EASIER: A new model for online learning of minimally invasive surgery skills.

INTRODUCTION: Technology Enhanced Learning (TEL) can provide the tools to safely master minimally invasive surgery (MIS) skills in patient-free environments and receive immediate objective feedback without the constant presence of an instructor. However, TEL-based systems tend to work isolated from one another, focus on different skills, and fail to provide contents without a sound pedagogical background. OBJECTIVE: The objective of this descriptive study is to present in detail EASIER, an innovative TEL platform for surgical and interventional training, as well as the results of its validation. METHODS: EASIER provides a Learning Management System (LMS) for institutions and content creators that can connect and integrate TEL "external assets" (virtual reality simulators, augmented box trainers, augmented videos, etc.) addressing different skills. The platform integrates all skills under an Assessment Module that measures skills' progress in different courses. Finally, it provides content creators with a pedagogical model to scaffold contents while retaining flexibility to approach course design with different training philosophies in mind. Three courses were developed and hosted in the platform to validate it with end-users in terms of usability, performance, learning results in the courses and student self-perception on learning. RESULTS: In total 111 volunteers completed the validation. The study was limited due to the COVID-19 pandemic, which limited access to external assets (virtual reality simulators). Nevertheless, usability was rated with 73.1 in the System Usability Scale. Most positive aspects on performance were easiness to access the platform, easiness to change the configuration and not requiring additional plug-ins to use the platform. The platform was rated above average in the six scales of the User Experience Questionnaire. Overall, student results improved significantly across the three courses (p < 0.05). CONCLUSIONS: This study provides, within its limitations, evidence on the usefulness of the EASIER platform for distance learning of MIS skills. Results show the potential impact of the platform and are an encouraging boost for the future, especially in the aftermath of the COVID-19 pandemic.

Clinical Validation Benchmark Dataset and Expert Performance Baseline for Colorectal Polyp Localization Methods.

Colorectal cancer is one of the leading death causes worldwide, but, fortunately, early detection highly increases survival rates, with the adenoma detection rate being one surrogate marker for colonoscopy quality. Artificial intelligence and deep learning methods have been applied with great success to improve polyp detection and localization and, therefore, the adenoma detection rate. In this regard, a comparison with clinical experts is required to prove the added value of the systems. Nevertheless, there is no standardized comparison in a laboratory setting before their clinical validation. The ClinExpPICCOLO comprises 65 unedited endoscopic images that represent the clinical setting. They include white light imaging and narrow band imaging, with one third of the images containing a lesion but, differently to another public datasets, the lesion does not appear well-centered in the image. Together with the dataset, an expert clinical performance baseline has been established with the performance of 146 gastroenterologists, who were required to locate the lesions in the selected images. Results shows statistically significant differences between experience groups. Expert gastroenterologists' accuracy was 77.74, while sensitivity and specificity were 86.47 and 74.33, respectively. These values can be established as minimum values for a DL method before performing a clinical trial in the hospital setting.

Computational simulation-based comparative analysis of standard 3D printing and conical nozzles for pneumatic and piston-driven bioprinting.

Bioprinting is an application of additive manufacturing that can deliver promising results in regenerative medicine. Hydrogels, as the most used materials in bioprinting, are experimentally analyzed to assure printability and suitability for cell culture. Besides hydrogel features, the inner geometry of the microextrusion head might have an equal impact not only on printability but also on cellular viability. In this regard, standard 3D printing nozzles have been widely studied to reduce inner pressure and get faster printings using highly viscous melted polymers. Computational fluid dynamics is a useful tool capable of simulating and predicting the hydrogel behavior when the extruder inner geometry is modified. Hence, the objective of this work is to comparatively study the performance of a standard 3D printing and conical nozzles in a microextrusion bioprinting process through computational simulation. Three bioprinting parameters, namely pressure, velocity, and shear stress, were calculated using the level-set method, considering a 22G conical tip and a 0.4 mm nozzle. Additionally, two microextrusion models, pneumatic and piston-driven, were simulated using dispensing pressure (15 kPa) and volumetric flow (10 mm3/s) as input, respectively. The results showed that the standard nozzle is suitable for bioprinting procedures. Specifically, the inner geometry of the nozzle increases the flow rate, while reducing the dispensing pressure and maintaining similar shear stress compared to the conical tip commonly used in bioprinting.

Novel Pixelwise Co-Registered Hematoxylin-Eosin and Multiphoton Microscopy Image Dataset for Human Colon Lesion Diagnosis.

Colorectal cancer presents one of the most elevated incidences of cancer worldwide. Colonoscopy relies on histopathology analysis of hematoxylin-eosin (H&E) images of the removed tissue. Novel techniques such as multi-photon microscopy (MPM) show promising results for performing real-time optical biopsies. However, clinicians are not used to this imaging modality and correlation between MPM and H&E information is not clear. The objective of this paper is to describe and make publicly available an extensive dataset of fully co-registered H&E and MPM images that allows the research community to analyze the relationship between MPM and H&E histopathological images and the effect of the semantic gap that prevents clinicians from correctly diagnosing MPM images. The dataset provides a fully scanned tissue images at 10x optical resolution (0.5 µm/px) from 50 samples of lesions obtained by colonoscopies and colectomies. Diagnostics capabilities of TPF and H&E images were compared. Additionally, TPF tiles were virtually stained into H&E images by means of a deep-learning model. A panel of 5 expert pathologists evaluated the different modalities into three classes (healthy, adenoma/hyperplastic, and adenocarcinoma). Results showed that the performance of the pathologists over MPM images was 65% of the H&E performance while the virtual staining method achieved 90%. MPM imaging can provide appropriate information for diagnosing colorectal cancer without the need for H&E staining. However, the existing semantic gap among modalities needs to be corrected.

Can effective pedagogy be ensured in minimally invasive surgery e-learning?

INTRODUCTION: Effectiveness of e-learning diminishes without the support of a pedagogical model to guide its use. In minimally invasive surgery (MIS), this has been reported as a limitation when technology is used to deliver contents without a sound pedagogical background. MATERIAL AND METHODS: We describe how a generic pedagogical model, the 3D pedagogy framework, can be used for setting learning outcomes and activities in e-learning platforms focused on MIS cognitive skills. A demonstrator course on Nissen fundoplication was developed following the model step-by-step in the MISTELA learning platform. Course design was informed by Kolb's Experiential learning model. Content validation was performed by 13 MIS experts. RESULTS: Ten experts agreed on the suitability of content structuring done according to the pedagogical model. All experts agreed that the course provides means to assess the intended learning outcomes. CONCLUSIONS: This work showcases how a general-purpose e-learning framework can be accommodated to the needs of MIS training without limiting the course designers' pedagogical approach. Key advances for its success include: (1) proving the validity of the model in the wider scope of MIS skills and (2) raising awareness amongst stakeholders on the need of developing training plans with explicit, rather than assumed, pedagogical foundations. Abbreviations: MIS: minimally invasive surgery; TEL: technology enhanced learning.

Prognostic factors of clot resolution on follow-up computed tomography angiography and recurrence after a first acute pulmonary embolism.

BACKGROUND: Recent studies seem to confirm the relationship between residual pulmonary obstruction (RPO) in pulmonary embolism (PE) and risk of recurrent thrombosis and chronic thromboembolic pulmonary hypertension (CTEPH). However, the prognostic factors associated with PE resolution on follow-up computed tomography angiography (CTA) are not clear. OBJECTIVES: To determine the prognostic factors of resolution of PE diagnosed and monitored by CTA and the impact of RPO on late complications. METHODS: We retrospectively analyzed 241 patients with PE who had undergone a 12-month follow-up and CT scan evaluation at 6 months. Factors related to resolution and the impact of RPO on the outcome were analyzed. RESULTS: Resolution was achieved in 74.3% of all cases after 6 months of treatment. Absence of chronic obstructive pulmonary disease (COPD) (OR, 3.22 [1.35-7.71]; p = 0.009), provoked PE (OR, 2.02 [1.08-3.79]; p = 0.028), early initiation of treatment (<7 days) (OR, 2.42 [1.22-4.78]; p = 0.011), and degree of obstruction caused by the initial PE as indicated by a Qanadli score lower than 16 (OR, 2.12 [1.03-4.37]; p = 0.043) were associated with complete resolution. RPO was associated with recurrent PE as well as the combined endpoint consisting of recurrent VTE and/or CTEPH (4.67 [95% CI, 1.26-17.26]; p = 0.02) and (OR 6.4 [95% CI, 1.9-21.2]; p < 0.005), respectively. CONCLUSIONS: Resolution of PE is associated with a lower risk of recurrent thrombosis. Earlier initiation of treatment improves prognosis as measured by resolution on follow-up CTA.

Medical needs related to the endoscopic technology and colonoscopy for colorectal cancer diagnosis.

BACKGROUND: The high incidence and mortality rate of colorectal cancer require new technologies to improve its early diagnosis. This study aims at extracting the medical needs related to the endoscopic technology and the colonoscopy procedure currently used for colorectal cancer diagnosis, essential for designing these demanded technologies. METHODS: Semi-structured interviews and an online survey were used. RESULTS: Six endoscopists were interviewed and 103 were surveyed, obtaining the demanded needs that can be divided into: a) clinical needs, for better polyp detection and classification (especially flat polyps), location, size, margins and penetration depth; b) computer-aided diagnosis (CAD) system needs, for additional visual information supporting polyp characterization and diagnosis; and c) operational/physical needs, related to limitations of image quality, colon lighting, flexibility of the endoscope tip, and even poor bowel preparation. CONCLUSIONS: This study shows some undertaken initiatives to meet the detected medical needs and challenges to be solved. The great potential of advanced optical technologies suggests their use for a better polyp detection and classification since they provide additional functional and structural information than the currently used image enhancement technologies. The inspection of remaining tissue of diminutive polyps (< 5 mm) should be addressed to reduce recurrence rates. Few progresses have been made in estimating the infiltration depth. Detection and classification methods should be combined into one CAD system, providing visual aids over polyps for detection and displaying a Kudo-based diagnosis suggestion to assist the endoscopist on real-time decision making. Estimated size and location of polyps should also be provided. Endoscopes with 360° vision are still a challenge not met by the mechanical and optical systems developed to improve the colon inspection. Patients and healthcare providers should be trained to improve the patient's bowel preparation.

A significant decrease in D-dimer concentration within one month of anticoagulation therapy as a predictor of both complete recanalization and risk of recurrence after initial pulmonary embolism.

BACKGROUND: Abnormal D-dimer concentration measured during anticoagulation therapy (AT) or within one month of discontinuation, is associated with residual pulmonary obstruction (RPO) and risk of recurrent venous thromboembolism (VTE) after a first episode of pulmonary embolism (PE). We hypothesized that a significant decrease in D-dimer concentration within the first month of AT in patients with a first episode of PE may predict complete recanalization and a lower risk of recurrent VTE. METHODS: One hundred and fifty patients with PE received anticoagulation therapy for three or six months when control computed tomography angiography (CTA) was performed. D-dimer levels were measured at admission and at 1-, 3- and/or 6-month follow-ups after the initial event. Clinical, echocardiographic, CTA and analytical data were collected. Predictive factors of RPO and predictive ability of D-dimer concentration at 1- and 6-month follow-ups were evaluated. RESULTS: Of the 150 eligible patients, 33 (22%) had RPO in control CTA. Idiopathic PE, a delay of >7 days between symptom onset and diagnosis, and clinical PE severity determined by a s-PESI score ≥ 1 were associated with RPO. D-dimer concentration within a month of AT was significantly higher (823 [558-1259] vs 436 [243-934] ng/ml; p = 0.019) in patients with RPO; decrease (445 [35-1899] vs 912 [476-2858] ng/ml; p = 0.047) and decrease percentage (31.4% vs 76.6%; p < 0.005) in D-dimer concentrations were significantly lower. ROC analysis showed that decrease percentage in D-dimer concentration identified patients with complete recanalization (AUC 0.715, [95% CI, 0.611-0.819], p < 0.005). Decreases of >70% in initial D-dimer at 1-month (OR, 0.56, [95% CI, 0.45-0.70] p = 0.037) and 6-month follow-ups (OR, 0.31 [CI 95%, 0.15-0.66], p = 0.03) were associated with a lower risk of recurrent PE. CONCLUSION: A significant decrease in D-dimer concentration within the first month of AT is associated with complete recanalization and could predict a lower risk of recurrent thrombosis after a first episode of PE.

Deep learning to find colorectal polyps in colonoscopy: A systematic literature review.

Colorectal cancer has a great incidence rate worldwide, but its early detection significantly increases the survival rate. Colonoscopy is the gold standard procedure for diagnosis and removal of colorectal lesions with potential to evolve into cancer and computer-aided detection systems can help gastroenterologists to increase the adenoma detection rate, one of the main indicators for colonoscopy quality and predictor for colorectal cancer prevention. The recent success of deep learning approaches in computer vision has also reached this field and has boosted the number of proposed methods for polyp detection, localization and segmentation. Through a systematic search, 35 works have been retrieved. The current systematic review provides an analysis of these methods, stating advantages and disadvantages for the different categories used; comments seven publicly available datasets of colonoscopy images; analyses the metrics used for reporting and identifies future challenges and recommendations. Convolutional neural networks are the most used architecture together with an important presence of data augmentation strategies, mainly based on image transformations and the use of patches. End-to-end methods are preferred over hybrid methods, with a rising tendency. As for detection and localization tasks, the most used metric for reporting is the recall, while Intersection over Union is highly used in segmentation. One of the major concerns is the difficulty for a fair comparison and reproducibility of methods. Even despite the organization of challenges, there is still a need for a common validation framework based on a large, annotated and publicly available database, which also includes the most convenient metrics to report results. Finally, it is also important to highlight that efforts should be focused in the future on proving the clinical value of the deep learning based methods, by increasing the adenoma detection rate.

Unravelling the effect of data augmentation transformations in polyp segmentation.

PURPOSE: Data augmentation is a common technique to overcome the lack of large annotated databases, a usual situation when applying deep learning to medical imaging problems. Nevertheless, there is no consensus on which transformations to apply for a particular field. This work aims at identifying the effect of different transformations on polyp segmentation using deep learning. METHODS: A set of transformations and ranges have been selected, considering image-based (width and height shift, rotation, shear, zooming, horizontal and vertical flip and elastic deformation), pixel-based (changes in brightness and contrast) and application-based (specular lights and blurry frames) transformations. A model has been trained under the same conditions without data augmentation transformations (baseline) and for each of the transformation and ranges, using CVC-EndoSceneStill and Kvasir-SEG, independently. Statistical analysis is performed to compare the baseline performance against results of each range of each transformation on the same test set for each dataset. RESULTS: This basic method identifies the most adequate transformations for each dataset. For CVC-EndoSceneStill, changes in brightness and contrast significantly improve the model performance. On the contrary, Kvasir-SEG benefits to a greater extent from the image-based transformations, especially rotation and shear. Augmentation with synthetic specular lights also improves the performance. CONCLUSION: Despite being infrequently used, pixel-based transformations show a great potential to improve polyp segmentation in CVC-EndoSceneStill. On the other hand, image-based transformations are more suitable for Kvasir-SEG. Problem-based transformations behave similarly in both datasets. Polyp area, brightness and contrast of the dataset have an influence on these differences.

[Validity studies in laparoscopic simulation. Methodology and design considerations.] / Validación en simulación laparoscópica. Consideraciones metodológicas y de diseño.

OBJECTIVES: To describe a roadmap of the most representative milestones and considerations in the validation of surgical simulators, especially those of laparoscopic surgery. And additionally, help determine when in this process a simulator can be considered as validated. METHODS: A non-systematic review was carried out searching terms like simulation, validation, training, assessment, skills and learning curve, as well as providing the experience accumulated by our center. RESULTS: An ideal classical validation process should consist of the following steps: fidelity, verification/calibration/ reliability, subjective and objective strategies. Baseline tests of fidelity and verification/calibration/ technological reliability are not always detailed in the simulation literature. A simulator can be considered validated if, at least, satisfactorily completed any of the two main objective strategies, that is, constructive and/or criterion validity. CONCLUSIONS: The methodologies to validate simulators as useful and reliable for the improvement of psychomotor/ technical skills are widely analyzed, although there is a variety of approaches depending on the scientific reference consulted, not being implemented equally in all works. This apparent arbitrariness should be considered in advance because it can lead the researcher to misunderstandings, especially when the simulator will be regarded as valid.

OBJETIVOS: Describir una hoja de ruta de los hitos y consideraciones más representativos en la validación de simuladores quirúrgicos, especialmente los de cirugía laparoscópica. Y adicionalmente contribuir a determinar en qué momento de este proceso puede considerarse un simulador como validado.MÉTODOS: Se realizó una revisión no sistemática con los términos simulación, validación, formación, entrenamiento, evaluación, habilidades y curva de aprendizaje, además de aportar la experiencia acumulada por nuestro centro. RESULTADOS: Un proceso ideal clásico de validación debería constar de los siguientes pasos: Fidelidad, Verificación/ Calibración/Fiabilidad, estrategias subjetivas y objetivas. Las pruebas de inicio tanto de Fidelidad como de Verificación/Calibración/Fiabilidad tecnológica no siempre están descritas de manera explícita en los trabajos de validación de simuladores. Un simulador puede considerarse validado si al menos ha completado satisfactoriamente una validación de cualquiera de los dos grandes bloques de tipo objetivo, es decir, constructiva y/o de criterio. CONCLUSIONES: Los métodos que permiten validar simuladores como útiles y fiables para la mejora de habilidades de tipo psicomotor/técnico están ampliamente documentados aunque existe cierta variedad de enfoques en función de la referencia científica que se consulte, no aplicándose por igual en todos los trabajos. Esta aparente arbitrariedad debería ser conocida de antemano porque puede llevar al investigador a ciertos equívocos, especialmente a la hora de afirmar cuándo el simulador se considera plenamente validado.

Validación en simulación laparoscópica. Consideraciones metodológicas y de diseño / Validity studies in laparoscopic simulation. Methodology and design considerations

Objetivos: Describir una hoja de ruta de los hitos y consideraciones más representativos en la validación de simuladores quirúrgicos, especialmente los de cirugía laparoscópica. Y adicionalmente contribuir a determinar en qué momento de este proceso puede considerarse un simulador como validado. Métodos: Se realizó una revisión no sistemática con los términos simulación, validación, formación, entrenamiento, evaluación, habilidades y curva de aprendizaje, además de aportar la experiencia acumulada por nuestro centro. Resultados: Un proceso ideal clásico de validación debería constar de los siguientes pasos: Fidelidad, Verificación/ Calibración/Fiabilidad, estrategias subjetivas y objetivas. Las pruebas de inicio tanto de Fidelidad como de Verificación/Calibración/Fiabilidad tecnológica no siempre están descritas de manera explícita en los trabajos de validación de simuladores. Un simulador puede considerarse validado si al menos ha completado satisfactoriamente una validación de cualquiera de los dos grandes bloques de tipo objetivo, es decir, constructiva y/o de criterio. Conclusiones: Los métodos que permiten validar simuladores como útiles y fiables para la mejora de habilidades de tipo psicomotor/técnico están ampliamente documentados aunque existe cierta variedad de enfoques en función de la referencia científica que se consulte, no aplicándose por igual en todos los trabajos. Esta aparente arbitrariedad debería ser conocida de antemano porque puede llevar al investigador a ciertos equívocos, especialmente a la hora de afirmar cuándo el simulador se considera plenamente validado

Objectives: To describe a roadmap of the most representative milestones and considerations in the validation of surgical simulators, especially those of laparoscopic surgery. And additionally, help determine when in this process a simulator can be considered as validated. Methods: A non-systematic review was carried out searching terms like simulation, validation, training, assessment, skills and learning curve, as well as providing the experience accumulated by our center. Results: An ideal classical validation process should consist of the following steps: fidelity, verification/calibration/ reliability, subjective and objective strategies. Baseline tests of fidelity and verification/calibration/ technological reliability are not always detailed in the simulation literature. A simulator can be considered validated if, at least, satisfactorily completed any of the two main objective strategies, that is, constructive and/or criterion validity. Conclusions: The methodologies to validate simulators as useful and reliable for the improvement of psychomotor/ technical skills are widely analyzed, although there is a variety of approaches depending on the scientific reference consulted, not being implemented equally in all works. This apparent arbitrariness should be considered in advance because it can lead the researcher to misunderstandings, especially when the simulator will be regarded as valid

Validation of the three web quality dimensions of a minimally invasive surgery e-learning platform.

INTRODUCTION: E-learning web environments, including the new TELMA platform, are increasingly being used to provide cognitive training in minimally invasive surgery (MIS) to surgeons. A complete validation of this MIS e-learning platform has been performed to determine whether it complies with the three web quality dimensions: usability, content and functionality. METHODS: 21 Surgeons participated in the validation trials. They performed a set of tasks in the TELMA platform, where an e-MIS validity approach was followed. Subjective (questionnaires and checklists) and objective (web analytics) metrics were analysed to achieve the complete validation of usability, content and functionality. RESULTS: The TELMA platform allowed access to didactic content with easy and intuitive navigation. Surgeons performed all tasks with a close-to-ideal number of clicks and amount of time. They considered the design of the website to be consistent (95.24%), organised (90.48%) and attractive (85.71%). Moreover, they gave the content a high score (4.06 out of 5) and considered it adequate for teaching purposes. The surgeons scored the professional language and content (4.35), logo (4.24) and recommendations (4.20) the highest. Regarding functionality, the TELMA platform received an acceptance of 95.24% for navigation and 90.48% for interactivity. CONCLUSIONS: According to the study, it seems that TELMA had an attractive design, innovative content and interactive navigation, which are three key features of an e-learning platform. TELMA successfully met the three criteria necessary for consideration as a website of quality by achieving more than 70% of agreements regarding all usability, content and functionality items validated; this constitutes a preliminary requirement for an effective e-learning platform. However, the content completeness, authoring tool and registration process required improvement. Finally, the e-MIS validity methodology used to measure the three dimensions of web quality in this work can be applied to other clinical areas or training fields.

Approaches towards training in human risk management of surgical technology.

A safe application of modern surgical technology and computer-assisted surgery devices is based on an operation by adequately trained surgeons who are familiar with the benefits and limitations of the devices. We analyzed the in-depth interviews with seven Spanish and 10 German surgeons. Together with other studies, this analysis highlights the need for specific training in technological competence for surgeons. One way to train technological competence is to help surgeons understanding the basic principles of medical devices as well as explaining the basic concepts of risk analysis and risk management. Based on this premise, a stage model for risk assessment was developed and adapted for the training of surgeons. This was developed further into a train the trainer (TTT) concept, which was then evaluated for two example cases. During TTT-training, the trainers (expert surgeons) performed a risk analysis for several medical devices. Afterwards, the trainers organized a surgical workshop for surgical trainees (resident surgeons), in which high-fidelity simulators and the original medical devices were used. The results showed that the surgeons performed the risk analysis correctly with the stage model and afterwards were able to successfully apply the results in the workshop context.

TELMA: Technology-enhanced learning environment for minimally invasive surgery.

BACKGROUND: Cognitive skills training for minimally invasive surgery has traditionally relied upon diverse tools, such as seminars or lectures. Web technologies for e-learning have been adopted to provide ubiquitous training and serve as structured repositories for the vast amount of laparoscopic video sources available. However, these technologies fail to offer such features as formative and summative evaluation, guided learning, or collaborative interaction between users. METHODOLOGY: The "TELMA" environment is presented as a new technology-enhanced learning platform that increases the user's experience using a four-pillared architecture: (1) an authoring tool for the creation of didactic contents; (2) a learning content and knowledge management system that incorporates a modular and scalable system to capture, catalogue, search, and retrieve multimedia content; (3) an evaluation module that provides learning feedback to users; and (4) a professional network for collaborative learning between users. Face validation of the environment and the authoring tool are presented. RESULTS: Face validation of TELMA reveals the positive perception of surgeons regarding the implementation of TELMA and their willingness to use it as a cognitive skills training tool. Preliminary validation data also reflect the importance of providing an easy-to-use, functional authoring tool to create didactic content. CONCLUSION: The TELMA environment is currently installed and used at the Jesús Usón Minimally Invasive Surgery Centre and several other Spanish hospitals. Face validation results ascertain the acceptance and usefulness of this new minimally invasive surgery training environment.

[New technologies in minimally invasive surgery training: what do surgeons demand?]. / Nuevas tecnologías en formación de cirugía de mínima invasión: ¿qué demandan los cirujanos?

BACKGROUND: Minimally invasive surgery might greatly benefit from the Information and Communications Technologies. The objective of this work is to determine the better approach to include those technologies, in particular an e-Learning platform, into an in-person training course. METHODS: An online survey was sent to all participants in any of the laparoscopic training courses at Jesús Usón Minimally Invasive Surgery Centre. This survey included questions regarding new technologies used for training. Once all data were gathered, a descriptive analysis was performed. RESULTS: 382 questionnaires were sent of which 102 were correctly received back. This means a response rate equal to 30%. Current theoretical training means are watching surgical videos (85-83.3%) and assisting to in-person training courses (77-75.5%). Participants rated as useful the use of new technologies for training (4.1 ± 0.9) and they would mainly use it both before and after assisting to an in-person training course (80-78.4%). CONCLUSIONS: It is proposed a methodology that provides participants with didactic resources based on surgical videos, both before and after assisting to an in-person training course. Through the application of this methodology, an improvement and reduction of the time that surgeons expend in training is aimed.

Antecedentes: las tecnologías de la información y comunicación pueden aportar beneficios a la formación en cirugía de mínima invasión. Objetivo: determinar la manera más adecuada de incluir las tecnologías de la información y comunicación, en particular una plataforma de e-Learning, en un programa de formación presencial. Material y métodos: se realizó una encuesta en línea entre los asistentes al Centro de Cirugía de Mínima Invasión Jesús Usón, con preguntas relativas a las nuevas tecnologías aplicadas a la formación. Con los datos recopilados se efectuó un estudio descriptivo. Resultados: se enviaron 382 cuestionarios y se recibieron 102 (30%) correctamente respondidos. Los medios para formación teórica más empleados en la actualidad en la población estudiada son: visualización de videos quirúrgicos (85-83.3%) y la asistencia a cursos (77-75.5%). Los usuarios consideran útiles las nuevas tecnologías en formación (4.1 ± 0.9) y sobre todo usarían una plataforma de e-Learning personalizada antes y después de asistir a un curso de formación presencial (80-78.4%). Conclusiones: se propone una metodología de recursos didácticos basados en videos quirúrgicos antes y después que los alumnos asistan a un curso de formación presencial, para que mediante la aplicación de esta metodología se mejore y optimice el tiempo que los cirujanos dedican a su formación.

Effects of pneumoperitoneum and body position on the morphology of abdominal vascular structures analyzed in MRI.

PURPOSE: To analyze the complications of laparoscopy in different vascular structures using magnetic resonance imaging (MRI). MRI has become a key tool in laparoscopic surgery. During these procedures, pneumoperitoneum creation and placing the patient in the surgical position provoke different changes in the splachnic circulation. MATERIALS AND METHODS: Ten pigs were included in the study. MRI studies of the abdominal area were carried out in four different situations of abdominal pressure and body position. RESULTS: Changes in the area of the lumen of the portal vein and the abdominal aorta were analyzed in all situations. A significant reduction in the area of the abdominal aorta was observed after the pneumoperitoneum in supine and anti-Trendelemburg position. The lumen of the portal vein was significantly reduced in all analyzed situations except when placing the patient in anti-Trendelemburg without pneumoperitoneum, in which case the area was increased. CONCLUSION: The creation of pneumoperitoneum provokes morphological changes in the lumen of different abdominal vessels as a consequence of the increase of pressure. Furthermore, the combination of pneumoperitoneum together with the anti-Trendelemburg position results in a more significant reduction of the lumen of the portal vein and the abdominal aorta.

Construct and face validity of SINERGIA laparoscopic virtual reality simulator.

PURPOSE: Laparoscopic techniques have nowadays become a gold standard in many surgical procedures, but they imply a more difficult learning skills process. Simulators have a fundamental role in the formative stage of new surgeons. This paper presents the construct and face validity of SINERGIA laparoscopic virtual reality simulator in order to decide whether it can be considered as an assessment tool. METHODS: Twenty people participated in this study, 14 were novices and 6 were experts. Five tasks of SINERGIA were included in the study: coordination, navigation, navigation and touch, precise grasping and coordinate traction. For each one of these tasks, a certain number of metrics are automatically recorded. All subjects accomplished each task only once and filled in two questionnaires. A statistical analysis was made and results from both groups were compared with the Mann-Whitney U-test, considering significant differences when P < or = 0.05. Internal consistency of the system has been analyzed with the Cronbach's alpha test. RESULTS: Novices and experts positively rated SINERGIA characteristics. At least one of the evaluated metrics of each exercise presented significant differences between both groups. Nevertheless, all metrics under study gave a better punctuation to the executions accomplished by experts (lower time, higher efficiency, fewer errors. . .) than to those made by novices. CONCLUSION: SINERGIA laparoscopic virtual reality simulator is able to discriminate subjects according to their level of experience in laparoscopic surgery; therefore, it can be used within a training program as an assessment tool.