complications classified as "aseptic" in five cases. Using the ICGA, blinded surgeons correctly predicted wound complications in 75% of cases. During the inflow phase, a mean ratio of normal of 0.62 maximized the area under the curve (AUC = 0.90) for predicting wound complications with a sensitivity of 100% and specificity of 77.4%. During the peak phase, a mean ratio of normal of 0.55 maximized the AUC (0.95) for predicting wound complications with a sensitivity of 88.9% and a specificity of 100%. Intraoperative use of ICGA may help to predict wound complications in patients undergoing resection of preoperatively irradiated soft tissue sarcomas of the extremities and pelvis.

Comparison of Detection of Superior Gluteal Artery Perforator by Indocyanine Green Fluorescence Near-Infrared ANGIOGRAPHY and Handheld Acoustic Doppler Sonography for Reconstruction of Sacral Pressure Injury.

Aims: Pressure injury is a gradually increasing disease in the aging society. The reconstruction of a pressure ulcer requires a patient and surgical technique. The patients were exposed to the radiation risk under other ways of detection of perforators such as computed tomographic angiography and magnetic resonance angiography. Here, we compared two radiation-free methods of a superior gluteal artery perforator (SGAP), flap harvesting and anchoring. One is the traditional method of detecting only handheld acoustic Doppler sonography (ADS) (Group 1). The other involves the assistance of intraoperative indocyanine green fluorescent near-infrared angiography (ICGFA) and handheld ADS (Group 2). Materials and Methods: This is a single-center, retrospective, observational study that included patients with sacral pressure injury grades III and IV, who had undergone reconstructive surgery with an SGAP flap between January 2019 and January 2021. Two detection methods were used intraoperatively. The main outcome measures included the operative time, estimated blood loss, major perforator detection numbers, wound condition, and incidence of complications. Results: Sixteen patients underwent an SGAP flap reconstruction. All patients were diagnosed with grade III to IV sacral pressure injury after a series of examinations. Group 1 included 8 patients with a mean operative time of 91 min, and the mean estimated blood loss was 50 mL. The mean number of perforators was 4. Postoperative complications included one wound infection in one case and wound edge dehiscence in one case. No mortality was associated with this procedure. The mean total hospital stay was 16 days. Group 2 included 8 patients with a mean operative time of 107.5 min, and the mean estimated blood loss was 50 mL. The mean number of perforators was 5. Postoperative complications included one wound infection. No mortality was associated with this procedure. The mean total hospital stay was 13 days. Conclusions: The combination of detection of the SGAP by ICGFA and handheld ADS for the reconstruction of a sacral pressure injury provides a more accurate method and provides the advantage of being radiation-free.

Multispectral Imaging Using Fluorescent Properties of Indocyanine Green and Methylene Blue in Colorectal Surgery-Initial Experience.

Introduction: Image-guided surgery is becoming a new tool in colorectal surgery. Intraoperative visualisation of different structures using fluorophores helps during various steps of operations. In our report, we used two fluorophores—indocyanine green (ICG), and methylene blue (MB)—during different steps of colorectal surgery, using one camera system for two separate near-infrared wavelengths. Material and methods: Twelve patients who underwent complex open or laparoscopic colorectal surgeries were enrolled. Intravenous injections of MB and ICG at different time points were administered. Visualisation of intraoperative ureter position and fluorescent angiography for optimal anastomosis was performed. A retrospective analysis of patients treated in our departments during 2020 was performed, and data about ureter injury and anastomotic site complications were collected. Results: Intraoperative localisation of ureters with MB under fluorescent light was possible in 11 patients. The mean signal-to-background ratio was 1.58 ± 0.71. Fluorescent angiography before performing anastomosis using ICG was successful in all 12 patients, and none required a change in position of the planned colon resection for anastomosis. The median signal-to-background ratios was 1.25 (IQR: 1.22–1.89). Across both centres, iatrogenic injury of the ureter was found in 0.4% of cases, and complications associated with anastomosis was found in 5.5% of cases. Conclusions: Our study showed a substantial opportunity for using two different fluorophores in colorectal surgery, whereby the visualisation of one will not change the possible quantification analysis of the other. Using two separate dyes during one procedure may help in optimisation of the fluorescent properties of both dyes when using them for different applications. Visualisation of different structures by different fluorophores seems to be the future of image-guided surgery, and shows progress in optical technologies used in image-guided surgery.

The use of indocyanine green fluorescence to define bowel microcirculation during laparoscopic surgery for acute small bowel obstruction.

Although there is growing evidence to support the feasibility of a minimally invasive approach for acute small bowel obstruction, the inability to adequately evaluate compromised bowel segments has been cited as a major limitation. The aim of this work is to report a novel application of extemporaneous indocyanine green (ICG) fluorescence to assess bowel viability where there is a concern for ischaemic damage. After the cause of obstruction has been identified and resolved, and where there are dubious signs of bowel ischaemia present, fluorescent selective angiography is undertaken. The segment of bowel in question is observed under both normal and fluorescent light to assess local microcirculation. The adequacy of both the arterial supply and the venous drainage is thus appraised to define bowel viability. Among 71 patients who have undergone surgery for acute small bowel obstruction with a laparoscopic approach, seven received extemporaneous ICG fluorescence assessment of bowel viability. Different presentations with their relevant management are described. Selective use of intraoperative fluorescent angiography may overcome some of the intrinsic limitations of laparoscopy in assessing bowel viability during surgery for acute small bowel obstruction.

Intraoperative fluorescent angiography with indocyanine green in surgery of peripheral nerve injuries

Despite the widespread introduction of microsurgical techniques in peripheral nerve surgery, a relatively high percentage of unsatisfactory results remains. Often, when treating patients with traumatic neuropathies, the surgeon faces the problem of diastasis between the ends of the damaged nerve. As a rule, in the presence of diastasis greater than 5 cm, it is recommended to perform inter-bundle autoneuroplasty. However, overcoming diastasis less than 5 cm may be accompanied by tension of the nerve trunk, which leads to a violation of its blood supply. In this case, the outcome of the intervention may be unsatisfactory, despite the operation performed perfectly from a technical point of view. An important factor of the outcome of surgical treatment of neuropathies of various origins is the preservation of adequate blood supply to the nerve trunk in the intraoperative period. In order to assess the blood flow in the nerve trunk, the possibility of using intraoperative fluorescent angiography for reconstructive surgical interventions on nerves was considered. In patients with a complete anatomical break of the large nerve trunk, at the moment of overcoming diastasis, intraoperative angiography of the nerve trunk was performed by intravenous administration of indocyanine green, with simultaneous registration of the tension force with which the nerve trunk was affected. In addition, fluorescent angiography was performed after the restoration of the integrity of the nerve trunk, thus assessing the safety, adequacy and effectiveness of blood flow in it. It was found that intraoperative angiography is an accessible and easily implementable technique to determine the safety and, not least, the adequacy and effectiveness of the blood flow in the nerve trunk, to study the mechanisms of compensation of blood supply to the nerve after microsurgical epineural suture, and to assess the quality of matching the stumps of the nerve axis, preventing the possibility of «torsion».

Breast Reconstruction and Nipple-Sparing Mastectomy: Technical Modifications and Their Outcomes Over Time at an Academic Breast Center.

Superior aesthetic outcomes can be achieved with mastectomy techniques that maximize breast envelope preservation and maintain the nipple-areolar complex. This is the impetus for the popularization of the nipple-sparing mastectomy (NSM). Nipple-sparing mastectomy is a challenging procedure due to potential ischemia of the mastectomy flap (which includes the nipple-areolar complex) and the risk of incomplete oncologic resection. We review our experience with NSM, identify technique modifications used over time, and evaluate reconstructive outcomes of NSM and its modifications. A retrospective review of consecutive patients with NSM and breast reconstruction over an 8-year period was completed. Fifty-five patients underwent 95 NSMs. Indications included invasive and in situ cancer, atypical ductal hyperplasia, and risk reduction. In the first 4 years of experience, the most frequently used NSM incision was radial (lateral) whereas use of a variety of incision patterns was noted in the second 4 years. Overall NSM and breast reconstruction complication rate for the entire study period was 50.9% and included a full-thickness mastectomy skin flap necrosis/nipple necrosis rate of 8.4%. In situ cancer of the nipple was identified in 3.2% of the patients, and 1 patient had locoregional recurrence. Overall complication rate was lower in the second 4 years of experience with NSM and reconstruction. One third of the patients underwent intraoperative fluorescent angiography (FA) to assess mastectomy skin perfusion before reconstruction start. Of the patients who had FA due to perfusion concerns, more than 70% of studies demonstrated poor perfusion and 83.3% of these patients had reconstruction delayed based on these results. Immediate, implant-based reconstruction was performed most commonly. An average of 2.66 procedures were required to achieve reconstruction completion, and 92.4% of the patients who sought reconstruction achieved completion. At our institution, NSM use is increasing, NSM incision pattern types used are expanding, and complication rates are decreasing. Immediate, implant-based reconstruction is most commonly used in combination with NSM at our institution. Fluorescent angiography is used to assess mastectomy skin perfusion and likely limits mastectomy complication effects on reconstruction. Despite the occurrence of complications, most patients will complete the breast reconstruction process.

ASO Author Reflections: Usage of Intraoperative Fluorescent Angiography to Predict Wound Healing Complications After Salvage Laryngectomy.

ASO Author Reflections: Usage of Intraoperative Fluorescent Angiography to Predict Wound Healing Complications After Salvage Laryngectomy.

Intraoperative angiography with indocyanine green to assess anastomosis perfusion in patients undergoing laparoscopic colorectal resection: results of a multicenter randomized controlled trial.

Insufficient vascular supply is one of the main causes of anastomotic leak in colorectal surgery. Intraoperative indocyanine-green (ICG) angiography has been shown to provide information on tissue perfusion, identifying a well-perfused location for colonic and rectal transections, and thus possibly reducing the leak rate. Aim of this study was to evaluate the usefulness of intraoperative assessment of anastomotic perfusion using ICG angiography in patients undergoing left-sided colon or rectal resection with colorectal anastomosis. This randomized trial involved 252 patients undergoing laparoscopic left-sided colon and rectal resection randomized 1:1 to intraoperative ICG or to subjective visual evaluation of the bowel perfusion without ICG. The primary aim was to assess whether ICG angiography could lead to a reduction in anastomotic leak rate. Secondary outcomes were possible changes in the surgical strategy and postoperative morbidity. After randomization, 12 patients were excluded. Accordingly, 240 patients were included in the analysis; 118 were in the study group, and 122 in the control group. ICG angiography showed insufficient perfusion of the colic stump, which led to extended bowel resection in 13 cases (11%). An anastomotic leak developed in 11 patients (9%) in the control group and in 6 patients (5%) in the study group (p = n.s.). Intraoperative ICG fluorescent angiography can effectively assess vascularization of the colic stump and anastomosis in patients undergoing colorectal resection. This method led to further proximal bowel resection in 13 cases, however, there was no statistically significant reduction of anastomotic leak rate in the ICG arm. ClinicalTrials.gov NCT02662946.

How to reduce surgical complications in rectal cancer surgery using fluorescence techniques.

Anastomotic leakage (AL) is a serious complication in colorectal surgery leading to significant morbidity and mortality. Progressively lower anastomoses are associated with a greater leak rate. Adequate bowel perfusion has been stressed as one of the key elements for suture healing. Currently, there is no widespread method to assess and quantify the perfusion of gastrointestinal anastomoses intraoperatively, besides the subjective evaluation by the surgeon. The aim of this paper is to describe the basis of Indocyanine Green (ICG) fluorescence guided surgery applied to assessment of bowel perfusion and to highlight studies on the use of fluorescence angiography (FA) in laparoscopic rectal surgery. ICG fluorescence guided surgery has increasingly been used as a tool for intraoperative diagnostics to assess microperfusion and viability of tissues by means of a real-time FA; this technique has achieved the role of major contribution to intraoperative decision making during surgical procedures, especially in order to assess bowel perfusion before anastomosis creation in colorectal surgery. Several studies in literature already reported that ICG FA as a feasible technique to decrease AL rate in colorectal surgery; to date no randomized controlled trials have been completed but large series and prospective studies that focus on fluorescence perfusion assessment in rectal surgery have been published. Real time intraoperative ICG fluorescent angiography (FA) is a safe and feasible technique to guide the surgeon in intraoperative decision-making process. ICG FA seems to reduce AL rates following rectal surgery for cancer. However large well-designed RCTs are needed to provide evidence for its routine use.

Prevention of colorectal anastomotic leakage by using of intraoperative fluorescent angiography: prospective trial data

To evaluate the effect of intraoperative fluorescent angiography on the incidence of colorectal anastomosis failure. Prospective, non-comparative study included 52 patients with rectal or sigmoid cancer who underwent surgery with stapled colorectal anastomosis. Intraoperative fluorescent angiography with indocyanine green was performed to determine colon perfusion. All patients underwent proctography with water-soluble contrast agent in 6-8 days after surgery in order to determine anastomotic leakage. Fluorescent angiography was followed by changed volume of proximal colectomy in 14 (27%) patients due to inadequate blood supply of intestinal wall at previous surgical level. Additionally, 1-5 cm of intestinal wall were excised. Postoperative anastomotic leakage occurred in 3 (5.8%) patients. Fluorescent angiography with indocyanine green is accompanied by reduced incidence of anastomotic failure in colorectal suregry.

Improving Outcomes for Lower Extremity Amputations Using Intraoperative Fluorescent Angiography to Predict Flap Viability.

Nearly 25% of vascular surgery patients operated on for peripheral vascular disease are readmitted within 30 days. Development of adjuncts to minimize wound complications remains an area of great interest. Here, we present our experience with intraoperative fluorescent angiography (IFA) as a tool to predict skin flap viability following lower extremity amputations (LEAs). Experience with IFA using indocyanine green (ICG) dye was reviewed retrospectively at a single institution. Records of patients undergoing LEA with use of IFA by 2 vascular surgeons from 2013 to 2014 were reviewed. Absolute and relative tissue perfusion values were evaluated for sensitivity and specificity in regard to skin flap viability. Thirteen patients with a mean age of 70.5 years (standard deviation [SD] = 12.0, range: 49-93 years) underwent 17 amputations. Indications included rest pain, tissue gangrene, and vascular disease unsuitable for revascularization. Amputation levels included toe (23%), transmetatarsal (18%), below knee (41%), and above knee (18%). Six (35%) amputations required revision with a mean time-to-revision of 26.1 days (SD = 19.9, range: 9-61 days). Of these revisions, 14 (83%) patients proceeded to a proximal-level amputation. Mean follow-up was 235 days (SD = 148, range: 5-448 days), and IFA was used in all cases. Absolute perfusion values (APVs) between 5 and 9 displayed sensitivity and specificity of 50% and 64%, respectively. Additionally, a relative perfusion value (RPV) of ≤31% displayed 100% sensitivity and specificity. Sensitivity and specificity fell to 83% at a relative perfusion of ≤27% and ≤35%, respectively. IFA during LEA is safe and easily performed by the vascular surgeon. The RPVs as a predictor of skin flap viability correlate well with those reported in breast reconstructive surgery. Unfortunately, APVs fail to support any predication for flap failure or success. Patient comorbidities and intraoperative variables such as vasopressor use may contribute to this finding.

Determining the Trimming Layer in Breast Reconstruction with a Free TRAM Flap Using Intraoperative Video-angiography.

Summary:In breast reconstruction using a free transverse rectus abdominis myocutaneous or deep inferior epigastric perforator flap, the trimming process for the flap area, which is usually the upper portion of the reconstructed breast, is critical to creating a natural-looking breast. In this study, we investigated which subcutaneous fat layer of the abdominal flap benefited most from a well-maintained blood supply during the trimming process using intraoperative fluorescent angiography system in a cross-sectional view of the elevated abdominal flap. We concluded that, for cosmetic purposes, the deep subcutaneous fat layer (beneath Scarpa’s fascia) should be trimmed first to minimize fat necrosis due to fat ischemia.

Use of fluorescent angiography with indocyanine green for prediction of hypocalcemia development after thyroidectomy

Introduction. The future of thyroid gland fast-track surgery depends largely on early hypocalcemia prediction. We describe our experience of using intraoperative indocyanine green fluorescent angiography (IGFA) of parathyroid glands to access their function in the early postoperative period. The study objective is to evaluate the possibility of prediction of early postoperative hypocalcemia after thyroidectomy using intraoperative indocyanine green fluorescent angiography. Materials and methods. Thirty five (35) patients with benign and malignant thyroid tumors eligible for thyroidectomy were included in the study. Intraoperative IGFA was performed using the SPY SP2000 (Novadaq Technologies Inc., Canada) device and visual assessment of vascularization of the parathyroid glands. The glands without fluorescence were considered ischemic. Ionized calcium test was performed 4, 8, and 18–24 hours after the surgery. Significance of the difference in its levels in patients with normal and ischemic parathyroid glands was evaluated. Results. In 26 patients, vascularization was considered sufficient, in 9 patients the glands were ischemic per the fluorescent examination. Statistically significant difference of ionized calcium levels were observed between groups with ischemic and normal glands at 18 hours after the surgery (mean 1.060 ± 0.53 in ischemic vs. 1.110 ± 0.56 in normal group, p &lt;0.05). Conclusion. Intraoperative IGFA of the parathyroid glands can successfully predict early postoperative hypocalcemia. Further studies for accessing correlation with permanent hypocalcemia are required.

Use of Intraoperative Fluorescent Indocyanine Green Angiography for Real-Time Vascular Evaluation of Pericranial Flaps.

Pericranial flaps (PCFs) have been widely used for skull base reconstruction. The key to successful skull base reconstruction using PCF depends on flap vascularity, but there have been no reports describing the real-time vascularity of PCF. In this study, we performed intraoperative fluorescent indocyanine green angiography to evaluate the real-time vascularity and viability of PCF and to estimate the reliability of this flap. Eleven anteriorly based PCF (with a bilateral pedicle, ipsilateral pedicle, and random-pattern flap) and 11 laterally based PCF (with and without temporal muscle) were included in this study. The flap vascularity of each flap type considering the patients' background was evaluated using indocyanine green angiography intraoperatively. Anteriorly based PCF had significantly better vascularity compared to laterally based PCF. In anteriorly based PCF, there was no significant difference in vascularity between PCF with bilateral pedicles and an ipsilateral pedicle. In laterally based PCF, PCF without temporal muscle showed a wider vascular area compared to PCF with temporal muscle. As for the patient background, those older than 45 years, body mass index more than 25, and who were smokers tended to have lower vascularity. Preoperative radiation therapy did not show any significant differences in terms of flap vascularity. Anteriorly based PCF had significantly better vascularity compared to laterally based PCF and seemed safer to harvest regardless of flap pedicle type. Also, the feasibility of harvesting muscle sparing laterally based PCF was indicated. Finally, being older than 45 years, a body mass index more than 25, or being a smoker might increase the risk of reducing flap vascularity.

Improving Outcomes for Lower Extremity Amputations: Can Intraoperative Fluorescent Angiography Predict Flap Viability?

Improving Outcomes for Lower Extremity Amputations: Can Intraoperative Fluorescent Angiography Predict Flap Viability?

Quantitative evaluation of blood perfusion to nerves included in the anterolateral thigh flap using indocyanine green fluorescence angiography: a different contrast pattern between the vastus lateralis motor nerve and femoral cutaneous nerve.

Better postoperative results can be expected in nerve reconstruction when vascularized nerve grafts are used. Previous studies reported reconstruction with flaps including "vascularized" nerves; however, few have evaluated blood supply to these nerves. The aim of this study was to quantitatively assess blood perfusion to nerves included in anterolateral thigh (ALT) flaps by indocyanine green (ICG) fluorescence angiography. Participants comprised eight patients who underwent reconstructive surgery with nerve defects using free ALT flaps, including the vastus lateralis motor nerve and/or femoral cutaneous nerve. Intraoperative ICG fluorescent angiography was performed. Time after the drug injection and the intensity of fluorescence in these nerves were analyzed as time-intensity curves. Maximum intensity (Imax), time to Imax (Tmax), and time at the beginning of intensity elevation (Te) were measured at three points: Point C, the central portion of the flap-attached region of the nerve; Point P, 2 cm from the proximal flap-attached edge; and Point D, 2 cm from the distal edge. Imax and Te at point C and Imax/Tmax-Te at point P were significantly different between these two nerves (p = 0.03125, p = 0.02895, p = 0.03125, respectively). Fluorescence in the vastus lateralis motor nerve was slightly quicker and stronger than that in the femoral cutaneous nerve, and also exhibited an axial pattern of fluorescence. Intraoperative ICG fluorescent angiography can be used to determine which nerve is better for nerve reconstruction. The indexes of Imax, Te, and Imax/Tmax-Te may be the suitable criteria for decision making regarding donor nerve selection.

Comparison of clinical and histological tumour diameter in non-melanoma skin malignancy of the Head and Neck

Purpose: Reconstruction of complex defects of the head and neck region utilizing micro-vascular free tissue transfer reconstruction has become invaluable. Early detection of vascular compromise and its prompt correction is critical to its success. The use of intra-operative fluorescent angiography (ICG) may facilitate surgeons in being objective when assessing micro-vascular anastamosis patency and flap perfusion. Method: 231 head and neck free tissue transfer cases on 228 patients performed by a single surgeon between 20032013 were reviewed for type of flap, flap success and complications. In 62 of the head and neck free tissue transfer cases, intra-operative ICG was performed with SPY Elite (Lifecell) for assessment of micro-vascular anastomosis patency and analysis of adequacy of blood supply to inset flap. Conventional subjective patency test and clinical inspection were performed for the remaining 169 cases. Results: Overall success rate was 95%. When ICG analysis was performed, the success rate was 97%. In the conventional group, the success rate was 94%. Overall complication rate was 11%. Post-operative complications included hematoma, venous thrombosis, infection, partial flap necrosis, and hemorrhage. In the ICG analysis cases, the overall complication rate was 5% with hematoma 3% and partial flap necrosis 2%. In the conventional subjective analysis group, the overall complication rate was 14% with post op complications of hematoma 7%, venous thrombosis 4%, infection 1%, partial flap necrosis 1% and hemorrhage 1%. Conclusions: Routine implementation of intraoperative ICG analysis can further increase the reliability of free tissue transfer reconstruction of the head and neck region.