Key words
medical education - radiological teaching - curriculum - competency-based learning
- national competency-based catalogue of learning objectives for undergraduate medical
education - DICOM viewer
Introduction
Medical education has changed greatly in the last century. After implementation of
the basic scientific subjects in the medical curricula at the start of the 20th century,
problem-oriented learning and integrative teaching in which the separation between
basic subjects and clinical subjects was largely eliminated began in the middle of
the 20th century [1]. The most recent reform focuses on competency-based learning. The National Competency-Based
Catalogue of Learning Objectives for Undergraduate Medical Education published in
June 2015 defines different competencies to be taught to medical students [2]. According to Weinert, competencies are "cognitive skills that are possessed or
can be learned to resolve certain problems and the associated motivational, volitional,
and social readiness and ability to use these skills to successfully and responsibly
solve problems in a variety of situations" [3]. The level of learning is defined by levels. Three different competency levels that
build on one another are defined in the National Competency-Based Catalogue of Learning
Objectives for Undergraduate Medical Education ([Fig. 1]). Factual knowledge (level 1) and practical and technical knowledge (level 2) must
be achieved before practical competence (level 3).
Fig. 1 Competency levels (National Competency-based Catalogue of Learning Objectives for
Undergraduate Medical Education).
The European Society of Radiology (ESR) and German Radiological Society jointly developed
model curricula to implement the recommendations regarding competency-based teaching
in the National Competency-Based Catalogue of Learning Objectives for Undergraduate
Medical Education in radiological teaching [4]
[5]. However, the extent to which these changes can be implemented in the daily routine
is not yet clear.
Lectures using transparencies have become established for teaching various content
but have their limits when it comes to teaching content on levels 2 and 3. This format
lacks active student participation and practical training. Practical teaching has
long been established in subjects such as anatomy and pathology. As a result of increasing
digitalization, the technical requirements for practical teaching are now also met
in radiology. Therefore, it makes sense to integrate a radiological DICOM viewer into
teaching thereby making radiological teaching more practical. This type of teaching
is not yet common and has only been reported in a few studies [6]
[7]
[8]
[9]
[10]
[11]
[12].
We established two interactive competency-based radiology courses in which students
independently and systematically view, analyze, and present radiological examinations
on computers with a DICOM viewer under supervision of an instructor.
The goal of this study was to evaluate the newly established courses regarding practical
feasibility, acceptance by students and instructors, and implementation of competency-based
teaching as required by the model curriculum of the German Radiological Society and
the National Competency-Based Catalogue of Learning Objectives for Undergraduate Medical
Education.
Materials and Methods
Both evaluated courses were conducted at Hannover Medical School as part of the model
course HannibaL (Hannoveraner integrierter, berufsorientierter und adaptiver Lehrplan). Beginning
in academic year 2015/16, an elective course was established and incorporated in the
usual radiology lecture in the 5th year. The average class size was approximately
20 students per course. The course included three 90-minutes sessions per quarter.
Due to the success of this course, it was included in the curriculum as a regular
course starting in academic year 2016/17 and an obligatory course for all students
in the 4th academic year was additionally created. This course had a class size of
25 students and included two 180-minute sessions. Both courses were conducted in a
multimedia room equipped with 25 PCs ([Fig. 2]). The server-based radiology DICOM viewer (Visage Imaging®, Pro Medicus Limited, Richmond, Australia) that we used is also used in the clinical
routine. The viewer allows students to use all techniques available to clinical radiologists,
e. g. interactive multiplanar reconstruction, distance measurements, measurements
in Hounsfield units, and maximum/minimum intensity projections ([Fig. 3]). A special login gives students access to anonymized teaching cases but not to
the entire PACS. The cases are transferred to this restricted teaching area and anonymized
directly with the DICOM viewer. Since this is a server-client solution, complicated
transfer or import of cases is not necessary. In addition to pathological cases, annotated
teaching cases were used study normal anatomy ([Fig. 3a]). Desktop monitoring software (Netop Vision®, Netop, Birkerod, Denmark) made it possible to project the screen of a student's
PC so that the case could be discussed jointly as a group.
Fig. 2 The course was conducted in a multimedia room equipped with 25 computers.
Fig. 3 Desktop of the DICOM Viewer (Visage Imaging®) a Cross-sectional CT images with anatomical annotations; b Multiplanar reconstruction for generation of a "virtual" chest X-ray. Left: axial
sections of a lung carcinoma in the left lower lobe (3 mm slice thickness). Coronal
(middle) and sagittal (right) reconstructions (100 mm slice thickness). Arrows point
to lung carcinoma in the left lower lobe.
Plain radiographs and/or CT scans of the skull, thorax, abdomen, and skeleton or CT
scans of the thorax and abdomen were analyzed with DICOM viewer software in the elective
and obligatory course, respectively. To represent the principle of practical competency-based
teaching, an exemplary selection of treated topics with the corresponding competency
level and the learning objectives of the model curriculum and the National Competency-Based
Catalogue of Learning Objectives for Undergraduate Medical Education is presented
in [Table 1]. The students interactively studied 5 – 8 cases (elective course) and 5 – 6 cases
(obligatory course) per course using DICOM viewer and desktop monitoring software.
The ratio of classroom teaching to practical teaching was approx. 1:1. The format
is explained using chest X-rays as an example: PowerPoint was initially used to teach
the basic principles of the acquisition technique and of the systematic evaluation
of a chest X-ray ([Table 1], level 1). This was followed by a short introduction to the DICOM viewer and its
basic functions ([Table 1], level 2). To learn cross-sectional anatomy, the students used the DICOM viewer
to independently view a chest CT with annotated anatomical structures ([Table 1], level 2, [Fig. 3a]). In the subsequent demonstration of pathological cases, the students applied their
acquired image analysis skills and used the DICOM viewer to present pathological findings
on the chest X-ray. Students then presented each case individually to the group via
desktop monitoring software ([Table 1], level 3a). The differential diagnoses were evaluated and the final diagnosis was
determined during case demonstration with the help of the instructor. The students
then presented the corresponding CT scan ([Table 1], level 3a) and applied previously acquired skills such as measurement of Hounsfield
units ([Table 1], level 3a). To be able to better understand projection radiography, coronal and
sagittal reconstructions were performed by all students to generate „virtual“ X-rays
from the CT scan ([Table 1], level 2, [Fig. 3b]). Following joint analysis of the cases, the instructor used PowerPoint to teach
additional theoretical content regarding the disease ([Table 1], level 1).
Table 1
Selective topics of the practical competency-based radiological teaching with respect
to the learning objectives of the model curriculum for radiological teaching (DRG)
and of the national competency-based catalogue (NKLM).
|
Topics
|
PowerPoint
|
DICOM viewer
|
Desctop monitoring software
|
Competency level
|
Learning objectives model
Curriculum of the German Radiological Society
|
Learning objectives
National Competency-Based Catalogue of Learning Objectives for Undergraduate Medical
Education
|
|
Anatomy, thorax:
|
|
|
|
|
R-1.2 – In-depth knowledge of the normal anatomy of various organs and structures
on X-ray images – knowledge of the normal cross-sectional anatomy on CT – reliable
identification of normal anatomical structures on X-ray images and CT scans
R-2.2 – Knowledge of the normal anatomy of the heart and vessels on X-ray images and
CT scans – reliable identification of normal anatomical structures on chest X-ray
images
R-2.3 – Knowledge of the normal anatomy of the respiratory system and lungs, heart,
large vessels, mediastinum, and thoracic wall on chest X-ray images and on CT scans
– identification of the following structures on posterior-anterior (p. a.) and lateral
chest X-ray images: Fissures and lobar boundaries of the lung, trachea, main bronchia,
atria and ventricles of the right and left heart, pulmonary arteries, aorta, mediastinal
parts and diaphragm
|
15.4.1.6 – die Absolventin und der Absolvent können relevante anatomische Strukturen
in Röntgenaufnahmen erkennen und benennen (Lungenlappen und -grenzen, Trachea und
Carina, Herz mit grenzdefinierenden Strukturen, Pulmonalarterien, Aorta, V. cava sup.,
V. azygos, Wirbelsäule, Rippen, Claviculae, Scapulae, Humeri, Sternum, Recessus)
15.4.1.10 – die Absolventin und der Absolvent können relevante anatomische Strukturen
in computertomografischen Schnittbildern erkennen und benennen.
|
|
|
x
|
-
|
-
|
1
|
|
|
x
|
-
|
-
|
1
|
|
|
-
|
x
|
-
|
1, 2
|
|
|
-
|
x
|
-
|
1, 2
|
|
|
x
|
x
|
-
|
1, 2
|
|
|
-
|
x
|
-
|
1, 2
|
|
Aortic dissection
|
|
|
|
|
R-1.3 – Understanding of the acquisition times after bolus administration of contrast
agent and their relevance for the particular issue – ability to identify whether a
CT scan is contrast-enhanced.
R-2.2 – Knowledge of the normal dimensions of the aorta and the classification of
aortic aneurysms and dissections.
|
15.4.1.7 – Graduates can identify and describe relevant pathological changes on X-ray
images (mediastinal enlargement).
15.4.1.11 – Graduates can identify and describe relevant pathological changes on CT
scans (aortic dissection).
|
|
|
x
|
-
|
-
|
1
|
|
|
x
|
-
|
-
|
1
|
|
|
x
|
-
|
-
|
1
|
|
|
-
|
x
|
x
|
1, 2, 3a
|
|
|
-
|
x
|
x
|
1, 2, 3a
|
|
|
x
|
x
|
x
|
1, 2, 3a
|
|
|
x
|
-
|
-
|
1
|
|
Mediastinal tumors
|
|
|
|
|
R-1.2 – Understanding of Hounsfield units and their scaling – Knowledge of the normal
attenuation values in Hounsfield units for important tissue and pathologies – measurement
in Hounsfield units on CT scan and identification of corresponding tissue properties.
R-2.3 – Knowledge of the visualization of various mediastinal masses on chest X-ray
images and CT scans
|
15.4.1.7 – Graduates can identify and describe relevant pathological changes on X-ray
images (mediastinal enlargement).
15.4.1.11 – Graduates can identify and describe relevant pathological changes on CT
scans (mediastinal lymph nodes).
|
|
|
–
|
x
|
x
|
1, 2, 3a
|
|
|
x
|
x
|
x
|
1, 2, 3a
|
|
|
–
|
x
|
x
|
1, 2, 3a
|
|
|
–
|
x
|
x
|
1, 2, 3a
|
|
|
–
|
x
|
x
|
1, 2, 3a
|
|
|
x
|
–
|
–
|
1
|
|
Intracerebral hemorrhage
|
|
|
|
|
R-2.9 – Understanding of typical radiological changes in hemorrhagic stroke on CT
scan – Identification and differentiation of different types of intracranial hemorrhage
on CT scan.
|
15.4.1.11 – Graduates can identify and describe relevant pathological changes on CT
scans (differentiation of EDH, SDH, subarachnoid hemorrhage,
intracranial hemorrhage on CT scan).
|
|
|
x
|
–
|
–
|
1
|
|
|
–
|
x
|
x
|
1, 2, 3a
|
|
|
x
|
–
|
–
|
1
|
|
|
–
|
x
|
x
|
1, 2, 3a
|
|
|
x
|
–
|
–
|
1
|
|
|
–
|
x
|
x
|
1, 2, 3a
|
|
|
x
|
–
|
–
|
1
|
|
|
–
|
x
|
x
|
1, 2, 3a
|
|
|
x
|
–
|
–
|
1
|
An anonymous online survey (SurveyMonkey®, Dublin, Ireland) was performed immediately after the courses. Students were able
to rate their overall satisfaction with the course on a scale of 1 to 6. In addition,
students were asked to rate on a scale of 1 – 5 how easy it was to use the DICOM viewer,
whether the course helped to improve their knowledge of cross-sectional anatomy and
radiological findings, whether the combination of DICOM viewer and classroom teaching
was superior to teaching via PowerPoint alone, and whether the course helped to increase
their interest in radiology. Students were also able to write comments about the course
and express ideas and criticisms. In the elective course, students were asked whether
they would be in favor of a new practical competency-based course being established
and in the obligatory course they were asked whether they considered the course to
be relevant to their future occupation.
Instructors rated the course retrospectively on a scale of 1 – 6 via an online survey
(SurveyMonkey®). Moreover, the instructors were asked to rate possible advantages and disadvantages
of practical competency-based teaching on a scale of 1 – 5. Improved teacher-student
interaction, better understanding of the DICOM viewer and cross-sectional images,
improved understanding of radiologic findings, greater understanding of course content,
increased learning success due to active student involvement and higher motivation
on the part of the students were included in the survey as advantages. Greater preparation
effort, insufficient time for theoretical content, distraction due to the computers,
worse preparation for MC tests, and worse teaching of structured content were included
in the survey as disadvantages. Moreover, use of the DICOM viewer during teaching
was rated on a scale of 1 to 5.
Results
A total of 260 students (160 students in the elective course and 100 students in the
obligatory course) participated in the survey. Since attendance was only documented
in the obligatory course, a response rate could only be determined for this course
(86 %). The overall rating of the courses was positive: the elective course and the
obligatory course were rated as excellent by 27 % and 10 %, very good by 41 % and
30 % and good by 28 % and 52 %, respectively ([Fig. 4a]). 94 % (elective course) and 99 % (obligatory course) of the students stated that
use of the DICOM viewer in the course was feasible ([Fig. 4b]). Almost all students felt that the course improved their understanding of cross-sectional
anatomy (97 % in elective course, 95 % in obligatory course) and radiologic findings
(97 % in elective course, 98 % in obligatory course) ([Fig. 4c-d]). Teaching with a combination of PowerPoint and DICOM viewer is superior to teaching
with PowerPoint alone (98 % in elective course and 95 % in obligatory course, [Fig. 4e]). 61 % of the students in the elective course and 65 % of the students in the obligatory
course indicated that the course increased their interest in radiology, while 32 %
in both courses were undecided ([Fig. 4f]). 98 % of the students in the elective course rated the establishing of a practical
competency-based radiology course with a DICOM viewer as extremely or very useful
([Fig. 4 g]). 92 % of the students in the obligatory course felt that the course was very relevant
or relevant for their future occupation ([Fig. 4 h]). The interaction with instructors and independent viewing and presentation of cases
were rated positively in the comments. Suggestions for improvement included more time
for the introduction to the program, a greater number of cases and the option to independently
prepare and post-process cases on suitable workstations.
Fig. 4 Results of student evaluation of elective (n = 160) and obligatory course (n = 100):
Results of MC questions a–h.
9 instructors participated in the instructor survey (response rate 75 %). The instructors
also rated the competency-based radiology course using a DICOM viewer positively:
44 % as excellent, 33 % as very good, and 23 % as good ([Fig. 5a]). The majority of instructors (89 %) stated that it was feasible to use a DICOM
viewer in the course, while one instructor (11 %) disagreed primarily due to unexpected,
temporary technical difficulties (network failure) ([Fig. 5b]). The instructors indicated the following as advantages: interaction with students
(100 %) and improved understanding of radiological findings (89 %) ([Fig. 5c]). The instructors spent approximately 50 % of the overall course time speaking compared
to 90 % in a conventional lecture (not shown). The majority of the instructors (56 %)
stated the following as a disadvantage of the course: greater preparation effort than
in a conventional lecture. However, 44 % of the instructors did not share this opinion
([Fig. 5 d]). Only one instructor found the teaching of theoretical content insufficient. None
of the instructors felt that the teaching of structured content was worse than in
a conventional lecture. The majority of the instructors (67 %) did not observe increased
distraction of the students due to the computers, while 33 % of the instructors were
undecided. The majority of the instructors (56 %) did not notice worse preparation
for MC tests, 33 % were undecided, and one instructor (11 %) was concerned about worse
preparation.
Fig. 5 Results of evaluation of instructors (n = 9, a–d).
Discussion
The goal of our study was to evaluate the newly established practical competency-based
radiology course with respect to practical feasibility, acceptance by students and
lecturers, and competency-based radiological teaching with respect to the model curriculum
of the German Radiological Society and the National Competency-Based Catalogue of
Learning Objectives for Undergraduate Medical Education.
We were able to show 1) that practical competency-based radiological teaching is very
feasible and has high acceptance among students and lecturers, 2) that the course
aroused interest in radiology among the majority of the students, 3) that students
report improved understanding of cross-sectional anatomy and radiological findings,
and 4) that this type of teaching fosters competency-based teaching as proposed by
the model curriculum of the German Radiological Society and the National Competency-based
Catalogue of Learning Objectives for Undergraduate Medical Education.
While the learning objectives in the National Competency-based Catalogue of Learning
Objectives for Undergraduate Medical Education and the model curriculum of the German
Radiological Society are clearly defined, it is not yet clear how competency-based
teaching can be efficiently implemented in radiology. The practical competency-based
teaching presented in this study represents one possibility. Students learn how to
use a DICOM viewer, implement their learned factual knowledge in practice, and present
cases via desktop monitoring software in front of the group under the supervision
of the instructor. This requires different levels. Students must acquire basic factual
knowledge (level 1) as well as practical and technical knowledge (level 2) and independently
demonstrate pathological and non-pathological radiological findings under supervision
(level 3a). In particular, this addresses the role of the medical expert as defined
in the National Competency-based Catalogue of Learning Objectives for Undergraduate
Medical Education.
To date, there are only a few studies investigating the use of interactive image analysis
on a DICOM viewer in the teaching of students even though simple DICOM viewers are
now available as freeware for all operating systems and are used at almost all clinics,
even by non-radiologists. Strickland used the free Mac-based DICOM viewer Osirix to
set up a virtual workstation on which students could independently view cases from
the musculoskeletal region [6]. The usability of Osirix as a teaching platform for radiologists was also emphasized
by Rojas who generated a case collection of interstitial pulmonary diseases and implemented
pathology reports, clinical findings, and radiological findings in the DICOM data
set [10]. Additional studies used a DICOM viewer to improve understanding of anatomy and
cross-sectional anatomy [7]
[8]
[9]
[10]
[11]
[12]. Alvarez conducted an introductory course in radiologic anatomy using the freely
available iPACS DICOM viewer. Anatomical structures were annotated in the CT data
set in small groups and the results were discussed with the entire group via desktop
monitoring software [7]. In a further study, donated bodies were examined with CT prior to being dissected
by students in the macroscopic anatomy course [8]. Integrative classes in anatomy and radiology in which images are interactively
analyzed are being offered as part of preclinical education at multiple medical schools
in Germany [13]. For their study Schober et al. used the Osirix DICOM viewer which is also available
free of charge for the iPad [12]. A study from Japan used the same method to compare the body anatomy to the CT anatomy
during dissection in the anatomy course [11].
Interactive teaching using a DICOM viewer is more established in post-graduate medical
training than in student education. DICOM-based standardized test methods have been
evaluated in a number of studies to measure the competence of prospective radiologists
on the basis of simulated emergency CT cases [14]
[15]
[16]
[17]. In particular, the possibility to simulate emergency situations prior to being
on call was considered useful by participants [17]. The interaction when viewing DICOM data sets [7]
[10]
[16] and the high acceptance by study participants were considered significant advantages
in these studies as well as in our results.
Why isn't the use of DICOM viewers in student education more common? This is probably
due to issues of the past, such as a lack of technical infrastructure, inflexible
systems requiring resources for operating the DICOM viewer, and concern about preparation
effort. Digital image storage systems in radiology have only been widely available
for about 15 years and image export and anonymization for teaching purposes used to
time-intensive. DICOM viewers are now readily available in radiology and are flexible
as a result of the use of client-server solutions. In the case of the DICOM viewer
that we used, anonymization and assignment to the teaching archive can be performed
in one step without significant effort. By using iOS-based mobile devices, PDFs and
photos (surgery images, pathological specimens) can also be integrated simply and
intuitively. A further advantage is the use of the same DICOM viewer as in the clinical
routine so that instructors do not require additional training and students have easier
access during the clinical electives, subinternship and practical year.
An alternative to the software that we used is the free Mac-based DICOM viewer Osirix.
For example, radiologists in Great Britain have already recognized the potential of
this software for teaching. There is a user group of approx. 265 registered users
who exchange anonymized DICOM teaching cases via Osirix and use them for teaching
and examination purposes [18].
In our opinion a number of conditions must be met to be able to successfully establish
practical competency-based teaching. A multimedia room with a sufficient number of
PCs must be available. Desktop monitoring software allowing case presentation by individual
students is also required. Moreover, the DICOM viewer must allow current functions
such as multiplanar reconstruction and quick and uncomplicated generation of teaching
cases to minimize preparation effort.
As a result of the reforms initiated by the National Competency-based Catalogue of
Learning Objectives for Undergraduate Medical Education, examination formats will
also change. Objective structured clinical examinations (OSCEs), which test skills
regarding the patient interview and clinical examination in particular, have already
been instituted at some universities. To date, radiology is rarely represented in
these examinations. The interactive platform described in this study offers optimal
conditions for conducting OSCEs in radiology under standardized conditions. Conceivable
further developments of the course concept include blended learning and flipped classroom
approaches in which students independently acquire theoretical content in advance,
e. g. through online material, in order to be optimally prepared for practical teaching.
It is noteworthy that the majority of the students were in favor of the establishment
of a new obligatory seminar for students despite the increased time requirement –
a clear endorsement of the teaching format. Due to the positive feedback, image analysis
training has been included in the curriculum as an obligatory course since the 2016/17
academic year.
Our study has some limitations, the most important being that a comparison group was
not studied prospectively. However, a two-arm prospective design was not possible
due to differences in treatment and a cross-over design was not possible due to the
time limitations in the radiological curriculum.
In summary, our results show that practical radiological teaching on PCs using a DICOM
viewer and desktop monitoring software is an innovative approach with high acceptance
among students and instructors and good practical feasibility. The competency-based
teaching proposed by the National Competency-Based Catalogue of Learning Objectives
for Undergraduate Medical Education and the model curriculum of the German Radiological
Society can be implemented in this way.
