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

Microsurgical training using an ex-vivo model: microscope vs 3D exoscope

Objective

The aim of this study is to evaluate the feasibility of the 3D exoscope in a microvascular anastomosis training setting and compare it with the gold-standard technique using the operating microscope (OM).

Methods

Participants were recruited among otorhinolaryngology head and neck surgery (OHNS) residents of two tertiary care hospitals. Trainees were asked to complete 4 microvascular end-to-end anastomoses on chicken thighs with the OM and VITOM 3D exoscope. The performances were scored by experienced microvascular surgeons; an objective evaluation of the anastomosis and a subjective assessment of the workload were conducted.

Results

8 OHNS residents were recruited. Considering the amount of time needed to complete (TTC) the anastomosis, an improvement was shown by all the participants throughout the training program. The objective evaluation of the anastomosis did not show a significant difference. No significant differences were found by analyzing the subjective workload with the different tools.

Conclusions

This article represents the first attempt to compare the use of the OM and the 3D exoscope during training for microsurgery. The results of our study demonstrate the noninferiority of microsurgical training obtained using the 3D exoscope compared to that offered by the OM.

A Comparison of the Use of Two-Dimensional and Three-Dimensional Visualization Systems by Novice and Experienced Microsurgeons in Microsurgical Vessel Anastomosis: An Analysis Using the Chicken Model

BACKGROUND

 Various studies have discussed the benefits of applying three-dimensional (3D) techniques, specifically its advantages with respect to ergonomics, feasibility, and the rate of learning achievable in microsurgery training. However, no study has been conducted that compares the operator experience of using two-dimensional (2D) and 3D systems in microsurgical training. The aim of this study is to compare 2D- and 3D-assisted microsurgical training in novices based on anastomosis of chicken femoral arteries.

METHODS

 The participants were grouped by previous microsurgical experience. Group A includes novice participants. Group B includes 2D-experienced participants. Group C includes both participants in groups A and B. A questionnaire composed of 10 parameters in the field of image quality, dexterity, ergonomic, and feasibility will be filled out after each participant finished their anastomoses by the 2D and 3D systems.

RESULTS

 The results demonstrated 3D system was scored better on "field of view" (p = 0.004), "less tremor" (p = 0.005), "neck/upper back comfort" (p = 0.043), "lower back comfort" (p = 0.015), "technical feasibility" (p = 0.020), and "educational feasibility" (p = 0.004) in group A (N = 12). In group B (N = 9), 3D system was scored better on "field of view" (p = 0.041) but worse on "image resolution" (p = 0.031).

CONCLUSION

 With the 3D visualization system for microsurgical anastomosis of chicken femoral model, there are significant improvements in the field of view, stability, ergonomics, and educational value compared with 2D system among all participants. Accordingly, 3D-assisted microsurgery training can be a novel and potential popular training method.

Comprehensive review of surgical microscopes: technology development and medical applications

SIGNIFICANCE

Surgical microscopes provide adjustable magnification, bright illumination, and clear visualization of the surgical field and have been increasingly used in operating rooms. State-of-the-art surgical microscopes are integrated with various imaging modalities, such as optical coherence tomography (OCT), fluorescence imaging, and augmented reality (AR) for image-guided surgery.

AIM

This comprehensive review is based on the literature of over 500 papers that cover the technology development and applications of surgical microscopy over the past century. The aim of this review is threefold: (i) providing a comprehensive technical overview of surgical microscopes, (ii) providing critical references for microscope selection and system development, and (iii) providing an overview of various medical applications.

APPROACH

More than 500 references were collected and reviewed. A timeline of important milestones during the evolution of surgical microscope is provided in this study. An in-depth technical overview of the optical system, mechanical system, illumination, visualization, and integration with advanced imaging modalities is provided. Various medical applications of surgical microscopes in neurosurgery and spine surgery, ophthalmic surgery, ear-nose-throat (ENT) surgery, endodontics, and plastic and reconstructive surgery are described.

RESULTS

Surgical microscopy has been significantly advanced in the technical aspects of high-end optics, bright and shadow-free illumination, stable and flexible mechanical design, and versatile visualization. New imaging modalities, such as hyperspectral imaging, OCT, fluorescence imaging, photoacoustic microscopy, and laser speckle contrast imaging, are being integrated with surgical microscopes. Advanced visualization and AR are being added to surgical microscopes as new features that are changing clinical practices in the operating room.

CONCLUSIONS

The combination of new imaging technologies and surgical microscopy will enable surgeons to perform challenging procedures and improve surgical outcomes. With advanced visualization and improved ergonomics, the surgical microscope has become a powerful tool in neurosurgery, spinal, ENT, ophthalmic, plastic and reconstructive surgeries.

Evaluation of 2 Low-cost High-definition Video Systems for Venous Anastomosis

Background. A literature review of the use of video systems for magnification has suggested that so far, this novel magnification system has only been used to perform arterial anastomoses. The aim of this study was to evaluate the use of 2 low-cost methods of video-assisted magnification in microvascular venous anastomosis in rats. Methods. Thirty rats were randomly divided into 3 matched groups according to the magnification system used: the microscope group, with venous anastomosis performed under a microscope; the camcorder system group, with the procedures performed under a high-definition Handycam HDR-XR160; and the Photographic camera group, for which procedures were performed with an EOS Rebel T3i photographic camera. In both video system groups, a magnification system was connected to a 42-in. television by an HDMI cable. We analyzed weight, venous caliber, total surgery and anastomosis time, patency immediately and 14 days postoperatively, number of stitches, and histological analyses. Results. There were no significant differences between the groups in weight, venous caliber, or number of stitches. Anastomosis under the video systems took longer. Patency rates were similar between the groups, except for the photographic system group that has a lower patency rate at 14 days. The histological analyses were similar in all groups. Conclusion. It is possible to perform a venous anastomosis in rats through video system magnification, with a satisfactory success rate comparable with that for procedures performed under microscopes; however, the kind of video system has a great influence on the final patency.

The Multifactorial Contribution of Publications in Plastic Surgery Journals in Microsurgery Education

BACKGROUND

Microsurgery is one of the most complex operative skills. Recent restrictions on residents' working hours challenge residency program directors to ensure skill acquisition with scant time dedicated to microsurgery practice. We aimed to summarize the contribution of plastic surgery journals in microsurgical education.

METHODS

A comprehensive literature search was performed.

RESULTS

We observed an increasing number of publications on microsurgery education over the years. This could be due to the adoption of new technologies developed in the last 2 decades, the concerns about quality of resident training in the context of reduced work hours, the well-described benefit of medical simulations in other specialties, and the pressure on trainees to be proficient before operating on patients. The variety of aspects addressed in plastic surgery publications is broad: simulators, courses, skills assessment, national surveys, and technology trends.

CONCLUSION

There is an upward trend in the number of publications and plastic surgery journals, demonstrating a remarkable contribution to microsurgery training.

Stereoscopic versus monoscopic displays: Learning fine manual dexterity skills using a microsurgical task simulator

We investigated the learning of fine manual dexterity with a microsurgical instrument and a new simulator in a context of microsurgery. 30 subjects were divided into two groups. One (3D group) interacted with a stereoscopic and the other (2D group) with a monoscopic display. Visual information for the displays was captured from a surgical stereomicroscope. In 20 trials, both groups performed the repetitive tasks of picking up small rods from a funnel-shaped cavity and placing them outside. In analysing learning curves, we found that the initial learning process for hand-eye coordination is easier with a 3D display, and that performance persists at a higher level of proficiency than with the 2D display option. Thus stereoscopic displays can be especially beneficial for novices, for those learning new procedures, or for providing orientation to operators facing a new or altered spatial situation. Simulators with few reliefs or spatial textures should not be used for comparison between 3D and 2D viewing conditions.

Robot-assisted microvascular anastomosis in head and neck free flap reconstruction: Preliminary experiences and results

BACKGROUND

The da Vinci Surgical System has facilitated considerable advancements in surgery. The process and results of robot-assisted microvascular anastomosis in real clinical situations have rarely been reported. This study presents our experience of performing robot-assisted microvascular anastomosis in free flap reconstruction in patients with oropharyngeal cancer.

PATIENTS AND METHODS

This was a retrospective study of reconstructive operations using a free radial forearm flap for oropharyngeal defects after tumor extirpation in 15 consecutive adult patients (12 men and 3 women). In total, 17 robot-assisted microvascular vessel anastomoses (2 arteries and 15 veins) were performed; moreover, 13 arteries and 13 veins were anastomosed using the standard operating microscope and hand-sewing technique.

RESULTS

The recipient and donor vessel diameters were 2.5 ± 0.7 and 2.1 ± 0.8 mm, respectively. The donor blood vessel diameter selected for anastomosis using da Vinci Surgical System was significantly smaller (2.1 ± 0.8 vs. 2.5 ± 0.6 mm) than that for a standard operating microscope and hand-sewing technique (p = .021), the operating time spent (38.4 ± 10.4 vs. 28.0 ± 7.7 min) was significantly longer (p < .001). The vascular patency rate was 100%, and all flaps survived without requiring additional operation for revision.

CONCLUSION

Robotic surgical systems can facilitate vascular microanastomosis and provide a blood vessel patency rate comparable to that of a standard operating microscope and hand-sewing technique.

Microvascular anastomosis under 3D exoscope or endoscope magnification: A proof-of-concept study

Background:

Extracranial–intracranial bypass is a challenging procedure that requires special microsurgical skills and an operative microscope. The exoscope is a tool for neurosurgical visualization that provides view on a heads-up display similar to an endoscope, but positioned external to the operating field, like a microscope. The authors carried out a proof-of-concept study evaluating the feasibility and effectiveness of performing microvascular bypass using various new exoscopic tools.

Methods:

We evaluated microsurgical procedures using a three-dimensional (3D) endoscope, hands-free robotic automated positioning two-dimensional (2D) exoscope, and an ocular-free 3D exoscope, including surgical gauze knot tying, surgical glove cutting, placental vessel anastomoses, and rat vessel anastomoses. Image quality, effectiveness, and feasibility of each technique were compared among different visualization tools and to a standard operative microscope.

Results:

3D endoscopy produced relatively unsatisfactory resolution imaging. It was shown to be sufficient for knot tying and anastomosis of a placental artery, but was not suitable for anastomosis in rats. The 2D exoscope provided higher resolution imaging, but was not adequate for all maneuvers because of lack of depth perception. The 3D exoscope was shown to be functional to complete all maneuvers because of its depth perception and higher resolution.

Conclusion:

Depth perception and high resolution at highest magnification are required for microvascular bypass procedures. Execution of standard microanastomosis techniques was unsuccessful using 2D imaging modalities because of depth-perception-related constraints. Microvascular anastomosis is feasible under 3D exoscopic visualization; however, at highest magnification, the depth perception is inferior to that provided by a standard operative microscope, which impedes the procedure.

Cooperative robot assistant for vitreoretinal microsurgery: development of the RVRMS and feasibility studies in an animal model

PURPOSE

The purpose of the study was to describe the development of a robotic aided surgical system named RVRMS (robotic vitreous retinal microsurgery system) and to evaluate the capability for using it to perform vitreoretinal surgery.

METHODS

The RVRMS was designed and built to include the key components of two independent arms. End-effectors of each arm fix various surgical instruments and perform intraocular manipulation. To evaluate properly the RVRMS, robot-assisted 23-gauge surgical tasks including endolaser for retinal photocoagulation, pars plana vitrectomy (PPV), retinal foreign body removal and retinal vascular cannulation were performed in two different sizes of an animal model. Endolaser was performed in the eye of a living Irish rabbit and the other tasks were done in a harvested porcine eye. For each evaluation, the duration and the successful completion of the task was assessed.

RESULTS

Robot-assisted vitreoretinal operations were successfully performed in nine rabbit eyes and 25 porcine eyes without any iatrogenic complication such as retinal tear or retinal detachment. In the task of using an endolaser, three rows of burns around the induced retinal hole were performed in nine rabbit eyes with half size intervals of laser spots. Nine procine eyes underwent PPV followed by successful posterior vitreous detachment (PVD) induction assisted with triamcinolone acetonide (TA). Nine porcine eyes completed removal of a fine stainless steel wire, which was inserted into prepared retinal tissue. Finally, retinal vascular cannulation with a piece of stainless steel wire (6mm length, 45 μm pipe diameter and one end cut to ∼30° slope) was successfully achieved in seven porcine eyes. The average duration of each procedure was 10.91±1.22 min, 11.68±2.11min, 5.90±0.46 min and 13.5±6.2 min, respectively.

CONCLUSIONS

Maneuverability, accuracy and stability of robot-assisted vitreoretinal microsurgery using the RVRMS were demonstrated in this study. Wider application research of robotic surgery and improvement of a robotic system should be continued.