Augmented-reality communication for diagnostic tasks in cardiology.

In the CardiAssist project, a teleconsultation module has been implemented that uses both ultrasound images and three-dimensional (3-D) animated heart models as common artifacts to support communication between medical professionals. Real images and conceptual models are linked as "augmented reality" so that the models provide orientation for diagnostic tasks in cardiology. Hypotheses or results can be documented on the image or the abstract level, as the heart model can be modified to include pathological details. In teleconsultation, pointing references accelerate communication between physicians of different backgrounds.

Intelligent training system integrated in an echocardiography simulator.

Computer simulators play an important role in medical education. We have extended our simulator EchoComJ with an intelligent training system (ITS) to support trainees adjusting echocardiographic standard views. EchoComJ is an augmented reality application that combines real three-dimensional ultrasound data with a virtual heart model enabling one to simulate an echocardiographic examination. The ITS analyzes the image planes according to their position, orientation and the visualization of anatomical landmarks using fuzzy rules. An adaptive feedback is provided that colors the specific anatomic landmarks within the contours of the virtual model based on the quality of the image plane.

An enabling system for echocardiography providing adaptive support through behavioral analysis.

Echocardiography requires the integrated application of a broad spectrum of cognitive and practical skills, e.g. diagnostic knowledge (symbolic), image interpretation (visual perception) and handling of the ultrasound probe (sensorimotor). This complex expertise is acquired through extensive practical training guided by a skilled cardiologist that is often incompatible with clinical reality. Especially for beginners, the most critical point during an echocardiographic examination is the steering of the ultrasound probe to navigate between different cardiological standard planes (sensorimotor skill) without loosing orientation. These transitions or "standard trajectories" can roughly be described by specific movement patterns. We propose an enabling system based on an Augmented Reality simulator for two-dimensional echocardiography imitating this apprenticeship [1]-[3]. During a simulated ultrasound examination the system monitors the activities of the trainee and analyzes the motion pattern of the ultrasound probe. The simulator reacts by mapping the motion patterns onto cognitive orientation demands and providing adaptive feedback in the form of context sensitive help (animations). It partly takes the role of the critical teacher.

Simulation of congenital heart defects: a novel way of training in echocardiography.

BACKGROUND: Echocardiography is one of the most important diagnostic imaging modalities in paediatric cardiology. Owing to the large number of lesions, achieving expertise often requires years of training. Echocardiography is still taught using the apprenticeship model, which is time- and personnel consuming. OBJECTIVES: To extend the echocardiography simulator EchoCom to enable simulation of congenital heart lesions and validate it for training in paediatric echocardiography. METHODS: The simulator consists of a life-size manikin, a dummy transducer with attached three-dimensional (3D) tracking system and a computer application. Transthoracic real-time (RT) 3D echocardiographic datasets were collected and embedded into the simulator. Two-dimensional images were calculated and resliced from these datasets according to the position of the tracking sensor. Ten RT 3D datasets of congenital heart lesions were selected for validation. Datasets were blinded and without additional information presented to 43 participants who were stratified according to their expertise (12 experts, 16 intermediates, 15 beginners). Participants were asked to list the relevant findings and make a diagnosis. Construct validation was tested comparing diagnostic performance for each group. Face and content validation were tested using a standardised questionnaire. RESULTS: Participants judged the simulator as realistic and useful. The main drawback was the adult size of the manikin. The diagnostic performance of each group differed significantly proving construct validity. CONCLUSIONS: According to this validation the prototype simulator could make a significant contribution to training in the use of echocardiography in congenital heart disease.

EchoComTEE - a simulator for transoesophageal echocardiography.

Transoesophageal echocardiography (TOE) requires extensive hands-on training, and it is for this purpose we have designed EchoComTEE, a simulator for TOE. It consists of a manikin and dummy probe; according to the position of the dummy probe (tracked by an electromagnetic sensor), two-dimensional (2D) images are calculated from three-dimensional (3D) data sets. Echocardiographic images are presented side-by-side with a virtual scene consisting of a 3D heart, probe tip and image plane. In this way the trainee is provided with visual feed-back of the relationship between echocardiogram and image plane position. We evaluated the simulator using a standardised questionnaire. Twenty-five experts and 31 novice users participated in the study. Most experts graded the simulator as realistic and all recommended its use for training. Most novice users felt the simulator supported spatial orientation during TOE and, as anaesthetists often do not have training in transthoracic echocardiography, in this group the TOE simulator might be particularly useful.