Postoperative Flap Monitoring Research Articles

Development of an Automated Free Flap Monitoring System Based on Artificial Intelligence

Meticulous postoperative flap monitoring is essential for preventing flap failure and achieving optimal results in free flap operations, for which physical examination has remained the criterion standard. Despite the high reliability of physical examination, the requirement of excessive use of clinician time has been considered a main drawback. To develop an automated free flap monitoring system using artificial intelligence (AI), minimizing human involvement while maintaining efficiency. In this prognostic study, the designed system involves a smartphone camera installed in a location with optimal flap visibility to capture photographs at regular intervals. The automated program identifies the flap area, checks for notable abnormalities in its appearance, and notifies medical staff if abnormalities are detected. Implementation requires 2 AI-based models: a segmentation model for automatic flap recognition in photographs and a grading model for evaluating the perfusion status of the identified flap. To develop this system, flap photographs captured for monitoring were collected from patients who underwent free flap-based reconstruction from March 1, 2020, to August 31, 2023. After the 2 models were developed, they were integrated to construct the system, which was applied in a clinical setting in November 2023. Conducting the developed automated AI-based flap monitoring system. Accuracy of the developed models and feasibility of clinical application of the system. Photographs were obtained from 305 patients (median age, 62 years [range, 8-86 years]; 178 [58.4%] were male). Based on 2068 photographs, the FS-net program (a customized model) was developed for flap segmentation, demonstrating a mean (SD) Dice similarity coefficient of 0.970 (0.001) with 5-fold cross-validation. For the flap grading system, 11 112 photographs from the 305 patients were used, encompassing 10 115 photographs with normal features and 997 with abnormal features. Tested on 5506 photographs, the DenseNet121 model demonstrated the highest performance with an area under the receiver operating characteristic curve of 0.960 (95% CI, 0.951-0.969). The sensitivity for detecting venous insufficiency was 97.5% and for arterial insufficiency was 92.8%. When applied to 10 patients, the system successfully conducted 143 automated monitoring sessions without significant issues. The findings of this study suggest that a novel automated system may enable efficient flap monitoring with minimal use of clinician time. It may be anticipated to serve as an effective surveillance tool for postoperative free flap monitoring. Further studies are required to verify its reliability.

Ultrasound in Microsurgery: Current Applications and New Frontiers.

Ultrasound has revolutionized reconstructive microsurgery, offering real-time imaging and enhanced precision allowing for preoperative flap planning, recipient vessel identification and selection, postoperative flap monitoring, and lymphatic surgery. This narrative review of the literature provides an updated evidence-based overlook on the current applications and emerging frontiers of ultrasound in microsurgery, focusing on free tissue transfer and lymphatic surgery. Color duplex ultrasound (CDU) plays a pivotal role in preoperative flap planning and design, providing real-time imaging that enables detailed perforator mapping, perforator suitability assessment, blood flow velocity measurement, and, ultimately, flap design optimization. Ultrasound also aids in recipient vessel selection by providing assessment of caliber, patency, location, and flow velocity of recipient vessels. Postoperatively, ultrasound enables real-time monitoring of flap perfusion, providing early detection of potential flap compromise and improved flap survival rates. In lymphatic surgery, ultra-high frequency ultrasound (UHFUS) offers precise mapping and evaluation of lymphatic vessels, improving efficacy and efficiency by targeting larger dilated vessels. Integrating ultrasound into reconstructive microsurgery represents a significant advancement in the utilization of imaging in the field. With growing accessibility of devices, improved training, and technological advancements, using ultrasound as a key imaging tool offers substantial potential for the evolution of reconstructive microsurgery.

Tissue perfusion in DIEP flaps using Indocyanine Green Fluorescence Angiography, Hyperspectral imaging, and Thermal imaging

Flap necrosis continues to occur in skin free flap autologous breast reconstruction. Therefore, we investigated the benefits of indocyanine green angiography (ICGA) using quantitative parameters for the objective, perioperative evaluation of flap perfusion. In addition, we investigated the feasibility of hyperspectral (HSI) and thermal imaging (TI) for postoperative flap monitoring. A single-center, prospective observational study was performed on 15 patients who underwent deep inferior epigastric perforator (DIEP) flap breast reconstruction (n=21). DIEP-flap perfusion was evaluated using ICGA, HSI, and TI using a standardized imaging protocol. The ICGA perfusion curves and derived parameters, HSI extracted oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) values, and flap temperatures from TI were analyzed and correlated to the clinical outcomes. Post-hoc quantitative analysis of intraoperatively collected data of ICGA application accurately distinguished between adequately and insufficiently perfused DIEP flaps. ICG perfusion curves identified the lack of arterial inflow (n=2) and occlusion of the venous outflow (n=1). In addition, a postoperatively detected partial flap epidermolysis could have been predicted based on intraoperative quantitative ICGA data. During postoperative monitoring, HSI was used to identify impaired perfusion areas within the DIEP flap based on deoxyHb levels. The results of this study showed a limited added value of TI. Quantitative, post-hoc analysis of ICGA data produced objective and reproducible parameters that enabled the intraoperative detection of arterial and venous congested DIEP flaps. HSI appeared to be a promising technique for postoperative flap perfusion assessment. A diagnostic accuracy study is needed to investigate ICGA and HSI parameters in real-time and demonstrate their clinical benefit.

Mandibular reconstruction using an iliac bone flap with perforator-supported external oblique abdominal muscle island: a pilot study

The deep circumflex iliac artery (DCIA) flap is one of the bone flaps commonly used for mandibular reconstruction. Observation of the skin paddle and Doppler ultrasound are methods that are usually used to monitor DCIA flaps after mandibular reconstruction surgery. The aim of this study was to introduce a novel DCIA flap with a perforator-supported external oblique abdominal muscle (EOAM) island for postoperative flap monitoring. This study included five patients who underwent mandibular reconstruction using this modified technique. The DCIA flap and the EOAM island supplied by the ascending branch of the DCIA were harvested during the surgery. After mandibular reconstruction, the EOAM island was placed in the submandibular region to monitor the blood supply to the DCIA flap after surgery. The blood supply to the DCIA flap was monitored by observing the colour, texture, and bleeding condition of the EOAM island. After the monitoring period, the EOAM was removed and the ascending branch of the DCIA was ligated. The outcome was successful in all patients. The EOAM island supported by the ascending branch of the DCIA is reliable and safe, thus providing a robust option to monitor the blood supply to the DCIA flap.

NIR-II Protein-Escaping Dyes Enable High-Contrast and Long-Term Prognosis Evaluation of Flap Transplantation.

Real-time vascular positioning, postoperative flap monitoring, and vascular reconstruction assessment are of great importance in flap transplantation. Cyanine dyes offer the advantage of high resolution in the Near-infrared-II (NIR-II)imaging window. However, the nonspecific binding of many cyanine dyes to endogenous albumin leads to high organ accumulation and skin absorption, resulting in low-quality imaging and poor reproducibility of contrast during long-term (e.g., 7 days) postoperative monitoring. Here, a novel strategy is proposed that can be widely applied to prevent protein binding for NIR-I/IICl-containing cyanine dyes. This strategy produces protein-escaping dyes, ensuring high fluorescence enhancement in the blood with rapid clearance and no residual fluorescence, allowing for short-term repeatable injections for vascular imaging. This strategy in the perioperative monitoring of pedicle perforator flap models in mice and rats is successfully applied. Furthermore, leveraging the universality of this strategy, multiple nonoverlapping protein-escaping probes that achieve dual-excitation (808 and 1064nm) interference-free imaging of nerve-vessel and tumor-vessel simultaneously are designed and synthesized. These protein-escaping dyes enable long-term repeatable dual-color imaging of tumor localization, resection, and tumor-vessel reconstruction at the wound site.

Role of Lactate Measurement in Flap Monitoring: An Useful Adjunct.

Background Detection of vascular compromise in flap is often a challenging task for reconstructive surgeons. A timely salvage procedure depends on objectivity and reliability of postoperative flap monitoring. This study determined if flap capillary lactate helps in prediction of flap viability in first 48 postoperative hours of surgery. Methods We conducted this study on all flaps with accessible skin paddle where capillary lactate values were assessed along with clinical observation to check viability of flap at 0, 1, 6, 12, 24 and 48 hours of surgery. The data was statistically analyzed for significance and area under the receiver operating characteristic curve was used for calculating cutoff value for lactate. Results Out of a total of 30 patients included in this study, 25 were males and the mean age was 45.03 years. Fifteen patients underwent free flap and rest pedicled. Highly significant association of role of clinical observation in the outcome of flap was found. The average of lactate values for survived and distally ischemic flap was 5.32 ± 1.91 and 8.38 ± 1.81, respectively, which was highly significant. The cutoff value of lactate below which all flaps survived was found to be 6.09 mmol/L. Conclusion Flap capillary lactate measurement is an easy, quick, cost-effective, and objective tool for checking viability of flaps.

A Wireless Infrared Thermometry Device for Postoperative Flap Monitoring: Proof of Concept in Patients.

Postoperative flap perfusion assessment methods still rely on the evaluation of traditional clinical indicators, which have the disadvantage of being subjective and burdensome. This study describes a self-designed infrared wireless thermometer for flap blood supply monitoring and evaluates its efficacy in the postoperative monitoring of 40 free flaps. The device consists of multiple temperature and humidity modules as well as a wireless module, which has the advantages of low cost and continuous remote monitoring. The alarm time of the wireless infrared thermometer was 30.5 ± 3.1hours, and the clinical observation reported 41.7 ± 13.6hours. In future studies, the device will be tested on different types of flaps in a porcine model.

Detecting flap compromise: an updated review of techniques to monitor microsurgical flaps post-operatively in breast reconstruction

Breast reconstructive surgery utilizing free tissue transfer has revolutionized the restoration of aesthetic and functional outcomes for patients. Even for the most routine free flap procedures, substantial hospital resources and costs are necessary. The effectiveness of free flap surgery, along with any reconstructive procedure, hinges upon meticulous patient selection, thorough pre-operative planning, well-informed peri-operative decision-making, and diligent post-operative monitoring and care for the patient. This article presents a review of standard clinical care monitoring techniques during the post-operative period, as well as the diverse strategies currently employed for post-operative flap monitoring.

A wireless infrared thermometry device for postoperative flap monitoring: Proof of concept in a porcine flap model.

The application of flap surgery is becoming more and more widespread with the development of microsurgical techniques. Currently, postoperative blood flow monitoring of flaps is still mainly assessed by medical staff for traditional clinical parameters, which has the disadvantage of being subjective and unable to monitor in real-time. This study describes a self-contained infrared wireless infrared thermometry device for flap blood supply monitoring and evaluates its effectiveness on eight porcine flap models. A scapular muscle flap model was established using eight small pigs, and the vessels were ligated at irregular intervals using a lumir ligature to simulate arterial crisis and venous crisis. Laser Doppler flowmetry (LDF), the wireless infrared thermometry device, and traditional clinical observation methods were applied to monitor the blood supply of the flap and evaluate the effect. The time to the determination of blood supply disturbance by wireless infrared thermography (IRT) was 28.75 ± 3.30 min and 96.5 ± 27.09 min for the arterial and venous groups, respectively; by LDF was 6.00 ± 1.41 min and 52.75 ± 15.76 min; by clinical observation was 42.00 ± 8.60min and 156.50 ± 40.91min, respectively. Paired t-tests were performed between the wireless IRT device and clinical observations, and the statistical results were significantly different in the arterial group and not significantly different in the venous group. Paired t-testing of the wireless infrared thermometry device with the LDF also showed significant differences in the arterial group and non-significant differences in the venous group. This wireless infrared thermometry device outperforms traditional clinical observation methods in monitoring blood supply in a porcine skin flap model. Because of its low cost, real-time monitoring, simple operation, and non-invasive features, it has the potential to be used in clinical practice as a routine means of postoperative blood supply monitoring in flap surgery.

Diagnostic Accuracy of Microdialysis in Postoperative Flap Monitoring.

Postoperative monitoring plays an important role in achieving success in microvascular free tissue transfer. A systematic review was designed to evaluate the clinical outcomes of microdialysis in flap monitoring and a meta-analysis was conducted for diagnostic accuracies. The search terms "microdialysis" and "flap" were used in a PubMed and Scopus search, resulting in 60 and 78 results, respectively. Among 78 titles, 15 articles were excluded. Among 63 abstracts, 43 abstracts were excluded. From 20 full texts, 7 articles were excluded because they did not have sufficient content (ie, the statistical values in question). A systematic review was conducted of the final 13 articles. The overall sensitivity was 97.24% [95% confidence interval (CI)=93.67%-99.10%]. Eleven of the 13 studies showed 100% sensitivity and 2 studies had 2 and 3 false negative results, resulting in sensitivity values of 85.8% and 95.3%. Specificity ranged from 91.89% to 100%, and the overall value was 98.15% (95% CI=96.80%-99.04%). The positive predictive value ranged from 84.62% to 100%, with an overall value of 93.62% (95% CI=89.33%-96.26%). The negative predictive value ranged from 94.44% to 100%, with an overall value of 99.22% (95% CI=98.17%-99.67%). The overall flap success rate (survival rate) was 93.7% (786/839). The lowest flap survival rate was 86.7% and the highest was 100%. Microdialysis provides excellent diagnostic accuracy and enables the early detection of ischemia in postoperative flap monitoring. Although microdialysis is not the most popular choice among surgeons, it should be considered adjacent to conventional clinical monitoring. Cost-effectiveness, availability, and ease of application remain hurdles.

Autologous free tissue transfer in paediatric patient with a univentricular heart.

We report on the case of a 30-month-old boy who developed severe deep cervical necrosis after bypass surgery for total cavopulmonary connection, followed by low-cardiac output and extracorporeal life support. As several bedside debridements failed to result in sufficient wound healing, a 2-stage necrectomy followed by autologous reconstruction with a free anterolateral thigh-flap was required. Due to impaired circulation, postoperative flap monitoring was extremely difficult. To ensure flap perfusion, mean arterial pressure had to be raised by catecholamines over 7 days.

Comparing tissue oximetry to doppler monitoring in 1367 consecutive breast free flaps.

Retrospective studies evaluating tissue oximetry in a more recent cohort have shown superiority in flap outcomes. This study compares the use of tissue oximetry in a historical cohort to clinical observation and handheld doppler in a more recent cohort. We hypothesize that there is no benefit to using tissue oximetry. A retrospective review was performed on patients who underwent abdominal-based autologous breast reconstruction by five microsurgeons at an academic institution from 2009 to 2020. Method of postoperative flap monitoring was determined then operative details and complications were analyzed. 1367 flaps were reviewed; 740 flaps in 460 patients were monitored with clinical observation and tissue oximetry, and 627 flaps in 391 patients were monitored with clinical observation and handheld doppler. There were no statistical differences in ischemic (p= .59) or congestive complications (p= .41), flap salvage rates when exploring for venous or arterial compromise (p= .52), or early flap loss (p= .56). Although not significant, acute flap-related return to the operating room was lower in the doppler group (4.6%) compared to the oximetry group (6.1%; p= .22). Flaps monitored with tissue oximetry had a statistical increase in length of stay (4.8 ± 1.4 days vs. 3.8 ± 1.6 days; p ≤ .001). The rates of late partial flap loss and fat necrosis were significantly higher in the oximetry group (2.6%, 19/740 vs. 0.3%, 2/740; p= .04) and (18.2%, 135/740 vs. 13.6%, 85/627; p= .02), respectively. There is no statistical benefit to the use of tissue oximetry compared to handheld doppler in flap monitoring with regards to flap outcomes.

New Approach to the Old Challenge of Free Flap Monitoring-Hyperspectral Imaging Outperforms Clinical Assessment by Earlier Detection of Perfusion Failure.

In reconstructive surgery, free flap failure, especially in complex osteocutaneous reconstructions, represents a significant clinical burden. Therefore, the aim of the presented study was to assess hyperspectral imaging (HSI) for monitoring of free flaps compared to clinical monitoring. In a prospective, non-randomized clinical study, patients with free flap reconstruction of the oro-maxillofacial-complex were included. Monitoring was assessed clinically and by using hyperspectral imaging (TIVITA™ Tissue-System, DiaspectiveVision GmbH, Pepelow, Germany) to determine tissue-oxygen-saturation [StO2], near-infrared-perfusion-index [NPI], distribution of haemoglobin [THI] and water [TWI], and variance to an adjacent reference area (Δreference). A total of 54 primary and 11 secondary reconstructions were performed including fasciocutaneous and osteocutaneous flaps. Re-exploration was performed in 19 cases. A total of seven complete flap failures occurred, resulting in a 63% salvage rate. Mean time from flap inset to decision making for re-exploration based on clinical assessment was 23.1 ± 21.9 vs. 18.2 ± 19.4 h by the appearance of hyperspectral criteria indicating impaired perfusion (StO2 ≤ 32% OR StO2Δreference > −38% OR NPI ≤ 32.9 OR NPIΔreference ≥ −13.4%) resulting in a difference of 4.8 ± 5 h (p < 0.001). HSI seems able to detect perfusion compromise significantly earlier than clinical monitoring. These findings provide an interpretation aid for clinicians to simplify postoperative flap monitoring.

Postoperative Detection of Free Flap Congestion in a Fitzpatrick Skin Type VI Patient using the Flir Thermal Imaging Camera: A Case Report and Literature Review

BACKGROUND: Free flaps are routinely used in complex tissue reconstruction due to their functionality and reliability. Postoperative monitoring remains a challenge despite the current available modalities. Clinical examination remains the gold standard, with color being the most sensitive marker of flap compromise. Assessment of flap color is more challenging in Fitzpatrick V-VI skin types, masking visual signs of ischemia or congestion. A Forward-Looking Infrared (FLIR) ONE smartphone based thermal imaging camera can be used to detect differences in flap temperature from the surrounding native tissue and could be used to identify early flap compromise. This simple technology used with a smartphone may be a useful method to assess postoperative flap perfusion. METHODS: Institutional review board approval was obtained for postoperative flap monitoring using FLIR technology for patients undergoing complex reconstruction with a free anterolateral thigh (ALT) flap. The FLIR camera is a simple attachment that plugs into iPhone models 7–12 and takes thermal pictures with temperature readings by a spot pyrometer using their App. Preoperatively the FLIR camera spot pyrometer measured baseline temperature by ALT flap location. Temperature recordings of the flap and the surrounding native tissue were taken immediately postoperatively and then at regular intervals in addition to our standard free flap monitoring protocol. This protocol was utilized for one patient in this report who underwent a free ALT flap to scalp after sarcoma resection and Fitzpatrick skin type VI. RESULTS: FLIR thermography measured the preoperative central flap temperature at 32.6°C. Immediately postoperatively the flap temperature was 33.9°C, and the surrounding native skin was 35.8°C. Sixteen hours postoperatively the central portion of the flap was found to be 28.0°C, 8.4°C cooler than the surrounding native skin, suggesting flap ischemia. Clinical examination of the flap showed edema and return of dark blood on scratch test but no frank discoloration. Handheld Doppler signal showed arterial signal but no venous signal. The patient was taken immediately for operative exploration, which showed a 30 cm3 hematoma compressing the vascular pedicle. Following evacuation, the central flap’s temperature was 35.6°C. The patient was discharged on POD 7 and still has a complete reconstruction. CONCLUSIONS: FLIR ONE was helpful in detecting flap congestion and ultimately flap salvage. Prompt operative evacuation of the hematoma prevented flap loss and associated morbidity to the patient. This patient case highlights the inherent challenges in evaluating skin paddles of Fitzpatrick V–VI skin types and depicts the utility of a low-cost thermography camera that can aid in identifying a threatened flap. The user-friendly, non-contact nature of FLIR ONE adds a useful and objective datapoint in postoperative free flap monitoring that can improve patient outcomes when combined with conventional monitoring techniques in all patients, particularly those with difficult flaps to monitor. Our team hopes to continue studying thermal camera temperature differences in postoperative free flap monitoring to service our patients and provide insight into this technology’s utility for reconstructive plastic surgery.

507 Quantifying the Limitations of Clinical and Technology-Based Flap Monitoring Strategies Using A Systematic Recurrent Themes Analysis

Abstract Aim Multiple techniques exist to monitor free flap viability postoperatively, varying with practical and personal preference, yet the limitations of each technique remain unquantified. This systematic review aims to identify the most commonly reported limitations of these techniques in clinical practice. Method A systematic review was conducted according to PRISMA guidelines using MEDLINE, EMBASE and Web of Science with search criteria for postoperative free flap monitoring techniques. Search results were independently screened using defined criteria by two authors and a senior clinician. Limitations of the techniques found in the discussion section of eligible papers were recorded and categorised using recurrent theme analysis. Results A total of 4826 records were identified. 4643 articles met the eligibility criteria and were subsequently reviewed, with 195 papers included in the final analysis. The most frequently reported limitations of clinical monitoring were interpretation requiring expertise (25% of related papers), unsuitability for buried flaps (21%), and lack of quantitative/objective values (19%). For non-invasive technologies: lack of quantitative/objective values (21%), cost (16%) and interpretation requiring expertise (13%). For invasive technologies: application requiring expertise (25%), equipment design and malfunction (13%) and cost (13%). Conclusions This is the first systematic review to quantify the limitations of different flap monitoring techniques as reported in the literature. The limitations identified better inform clinicians to decide the best single or combined monitoring approach for their practice and aid development in new flap monitoring technologies.

Developing a Wearable Sensor for Continuous Tissue Oxygenation Monitoring: A Proof of Concept Study

Abstract Objective Technologies facilitating continuous free tissue flap monitoring such as near infrared spectroscopy (NIRS) have been shown to improve flap salvage rates. However, the size and associated costs of such technology create a barrier to wider implementation. The aim of this study was to develop and validate a wearable sensor for continuous tissue oxygenation monitoring. Materials and Methods A forearm ischemia model was designed by using a brachial pressure cuff inflation protocol. Twenty healthy subjects were recruited. The forearm tissue oxygenation of each subject was monitored throughout the pressure cuff protocol by using a new optical sensor (Imperial College London), and a gold standard tissue spectrometry system (O2C, Medizintecknik, LEA, Germany). Data were processed to allow quantitative deoxygenation episode comparisons between inflations and sensor modalities. Results The correlation between O2C and optical sensor oxygenation measurements was moderate (average R = 0.672, p &lt; 0.001). Incremental increases in cuff inflation duration resulted in a linear increase in deoxygenation values with both O2C and optical sensors, with significant differences recorded on consecutive inflations (wall shear rate, p &lt; 0.005). The presence or absence of pulsatile blood flow was correctly determined throughout by both sensor modalities. Conclusion This study demonstrates the ability of a small optical sensor to detect and quantify tissue oxygenation changes and assess the presence of pulsatile blood flow. Low power, miniaturized electronics make the device capable of deployment in a wearable form which may break down the barriers for implementation in postoperative flap monitoring.

Outpatient Microsurgical Breast Reconstruction.

Background:The extensive nature of perforator-based breast reconstructions, combined with the need for postoperative flap monitoring, often leads to long hospitalizations. We present an early report demonstrating the feasibility and advantages of a modified operative technique and recovery protocol, allowing us to perform outpatient breast reconstructions with the DIEP flap. This follow-up comprises the experience gained, which is expanded to other perforator-based flaps and not limited to DIEP breast reconstructions.Methods:We have implemented a general protocol in patients undergoing breast reconstruction with autologous flaps, promoting early mobilization and discharge by improving postoperative pain and decreasing opioid requirements. This protocol includes intraoperative local anesthesia, a microfascial incision for DIEP harvest with rib preservation, along with prophylactic anticoagulation.Results:Ninety-two consecutive patients underwent autologous tissue-based breast reconstruction with DIEP, IGAP, and PAP flaps. No intraoperative complications were reported. All patients were discharged within 23 hours, without evidence of flap compromise. One patient required operative takeback for evacuation of a hematoma on postoperative day 4. No partial or total flap losses were documented. The aim of any procedure should be to get to the patient back to the preoperative status as quickly as possible, as prolonged hospitalizations are associated with higher incidences of infection, deep venous thrombosis, overall dissatisfaction, and higher overall costs of care.Conclusions:By using a modified operative technique, multimodal pain control, and postoperative anticoagulant therapy, outpatient perforator-flap–based breast reconstructions can be performed with high success and low complication rates.

Hyperspectral imaging for postoperative flap monitoring of pedicled flaps

Since pedicle flaps were first described by the Indian physician Sushruta Samhita in the 6th century B. C., they have become an integral part of reconstructive surgery. As more and more research has been conducted into the underlying physical principles, flap monitoring has developed steadily in the last few decades. Hyperspectral Imaging (HSI) is a new quantitative measuring method for assessing the perfusion of the underlying tissue. This study aims to evaluate HSI as a monitoring method for pedicle flaps. In 16 patients who had undergone reconstructive surgery, oxygen saturation, haemoglobin and water concentration of the locoregional flap, necrotic flap areas as well as intact skin were measured on postoperative days 1 to 7. Subsequently, the data were statistically described and graphically illustrated. HSI revealed increased haemoglobin concentration and decreased oxygen and water concentration in necrotic flap areas compared with the monitor island and healthy skin. The distribution of the values collected from the vital skin areas and the monitor island was almost identical. HSI allows for safe, immediate, non-contact measurement of tissue perfusion of transferred tissue areas in patients after pedicle flap surgery. The use of HSI may improve postoperative flap monitoring.

The Value of Dynamic Infrared Thermography in Pedicled Thoracodorsal Artery Perforator Flap Surgery.

Background:Dynamic infrared thermography (DIRT) is a noninvasive imaging technique that can provide indirect and real-time information on skin perfusion by measuring skin temperature. Although used in flap surgery, there are no reports on its value in procedures using a pedicled thoracodorsal artery perforator (TDAP) flap. The aim of this study was to assess the usefulness of DIRT in preoperative perforator mapping and in monitoring intra- and postoperative flap perfusion of pedicled TDAP flaps.Methods:This prospective study comprised 21 patients (21 flaps) scheduled for reconstructive surgery with a TDAP flap. Perforator mapping was done by DIRT, handheld unidirectional Doppler ultrasound, and computer tomography angiography. Intra- and postoperative flap perfusion was assessed by clinical signs and with the use of DIRT and handheld unidirectional Doppler ultrasound.Results:Perforator mapping with DIRT showed that first-appearing bright hotspots were always associated with arterial Doppler sounds and suitable perforators intraoperatively. Computer tomography angiography presented useful information on the thoracodorsal artery branching pattern but was less beneficial for perforator mapping. Intra- and postoperative flap monitoring with DIRT was more useful than handheld unidirectional Doppler ultrasound and clinical signs to detect early arterial and venous perfusion problems. DIRT demonstrated that TDAP flap perfusion is a dynamic process with an increase in perfusion during the first operative days. Nineteen flaps survived, of which 3 sustained distal necrosis. Two flaps were lost due to inadequate blood perfusion.Conclusion:DIRT provides valuable real-time information for perforator mapping and for monitoring TDAP flap perfusion intra- and postoperatively.

Telemedicine in Transgender Care: A Twenty-First-Century Beckoning.

The advent of telemedicine has undoubtedly revolutionized the practice of health care. With advances in photograph and live relay quality, and the ease of data transmission through the Internet, telemedicine has great potential in the field of plastic surgery. The majority of consultations in plastic surgery require visual diagnoses, thereby enabling telemedicine to help tackle issues of health care costs and accessibility.1,2 Telemedicine can help decrease patient travel and health care costs. Costa et al. described an average of 239 miles of travel avoided per visit for patients residing in the United States by using video teleconferencing for cleft lip/palate evaluations.3 At the same time, telemedicine-based approaches have been cited for having a high degree of accuracy.2,4 Engel et al. identified similar diagnostic accuracy between in-person examinations for free flap monitoring compared with remote smartphone photographic assessments.4 However, there is a paucity of literature focusing on the utility of telemedicine in the care of the transgender population. Despite the increasing social acceptance, gender-diverse people still face major challenges in access to appropriate health care.5–7 Thus, there is an urgent necessity to improve health care access for the transgender population.6,7 In 2017, Herman et al. found that approximately 1.4 million adults (0.6 percent of adults in the United States) and 150,000 youths (0.7 percent of the youths aged 13 to 17 in the United States) identify as transgender.8 Individuals who identify as transgender and seek medical or surgical transition require interdisciplinary health care involving multiple medical and ancillary services.6 Plastic surgeons play an invaluable role in gender-affirming operations in patients desiring these options.7,9 However, because of their complexity, these procedures are often limited to tertiary centers with specialized teams, which limits access to a large percentage of the transgender population.10 Many clinical assessments are amenable to telehealth, which can greatly facilitate health care access, decrease travel time, and reduce costs and wait times for these patients. Following gender-affirming surgery, there is a need for postoperative flap monitoring and assessment of wound healing.7,9 Scheduled postoperative telemedicine consultations would permit early identification of symptoms suggestive of complications. Furthermore, psychosocial issues continue after surgery and require periodic evaluation and support, which could be addressed through telehealth intervention. Recent literature has discussed the successful pilot implementation of telemedicine for providing transgender care in the Veteran’s Health Administration.6,11 These pilot studies reiterate the prospect of telemedicine in transgender care. However, the outcomes of telemedicine in the field of reconstructive surgery in this population are still lacking. In summary, both telemedicine and transgender care have been evolving over the past decade, particularly because of growing recognition and social awareness.7,12 Although telemedicine has been extensively adopted in plastic surgery2 and is starting to make steady inroads into transgender care,11 the cluster of these three fields has immense potential for revolutionizing the treatment of this population. Future studies should explore the effectiveness of telemedicine for improving outcomes and optimizing access to health care for this underserved population. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article.