Femoral Artery Anastomoses Research Articles

Three-dimensional microscope skill acquisition: A randomised controlled study comparing two-dimensional laboratory microscope training, video gaming and virtual reality gaming

IntroductionFine microsurgical motor skill acquisition can be challenging. With increasing technological innovation the method of microsurgical skills acquisition may change. Studies show that laboratory-based microsurgical training programs on a 2D microscope significantly improves novice’s microsurgical skill acquisition. However, are these skills transferable to a 3D microscope or is gaming agility more important? We present a randomised control trial of three interventions, namely laboratory tabletop microscope training (LM), high-fidelity video gaming (Sony PlayStation 4 console) (VG) and high-fidelity virtual reality gaming (Sony PlayStation VR console) (VR) versus a control group. MethodsForty novice medical students were block randomised to four groups: control (no intervention) n=10, LM n=10, VG n=10 and VR n=10. Participants performed chicken femoral artery anastomosis using the Aesculap Aeos® 3D microscope platform at baseline and again after intervention. Performance was evaluated using a modified structured assessment of microsurgery skills (mSAMS) score, time taken to complete anastomosis and time for suture placement by two blinded independent assessors. ResultNo statistically significant difference was noted between the groups at baseline. There was a statistically significant improvement in the LM arm between baseline and post-training for mSAMS score and time for suture placement. In the VG, VR and control groups no statistically significant difference was observed. ConclusionOur study demonstrates that during early microsurgical training, an intense laboratory-based microsurgical training program significantly improves novice’s anastomotic performance on a 2D microscope, and these skills are transferable when a 3D anastomosis is carried out. However, focussed gaming had no significant effect, and the results were akin to the non-intervention group.

Effectiveness of 1α-25-dihydroxyvitamin D3 active substance on anastomosis safety in the rat femoral artery end-to-end anastomosis experimental model: Macroscopic and histological analyses

In inflammatory conditions, macrophage dominance affects the degree of inflammation. We assessed the effects of the active vitamin D (calcitriol) on inflammatory processes and macrophage dominance and aimed to determine the potential positive macroscopical and histological effects in the supermicrosurgical arterial anastomosis model of rats. Forty rats were divided into five groups: control surgery (Group 1), surgery with preoperative (Group 2), postoperative (Group 3) and peroperative (Group 4) systemic calcitriol, and surgery with local calcitriol (Group 5). Eighty femoral artery anastomoses were planned in both legs of rats. Systemic calcitriol was administered intraperitoneally to the relevant groups daily. Preoperative vessel diameter measurements were taken before anastomosis. Three weeks postsurgery, postoperative vessel diameter measurements were taken, anastomosis patency was assessed, and vascular segments were collected for histological examination, which included assessment of M1 and M2 macrophage depolarization, leucocyte infiltration, intima–media ratio, and luminal gap scoring. Systemic calcitriol administration (pre-, post-, or perioperative) significantly improved vessel diameter (p < 0.001); there was no significant difference among Groups 2–4. Histological findings revealed that Groups 3 and 4 had lower intima–media ratios (p < 0.05 and p < 0.01), higher M2-M1macrophage ratios (p < 0.01 and p < 0.001), and lower leucocyte infiltration (p < 0.05, p < 0.01, and p < 0.001). Local calcitriol administration had no vasodilatory effects or resulted in positive histological outcomes. Although the administration of calcitriol pre- and postoperatively increased vessel diameter, the latter appeared to have a more favorable impact on the histological analyses.

Histopathological Validation of Microvascular Anastomosis using Two-Throw Reef Knots - An Experimental Study.

Knot configuration is an important but relatively neglected topic in microvascular anastomosis literature. To study the differences between end-to-end microvascular anastomosis performed with two-throw reef knots as compared to traditional three-throw knots in a rat femoral artery model at the histological level. Sprague Dawley rats underwent end-to-end microvascular anastomosis of the right femoral artery (one-way-up method). The rats were divided into two groups: two-throw reef knots versus traditional three-throw knots. The patency was checked by the standard empty refill method. After 2 weeks, the rats underwent re-exploration. An anastomotic segment was sent for histological analysis. Histological alterations including luminal patency and changes in Tunica intima, Tunica media, and Tunica adventitia were compared between the two groups. Twenty-nine rats were operated on by the senior author (17 by three-throw and 12 by two-throw reef knots). In the two-throw reef knot group versus the traditional three-throw knot group, the immediate patency rates were 100% versus 82.4%, and the delayed patency rates were 90.9% versus 62.5%, respectively. The histopathological patency rates were concordant with delayed patency rates. Subintimal proliferation and fibrosis were comparable in both groups. Adventitial granulomas were noted in all, irrespective of the knotting technique. Tunica media preservation rates for the two-throw reef knot versus the traditional three-throw knot group were 63.6% versus 0%. Five rats were operated by the beginner in the field, all by two-throw reef knots (to assess the safety of this new method in the hands of a beginner). Microvascular anastomosis performed with two-throw reef knots appears not only feasible but better in terms of anastomosis patency. Histological superiority in terms of Tunica media preservation further validates the technique.

Experimental and numerical study of flow structure in a model of distal anastomosis of femoral artery

Physical and numerical simulation of the steady blood flow was carried out focusing on the distal end-to-side anastomosis of a graft to the femoral artery. The angle between the graft and the artery was 60°. Two Reynolds numbers were considered that corresponded to the physiological range when estimated using the average (Re = 240) and maximum (Re = 1640) blood flow through the human femoral artery over a single cardiac cycle. The experiment included flow visualization and measurements of instantaneous vector fields of velocity using an optical SIV (Smoke Image Velocimetry) technique. Direct numerical simulation (DNS) was employed for numerical study. The distribution of blood flows through the branches of the main artery was 80 % in the antegrade and 20 % in the retrograde direction. Main patterns in the distribution of velocity and its root-mean-square fluctuations in both branches of the main artery were revealed. Flow separation regions were observed in the branching area. Additionally, secondary flows (Prandtl’s vortices of the first kind) were revealed. The flow in the branching area was still laminar Re = 240, while the signs of transition to turbulence were documented within separation regions at Re = 1640. Distributions of streamwise and circumferential components of skin friction vector were estimated. In some regions of flow, these components were shown to be comparable in size. The location of regions was revealed in which the friction magnitude in the considered flow regimes was lower than the one in an unimpaired artery (developed laminar flow in a circular pipe) at appropriate Reynolds numbers.

Preliminary experience of autologous free myocutaneous flap combined with free dermal graft in the treatment of refractory empyema with bronchopleural fistula

ObjectivesTo explore the effects of autologous free dermal graft combined with free myocutaneous flap on bronchopleural fistula (BPF) with empyema, we summarized and analyzed two cases. MethodsTwo patients with refractory empyema and BPF were treated with autologous free dermal graft combined with free myocutaneous flap. The treatment included debridement of empyema, rib resection drainage, repair of bronchopleural fistula, and free vastus lateralis myocutaneous flap transplantation to eliminate the empyema. After the free dermal graft was harvested from the healthy skin around the incision, it was inserted into the fistula and sutured with the surrounding pleural tissue. The keys to the operation lies in the anastomosis of the lateral circumflex femoral artery (LCFA), vein and nerve that supply the vastus lateralis muscle flap to the thoracodorsal vessels and nerves. After surgery, the empyema, air leakage, and the survival of the myocutaneous flap were observed. ResultsThere was no disease recurrence after follow-up for seven and six months, respectively. Re-examination of the chest computed tomography (CT) or magnetic resonance imaging (MRI) indicated that the abscess cavity had disappeared. No necrosis of the myocutaneous flap was observed after surgery. ConclusionThe application of autologous free dermal graft combined with free vastus lateralis myocutaneous flap transplantation is effective in the treatment of patients with bronchopleural fistula with refractory chronic empyema, and the clinical effect is satisfactory.

An Unorthodox Vascular Surgical Approach to Save a Limb

A 33 year old male intravenous drug user was referred urgently with right groin haemorrhage and acute limb threatening ischaemia after superficial femoral artery (SFA) puncture. A ruptured SFA pseudoaneurysm was detected by colour duplex ultrasonography. Young age, synchronous presence of abscess (Pseudomonas aeruginosa isolates), extensive tissue damage, and lack of appropriate venous conduit favoured an end to end anastomosis (A and B, asterisk) of the profunda femoral artery (PFA) to the distal SFA stump. Meropenem was administered for 21 days and a vacuum assisted closure device helped with wound healing. Using this provocative technique, successful revascularisation and lower limb salvage were achieved.Image 1

A Novel Basic Training Laboratory Model on Live Subjects for Supermicrosurgery: Mouse Femoral Artery, Vein and Nerve

BACKGROUNDIncreasing success rates of supermicrosurgery operations have increased the importance of developing the ideal training model for super-microsurgery. Working on the model is very important for increasing and continuing microsurgery and supermicrosurgery skills. We aimed to present a standardized, simple and easy to access live training model for supermicrosurgery.METHODSThe experiment was performed in the University of Health Sciences, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, IDEA, Istanbul, Turkey in 2020. Twelve BALB/c male albino mice weighing 20-45 gr were used in the study. Unilateral femoral artery, vein and nerve diameters of mice were measured. Anastomosis was performed on the bilateral femoral vessels. The surgical procedure times were also recorded.RESULTSThe mean weight of the mice was 36.6 ± 6.09 gr, the length was 15.10 ± 1.10 cm. The mean external diameter of the femoral artery, vein and nerves were 0.31 ± 0.34 mm, 0.48 ± 0.70 mm, 0.38 ± 0.43 mm, respectively. The mean preparation time of neurovascular structures for anastomosis was 15.75 ± 1.54 min, mean femoral artery and vein anastomosis time was 24.91±1.72 and 33.16±1.74 min, respectively. Vascular patency was detected as 100% after all vascular anastomosis procedures.CONCLUSIONMice femoral neurovascular structures are similar to rats in terms of basic morphology, and they are small enough for super-microsurgery education model. Dissection of mice femoral bundles are easy to perform. In terms of training models, anesthetic requirement and laboratory costs are less for mice, and handling them is much easier compared to rats; thus, making them especially suitable for basic supermicrosurgery training courses.

The effect of mesenchymal stem cells lyophilisate on femoral artery of rat anastomosis: A histopathological and histomorphometric study

Background and objectiveMesenchymal Stem Cells (MSCs) are well known for their tissue regeneration enhancing effect and their contribution to immune regulation. However, their contribution to the healing process of femoral artery anastomosis, especially to endothelialization, has not been studied sufficiently in the clinic. This study was carried out to evaluate the effects of MSC-lyophilisate from the human umbilical cord on anastomosis experimental study in rats histopathologically. MethodAfter intraperitoneal anesthesia was applied to the rats, the femoral artery was exposed with a 2 cm incision in the right femoral region. After the artery was cut in the experiment and sham groups, femoral artery end-to-end anastomosis was performed using the primary suture technique. MSC-lyophilisate was poured in powder form onto the anastomosed outer surface of the vessel in the treatment group and saline solution was poured to the sham group. No intervention was made to the control group. The data analysis was performed with IBM SPSS Statistics 25. ResultsIn the experiment group, flattening of the inner elastic lamina, morphological changes and vacuolization in the muscle fibers, inflammation in the adventitia and significant vascular wall thickening were observed in the femoral arteries of the rats after the intervention. According to the histopathological scoring results, tissue samples belonging to sham and experimental groups showed marked pathological findings such as endothelial damage, flattened areas where the folded structure in the inner elastic lamina disappeared, muscle fiber degeneration and inflammation in the adventitia. ConclusionHuman umbilical cord-origin MSC-lyophilisate application holds an important place in femoral artery surgery. We evaluate that it will be meaningful to determine the MSC-lyophilisate dose for hemostasis without creating thrombus after anastomosis. MSC-lyophilisate will be used to provide hemostasis in areas with local bleeding in the future. In addition, it is recommended to make plans for an in-depth examination of possible problems and cases in future studies.

How to Build OP-MEG: Specific Issues and Challenges

Symptomatic innominate artery stenosis presenting as hemodynamic bilateral cerebral ischemia is uncommon. We present a rare case of the severe stenosis of the origin of an innominate artery and severe stenosis of bilateral internal carotid artery that induced hemodynamic cerebral ischemia after ipsilateral axillary artery-bilateral femoral artery bypass and was treated with stent replacement of the innominate artery and right internal carotid artery.A 64-year-old woman who previously had undergone right axillary artery-bilateral femoral artery anastomosis for abdominal aorta high obstruction had been suffering from chronic dizziness and so visited our department. Findings of the examination included the severe stenosis of the origin of an innominate artery and severe stenosis of bilateral internal carotid artery, causing hemodynamic cerebral ischemia. She underwent stent replacement of the innominate artery and right carotid artery stenting via a right transbrachial approach. Her symptoms were relieved postoperatively.For the sake of improving the hemodynamic cerebral ischemia, we performed stent replacement for innominate artery stenosis and right carotid artery stenting. Endovascular treatment of subclavian and innominate artery disease is a safe procedure. In addition, for the protection of thromboembolic migration, we performed balloon protection of the external carotid artery and filter protection of the internal carotid artery.Stent replacement for these lesions can be performed safely with the right approach and protection methods, even when the only accessible route is the right brachial artery.

The Effect of Very Low Concentrations of Ethanol on Microvascular Artery and Vein Anastomosis: An Experimental Study

Objectives This study investigated the effect of very low concentrations of ethanol on artery and vein anastomosis. Also, it was aimed to determine the appropriate ethanol concentration to be used in vasospasm. Methods Rats were divided into five groups of eight rats, each group, as follows: Group i: saline; Group ii: 2.5% ethanol; Group iii: 5% ethanol; Group IV: 7.5% ethanol; and Group V: 10% ethanol. During the femoral artery and vein anastomosis, 1ml of the agent was used for irrigation in each group. Vessel diameters were measured before the anastomosis, at the fifth and 15th minutes, and the third week after the anastomosis. Histopathological samples were taken in the third week. Results In Groups ii and iii, the mean vessel diameters were found to increase 15th minute. Also observed was an increase in mean vessel diameter that continued in the third week. Although acute vasodilation was detected in Groups IV and V, arterial and venous thrombosis was observed in the third week. Intima and media thickness decreased in Group ii, while it increased in Group iii. Perivascular inflammation and fibrosis increased as the ethanol concentration increased. Conclusion 2.5% ethanol causes acute and prolonged vasodilation and does not cause endothelial cell damage, perivascular inflammation, and fibrosis. 2.5% ethanol will be a powerful alternative use in many situations that occur with vasospasm.

3D-printed cranial models simulating operative field depth for microvascular training in neurosurgery.

Background: The skills required for neurosurgical operations using microsurgical techniques in a deep operating field are difficult to master in the operating room without risk to patients. Although there are many microsurgical training models, most do not use a skull model to simulate a deep field. To solve this problem, 3D models were created to provide increased training in the laboratory before the operating room, improving patient safety.Methods: A patient’s head was scanned using computed tomography. The data were reconstructed and converted into a standard 3D printing file. The skull was printed with several openings to simulate common surgical approaches. These models were then used to create a deep operating field while practicing on a chicken thigh (femoral artery anastomosis) and on a rat (abdominal aortic anastomosis).Results: The advantages of practicing with the 3D printed models were clearly demonstrated by our trainees, including appropriate hand position on the skull, becoming comfortable with the depth of the anastomosis, and simulating proper skull angle and rigid fixation. One limitation is the absence of intracranial structures, which is being explored in future work.Conclusion: This neurosurgical model can improve microsurgery training by recapitulating the depth of a real operating field. Improved training can lead to increased accuracy and efficiency of surgical procedures, thereby minimizing the risk to patients.

Free vastus lateralis muscle flap transplantation for postoperative chronic empyema: retrospective analysis of eight case series.

Postoperative chronic empyema (PPE) remains a complex challenge for thoracic surgeons. We retrospectively investigated patients with PPE who were treated with free vastus lateralis muscle flap transplantation, and report our results. Eight patients with PPE and persistent bronchopleural fistula (BPF) treated in our hospital from January 2015 to June 2019 were retrospectively analyzed, the time since onset of empyema ranged from 5 to 72 months. The operation was performed in two stages, stage I surgery included empyema debridement, rib resection drainage or open-window thoracostomy (OWT), meanwhile, BPF was treated under bronchoscope. Stage II surgery included obliteration of the pleural space by free muscle flap transplantation. The keys to the operation are thorough debridement, closure of the BPF, and complete obliteration of the residual pleural space. The challenge lies in the anastomosis of the lateral femoral circumflex artery and vein that supply the vastus lateralis muscle flap to the thoracodorsal vessels. The free muscle flaps survived in all eight patients. The abscess cavity was completely obliterated with the muscle flap. Good efficacy was achieved with primary wound healing. No serious perioperative complications were reported. No empyema recurrence, atrophy, infection, or necrosis of the muscle flap was seen during the 18- to 72-month follow-up. The vastus lateralis muscle flap has a large volume with good blood supply and strong antibacterial ability. It can be used for effective obliteration of a large residual cavity caused by empyema and maintains a good thoracic shape. It is an ideal choice for the treatment of postoperative chronic refractory empyema.

Large and Uneven Bites in End-to-End Anastomosis of the Rat Femoral Artery.

Successful microvascular anastomosis depends on sutures that adequately oppose both cut vessel edges. Trainees tend to take oversized or uneven bite. To improve early microsurgical skill acquisition using the rat, this study tests the belief that such bites compromise early patency by applying exaggerated bites to end-to-end arterial anastomoses. Twelve Sprague-Dawley rats were randomly assigned to one of the four bite techniques to be applied to both femoral arteries (mean diameter, 0.8 mm). Large (L) and standard (S) bites measured 1.0 and 0.2 mm from the edge, respectively. Eight simple interrupted anastomoses were performed per bite technique, each labeled according to every proximal end bite size, followed by every distal end bite size: LL, LS, SL, and SS. Anastomosis time and blood flow rates were recorded and analyzed statistically. After sacrifice 5 days postoperation, anastomosis sections of each technique were examined histologically. All 24 anastomoses (100%) maintained patency for 5 days. There was no statistical difference between all postoperative blood flow measurements at any given time. Anastomosis times using LL, LS, SL, and SS bite techniques were 41.6, 33.2, 34.8, and 25.5 minutes, respectively. Anastomosis time for the traditional bite technique (SS) was significantly shorter than all other bite techniques (p < 0.05). Histological examination of the harvested segments from each group revealed similar pathophysiological features. Oversized bites (1 mm), placed symmetrically and asymmetrically across the anastomosis, do not affect early patency in the rat femoral artery. A reduced reliance on conventional guidelines for suture bites appears acceptable during microarterial anastomoses if the goal is vessel patency. However, we believe clinical competence involves the ability to place small, even bites consistently and uniformly. During microsurgical training, the occasional large bite need not be replaced; however, the trainee should be encouraged to take standard bites.

Undergraduate microsurgical training: a preliminary experience.

Microsurgical training is organised almost exclusively in a post-graduate setting, usually for residents of various surgical specialities. The aim of this study was to present an undergraduate microsurgical training model directed toward medicine students of clinical years. Curriculum design and results. Two six-participant groups of students interested in training were recruited. The programme consisted of 15 three-hour classes (2 hours' work under the microscope) and divided into basic and advanced training parts. The simulation model used in this course was a chicken thigh. The basic training programme consisted of placing sutures on a latex glove followed by preparation of a chicken thigh neurovascular bundle and performing femoral nerve and artery anastomoses. The advanced part of the training consisted of practising the acquired skills and the introduction of new techniques such as end-to-side arterial anastomosis, artery and nerve repair with vein conduit. A "6-stitches test" was used as an outcome measure of the acquired microsurgical skills. After 15 weeks and 30 hours of training and performing 31 anastomoses the undergraduate microsurgical course was completed. CONCLUSION: The results of this study show that the undergraduate, facultative microsurgical training is effective in acquiring microsurgical skills, competence and confidence for participating students.

The Flower Petal Training System in Microsurgery

Despite hundreds of training models for microsurgery being available in the literature, very few of them are scientifically validated. We chose to validate our low-fidelity training model on flower petals by comparing it head-to-head with a moderate fidelity training model, the anastomosis on chicken leg femoral artery. A total of 16 participants of different levels of expertise were randomized into 2 groups, 1 training on flower petals and 1 on chicken leg femoral arteries. The groups were evaluated on performing a rat femoral artery anastomosis using the validated Stanford Microsurgical Assessment (SMaRT) Scale. The Mann-Whitney U test was used to check for statistically significant differences between the groups. The flower petal sutures were also evaluated and Pearson correlation was used to check for associations between better petal anastomosis scores and better final SMaRT results. After 6 weeks of flower petal training, microsurgical trainees had significantly better overall SMaRT scores than trainees using chicken leg training, better fine tissue feeling, and better scores in knot tying. The anastomosis times for the rat femoral arteries did not differ between the 2 groups. Good scores for flower petals strongly correlated with a better SMaRT score for the anastomosis. The number of rats used in training reduced after the implementation of this model in continuous training. The flower petal technique, despite being a low-fidelity model, shows superiority in developing fine tissue feeling and improved knot tying in microsurgery beginners and intermediate level practitioners adding this training model to their program. Further research needs to establish if the improvements also apply to already seasoned microsurgeons and whether the petal score has predictive value for future clinical application.

Can Smartphones Be Used to Perform Video-Assisted Microanastomosis? An Experimental Study.

Smartphone cameras are continuously improving. The present study aimed to evaluate the possibility of using smartphones' magnification system to perform microanastomosis in rats. Fifteen rats were randomly divided into 3 groups, according to the magnification system used: Microscope, iPhone 7 smartphone, and Galaxy S7 smartphone. In the microscope group, a DFVasconcelos microsurgery microscope was used. In both smartphone groups, the magnifications systems were connected to a 55-inch television through the mirror function. Animals in both groups underwent femoral artery anastomosis in the right forepaw and femoral nerve neurorrhaphy in the left hindleg. The body weight, arterial and nerve caliber, and anastomosis time and patency were immediately analyzed. No significant differences were observed between the groups regarding body weight, arterial, or nerve caliber. The smartphones did not provide a sufficient quality of image for an adequate identification of the arterial walls. Therefore, neither arterial anastomosis nor neurorrhaphy could be completed, even after 3 hours of surgery. The first steps toward anastomosis or raffia were performed with difficulty. The current video resolution and lack of stereoscopic image of available smartphones is not sufficient to perform video-assisted anastomosis of femoral arteries or nerves.

Acquisition of basic microsurgery skills using home-based simulation training: A randomised control study

Acquisition of fine motor skills required in microsurgery can be challenging in the current training system. Therefore, there is an increased demand for novel training and assessment methods to optimise learning outside the clinical setting. Here, we present a randomised control trial of three microsurgical training models, namely laboratory tabletop training microscope (Laboratory Microscope, LM), low-cost jewellers microscope (Home Microscope, HM) and iPad trainer (Home Tablet, HT). Thirty-nine participants were allocated to four groups, control n=9, LM n=10, HM n=10 and HT n=10. The participants performed a chicken femoral artery anastomosis at baseline and at the completion of training. The performance was assessed as follows: structured assessment of microsurgery skills (SAMS) score, time taken to complete anastomosis and time for suture placement. No statistically significant difference was noted between the groups at baseline. There was a statistically significant improvement in all training arms between the baseline and post-training for SAMS score, time taken to complete the anastomosis and time per suture placement. In addition, a reduction was observed in the leak rate. No statistical difference was observed among the training arms. Our study demonstrated that at the early stages of microsurgical skill acquisition, home training using either the jewellers microscope or iPad produces comparable results to laboratory-based training using a tabletop microscope. Therefore, home microsurgical training is a viable, easily accessible cost-effective modality that allows trainees to practice and take ownership of their technical skill development in this area.

A Comparison of the Minimal-Touch Technique and the Eversion Technique for Microvascular Anastomosis in a Rat Model

Background During microvascular anastomosis, needle placement is facilitated by inserting the tips of the forceps into the lumen of the vessel, rather than grasping and everting the luminal wall, to minimize trauma to the vessel. This study examines whether the vessel wall can be grasped and everted during microvascular anastomosis without compromising surgical outcomes. Methods A total of 20 Sprague-Dawley rats weighing between 252 and 483 g were used. Bilateral anastomoses of the animals' femoral arteries (mean size: 0.90 mm) were performed using two different techniques: the classic minimal-touch approach and the eversion technique. The first 10 animals were survived for 48 hours and the second 10 animals were survived for 2 weeks. Patency was assessed immediately after surgery and just before sacrifice. Hematoxylin and eosin stains were performed and each anastomosis scored according to a grading rubric assessing endothelial cell loss, neointimal proliferation, medial necrosis, adventitial inflammation, and inflammation thickness. Results The patency rates of both techniques were identical (100%). There was no difference in the patency rates of anastomoses evaluated 48 hours after surgery (100%) and 2 weeks after surgery (100%). Histological outcomes between the minimal-touch technique and the eversion method were similar. The thickness of adventitial inflammation at 2 weeks was the only outcome found to be statistically different (p = 0.046) between the two treatments and this difference favored the eversion technique (i.e., less inflammation thickness). Conclusion The eversion method of performing microvascular anastomosis provides comparable results to the classic minimal-touch approach in rat femoral artery anastomoses.

The learning rate in three dimensional high definition video assisted microvascular anastomosis in a rat model

Three-dimensional (3D) high definition (HD) video systems are changing microsurgical practice by providing stereoscopic imaging not only for the surgeon and first assistant using the binocular microscope, but also for others involved in the surgery. The purpose of this study was to evaluate the potential to replace the binocular microscope for microarterial anastomoses and assess the rate of learning based on surgeons' experience. Two experienced and two novice microsurgeons performed a total of 88 rat femoral arterial anastomoses: 44 using a 3D HD video device ('Trenion', Carl Zeiss Meditech) and 44, a binocular microscope. We evaluated anastomosis time and modified OSATS scores as well as the subjects' preference for comfort, image adequacy and technical ease. Experienced microsurgeons showed a steep learning curve for anastomosis times with equivalent OSATS scores for both systems. However, prolonged anastomosis times were required when using the novel 3D-HD system rather than direct binocular vision. Comparable learning rates for anastomosis time were demonstrated for novice microsurgeons and modified OSATS scores did not differ between the different viewing technologies. All microsurgeons reported improved comfort for the 3D HD video system but found the image quality of the conventional microscope superior, facilitating technical ease. The present study demonstrates the potential of 3D HD video systems to replace current binocular microscopes, offering qualitatively-equivalent microvascular anastomosis with improved comfort for experienced microsurgeons. However, image quality was rated inferior with the 3D HD system resulting in prolonged anastomosis times. Microsurgical skill acquisition in novice microsurgeons was not influenced by the viewing system used.

Heads-up 3D Microscopy: An Ergonomic and Educational Approach to Microsurgery.

Traditional microsurgery can lead surgeons to use postures that cause musculoskeletal fatigue, leaving them more prone to work-related injuries. A new technology from TrueVision transmits the microscopic image onto a 3-dimensional (3D) monitor, allowing surgeons to operate while sitting/standing in a heads-up position. The purpose of this study was to evaluate the feasibility of performing heads-up 3D microscopy as a more ergonomic alternative to traditional microsurgery. A feasibility study was conducted comparing heads-up 3D microscopy and traditional microscopy by performing femoral artery anastomoses on 8 Sprague-Dawley rats. Operative times and patency rates for each technology were compared. The 8 microsurgeons completed a questionnaire comparing image quality, comfort, technical feasibility, and educational value of the 2 technologies. Rat femoral artery anastomoses were successfully carried out by all 8 microsurgeons with each technology. There was no significant difference in anastomosis time between heads-up 3D and traditional microscopy (average times, 34.5 and 33.8 minutes, respectively; P = 0.66). Heads-up 3D microscopy was rated superior in neck and back comfort by 75% of participants. Image resolution, field of view, and technical feasibility were found to be superior or equivalent in 75% of participants, whereas 63% evaluated depth perception to be superior or equivalent. Heads-up 3D microscopy is a new technology that improves comfort for the microsurgeon without compromising image quality or technical feasibility. Its use has become prevalent in the field of ophthalmology and may also have utility in plastic and reconstructive surgery.