A mechanism for the direct import and JPEG conversion of Radiology PACS DICOM images has been established for the following reasons.
Xray Archiving
Recently, the Radiology LAN (local area network) has extended a 100 MB ethernet connection to a node in the MCS Orthopaedic Brooks Center. The Radiology LAN is a subnetwork of the VUMC network.
In addition to the usual routing of digitized xray images (DICOM files) to the Radiology Department's DICOM Archive, Radiological DICOM devices (such as CR (computerized radiography and CT units) may now also route the same digitized xrays to a G3 Macintosh server (DicomSrv) connected to the extension of the Radiology LAN in the Brooks center. DicomSrv uses Digital Jacket, a DICOM compliant Storage Service Class Provider, to 'listen' for storage requests from appropriately configured DICOM devices on the Radiology network and stores copies of such images within the "Incoming" desktop folder on the DicomSrv Macintosh G3.
As depicted above, the "Incoming" desktop folder is also designated as a GraphicConvertor application "drop" folder which immediately JPEG converts all incoming DICOM images, transfers the DICOM header demographic data to the JPEG "Comments" window and moves the converted JPEGS into an "INJPG" desktop folder. Using a "folder action", the addition of any new JPEG file to the "INJPG" desktop folder triggers a cyclic Hypercard Hypertalk and Applescript mediated process which directs GIFConvertor to open, read and parse the DICOM demographic header data (in the JPEG "Comments" window).
With the extraction of the medical record number, a Hypercard/FileFlex look-up of a corresponding in-patient record is performed across the Radiology sub-network and VUMC Hospital network amongst the patient data stored on the "OrthoMac" Macintosh G3 server. If a matching record is not found within 48 hours, the JPEG file in question is deleted from the "INJPG" folder on DicomSrv.
If a corresponding patient record is found, a Rinaldi Hypercard external command (URLAccess) is called to create a new image record in a Filemaker Pro web served "ortx.fp3" database inputting the parsed demographic DICOM header data. The path to the corresponding JPEG file which is copied over the network to the "OrthoMac:Trauma Register:JPGA" folder is also specified within the Filemaker Pro record in such a way that web page representation of the record includes a hyperlink which opens the associated image in a java and javascripted image viewing window.
Through Hypercard FileFlex external commands, the parsed demographic DICOM header data is written to the "trdb.dbf" Fox Pro table within the "Trauma Register:TR Fox" folder on "OrthoMac" in such a way that the image may be opened and edited by Hypercard mediated image viewing (JPEGView) and editing (GraphicConvertor) applications.
CT and MR Archiving
The procedure in terms of landing DICOM CT or MR files (slices) on the DicomSrv Macintosh G3 server and the conversion of such slices to JPEG format is similar to that described above for Xrays.
Once a DICOM CT or MR slice is JPEG converted and moved to the "INJPG" folder, a "folder action" activates Hypercard to read each file's DICOM header data with the "GIFConvertor" application. Files with names containing "CT" or "MR" are moved to a newly created folders with names derived from the study type + the file medical record number (e.g. CTP4251435) within a DicomSrv desktop "QTs" folder.
Upon the completion of cycling through and processing of all files in the "INJPG" desktop folder, Hypercard is directed to the "QTs" desktop folder. If a folder within the "QTs"" desktop folder has a modification date and time stamp greater than 15 minutes old, it is assumed that no further CT or MR slices will be added to that particular folder because such files are usually sent from the DICOM appliance in rapid sequence.
If a matching inpatient medical record number can be found on the "OrthoMac" server, Hypercard rewrites the "QTList" text file within the "QTs" desktop folder to include all return-delimited paths of all files within the JPEG slices folder (e.g. CTP4251435 - i.e.)
Hypercard activates a "Debabelizer" Batch Mode "jpgmov" script which uses the "QTList" text file to sequentially select JPEG slices and combine them into a QuickTime Movie file (qt.mov) format. The usual settings are flattened CinePak, 256 grays, 2 frames/second. The completed Quicktime CT Or MR movie is then renamed and copied to the "OrthoMac:Trauma Register:JPGA" archive folder where it is hyperlinked to OrthoMac's Hypercard INPT stack, the "trdb.dbf" Fox Pro database and the FileMaker Pro web-served "ortx.fp3" database is the same manner described for xrays.
Subfolders and qt.mov's of DicomSrv "QTs" desktop folder not matched with inpatient records within 48 hours are deleted.