Safety and efficacy of Symani robotic-assisted microsurgery: Assessment of vascular anastomosis patency, thrombus, and stenosis in a randomized preclinical study.

INTRODUCTION: The Symani surgical system undergoes scrutiny in this study as part of a series of preclinical investigations. Previous studies compared the precision of robotic-assisted anastomoses with manual techniques. This study aimed to evaluate the critical, histological, and gross parameters at the site of anastomosis and at distant sites in a rat model to provide insights into the safety and efficacy of robotic-assisted microsurgery to enhance its potential for clinical adoption. MATERIALS AND METHODS: Experienced microsurgeons performed arterial and venous anastomoses in 16 Wistar rats, randomized into four treatment groups: robotic artery, robotic vein, manual artery, and manual vein. Various parameters were evaluated at two time points (T0 and T30) on the day of the procedure and at Day 28 (T28d). In the second phase of the study, the animals underwent necropsy, histopathologic analysis, micro-CT scans, and angiography imaging of the anastomosis sites, major organs, and distant target organs by a blinded assessor. RESULTS: Patency rates were 100% at T0 and T30 for all anastomoses and stayed at 100% on T28d for the robotic subgroups; however, it decreased to 87.5% for manual arterial anastomoses owing to a case of obstructive thrombus. No evidence of clot migration was observed. Blood flow parameters and procedure times did not differ significantly. The blinded semiquantitative histological analysis revealed no significant disparities between the robotic and manual anastomoses across various pathological indicators. No gross abnormalities were detected in musculoskeletal examinations. CONCLUSION: This preclinical study demonstrated the safety of the Symani surgical system. Results suggest equivalence between robotic and manual techniques regarding thrombus formation at the anastomotic site and distal organs.

Microsurgical robotic system enables the performance of microvascular anastomoses: a randomized in vivo preclinical trial.

Technical advances in microsurgery have enabled complex oncological reconstructions by performing free tissue transfers, nerve and lymphatic reconstructions. However, the manual abilities required to perform microsurgery can be affected by human fatigue and physiological tremor resulting in tissue damage and compromised outcomes. Robotic assistance has the potential to overcome issues of manual microsurgery by improving clinical value and anastomoses' outcomes. The Symani Surgical System, a robotic platform designed for microsurgery, was used in this in-vivo preclinical study using a rat animal model. The tests included anastomoses on veins and arteries performed by microsurgeons manually and robotically, with the latter approach using Symani. The anastomoses were assessed for patency, histopathology, and execution time. Patency results confirmed that the robotic and manual techniques for venous and arterial anastomoses were equivalent after anastomosis, however, the time to perform the anastomosis was longer with the use of the robot (p < 0.0001). Histological analysis showed less total average host reaction score at the anastomotic site in robotic anastomosis for both veins and arteries. This study demonstrates the equivalence of vessel patency after microsurgical anastomoses with the robotic system and with manual technique. Furthermore, robotic anastomosis has proven to be slightly superior to manual anastomosis in terms of decreased tissue damage, as shown by histological analysis.

First-in-Human Free Flap Tissue Reconstruction Using a Dedicated Microsurgical Robotic Platform.

BACKGROUND: Microsurgery has become standard of care for increasingly complex techniques in tissue harvest, replantation, reconstruction, allotransplantation, and supermicrosurgery on submillimetric vessels. As techniques become more challenging and are performed at smaller and smaller scale, there is greater potential application for robotic assistance in extreme motion scaling and tremor reduction. METHODS: The Symani Surgical System (Medical Microinstruments, S.p.A, Calci, Pisa, Italy), a robotic platform designed for microsurgery, was used in a robot-assisted microsurgical free flap reconstruction using a perforator-to-perforator flap technique. This procedure utilized robot-assisted anastomosis of an artery and vein. RESULTS: The procedure was completed successfully, with vessels fully patent immediately following and 20 minutes after anastomosis. The flap was viable, no re-exploration of the anastomosis was necessary postoperatively, and no flap loss occurred. CONCLUSIONS: This novel, dedicated robotic platform with wristed microsurgical instruments was shown to be feasible for carrying out robot-assisted anastomosis of veins and arteries less than 0.8 mm in diameter, in the domain of supermicrosurgery. The system has the potential to open the field of microsurgery to new clinicians and to facilitate new microsurgical applications that were previously rendered inaccessible by the limits of manual precision and physiological tremor.

New Robotic System with Wristed Microinstruments Allows Precise Reconstructive Microsurgery: Preclinical Study.

BACKGROUND: Microsurgery allows complex reconstruction of tissue defects after oncological resections or severe trauma. Performing these procedures may be limited by human tremor, precision, and manual dexterity. A new robot designed specifically for microsurgery with wristed microinstruments and motion scaling may reduce human tremor and thus enhance precision. This randomized controlled preclinical trial investigated whether this new robotic system can successfully perform microsurgical needle driving, suturing, and anastomosis. METHODS: Expert microsurgeons and novices completed six needle passage exercises and performed six anastomoses by hand and six with the new robot. Experienced microsurgeons blindly assessed the quality of the procedures. Precision in microneedle driving and stitch placement was assessed by calculating suturing distances and angulation. Performance of microsurgical anastomoses was assessed by time, learning curves, and the Anastomosis Lapse Index score for objective performance assessment. RESULTS: Refined precision in suturing was achieved with the robot when compared with the manual technique regarding suture distances (p = 0.02) and angulation (p < 0.01). The time required to perform microsurgical anastomoses was longer with the robot, however, both expert and novice microsurgeons reduced times with practice. The objective evaluation of the anastomoses performed by novices showed better results with the robot. CONCLUSIONS: This study demonstrated the feasibility of performing precise microsutures and anastomoses using a new robotic system. Compared to standard manual techniques, robotic procedures were longer in time, but showed greater precision.

A Safer Way to Harvest a Superthin Perforator Flap.

SUMMARY: The updated knowledge of perforasome anatomy and the evolution of microsurgical techniques have enabled surgeons to safely harvest a thin flap. Recently, the anterolateral thigh perforator flap, the current workhorse in soft-tissue reconstruction, has started to be designed and harvested on the superficial fascia, which divides the deep from the superficial fat. This allows elevation of a very thin flap tailored to the defect. Faithful to the ultrathin concept, in an attempt to make flap dissection simpler and safer, the authors describe a revisited harvesting technique of superthin anterolateral thigh perforator flap. This study presents the outlined technique performed in 16 patients with complex soft-tissue defects after trauma or tumor ablation. All of them underwent primary reconstruction using superthin anterolateral thigh perforator free flaps by superficial fascia elevation harvested according to the described surgical procedure. Complications and functional outcomes were assessed. The authors' series of anterolateral thigh perforator superthin flaps demonstrated an overall 100 percent survival rate. Of 16 anterolateral thigh perforators, 12 (75 percent) had no complications and four (25 percent) had minor complications. No major complications such as total flap loss requiring additional salvage surgery were reported. In no case was secondary debulking performed. The superthin anterolateral thigh perforator flap harvested with the described approach was used successfully in microsurgical reconstruction, providing an excellent outer skin cover tailored to the defect. The dissection procedure was safe, quick, simple, and free of major complications. With minimal donor- and recipient-site morbidity, it provided great aesthetic results, avoiding secondary operations. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Propeller Flaps in the Upper Extremity: Arm and Forearm Reconstruction.

The propeller flap is an island of skin that is raised on its pedicle (most commonly a single perforator) and can rotate 180 degrees to cover a soft tissue defect. Thanks to these features, the propeller flap brings reliable tissue from outside of the zone of injury while sparing the main vessels of the upper extremity. This technique limits the donor site to the same limb, captures skin characterized by having the same color and texture, does not necessarily need a microvascular anastomosis, and overall reduces the operating time and surgical cost. Our intent here is to present 27 cases with different soft tissue defects of the upper arm and forearm that have been successfully reconstructed using propeller flaps. The surgical technique, with emphasis on the anatomy of the upper arm, is described. In particular, use of a freestyle approach to customize a perforator-based propeller flap to cover defects from small to medium size is detailed. In our experience, the use of a perforator propeller flap in the upper extremity for resurfacing represents both a very reliable and aesthetically pleasant option.

The rat model in microsurgery education: classical exercises and new horizons.

Microsurgery is a precise surgical skill that requires an extensive training period and the supervision of expert instructors. The classical training schemes in microsurgery have started with multiday experimental courses on the rat model. These courses have offered a low threat supervised high fidelity laboratory setting in which students can steadily and rapidly progress. This simulated environment allows students to make and recognise mistakes in microsurgery techniques and thus shifts any related risks of the early training period from the operating room to the lab. To achieve a high level of skill acquisition before beginning clinical practice, students are trained on a comprehensive set of exercises the rat model can uniquely provide, with progressive complexity as competency improves. This paper presents the utility of the classical rat model in three of the earliest microsurgery training centres and the new prospects that this versatile and expansive training model offers.

Posterior interosseous artery perforator-free flap: treating intermediate-size hand and foot defects.

INTRODUCTION: Ambiguous defects on the hand and foot, especially on the fingers and toes, are still challenging to treat despite achievements in reconstruction. AIM: The purpose of this study was to evaluate the use of the posterior interosseous artery perforator flap for resurfacing intermediate-sized defects and provide adequate coverage over tendons and bones. METHOD: Between October 2008 and March 2013, a total of 19 patients with soft-tissue defects on the hand or foot were treated. Flap elevation, anatomy, and clinical progress were evaluated. RESULT: All flaps survived and covered the defects, which ranged in area from 12 to 45 cm(2). The freestyle approach was used to harvest the flaps. The average length of the pedicle was 2.5 cm, and the pedicle was harvested without affecting the source vessel. The average diameter of the artery was 0.8 mm, and the average thickness of the flap was 3.5 mm. Anastomosis was performed either end-to-end on the perforator, or end-to-side on deep vessels. No subsequent thinning or surgical flap correction was necessary. Ambulation was allowed at 3 days postsurgery. The donor site was closed primarily to leave an acceptable donor site. DISCUSSION: A posterior interosseous artery perforator-free flap is a suitable choice for intermediate-size defects that are too large to cover using a local flap or too small for a first-line perforator flap. Up to 45 cm(2) of adequate coverage can be provided using a thin posterior interosseous artery perforator-free flap that does not require additional debulking. The disadvantages of a short pedicle can be overcome using perforator-to-perforator supermicrosurgery.