1991, The British Journal of Radiology, 64, 461-462
Technical note Fast personal computer based retrieval system for a high-volume database of a radiology information system By *Reinhard Urhahn, PhD and Rolf W. Giinther, MD Department of Diagnostic Radiology, Technical University of Aachen, Pauwelsstrasse W-5100 Aachen FRG (Received April 1990 and in revised form August 1990) Keywords: Personal computer, Database retrieval, Radiology information system
Abstract. A personal computer system has been used to facilitate search and analysis of a radiology information system database (RADOS) for research purposes. The system enables flexible retrieval of examination data and radiographic findings with subsequent graphical manipulations. With modifications it could be implemented on other radiology information systems.
A growing number of radiology departments today use commercially available computerized radiology information systems (RIS) for departmental management. They are designed to manage such functions as patient registration, examination scheduling or diagnostic reporting. In addition, some systems support retrieval functions for research purposes. However, the retrieval software is often insufficiently adapted to the specific needs of the user. For example, graphical representation of retrieved data is not possible. Because of increased demand for medical database retrieval we linked a personal computer (PC) to our department's RIS (RADOS) and developed appropriate software for the transfer and analysis of selected examination data. Our objective was to facilitate both database search and manipulation of retrieved information. The system design and performance are the subject of this article. Methods
The RIS installed is an information system (RADOS, Philips) based on a Micro VAX II computer, used to manage about 130000 examinations annually. The PC is a commercially available microcomputer system (Atari 1040STF) including a hard disk and a high-resolution graphic monitor. At present the PC is connected with the VAX via an RS232C interface with a maximum data transfer rate of 19200 Baud. A high-speed Ethernet network will be available for the PC in the near future. Data transfer is performed by PC resident I/O routines activating VAX resident standard functions of the RADOS archive menu to collect and transmit selected data. The menu-driven PC software (compiled in BASIC) comprises the following procedures: (a) Transfer/sort, (b) pre-scan and (c) main-scan.
*Author for correspondence. Vol. 64, No. 761
Transfer/sort This procedure creates a stand-alone database on the PC. The following basic patient and examination data of the RIS database are used: examination type and identification number, age and sex of the patient, referring clinical department and report status. The basic data are usually transferred quarterly from the RIS to the PC. After subsequent sorting by examination type they are stored in a random access file on the hard disk. An additional index file enables fast data access. Pre-scan This performs a search of the PC database, starting up with the input of the parameters "examination year(s)" and "examination type or group". Search restrictions to age groups, patient sex or referring departments are possible. The procedure generates a sorted list of the specified examinations and corresponding basic data of the PC database with additional statistics and diagrams (e.g. age distributions). All results may be hardcopied or graphically represented on the screen. On request the selected examination identification numbers are stored for later retrieval of radiographic findings. Main-scan This procedure enables retrieval of radiographic findings. Having transferred the pre-selected identification numbers to the VAX, the procedure receives corresponding basic demographic patient data and the data records for the free report text, clinical details and numeric codes for radiographic findings similar to the ACR code (American College of Radiology, 1975). During the transmission the data records are simultaneously checked for selected keywords and code numbers. The matching records are printed out or stored on disk in a standardized format for further analysis and manipulations such as individual graphical representation and establishment of teaching-file databases. 461
Reinhard Urhahn and Rolf W. Giinther
year:1988 exan:CHEST departnent(s): ALL
0
age:8-100
n=2686i nale=15090 fenale=ii77i
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 [y]
Figure 1. Graphical analysis of selected examination data: frequency of standard chest radiographs (%) versus patient age. Results
The retrieval system has been in operation for 1 year. Typical execution times are transfer/sort 20 minutes (quarterly), pre-scan 5 seconds (search volume 1 year), main-scan 15 minutes (search volume 1 year). Typical examples of application are shown in Fig. 1 and Table I. Figure 1 shows the frequency of chest radiographs versus patient age. In addition, the diagram shows the overall (inset) and age-dependent frequency for female (white lines) and male patients (black lines). The characteristics of the distribution depend on the morbidity and the demographic structure of the local population as well as on the clinical disciplines. The analysis of such distributions may be useful for the estimate of age-dependent radiation exposure. The result of an analysis of radiographic findings is given in Table I. The free text of chest radiograph reports was searched for keywords such as "azygos lobe" or portions of the keyword with regard to typing errors. The overall incidence found for the azygos lobe agrees with the literature (Felson, 1973). Discussion Personal computers are useful for database management in an academic radiology environment (Kurtz et Table I. Incidence of the accessory lobe of the azygos vein, keyword "azygos lobe" (1988-June 1989, standard chest examination)
Individuals Azygos lobe Incidence (%)
462
Female
Male
Total
10087 40 0.40
11752 67 0.57
21839 107 0.49
al, 1984; Sommer, 1986; Amis, 1987). The described PC-based retrieval system is a powerful low-cost supplement to a high-volume RIS, relieving the main computer of time-consuming search operations. The developed software allows fast transfer, analysis and graphical manipulation of examination data. Flexible retrieval of radiographicfindingsis performed by a code and keyword-based procedure including both search of free text and diagnosis code. The system could serve as a model for radiology departments equipped with information computers insufficiently provided with flexible retrieval software for research as well as clinical service. Unfortunately, most RIS systems use different standards for patient and examination data access and data format. Implementation of the system on a different RIS therefore requires some modifications of the data aquisition routines of the PC software. Technical details and programme source code are available from the authors on request. References American College of Radiology, 1975. Index for Roentgen Diagnosis, 3rd edn. (American College of Radiology, Chicago, IL). AMIS, E. S., 1987. Microcomputer applications for the academic radiologist. American Journal of Roentgenology, 149, 187-190. FELSON, B., 1973. Chest Roentgenology (Saunders, Philadelphia, PA) pp. 74-77. KURTZ, D., HELFGOTT, R., HILL, S. C , KRUDY, A. G., MILLER,
D. L. & MORRISH, K. A., 1984. Use of a microcomputer to
store information on radiology cases. British Journal of Radiology, 57, 1097-1102. SOMMER, F. G., 1986. Some applications for a personal computer database system in radiology. American Journal of Roentgenology, 147, 1075-1077. The British Journal of Radiology, May 1991
Technical note Fast personal computer based retrieval system for a high-volume database of a radiology information system By *Reinhard Urhahn, PhD and Rolf W. Giinther, MD Department of Diagnostic Radiology, Technical University of Aachen, Pauwelsstrasse W-5100 Aachen FRG (Received April 1990 and in revised form August 1990) Keywords: Personal computer, Database retrieval, Radiology information system
Abstract. A personal computer system has been used to facilitate search and analysis of a radiology information system database (RADOS) for research purposes. The system enables flexible retrieval of examination data and radiographic findings with subsequent graphical manipulations. With modifications it could be implemented on other radiology information systems.
A growing number of radiology departments today use commercially available computerized radiology information systems (RIS) for departmental management. They are designed to manage such functions as patient registration, examination scheduling or diagnostic reporting. In addition, some systems support retrieval functions for research purposes. However, the retrieval software is often insufficiently adapted to the specific needs of the user. For example, graphical representation of retrieved data is not possible. Because of increased demand for medical database retrieval we linked a personal computer (PC) to our department's RIS (RADOS) and developed appropriate software for the transfer and analysis of selected examination data. Our objective was to facilitate both database search and manipulation of retrieved information. The system design and performance are the subject of this article. Methods
The RIS installed is an information system (RADOS, Philips) based on a Micro VAX II computer, used to manage about 130000 examinations annually. The PC is a commercially available microcomputer system (Atari 1040STF) including a hard disk and a high-resolution graphic monitor. At present the PC is connected with the VAX via an RS232C interface with a maximum data transfer rate of 19200 Baud. A high-speed Ethernet network will be available for the PC in the near future. Data transfer is performed by PC resident I/O routines activating VAX resident standard functions of the RADOS archive menu to collect and transmit selected data. The menu-driven PC software (compiled in BASIC) comprises the following procedures: (a) Transfer/sort, (b) pre-scan and (c) main-scan.
*Author for correspondence. Vol. 64, No. 761
Transfer/sort This procedure creates a stand-alone database on the PC. The following basic patient and examination data of the RIS database are used: examination type and identification number, age and sex of the patient, referring clinical department and report status. The basic data are usually transferred quarterly from the RIS to the PC. After subsequent sorting by examination type they are stored in a random access file on the hard disk. An additional index file enables fast data access. Pre-scan This performs a search of the PC database, starting up with the input of the parameters "examination year(s)" and "examination type or group". Search restrictions to age groups, patient sex or referring departments are possible. The procedure generates a sorted list of the specified examinations and corresponding basic data of the PC database with additional statistics and diagrams (e.g. age distributions). All results may be hardcopied or graphically represented on the screen. On request the selected examination identification numbers are stored for later retrieval of radiographic findings. Main-scan This procedure enables retrieval of radiographic findings. Having transferred the pre-selected identification numbers to the VAX, the procedure receives corresponding basic demographic patient data and the data records for the free report text, clinical details and numeric codes for radiographic findings similar to the ACR code (American College of Radiology, 1975). During the transmission the data records are simultaneously checked for selected keywords and code numbers. The matching records are printed out or stored on disk in a standardized format for further analysis and manipulations such as individual graphical representation and establishment of teaching-file databases. 461
Reinhard Urhahn and Rolf W. Giinther
year:1988 exan:CHEST departnent(s): ALL
0
age:8-100
n=2686i nale=15090 fenale=ii77i
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 [y]
Figure 1. Graphical analysis of selected examination data: frequency of standard chest radiographs (%) versus patient age. Results
The retrieval system has been in operation for 1 year. Typical execution times are transfer/sort 20 minutes (quarterly), pre-scan 5 seconds (search volume 1 year), main-scan 15 minutes (search volume 1 year). Typical examples of application are shown in Fig. 1 and Table I. Figure 1 shows the frequency of chest radiographs versus patient age. In addition, the diagram shows the overall (inset) and age-dependent frequency for female (white lines) and male patients (black lines). The characteristics of the distribution depend on the morbidity and the demographic structure of the local population as well as on the clinical disciplines. The analysis of such distributions may be useful for the estimate of age-dependent radiation exposure. The result of an analysis of radiographic findings is given in Table I. The free text of chest radiograph reports was searched for keywords such as "azygos lobe" or portions of the keyword with regard to typing errors. The overall incidence found for the azygos lobe agrees with the literature (Felson, 1973). Discussion Personal computers are useful for database management in an academic radiology environment (Kurtz et Table I. Incidence of the accessory lobe of the azygos vein, keyword "azygos lobe" (1988-June 1989, standard chest examination)
Individuals Azygos lobe Incidence (%)
462
Female
Male
Total
10087 40 0.40
11752 67 0.57
21839 107 0.49
al, 1984; Sommer, 1986; Amis, 1987). The described PC-based retrieval system is a powerful low-cost supplement to a high-volume RIS, relieving the main computer of time-consuming search operations. The developed software allows fast transfer, analysis and graphical manipulation of examination data. Flexible retrieval of radiographicfindingsis performed by a code and keyword-based procedure including both search of free text and diagnosis code. The system could serve as a model for radiology departments equipped with information computers insufficiently provided with flexible retrieval software for research as well as clinical service. Unfortunately, most RIS systems use different standards for patient and examination data access and data format. Implementation of the system on a different RIS therefore requires some modifications of the data aquisition routines of the PC software. Technical details and programme source code are available from the authors on request. References American College of Radiology, 1975. Index for Roentgen Diagnosis, 3rd edn. (American College of Radiology, Chicago, IL). AMIS, E. S., 1987. Microcomputer applications for the academic radiologist. American Journal of Roentgenology, 149, 187-190. FELSON, B., 1973. Chest Roentgenology (Saunders, Philadelphia, PA) pp. 74-77. KURTZ, D., HELFGOTT, R., HILL, S. C , KRUDY, A. G., MILLER,
D. L. & MORRISH, K. A., 1984. Use of a microcomputer to
store information on radiology cases. British Journal of Radiology, 57, 1097-1102. SOMMER, F. G., 1986. Some applications for a personal computer database system in radiology. American Journal of Roentgenology, 147, 1075-1077. The British Journal of Radiology, May 1991
