On the suitability of Thiel cadavers for natural orifice transluminal endoscopic surgery (NOTES): surgical training, feasibility studies, and anatomical education

Measurement of extraction forces of non-absorbable suture and different anchoring systems used for pelvic organ prolapse surgery using soft-embalmed cadavers: A feasibility study

OBJECTIVE

Success of pelvic organ prolapse (POP) mesh procedures also depends on reliable anchoring systems (AS). Our primary aim was to assess the use of soft-embalmed cadavers in testing of different AS and our secondary aim was to compare extraction forces (EF) of different AS and non-absorbable suture (NAS).

STUDY DESIGN

IRB approval was obtained. NAS (Ti-cron®) and different AS were attached to force-measuring instrument (Dynamometer SS25LA) and anchored to anterior longitudinal (ALL) and pectineal ligament (PL) (Protack®, Uplift®, NAS), and sacrospinous ligament (SSL) (Surelift®, Elevate PC®, NAS) of Thiel soft-embalmed cadavers. EF were measured 2-4 times in each cadaver. Data were compared using non-parametric tests. Statistical significance was set at p < 0.05.

RESULTS

Three female cadavers (age 59, 77 and 87) were used. NAS EF were significantly higher than AS EF for ALL and SSL, but not PL. Thiel soft-embalmed cadavers proved to be useful in testing of different AS.

CONCLUSIONS

Use of soft-embalmed cadavers in testing of different AS is feasible. According to our results, the NAS provides most reliable intra-corporeal fixation. However, significant inter- and intra-subject variability indicates that results may also be dependent on the tissue properties and anchoring procedure. Further testing using soft-embalmed cadavers could help optimise mesh procedures and establish a threshold EF necessary for reliable fixation.

Current and potential use of fresh frozen cadaver in surgical training and anatomical education

As surgical procedures continue to be more complex, the need for more effective training in anatomy has increased. The study of anatomy plays a significant role in the understanding of the human body as well as in basic and advanced clinical training. Among the different cadaver models, fresh frozen cadavers (FFCs) are known for their realistic tissue quality. The purpose of this article was to review and summarize the preparation procedures for and reported cases involving FFCs. PubMed, Scopus, Medline, and Web of Science were searched for relevant studies. The preparation procedures were divided into five steps: washing, irrigation, freezing, defrosting, and arterial infusion. Not all steps were reported to be mandatory, but omitting one or more could result in a loss of quality. FFCs were reported to be used for various purposes: undergraduate education, general surgery training, vascular surgery training, minimal access surgery (laparoscopic surgery) training, and microsurgery training. In all categories, expert opinions and statistical analyses indicated successful outcomes. The reasons for high satisfaction with FFCs included realistic texture, capability of reenacting actual operations, and accuracy of anatomical locations. The results also revealed the importance and advantages of the dissection courses in surgical training. Since the direct comparison between cadaver models is insufficient, future studies regarding this topic are deemed necessary. In addition, it would be advantageous to develop methods to improve FFC quality, or ideas to optimize this model for certain purposes.

Modified Larssen solution (MLS)-fixed cadaver model for transoral endoscopic thyroidectomy vestibular approach (TOETVA) education: a feasibility study

BACKGROUND

Training formats for transoral endoscopic thyroidectomy vestibular approach (TOETVA) are limited. Our aim was to create and investigate a TOETVA training model for general and ENT surgeons.

METHODS

A total of 15 modified Larssen solution (MLS) human cadavers were used in the study. A day duration TOETVA human cadaver workshops were offered in two years consecutive. Post-training verbal and online questionnaires were applied to all trainers to evaluate course structure and program, organoleptic characteristics of MLS-fixed human cadavers, and TOETVA training effectiveness. Cost assessment is included in the study.

RESULTS

Ninety-eight participants, i.e., 14 trainers and 84 hands-on (HO) and observer (OB) trainees, attended the workshops, completed the tasks assigned, and fulfilled the questionnaires. Implementation of all steps of TOETVA was approved positively by 89.8% of all participants, 94.4% of HO, and 83.3% of OB trainees. Regarding human cadaver and teaching quality, 10.8 ± 0.8 (10-12) human cadavers were "practical" by 13.2 (94.5%) of the trainers, and by 33.3 (92.5%) of the trainees for all steps of TOETVA. The cadavers were stored for 4.53 years and used 6.27 times repeatedly for endoscopic workshops and research studies. TOETVA workshop cost with repeatable use of MLS-fixed human cadaver is half of other performed TOETVA workshops.

CONCLUSIONS

A TOETVA human cadaver workshop model has not been reported yet. Our findings suggest the feasibility of MLS-fixed human cadaver model for training of TOETVA, preserve the organoleptic properties necessary for the implementation of surgical steps, and reduce the cost.

Meniscus regeneration by 3D printing technologies: Current advances and future perspectives

Meniscal tears are a frequent orthopedic injury commonly managed by conservative strategies to avoid osteoarthritis development descending from altered biomechanics. Among cutting-edge approaches in tissue engineering, 3D printing technologies are extremely promising guaranteeing for complex biomimetic architectures mimicking native tissues. Considering the anisotropic characteristics of the menisci, and the ability of printing over structural control, it descends the intriguing potential of such vanguard techniques to meet individual joints’ requirements within personalized medicine. This literature review provides a state-of-the-art on 3D printing for meniscus reconstruction. Experiences in printing materials/technologies, scaffold types, augmentation strategies, cellular conditioning have been compared/discussed; outcomes of pre-clinical studies allowed for further considerations. To date, translation to clinic of 3D printed meniscal devices is still a challenge: meniscus reconstruction is once again clear expression of how the integration of different expertise (e.g., anatomy, engineering, biomaterials science, cell biology, and medicine) is required to successfully address native tissues complexities.

Forensic Implications of Anatomical Education and Surgical Training With Cadavers

Anatomical education and surgical training with cadavers are usually considered an appropriate method of teaching, above all for all surgeons at various levels. Indeed, in such a way they put into practice and exercise a procedure before performing it live, reducing the learning curve in a safe environment and the risks for the patients. Really, up to now it is not clear if the nonuse of the cadavers for anatomical education and surgical training can have also forensic implications. A substantial literature research was used for this review, based on PubMed and Web of Science database. From this review, it is clear that the cadaveric training could be considered mandatory, both for surgeons and for medical students, leading to a series of questions with forensic implications. Indeed, there are many evidences that a cadaver lab can improve the learning curve of a surgeon, above all in the first part of the curve, in which frequent and severe complications are possible. Consequently, a medical responsibility for residents and surgeons which perform a procedure without adequate training could be advised, but also for hospital, that has to guarantee a sufficient training for its surgeons and other specialists through cadaver labs. Surely, this type of training could help to improve the practical skills of surgeons working in small hospitals, where some procedures are rare. Cadaver studies can permit a better evaluation of safety and efficacy of new surgical devices by surgeons, avoiding using patients as ≪guinea pigs≫. Indeed, a legal responsibility for a surgeon and other specialists could exist in the use of a new device without an apparent regulatory oversight. For a good medical practice, the surgeons should communicate to the patient the unsure procedural risks, making sure the patients' full understanding about the novelty of the procedure and that they have used this technique on few, if any, patients before. Cadaver training could represent a shortcut in the standard training process, increasing both the surgeon learning curve and patient confidence. Forensic clinical anatomy can supervise and support all these aspects of the formation and of the use of cadaver training.

Training Simulators for Gastrointestinal Endoscopy: Current and Future Perspectives

Simple Summary

Over the last decades, visual endoscopy has become a gold standard for the detection and treatment of gastrointestinal cancers. However, mastering endoscopic procedures is complex and requires long hours of practice. In this context, simulation-based training represents a valuable opportunity for acquiring technical and cognitive skills, suiting the different trainees’ learning pace and limiting the risks for the patients. In this regard, the present contribution aims to present a critical and comprehensive review of the current technology for gastrointestinal (GI) endoscopy training, including both commercial products and platforms at a research stage. Not limited to it, the recent revolution played by the technological advancements in the fields of robotics, artificial intelligence, virtual/augmented reality, and computational tools on simulation-based learning is documented and discussed. Finally, considerations on the future trend of this application field are drawn, highlighting the impact of the most recent pandemic and the current demographic trends.

Abstract

Gastrointestinal (GI) endoscopy is the gold standard in the detection and treatment of early and advanced GI cancers. However, conventional endoscopic techniques are technically demanding and require visual-spatial skills and significant hands-on experience. GI endoscopy simulators represent a valid solution to allow doctors to practice in a pre-clinical scenario. From the first endoscopy mannequin, developed in 1969, several simulation platforms have been developed, ranging from purely mechanical systems to more complex mechatronic devices and animal-based models. Considering the recent advancement of technologies (e.g., artificial intelligence, augmented reality, robotics), simulation platforms can now reach high levels of realism, representing a valid and smart alternative to standard trainee/mentor learning programs. This is particularly true nowadays, when the current demographic trend and the most recent pandemic demand, more than ever, the ability to cope with many patients. This review offers a broad view of the technology available for GI endoscopy training, including platforms currently in the market and the relevant advancements in this research and application field. Additionally, new training needs and new emerging technologies are discussed to understand where medical education is heading.

Educational training in laparoscopic gynecological surgery based on ethanol-glycerol-lysoformin-preserved body donors

PURPOSE

Educational training of laparoscopic skills performed on body donors is considered the gold standard prior to surgery in living patients. Appropriate, safe, and feasible fixation of body donors, reflecting true-to-life conditions of tissues, is an essential prerequisite for training workshops.

MATERIALS AND METHODS

Here we describe and evaluate a modified ethanol-glycerol-lysoformin-based fixation technique. Body donors were fixed by perfusion (70% ethanol, 30% glycerol, 0.3% lysoformin; ca. 20l) via femoral artery and stored in a humid atmosphere (1% thymol) at 4°C. Technical equipment included a mobile operating table, endoscopy system with gas insufflation, suction/irrigation pump, standard and electrosurgical instruments. The tissue properties of ethanol-glycerol-lysoformin-fixed body donors and their suitability for laparoscopic surgery were tested and compared to the in vivo situation.

RESULTS

Modified ethanol-glycerol-lysoformin fixation was a simple, cost-efficient and hazard-free procedure, resulting in near-to-life tissue conditions regarding consistency and flexibility, with moderate discoloration and greater viscosity of organs. Key laparoscopic procedures (trocar handling, pneumoperitoneum, blunt/sharp dissection, partial/total removal of organs, bi- or monopolar electrosurgery, suturing techniques) could be performed without difficulty. Multiple reuse of body donors was feasible over one year. Compared to the in vivo situation, the investigation of body donors required a greater degree of gas insufflation and more energy for electrosurgery.

CONCLUSIONS

Modified ethanol-glycerol-lysoformin fixation applied to body donors permitted laparoscopic surgery in a realistic and practical manner. Due to its logistic advantages, this technique provides appropriate conditions to train laparoscopic skills and implement novel minimally invasive approaches.

A Survey on the Knowledge and Attitudes of Italian Medical Students toward Body Donation: Ethical and Scientific Considerations

Post mortem body donation (PMBD) for medical training and research plays a key role in medical-surgical education. The aim of this study is to evaluate Italian medical students’ awareness and attitudes regarding this practice. A questionnaire was sent to 1781 Italian medical students (MS). A total of 472 MS responded: 406 (92.91%) had a strongly positive attitude to PMBD, while 31 (7.09%) were not in favor. The majority of subjects were Catholic (56.36%), while 185 and 21 subjects, said that they did not hold any religious beliefs, or were of other religions, respectively. Multivariate analysis showed significant associations (p-values < 0.05) between PMBD and religion, as well as perceptions of PMBD as an act of altruism, a tool for learning surgical practices, body mutilation, and an act contrary to faith. Although Italian MS believed cadaver dissection to be an important part of their education, they did not know much about it and had not received training on this altruistic choice. As future doctors, MS can play an important role in raising public awareness of the importance of PMBD for medical education and research. Specific educational programs to improve knowledge of this topic among MS are needed.

Human cadavers to evaluate prototypes of minimally invasive surgical instruments: A feasibility study

BACKGROUND

New technology should be extensively tested before it is tried on patients. Unfortunately representative models are lacking. In theory, fresh frozen human cadavers are excellent models.

OBJECTIVE

To identify strengths and weaknesses of fresh frozen human cadavers as research models for new technology prior to implementation in gynecological surgery.

METHODS

During pre-clinical validation studies regarding the MobiSep uterine manipulator, test procedures were performed on fresh frozen cadavers. Both the experimental setup as the performance of the prototype were assessed.

RESULTS

Five tests including six human cadavers were performed. Major changes were made to the MobiSep prototype design. The cadavers of two tests closely resembled surgical experiences as found in live patients. The anatomy of 4 of the 6 cadavers was not fully representative due to atrophy of the internal genitalia caused by age and due to the presence of pathology such extensive tumorous tissue.

CONCLUSION

The cadaver tests provided vital information regarding design and functionality, that failed to emerge during the in-vitro testing. However, experiments are subject to anatomical uncertainties or restrictions. Consequently, the suitability of a cadaver should be carefully assessed before it is used for testing new technology.

Cadaveric simulation: a review of reviews

BACKGROUND

Traditional surgical training, largely based on the Halstedian model "see one, do one, teach one" is not as effective in the era of working time restrictions and elaborate shift-patterns. As a result, contemporary surgeons turned to educational methods outside the operating theatre such as simulation. Cadavers are high fidelity models but their use has ethical and cost implications and their availability may be limited. In this review, we explore the role of cadaveric simulation in modern surgical education.

METHODS

All the Evidence-Based Medicine databases were searched for relevant reviews. The resulting studies were assessed for inclusion to this review, according to pre-determined criteria. Data extraction was performed using a custom-made spreadsheet, and the quality of included reviews was assessed using a validated scoring system (AMSTAR).

RESULTS

The literature review yielded 33 systematic reviews; five of which matched the inclusion criteria and were included in this review of reviews. Cadaveric simulation was found to have good face (subjective assessment of usefulness) and content validity (whether a specific element adds or retracts to the educational value) while trainees improved their surgical skills after practicing on cadavers. However, concerns have been raised about ethical issues, high cost and availability.

CONCLUSION

Cadavers are an effective medium for surgical teaching, and it may be appropriate for them to be used whenever surrounding conditions such cost and availability allow. Further research is required to provide evidence on whether there is equivalence between cadavers and other educational media which may not bear the same shortcomings.

Forensic clinical anatomy: A new field of study with application to medicolegal issues

Forensic clinical anatomy is a new practical application of the discipline of Clinical Anatomy for ascertaining and evaluating medicolegal questions. In particular, individual anatomy (normal anatomy, anatomical variations, age-, disease-, or surgery-related modifications) can acquire significant relevance in various fields of legal medicine such as child abuse, sudden death, medical responsibility and/or liability, personal injury and damage. Anatomical data of forensic interest frequently arise from the correct application of methods of ascertainment; anatomical methods may then be required for further comprehensive analysis. The rigorous interpretation of anatomical data, derived from the ascertainment phase and analyzed on the basis of pertinent literature, can be pivotal for the correct application of evaluation criteria in various forensic contexts. Clin. Anat. 30:2-5, 2017. © 2016 Wiley Periodicals, Inc.

A brief history of topographical anatomy

This brief history of topographical anatomy begins with Egyptian medical papyri and the works known collectively as the Greco-Arabian canon, the time line then moves on to the excitement of discovery that characterised the Renaissance, the increasing regulatory and legislative frameworks introduced in the 18th and 19th centuries, and ends with a consideration of the impact of technology that epitomises the period from the late 19th century to the present day. This paper is based on a lecture I gave at the Winter Meeting of the Anatomical Society in Cambridge in December 2015, when I was awarded the Anatomical Society Medal.

Cadaveric Spinal Surgery Simulation: A Comparison of Cadaver Types

Study Design Single-blinded study. Objective To assess the suitability of three types of cadaver for simulating pedicle screw insertion and establish if there is an ideal. Methods Three types of cadaver-Thiel-embalmed, Crosado-embalmed, and formaldehyde-embalmed-were draped and the spines exposed. Experienced surgeons were asked to place pedicle screws in each cadaver and give written questionnaire feedback using a modified Likert scale. Soft tissue and bony properties were assessed, along with the role of simulation in spinal surgery training. Results The Thiel cadaver rated highest for soft tissue feel and appearance with a median score of 6 for both (range 2 to 7). The Crosado cadaver rated highest for bony feel, with a median score of 6 (range 2 to 7). The formaldehyde cadaver rated lowest for all categories with median scores of 2, 2.5, and 3.5, respectively. All surgeons felt pedicle screw insertion should be learned in a simulated setting using human cadavers. Conclusion Thiel and Crosado cadavers both offered lifelike simulation of pedicle screw insertion, with each having advantages depending on whether the focus is on soft tissue approach or technical aspects of bony screw insertion. Both cadaver types offer the advantage of long life span, unlike fresh frozen tissue, which means cadavers can be used multiple times, thus reducing the costs.