1. Field of Invention
This invention relates to an X-ray computerized tomograph (hereinafter called "X-ray CT"), and more particularly to an operator console for inputting scanning conditions of the X-ray CT.
2. Description of Prior Art
Computerized tomographs are known in the art, which emit an X-ray beam at a number of angles in a plane across a subject or a patient, and determine a distribution of X-ray absorptivities of various body sections, and display the absorptivity distribution on a screen of a display unit.
FIGS. 1 1(A) (B), and 1(C) depict the main components of a general X-ray CT. FIG. 1(A) illustrates a scanning gantry 1 and a patient table 2. Scanning gantry 1 has therein an X-ray tube and an X-ray detecting device (not shown) which are disposed in confronting relation to each other across an opening. Table 2 includes a cradle 4 axially slidable forward into opening 3, or backward out of opening 3, while carrying a subject or a patient (not shown) thereon, for exposure to the X-ray in gantry 1.
FIG. 1(B) shows a computer for controlling the overall X-ray CT and effecting computations for image reconstruction, for example.
FIG. 1(C) depicts an operator console having a variety of switches disposed on a panel thereof and selectively actuable for scanning operation of the X-ray CT, and a cathode ray tube 5 (hereinafter called "CRT").
In operating the X-ray CT of the above configuration, pieces of information, such as scanning conditions, are inputted normally through scanning operation on the operator console. Methods of entering such information include (1) a conversation or interactive process using a keyboard on the operator console while watching messages displayed on the CRT of the console; and (2) process of selectively actuating the switches on the panel of the console.
Method (1) is , however, disadvantageous, in that the operator must become experienced in keyboarding. It takes time to master operation of the CT. Numerous erroneous control operations tend to occur, since the operator is required to do the keyboarding while looking at the messages on the CRT.
Method (2) has a problem, in that, that the switches cannot be properly actuated unless the operator knows the correct switching operating sequence.
The scanning of the X-ray CT comprise such conditions as field of view (FOV), scanning time, current to flow through the X-ray tube for generating an X-ray, slicing interval, thickness to be sliced, and other parameters. In known CTs, (a) scan parameters are set while watching messages displayed on the CRT in a conversation or interactive process, or (b) scan parameters are selected and set by various selecting and setting switches on the panel each time the patients are changed or scan parameters are changed. Once an anatomy section to be scanned has been determined, a predetermined combination of scanning conditions or parameters, which are tailored to a particular hospital, is usually available for most of the scans thereat. However, with the above processes (a) and (b), scan parameters have to be established in each scanning operation, even when scanning is to be effected under routine conditions. Thus, prior parameter setting has been tedious and time consuming.