A picture speaks a thousand words: the use of digital photography and the Internet as a cost-effective tool in monitoring free flaps

Microsurgical free tissue transfer is progressing rapidly and is being used more frequently the world over. Monitoring these cases is crucial for a satisfactory outcome. More sophisticated methods are available for monitoring, though they are often expensive. We propose a novel technique using digital photography and the Internet to offer a reliable and cost-effective method to monitor free-tissue transfers. During an 8-month period, 163 microvascular procedures were monitored using this technique. Serial photographs taken were stored in a separate case folder and sent to the surgeon as deemed necessary.Analysis of the 67 cases is presented. Five reexplorations were done. The early diagnosis of venous congestion was possible using this technique. Timely intervention contributed to the success of the reexplorations, and these flaps could be salvaged. The file size of images was in the range of 1 MB to 6 MB. The file size of a set of photographs was usually around 7 MB to 9 MB. These were sent across the asymmetric digital subscriber line Internet lines.The use of the digital images and the Internet allows reconstructive surgeons to have a reliable picture of the state of their free-tissue transfers. This allows decreasing observer error and saves valuable time which otherwise needs to be spent to verify situations of doubt.     

The effect of learning curve on flap selection,re‐exploration,and salvage rates in free flaps; A retrospective analysis of 155 cases

The purpose of this study is to report our experience and learning curve in avoiding complications at both the recipient and donor sites as well in choosing the best flap for different anatomic locations. For this purpose 155 free flaps done between October 2005 and August 2012 were retrospectively examined. Patient demographics, flap types, etiology, re‐exploration indications, timing of the re‐explorations, and salvage rates were documented. In the first 60 cases, our re‐exploration rate was 26.7% (16 flaps), and the rate decreased to 15.0% for the second 60 flaps (9 flaps). In correlation with this decrease, in the last 35 cases, only three flaps were re‐explored (8.6%). This decrease in re‐exploration rates over time was statistically significant (P = 0.021). Re‐exploration rates for axial and perforator flaps were 14.6% and 22.7%, respectively. Salvage rates were 76.9% in axial flaps and 53.3% in perforator flaps. The total success rate for axial flaps was 95.5% and for perforator flaps was 89.4%. Besides, re‐exploration rates were higher with lower salvage rates in perforator flaps compared to axial flaps causing lower overall success rates in the former group. The mean time of re‐explorations was 21.4 hours. Salvage rates were significantly higher in re‐explorations done within the first 12 hours after the initial surgery than in re‐explorations done after 12 hours (83.3% vs. 47.3%) (P = 0.040). We can conclude that axial flaps have a steeper learning curve and are safer options for the inexperienced reconstructive micro‐surgeons until they have adequate experience with the perforator dissection. © 2013 Wiley Periodicals, Inc. Microsurgery 33:519–526, 2013.     

Factors influencing survival of free‐flap in reconstruction for cancer of the head and neck: A literature review

Microvascular free tissue transfer is a reliable technique for head and neck reconstruction with success rates of 90–99%. Currently, there is no consensus concerning antithrombotic agents, antibiotics, or monitoring techniques. Therefore, the aim of this study was to review current literature dealing with microvascular free‐tissue transfer and factors influencing the outcome. In addition to excellent microsurgical techniques, coupling devices are a promising new technique, but are not useful in all arteries. Antibiotics should be given in three doses, as a more lengthy dosage time seems to have no advantage. The risk for elderly patients can be best assessed by the American Society of Anesthesiologists (ASA) score, but early mobilization, including intense chest physiotherapy, is important. Anticoagulation can be considered in cases of small vessels, significant size mismatch, vein graft, or vessels of poor quality. Monitoring should be done hourly during the first 24 hours and then every 4 hours for the next 2 postoperative days. © 2010 Wiley‐Liss, Inc. Microsurgery, 2010.     

Use of telepathology to provide rapid diagnosis of neurosurgical specimens

To determine whether still digital images of neurosurgical specimens sent by e-mail are an effective and safe way of obtaining an emergency pathological diagnosis, representative images from 48 neurosurgical smear specimens were digitized, compressed and sent by electronic mail to our consultant neuropathologist with relevant clinical and radiological information. The time to select, digitize, compress and send the images for each case was recorded. Comparison was made between diagnosis made from digital images (DI) and historical smear (HS) using the original permanent section (PS) diagnosis as the gold standard. A diagnosis of normal vs. abnormal, neoplastic vs. non-neoplastic, primary vs. secondary and tumor grade was made in each case. The mean time for selection and digitalization of each case was 9.51 minutes. The number of correct pathological diagnosis was 41/48 using DI and 48/48 using HS, giving an accuracy rate of 85.4% and 100% respectively. DI was 100% sensitive in recognizing neoplastic tissue but only 98% specific. Most inaccuracies were in grading and caused by problems with field selection and familiarity with the technique. We conclude that static digital images are reliable and safe method of interpreting tissue during neurosurgical procedures. This corresponds with the findings of previous studies.     

Three‐dimensional multislice spiral computed tomographic angiography: A potentially useful tool for safer free tissue transfer to complicated regions

Three‐dimensional multislice spiral computed tomographic angiography (3D‐MSCTA) is a minimally invasive method of vascular mapping. The aim of this study was to evaluate the clinical usefulness of this imaging technique in delineating the recipient vessels for safer free tissue transfer to complicated regions. 3D‐MSCTA was performed preoperatively in 26 patients scheduled for free tissue transfer, in whom the availability of the recipient vessels were considered to be uncertain, and 23 of these were operated on. Radiographic and operative findings regarding the availability of the recipient vessels for anastomosis were correlated in 21 of these 23 patients. 3D‐MSCTA yielded two false‐positive results; anastomosis was not possible because of widespread atherosclerotic plaques and poor flow observed in the recipient arteries despite the good caliber observed in 3D‐MSCTA images. 3D‐MSCTA provides a noninvasive means of preoperatively assessing recipient site vessels for anatomic variations and suitability before free tissue transfer and enables the surgeon to establish an appropriate treatment plan. But it is not 100% reliable yet and the possibility of false‐positive results should be kept in mind, especially inthe patients with peripheral vascular disease. 3D‐MSCTA has the potential to replace digital subtraction angiography for planning of microvascular reconstructions and newer devices with higher resolutions will probably increase the reliability of this technique. © 2009 Wiley‐Liss, Inc. Microsurgery, 2009.     

192例头颈部游离组织瓣移植的临床分析

目的 对192例的204块头颈吻合血管的游离组织移植作回顾性分析。方法 1999年5月-2001年3月由同一术者完成手术192例，分析其一般情况、临床病理诊断、缺损情况、所采用组织瓣的类型、组织瓣成活情况及术后并发症的发生情况，并分析有可能影响皮瓣成活的各种因素。结果 前臂皮瓣（83块）、腓骨瓣（81块）和腹直肌肌皮瓣（32块）为采用最多的3种游离组织瓣，占全部组织瓣的96.1%；成功率为98.5%，术后11例发生血栓，其中8例经抢救成活，3例失败；57例受区和供区出现并发症，但大我数并发症均较轻，没有造成严重的后果；吸烟、饮酒、放疗和年龄（高龄和儿童）等均非影响组织瓣移植成功的重要因素。结论 头颈部游离组织瓣移植修复安全可靠，明显优于传统的带蒂组织瓣，值得进一步推广和应用。     

Techniques of postoperative blood flow monitoring after free tissue transfer: An overview

Ever since free tissue transfer has been established in microsurgery, success rates have greatly improved over the years, partly due to improved technical performance of microvascular anastomoses with better optical and instrumental aids. However, flap failure still occurs in 5–10%, mainly due to blood vessel thrombosis within the first 24 postoperative hours. Salvation rates of failing free tissue transfers can be optimized by in-time diagnosis of irreversibly compromised tissue blood flow and immediate operative reexploration. Therefore, there is a special demand for adequate and reliable postoperative monitoring techniques. This article gives an overview of all monitoring techniques, which have been performed both in the experimental and clinical setting thus far. © 1994 Wiley-Liss, Inc.     

Utility of “open‐Y” anastomosis technique in the use of superior thyroid artery as recipient vessel for head and neck reconstruction with free flap

Background: The superior thyroid artery (STA) is the most commonly used recipient vessel in free tissue transfer for head and neck reconstruction. Size discrepancy between recipient and donor vessels might affect the patency rate. The objective of this study was to compare the outcomes of the “open‐Y” technique in end‐to‐end anastomoses between the STA and donor arteries to those of conventional anastomoses to the STA. Patients and methods: A total of 337 patients with free tissue transfer for head and neck reconstruction with the STA as the recipient artery were recruited between September 2011 and August 2013. The “open‐Y” technique of anastomosis was used in 72 cases, whereas the conventional technique was applied in 256 cases. The arterial anastomotic site‐related complications and size discrepancy rates of both groups were evaluated and compared. Results: The flap success rate was 98.6% (71/72) in the “open‐Y” group, which was similar to the conventional group [97.4% (245/252); P = 0.999]. Size discrepancy rate was higher in the “open‐Y” group [48/72(66.7%)] compared to that in the conventional group [31/265(11.7%), P < 0.001]. There was no significant difference regarding arterial anastomotic site‐related complications between the “open‐Y” and conventional groups (1.4% vs.4.2%; P = 0.473). Others complications, including re‐exploration, venous thrombosis, hematoma, fistula, infection, partial flap necrosis and total flap necrosis, had similar presentations. Conclusion: The utility of the “open‐Y” technique, applied to STA as a recipient vessel, appeared to be a reasonable option for head and neck reconstruction. This technique seems to be promising for cases with vessels size discrepancy. © 2015 Wiley Periodicals, Inc. Microsurgery 36:391–396, 2016.     

Safety and reliability of microsurgical free tissue transfers in paediatric head and neck reconstruction--a report of 72 cases.

Although many large series of free tissue transfers for head and neck reconstruction have been reported in adults, there are few studies in paediatric patients. Seventy-three free tissue transfers for reconstruction of various defects of the head and neck were performed in 72 paediatric patients between January 1990 and September 2002, at our centre. The average age at the time of reconstruction was 11.8 years (range: 2 to 17 years). Thirty-eight patients were girls and 34 were boys. There were 19 tumour resection defects, 18 congenital oro-nasal fistula defects (cleft palate), 11 posttraumatic defects, nine corrosive pharyngo-oesophageal injuries, eight burn contractures, six hemifacial atrophies and microsomia, and one facial paralysis. Thirty-nine fasciocutaneous flaps, 16 osteoseptocutaneous flaps, 10 muscle or myocutaneous flaps, and eight jejunal flaps were transferred. The mean operative time was 8 h 20 min. All flaps survived, except one partial necrosis, with 98.6% success rate. Five patients (6.8%) required re-exploration. There were two venous and three arterial thromboses. All five flaps were successfully salvaged. The average hospital stay was 18 days. This study confirmed free tissue transfer as a safe, reliable, cost- and time-effective method for the reconstruction of various head and neck defects in children.     

3D‐Printed haptic “Reverse” models for preoperative planning in soft tissue reconstruction: A case report

In reconstructive surgery, preoperative planning is essential for optimal functional and aesthetic outcome. Creating a three‐dimensional (3D) model from two‐dimensional (2D) imaging data by rapid prototyping has been used in industrial design for decades but has only recently been introduced for medical application. 3D printing is one such technique that is fast, convenient, and relatively affordable. In this report, we present a case in which a reproducible method for producing a 3D‐printed “reverse model” representing a skin wound defect was used for flap design and harvesting. This comprised a 82‐year‐old man with an exposed ankle prosthesis after serial soft tissue debridements for wound infection. Soft tissue coverage and dead‐space filling were planned with a composite radial forearm free flap (RFFF). Computed tomographic angiography (CTA) of the donor site (left forearm), recipient site (right ankle), and the left ankle was performed. 2D data from the CTA was 3D‐reconstructed using computer software, with a 3D image of the left ankle used as a “control.” A 3D model was created by superimposing the left and right ankle images, to create a “reverse image” of the defect, and printed using a 3D printer. The RFFF was thus planned and executed effectively, without complication. To our knowledge, this is the first report of a mechanism of calculating a soft tissue wound defect and producing a 3D model that may be useful for surgical planning. 3D printing and particularly “reverse” modeling may be versatile options in reconstructive planning, and have the potential for broad application. © 2014 Wiley Periodicals, Inc. Microsurgery 35:148–153, 2015.     

头颈部组织缺损显微外科重建的临床效果

目的介绍头颈部组织缺损的显微外科重建技术及其临床应用效果。方法选用血管蒂较长和血管口径较粗的游离组织瓣供区，选择口径粗大和位置合适的受区血管，将游离瓣制备成外露瓣，以利于术后血供的监测，在手术放大镜下行血管吻合，部分病例同时吻合2根静脉，以确保游离瓣的静脉回流。结果施行1007例共1066块游离组织瓣移植修复头颈部组织缺损，临床成功率为98．3％，术后血管危象的发生率为3．1％，抢救成功率为45．5％。结论应用显微外科技术施行游离组织瓣移植重建头颈部组织缺损，可获得良好的临床效果。     

PR05POST‐OPERATIVE HAEMATOMAS IN MICROVASCULAR FREE FLAP RECONSTRUCTION OF THE HEAD AND NECK: THE INCIDENCE,AETIOLOGY AND OUTCOME MODIFICATIONS

Background Free tissue transfer using microvascular surgery has become a safe a reliable means to repair soft tissue and/or bony defects of the head and neck. Operative success reaches 98%, however the incidence of significant post‐operative complication is also relatively high (32%). One common and often severe complication is haematoma formation at either donor or recipient sites. The incidence of recipient site haematoma is reported at 6%, however the causes and outcomes of haematomas have not been well investigated. A retrospective historical analysis of both donor and recipient site wound haematoma was performed to identify causative factors and the effect on patient outcome. Methodology A five year review was conducted for microvascular free tissue transfer to defects in the head and neck at The Royal Melbourne Hospital, for the period from February 2001 until February 2006. The medical records of these 150 patients were reviewed for donor and recipient site wound haematoma and outcomes. Results Significant factors for the development of post‐operative haematomas included lood pressure control during the first post‐operative, correlating with the likelihood of developing either a donor or recipient site haematoma (p value < 0.001), drain‐tube outputs (both high and low), smoking and the use of pre‐operative NSAIDs. Conclusion There are significant reversible factors that contribute to the development of post‐operative haematomas in head and neck surgery. Close monitoring of patient blood pressure by theatre and recovery nursing staff, close monitoring of drain outputs, and pre‐operative counselling on the use of NSAIDs and smoking may all be useful in the prevention of haematoma formation.     

The observer‐based linear quadratic sub‐optimal digital tracker for analog systems with input and state delays

This paper presents a new observer‐based sub‐optimal digital tracker for the continuous‐time system with input and state time delays. We directly convert the continuous‐time input‐state delayed system into an equivalent discrete‐time input‐state delayed model and its extended discrete‐time delay‐free model. In addition, we directly discretize the linear quadratic performance index specified in the continuous‐time domain into an equivalent decoupled discrete‐time performance index using the newly developed extended delay‐free model. As a consequence, the well‐developed discrete‐time optimal control theory for discrete‐time delay‐free system can be applied to determine the optimal digital tracker for the continuous‐time input‐state delayed system. When the states of the continuous‐time input‐state delayed system are not available for measurements, we develop a sub‐optimal digital observer for the original continuous‐time input‐state delayed system using the state‐matching digital redesign technique and the digital‐to‐analog model conversion technique. As a result, the proposed observer‐based linear quadratic digital tracker is able to make the output of the digitally controlled continuous‐time input‐state delayed system sub‐optimally track the desired reference signals. An illustrative example is presented to demonstrate the effectiveness of the proposed design methodology. Copyright © 2003 John Wiley & Sons, Ltd.     

Reconstructive microsurgery in pediatric population-a series of 25 patients

Pediatric microsurgery procedures possess various difficulties when compared with adults. However, both free tissue transfers and replantation of the amputated parts show remarkable success rates in children. The concerns of survival of the flaps and the amputated parts have shifted to the function of these in the adulthood. Several key points and hints allow successfull rates for both survival and function. We present a series of microsurgical procedures both free tissue transfers (12 patients) and digital replantations (13 patients). Free tissue transfers included toe-to-hand transfers in 5, latissimus dorsi flaps in 4, fibular flaps in 4, and anterolateral thigh flaps in 2 patients. Thirteen patients involved 17 digital replantations. The survival rate was less in the replantation group (58.75%) than in the free tissue transfer group (93%). Both the functional and the cosmetic results were promising. The follow-up period was between 1 and 6 years (mean 37 months) for the free tissue transfer group and 1-5 years (mean 20 months) for the replantation group. The major technical difficulties include the age group of 0-2 years. Aside from these the high capacity of regeneration and the improved learning capacity increase the feasibility of the microsurgical procedures proceeded among children.     

Initial experience with personal digital assistant-based reflectance photoplethysmograph for free tissue transfer monitoring

Improved microsurgical technique has resulted in a high percentage of successful free tissue transfers. When a tissue transfer fails in the head and neck, however, the results are orocutaneous fistulas, carotid artery exposure, and deformity that adds morbidity, expense, and may delay adjuvant therapy. Postoperative monitoring of tissue perfusion can detect early problems in free tissue transfer that may allow for early intervention and salvage. The authors have demonstrated that reflectance photoplethysmography can detect perfusion changes in free tissue transfer within 5 minutes of a pedicle "insult" intraoperatively. Normative data for viable flaps from various donor sites have been established. The authors now report their initial experience with a newly developed reflectance photoplethysmograph based on a hand-held computer for routine clinical use. Their results are compared with a conventional surveillance protocol that included observation, bleeding to pin prick, and bedside duplex scanning of the vascular pedicle. In a series of 30 free tissue transfers (29 patients), there was one ischemic event (skin paddle loss only), which was detected by the monitor. The monitor was able to predict correctly (one flap) survival of a free tissue transfer even when duplex ultrasonic data were indicative of an absence of perfusion. Personal digital assistant-based photoplethysmography appears to be a promising device for bedside diagnosis of free tissue transfer viability or ischemia.     

Color doppler ultrasonography is a reliable predictor of free tissue transfer outcomes in head and neck reconstruction.

OBJECTIVE: The purpose of our investigation was to report our experience with a color flow doppler (CFD) ultrasonography for postoperative monitoring of free tissue transfers. METHODS: A retrospective analysis of head and neck free tissue transfers at a single institution between 2000 and 2005 (n = 84; 80 successful, 4 failures). CFD measured blood flow velocity (cm/sec) and resistance to flow in the pedicle vein and artery on postoperative days 1, 3, and 7. RESULTS: Analysis of artery/vein ratio revealed vascular congestion by postoperative day 3 which later resolved. In flap failures, there was a significant reduction (P < 0.05) in venous blood flow by postoperative day 3. Waveform morphology representing vascular resistance and origin of donor flap did not correlate with flap outcome (r(2) = 0.23 and 0.44 respectively). CONCLUSION: Postoperative monitoring of free tissue transfers may allow for detection of poor perfusion. CFD is an objective method of studying blood flow postoperatively. EBM rating: C-4.     

Free-tissue transfers for reconstruction of oromandibular area in children

Introduction: Currently, free‐tissue transfers are commonly used for various reconstructive purposes in adults. However, there is a lack of large series of free flap reconstruction in children, especially for reconstruction of oromandibular defects. Our study aims to share our experience in free‐flap reconstruction of some challenging pediatric cases. Materials and methods: Pediatric free‐flap interventions (<18‐year‐old) that were performed between 2000 and 2006 in our clinic were retrospectively evaluated. Eighteen free‐tissue transfers were performed in 17 pediatric cases. Epidemiologic data, etiology, defects, preferred free flaps, and results have been compared and analyzed. Results: A total of 17 patients (18 free flaps) were analyzed. Mean age was 10.4 years. The etiology was tumor in 11 cases, traffic accident in 5 cases, and gunshot in 1 case. Double‐flap transfer was performed to one patient with a devastating shotgun wound and single flap transfers to others. A total of 8 osseous flaps, 7 osteocutaneous flaps, and 3 septocutaneous flaps were transferred. Total superficial flap necrosis was encountered in one flap (5.8%) while partial superficial necrosis was seen on two flaps (11.7%). Sixteen of the 17 cases reconstructed, including the three cases with complications, resulted in good functional and cosmetic outcome. One case was lost in the sixth postoperative month due to septisemia during chemotherapy. All the surviving 16 cases acquired bony fusion, mastication, and speech in addition to good cosmetic results. Conclusion: Pediatric free‐tissue transfers are increasing due to the development of better equipment, finer surgical technique, and a better understanding of the unique characteristics of pediatric cases. In our opinion, high success rates with good cosmetic and functional results can be obtained if the specific requirements of the pediatric procedures are met. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.     

Locally applied hypothermia and microvascular muscle flap transfers.

The success rate for wound closure of grade III open tibia-fibula fractures with free muscle flaps is approximately 90%. Complications and loss of free flaps are due mainly to anastomotic problems, local anatomical considerations, or recipient vessel injuries, which prolong the ischemic time of the transferred free muscle tissue. We present the techniques used at the Shock Trauma Center of The Maryland Institute for Emergency Medical Services Systems (MIEMSS), which has allowed us a 100% success rate for the last 80 free muscle transfers performed. This surgical technique involves the use of locally applied hypothermia to decrease muscle metabolism and no-reflow phenomena. Representative cases are illustrated, which could have been failures because of increased ischemic time.     

An experimental investigation into the use of implanted thermocouples and differential thermometry as monitors for microvascular anastomoses

It has been suggested that direct monitoring of arterial temperature using implanted thermocouples, may have value as a clinical postoperative monitor for vascularized free tissue transfers, including those with no visible surfaces. This study evaluated the technique in experimental animals, using simple, inexpensive equipment. Mean arterial differential temperature changes, with ipsilateral (n = 20) and contralateral (n = 21) references, of 0.6 degrees C and 0.5 degrees C respectively, reliably indicated occlusion of the superficial femoral artery in situ. In epigastric island flaps, arterial occlusion (n = 24) produced mean arterial temperature changes of 0.5 degrees C, but changes after venous occlusion were not significantly greater than unoccluded base line fluctuation. Venous differential temperature did not change significantly after either arterial or venous occlusion. In six epigastric free flaps, success or failure could not be distinguished, as the wide variation in measurements in the four successful flaps overlapped the recordings in the two which failed. It was shown that the nearer to the body core, the less the temperature difference between arterial wall and periarterial tissue. Occlusion of deeply sited arteries produced little or no change in arterial temperature. In view of these findings and because of the invasive nature of the technique, the authors did not pursue it clinically.     

Noninvasive monitoring of tissue viability

Noninvasive monitoring techniques are procedures of little or no morbidity that may be repeated frequently to assess tissue viability. The ideal noninvasive technique would be safe, sensitive, reliable, reproducible, simple to use, and inexpensive. Although no such ideal technique yet exists, several currently available methods have clinical usefulness. Visual fluorescein, fluorescein photography, and surface fluorometry all work by the same principle. We prefer the surface fluorometer because of its greater sensitivity, the more objective nature of the data it provides, and the greater frequency with which it can be repeated. Ultrasound Doppler techniques are useful preoperatively in locating vessels and assessing their patency, and we have found the bidirectional Doppler quite helpful in the postoperative monitoring of replanted or revascularized digits. The laser Doppler, photoplethysmograph, and surface thermometer have not been as helpful in our experience. Transcutaneous oxygen measurement shows great promise for the postoperative monitoring of replants and free tissue transfers.