Teleradiology:
Not always plug & play - A case report
Uwe Engelmann, Andre Schroter, Harald Evers, Markus
Schwab, Ulrike Baur, Hans-Peter Meinzer
Abteilung
Medizinische und Biologische Informatik,
Deutsches Krebsforschungszentrum.
in cooperation with
Steinbeis-Transferzentrum Medizinische Informatik,
Heidelberg, Germany
The German Cancer Research Center and the Steinbeis Transfer Center for Medical Informatics in Heidelberg, Germany, cooperatively developed the teleradiology system MEDICUS and it's commercial successor CHILI. The establishment of the teleradiology network started in January 1996. More than 20 sites are currently connected and are using the system in clinical routine. More than 100,000 images have been processed in this network. The teleradiology system has been used nearly 10,000 times and the users discussed the images in more than 1,000 teleconferences cooperatively.
More than twenty modalities (CT and MRI) of four different vendors (Siemens, GE, Philips, Toshiba) are now connected. The DICOM standard is the method of choice for the export of the data from the imaging modalities. But most of the existing modalities still do not have a DICOM interface. Therefore, we need in many cases practical solutions which take into account the propriety standards of the vendors and network protocols which are not state of the art. This paper is a case report which describes the realized teleradiology solution between two German hospitals.
The "Luther-Krankenhaus" in Essen in north west Germany is a small hospital with a CT in the department of internal medicine. The latter has no full time radiologist. Therefore it was desired to send the CT scans to the hospital "Alfried-Krupp-Krankenhaus" in the same town where the radiologists would report the images. Furthermore, all MRI scan of inpatients of the Luther hospital which have been scanned and reported at Krupp should be send to the Luther hospital.
The CT scans are produced on a Philips Tomoscan RS/6000. This is in fact a japanese CT scanner without digital interfaces. Even Philips has not much information about it. (David Cluny, the "medical image format guru" says about Philips CTs: "big black hole".) Images are printed on an Agfa laser camera. The laser camera gets the images as screen shots of the console video monitor which are grabbed with a frame grabber, MG3000 (Agfa). The other hospital were the images should be sent to has an advanced network of DICOM compatible modalities, mainly with Siemens devices. The plan was to report and process the images at the Siemens MagicView workstation (Version VA 31, patch level B2).
The best source for the CT images was the MG3000, where the digitized video image of the console was available. The MG3000 has no DICOM interface for image export (e.g., C-Store User) but a propriety interface was available. A small company in Essen was able to read the interface with a PC, get an image bitmap (8 bit, 1024x1296 pixels) without any alphanumeric information and to convert it into a DICOM secondary capture image. The images are transferred to the CHILI workstation via the ftp-protocol. CHILI reads the images and scales them to a quarter of the original size. An optical character recognition (OCR) program reads the overlay characters in the image bitmap to create at least the basic demographic data of the patient and study data. A more complete DICOM image is created then based on this information. CHILI uses this information to store the images in the DICOM-oriented patient database.
The user can submit single images, studies or series via CHILI to the MagicView in the other hospital. The ISDN network is used to connect both hospitals. The CHILI workstation is a Silicon Graphics Inc. Indy running IRIX 6.2 with an internal basic rate interface which is connected to an S0 adapter of the Telekom. An ISDN router (Ascend Max 1800) is the entry point to the Krupp hospital. The MagicView receives the images as C-Store-Provider and can display and process the Philips images. MRI images can be sent back to the CHILI workstation on the other side.
The technical challenges were that the CT had no digital interfaces. This could be solved with the MG3000. The disadvantage of this device was that it had only a propriety interface. The bitmap of the image could be read and converted to DICOM. The next hurdle was the missing alphanumeric data which were obtained with an OCR program. The DICOM protocol could then be used for the further communication.
There was also an organizational challenge. Two hospitals and six companies were involved. Several people from sales and support of each company had to work in the project. The big companies had no real interest in getting the system running, as the financial outcome was to small or they had not the technical expertise. Therefore they delegated it to smaller companies.
The hospitals have several advantages, like less film transports per taxi, reduced transport time, and the possibility of central digital archiving. Disadvantages are: The strong security concept of CHILI had to be given up as this is not part of the DICOM standard. Teleconferences are not possible with a MagicView. The reports can not be written and transferred from the MagicView to CHILI. The users have to change the communication medium when they want to exchange textual information. The maintenance of this complex solution may cause future problem in case of technical failures as the responsibility may be not clearly defined.
A complex chain of components has been connected. The system was operational end of March 1998. Clinical routine started mid April. More than 1,000 images have been sent in the first four weeks. The system is working reliable and stable. The users are happy.
Deutsches Krebsforschungszentrum
Abteilung Medizinische und Biologische Informatik
H0100, Im Neuenheimer Feld 280,
69120 Heidelberg,
Tel: 06221 / 42 2354, FAX 06221 / 42 2345
e-mail: U.Engelmann(at)dkfz-heidelberg.de
Oral presentation at EuroPACS'98, Barcelona, Spain