G. Eysenbach, J. Bauer, A. Bittorf, T.L. Diepgen
Dermatological University Hospital Erlangen
Dept. of Medical Informatics, Epidemiology and Public Health
Hartmannstr. 14
D-91052 Erlangen
Gunther.Eysenbach@derma.med.uni-erlangen.de
We describe the development of an image database DOIA (Dermatological OnlIne Atlas) and present several spin-off projects using images of the atlas, e.g. student education using the atlas, a patient information system named Dermatology Internet Service (DermIS) and a experiment to collect epidemiological data from patients with dermatological diseases.
The database (http://derma.med.uni-erlangen.de) contains
about 3.000 clinical images covering more than 500 dermatological
diagnoses. It is designed for worldwide use; international submissions
are encouraged. One aim of the project is to compile an international
reference for dermatological images, containing images of high
educational quality, but also covering pathological conditions
on different skin types and rare diagnoses which are not commonly
illustrated in ordinary textbooks. All images are mapped to a
modified ICD-9 key; in addition a subset of images are mapped
to hierarchical keys for location, physical attributes of the
location and clinical and histopathological features of the lesion.
A differential diagnosis mode is currently being implemented.
Introduction. Dermatology is a specialty which heavily depends on the clinical aspect of the disease. Due to space limitations and the high costs of printing colored images, traditional textbooks are very limited both in the scope of diagnoses illustrated ("width") as well as regarding the variety of images presented per diagnosis ("depth"). As the same disease may look very different in different stages of a disease or on different skin types, medical students and doctors in training have to see a high number of patients in order to get the "full picture" on the various possible phenotypes of a given disease or need access to a comprehensive image collection. One way to facilitate access to a high number of images is to store them in computers and to make them accessible via the WWW.
To create an electronic, international reference for dermatological images we developed an image database DOIA (Dermatological OnlIne Atlas), designed for worldwide use. The atlas contains images of high educational quality, but also covers rare diagnoses and pathological conditions on different skin types, which are commonly not found in ordinary textbooks. Several spin-off projects already make use of the images of the atlas: 1. medical student education: the image atlas is used in our student courses, in which we also evaluated the prerequisites and abilities of students for using the atlas, 2. patient education: images from the atlas are used for educating patients via the internet, 3. a research project has been initiated in order to evaluate the internet as a tool for obtaining epidemiological data from patients with atopic eczema; images from the atlas and the patient education system are used to draw a high number of patients with atopic eczema to our website, and medical data from these patients are collected using HTML-questionnaires.
Methods. Images are mostly selected from our hospital archive containing 40000+ slides and hard copies but are also comprised of international submissions. Slides and hard copies have been digitized and stored on Kodak photo compact disks. For inclusion into the database images are compressed using JPEG-compression. A relational database (1) was developed containing the image and additional information, such as description keys, information about the patient, physician etc. All images are mapped to a modified ICD-9 key; in addition a subset of the images are described using hierarchical keys for location, physical attributes of the location relevant to the disease (e.g. "exposed to sunlight"), a description of the clinical and histopathological features of the lesion. A differential diagnosis mode is currently being implemented, which roughly groups diagnoses according to their morphology and which will point users to images with a similar morphology.
Besides of being a reference resource for residents and specialists, the database is used for undergraduate training of medical students in their 5th year dermatological course. In order to assess the prerequisites of students for using the database, computer literacy and technical equippment of medical students at home as well as their attitude towards computer-based training were evaluated using a questionnaire. The questionnaire was also used to evaluate the acceptance of the WWW-atlas among students.
Using images from the database an additional patient information system named Dermatology Internet Service (DermIS) was developed using static HTML-pages, currently focussing on skin cancer and atopic eczema.
As our webpages attract a considerable number of patients suffering from diseases covered in our DermIS (skin cancer and atopic eczema), an experiment is currently conducted to use this popularity to obtain clinical and epidemiological data directly from patients and healthy controls who are visiting the website. This is done by presenting form-based questionnaires to visitors. In order to confirm our hypothesis, that the quality of data obtained via the WWW is comparable with those obtained by traditional paper-based questionnaires, we include questions in our WWW-based questionnaires which have previously been delivered on a paper-based questionnaire to a population of patients in the clinical setting. Once the reliabilty of this novel method has been confirmed, one may use this method to reach a great number of patients from different countries in order to obtain "new" medical and epidemiological information from a population which is different than the usual patient population seen in out- and in-patient.departments of university hospitals.
Results, Discussion and Conclusions.
Image database: The database contains about 3.000 clinical images covering more than 500 dermatological diagnoses. We currently receive more than 16.000 hits per day, the majority of accesses coming from the US.
Medical student training: Results of the questionnaire survey and comparison with a study about computer literacy among medical students conducted five years ago using a similar questionnaire (2) showed that computer literacy, technical prerequisites, attitudes towards computer-based training and interest in telecommunication among medical students (as a prerequisite for them using the atlas) improved significantly during the last 5 years. A electronic atlas on the WWW therefore is a valuable tool for student education. The atlas was rated significantly better than other form of teaching such as electronic lectures, MC-questions and case reports.
Patient education: The patient information system is being used by a large number of patients.
The patient education system is currently also used
to obtain clinical and epidemiological data from patients with
atopic eczema. For example, we question patients about presence
or non-presence of constitutional stigmata of atopy (dry skin,
infraorbital fold, rarefied eyebrows etc.), anamnestic data and
other physical findings (illustrated by images from the electronic
atlas), allowing us to calculate a prevalence of these findings
among the population questioned. Preliminary data indicate that
this may be a valuable method to obtain medical data from patients
with minimal forms of the disease which are less frequently seen
at university hospitals for research purposes.
1. Bittorf A, Krejci-Papa NC, Diepgen TL: Development
of a dermatological image atlas with worldwide access for the
continuing education of physicians, Jornal of Telemedicine and
Telecare 1995; 1: 45-53
2. Eysenbach, G.: Computereinsatz und Computerkenntnisse unter Medizinstudenten (Computer use and computer literacy among medical students). Informatik, Biometrie und Epidemiologie in Medizin und Biologie 26 (1): 56-66; 1995