Jonas D. Larsen1, Ole Graumann1,2, Rune Jensen1
1 Research and Innovation Unit of Radiology, Department of Clinical Research, University
of Southern Denmark, Odense, Denmark
2 Department of Radiology, Odense University Hospital, Odense, Denmark
For clinical diagnostic and monitoring, point-of-care ultrasound (PoCUS) has become
a useful tool [1]. PoCUS can support clinical decision making, but for ultrasound-novices adequate
knowledge, hands-on training and proper supervision are essential. With portable ultrasound
scanners becoming increasingly available to clinicians, training is more crucial than
ever before to prevent the clinical use outpacing evidence-based education and training.
Structured ultrasound courses are already available in many locations. However, day-to-day
training during clinical practice is still the main source for developing expertise
in specialized ultrasound examinations [2]
[3]. Major challenges with this approach are the random prevalence of specific pathologies
and insufficient formal supervision/feedback due to limited resources.
Screen-based Virtual Reality (VR) simulation training ([Fig. 1A]) has partially been used to overcome these educational challenges. Screen-based
VR simulators often consist of a physical phantom simulating the patient and a computer,
generating ultrasound images based on the movement of the ultrasound probe. These
simulators provide a safe, controlled, and risk-free learning environment, where “patients”
with different abnormal sonographic findings can be scanned repeatedly. Such setups,
however, often require several physically large remedies and are resource-heavy with
pricing up to 90 000 € [4]. Their accessibility is therefore severely limited and there is a need for more
accessible VR-simulators.
Fig. 1 Illustrating the setups for different types of simulation training. A Screen based Virtual Reality simulation training. B Medical student equipped for IVR training (1 headset and 2 controllers). C Screenshot from inside the VR-HMD of how the student performs a sonographic examination
in an IVR training room showing the patient (right), student holding the probe (middle),
and the ultrasound machine displaying the patients sonographic images (left).
Immersive Virtual Reality (IVR) based on head-mounted displays (HMD) is a new simulation
modality that has shown great potential for medical education and acquisition of skills
[5]
[6]
[7]
[8]
[9]. IVR uses software to create immersive 3-dimensional interactive environments which
can be further enhanced by using a HMD with 360-degree stereoscopic field of view
([Fig. 1B, C]). In 2013 Oculus Rift introduced a new generation of consumer-priced IVR-HMDs, and
since then many other IVR-HMDs have become available, creating a nuanced and affordable
market for research and education, with pricing from 300 €. IVR-HMDs are portable,
easily accessible, require few remedies to work (1 headset and 2 controllers) and
are designed to be simple and safe to use. IVR-HMD’s can simulate any clinical setting
and any clinical procedure in a small space of 2 × 2 meters, even at home, with under
5 minutes of setup, allowing the user to learn from experience in the virtual world.
Like screen-based VR simulation training, IVR-HMD based training enables the user
to gradually progress through different levels of difficulty. This can be performed
in a realistic virtual learning environment with hundreds of different pathological
cases (even rare ones) to experience and practice without bringing harm or nuisance
to patients. Furthermore, software in IVR can provide automated, reliable, and structured
feedback allowing the user to focus further training effort on identified pitfalls
and personal challenges until an adequate level is obtained (e. g., correct interpretation
of sonographic findings of a specific disease). Many of the advocating aspects for
screen-based VR simulation training can therefore be recognized in IVR-HMD-based simulation
training, but with greater accessibility and at a lower cost making it a beneficial
supplement in ultrasound training.
A few studies have investigated the benefits of IVR-training in the acquisition of
ultrasonographic competences, such as ultrasound-guided peripheral venous catheter
placement and basic ultrasonographic skills [10]
[11]. The studies report positive learning outcomes but also agree that further research
is needed to clarify the clinical implications of using IVR as a supplementary training
tool for developing ultrasonographic competencies. It would be impractical for IVR
to replace all aspects of sonographic training; hence, it should be emphasized to
use the modality for specific and relevant learning goals such as scanning protocols,
transducer handling, adjustment of gain, depth, focus, etc., and diagnostic capabilities.
Other aspects of ultrasonographic training, such as acquiring theoretic baseline-knowledge
about a certain scanning protocol or pathology, are probably not beneficial to learn
using IVR and might not provide the same positive results compared to well-established
sources for theoretical studies (e. g., e-learning).
The research in IVR-HMD-based simulation training will hopefully continue to push
borders in a wide range of ultrasonographic settings. Aspects such as IVR-training
in more advanced form of ultrasonographic skills (e. g., FLUS, FATE, FAST) as well
as investigating the impact of such training on clinical and patient centred outcomes,
should be explored in the future. Overall, IVR-HMD simulation training has shown great
potential for improving training and education in ultrasound. However, implementation
should be preceded by research focusing on targeting efficient aspects of ultrasonographic
skills converted to IVR-training, and the transfer of acquired skills into clinical
practice.
