1. Field of the Invention
This invention relates to an image filing apparatus wherein image signals, which represent images, and subsidiary information belonging to each of the images are stored on an optical disk, an image signal retrieving data base is constructed from the subsidiary information such that an image signal corresponding to the subsidiary information may be retrieved, and the image signal retrieving data base is used during the retrieval of the image signals.
2. Description of the Prior Art
Image filing apparatuses for filing image signals, which represent images, have heretofore been used in various fields. For example, at medical facilities, such as hospitals, many kinds of medical images are utilized for medical treatment or research. Most of the medical images are radiation images. In recent years, many computed tomography (CT) images, magnetic resonance (MR) images, and the like, are also utilized.
The medical images should be stored to permit investigation of changes in diseases or injuries of patients, and it is legally stipulated that the medical images must be stored for a predetermined period. Therefore, in hospitals, or the like, the number of stored medical images increases daily. The medical images have heretofore been stored in the form of hard copies. However, storage as hard copies requires a large storage space and burdensome operations for control and retrieval of the medical images in hospitals, or the like.
Accordingly, in recent years, an image filing apparatus has been proposed in which images, such as medical images, are retrievably stored (i.e. filed) as image signals on a storage medium. In cases where the medical images are filed in this manner on the storage medium, the space requirement and the burden of image storage can be reduced, and the images can be retrieved easily and quickly.
In the image filing apparatus for filing the image signals in the manner described above, a data base is constructed from subsidiary information corresponding to each of the image signals and is used during the retrieval of the image signals.
In general, image signals are detected automatically when images are read out with an image read-out apparatus, or the like. On the other hand, subsidiary information is ordinarily entered from, for example, a keyboard each time the corresponding image is recorded on a recording medium. In cases where the image is a medical radiation image of a patient, the subsidiary information includes, for example, the name of the patient recorded, the date on which the image was recorded, the name of the image recording apparatus which was used to record the image, the portion of a patient the image of which was recorded (e.g., the head, the chest, or the abdomen), and the mode which was used when the image was recorded (e.g., an ordinary image recording mode, an enlarged image recording mode, or a tomography mode). When the subsidiary information is entered from a keyboard, or the like, it often occurs that incorrect subsidiary information is entered by mistake. In such cases, the incorrect subsidiary information is stored on an optical disk together with the corresponding image signal. Also, a data base is constructed from the incorrect subsidiary information.
Even if incorrect subsidiary information is entered, no serious problem will occur when it is stored on an optical disk. However, a serious problem will often occur when a data base is constructed. For example, if an unexpected value (e.g. 1800) is entered as the date on which the image was recorded, normal regions of the data base will be destroyed, and it will become impossible for image signals corresponding to normal subsidiary information to be retrieved.
In order for the aforesaid problems to be eliminated, it will be considered to provide a means for preventing a data base corresponding to normal subsidiary information from being destroyed. However, in such cases, problems occur in that an incorrect data base is constructed from incorrect subsidiary information, and in that an image signal corresponding to the incorrect subsidiary information cannot be retrieved.