FR2892551A1 - Object or subject`s radiographic or fluoroscopic image identifying method for use in e.g. medical radiology, involves decoding image from label, finding data indexed relative to object and counter-marking film by printed paper label - Google Patents

Abstract

The method involves forming a temporary marking tag label matrix coded by local variations in thickness. The label is fabricated by perforating a radiation absorbing band or depositing material on a label support absorbing less radiations. The label is affixed on a radiographic film cassette or image receiver. The label is removed from a management identifier and indexed with a data from an object in a radiological information system. An image from the label is decoded and the data indexed relative to the object is found. A film is counter-marked by a printed paper label carrying marking data. Independent claims are also included for the following: (1) a system for implementing a method for identifying a radiographic or fluoroscopic image of an examined object or cassette (2) a radiography or fluoroscopic image marking label obtained by a method for identifying a radiographic or fluoroscopic image of an examined object or cassette (3) a radiographic film cassette.

Description

The present invention relates to conventional radiography on film,

  in the industrial field as in the medical field, but it also applies to fluoroscopy. It consists of an automated method and means for the corresponding implementation, for the identification of radiographic or radioscopic images of a subject or object under examination. This identification is indispensable in order to assign for sure the diagnosis of this examination to the subject or to the object under consideration; for this purpose, the radiographic or radioscopic images must include identifying marks, making it possible to put a single link between the subject or object under examination and its radiographic or radioscopic image.

  The image receptors used were, first of all, silver films which are still very much used in industry and in so-called conventional medical radiology, then image intensifiers and scintillator screens, which are associated with a camera. Linear detectors and planar detectors, appeared more recently, they provide, directly or indirectly, a scanned image.

  Whatever the image receiver used, the essential requirement of identification must be satisfied; the identification data concern the identity of the subject or the object, the date, but they also relate to the exposure or relative orientation between the subject or the object and the detector, the eventual case on the lot number or in series and sometimes on other additional data, such as the references of the procedure followed for the acquisition of the radiographic or radioscopic image, the references of the document defining the acceptance criteria or the criteria for the notation of the indications seen on radiographic or radioscopic images, other data defined by the user. In common use, it is considered that the radiological image must contain these data in a positive and self-supporting way, so that the radiologist can confidently assign the images, which he interprets, to the subject or object concerned. this without having to find these data by a search, or by an external request, nor to deduce them in any way. However, the identification of the object or subject is also achieved by assigning to each image a management identifier, preestablished, unique, non-significant vis-à-vis the object or subject, but which one uniquely matches all previous identification data. The management of identifiers and correspondence is easy to ensure, especially through links and computer tools, spreadsheet or database. This practice makes it possible to shorten the length of the identifier, it is simpler to implement in an entity having a radiology information system, but in any case it is generalizable thanks to remote access means such as Internet. The structure of the identifier can be customized to an entity, a company, a constructor or can be summed up to a serial number in particular series; the need for standardization is lower here than in industrial or consumer products, because radiographic images circulate less than these products; in fact they are handed over either to the subject or to the owner of the object or else they are kept by the manufacturer. In film radiography, an industry-proven method is to use materials that are opaque to ionizing radiation, such as lead for marking the radiological image. Typically, letters and lead figures of appropriate size are placed as in a typographic composition directly on the object itself or on the image receptor, and are held there by an adhesive. An alternative is to use a support strip mutual hold letters and numbers, said strip being placed on the object or when and possible on the receiver. By its manual character, this identification process is slow, and the time required for this can be long compared to the exposure time for the acquisition of the radiological image, on the other hand it includes risks of misreporting. In other circumstances, in particular, in situ, as in industrial installations, the working environment may make the marking composition more difficult because of the wearing of personal protectors such as gloves, and may lead to loss of letters. or figures, when placing or removing the marking. Moreover, the extended time for this marking can expose the speakers to various nuisances. The volume of the identification data can be extended, the time required for the corresponding composition is increased. Sometimes it is the size of the area allocated to marking that is either excessive or limited, its smallness then posing operational difficulties of marking. Another method of marking, used more often in the medical than in the industry, is to mark the film, using a system of light marking, or an identification camera. By this method, the marking is therefore done outside the radiological exposure phase, either before or after, requiring ordered manipulation of the cassettes. The placement in the scene of identification markers, during the exhibition so that they are projected onto the image remains the most reliable identification procedure, which is why it remains very used in film radiography. the luminous marking is badly accepted, if not proscribed, in the industry because of its poor legibility and the risks of confusion in the handling of cassettes.

  In radiology using receivers such as image intensifiers or scintillator screens, it is also possible to use markers of letters and numbers of lead, or other markers producing the same effect. When the image is directly scanned, then the previously entered identification data is embedded in a specific field of the image file, according to standardized or standardized provisions, such as those of DICOM. The photostimulable plate receivers provide a scanned image but require, after exposure, to be read on a laser bench to restore the latent image, however the identification data are recorded during the acquisition and then they are incorporated into the image file. picture as before. These means of direct or indirect digitized radiology are expensive, and therefore their use is not yet generalized; moreover, these means are generally fixed, which restricts their use as ambulatory or in situ. The purpose of the present invention is to provide users of conventional radiography on film and of radioscopy, of the industrial field and of the medical field, a set of methods and means for its implementation, which makes it possible to automate , the marking by an identifier for the identification of the radiographic or radioscopic images, the reading of this identifier and the counter-marking in clear of the film. This automation brings gains in speed and productivity as well as reliability gains, and also opens the door to greater automation in interpretation support and reporting support. The invention aims to replace the method of marking or identification by letters and / or figures in lead, or any equivalent marking mode, but also the light marking, which is particularly poorly accepted in the industry.

  The method of the invention consists of an automated method for marking the X-ray film of the subject or object under examination, using in a known manner the following means: a coded label, like the matrix code labels, carrying a management identifier to mark the object as well as its x-ray image * an optical system for reading and decoding on the one hand the label, and on the other hand its radiographic image, a system communicating with the information system an information system of the radiology entity considered, for managing and mapping by tables and databases, the data of the identifier of each radiographic image with the data previously entered, relating to the identification; of the subject or object and the exposure considered * a self-adhesive label to counter-mark the radiographic film in clear, data relating to the identification of the object t or the subject and its radiographic exposure, label edited by a label printer characterized by the following successive phases: a) -design of a label receiving the data of a management identifier, arbitrary but unique for each label in a matrix-encoded form by visible and readable local label thickness variations determined to produce corresponding visible and readable X-ray-induced radiation absorption variations on the X-ray images of the label, and distributed in an organized manner on the label area b) - creation of a label, assigned a management identifier, digitized and coded by local variations of thickness defined and organized on the area of the label thickness variations in sub-thickness, or extra thickness, of a color contrasting with the bottom of the label to allow an optical reading of the label c) - marking by affixing the coded label, either on the film cassette or on the image receptor on the side of the radiation input face, or on the face of the object on the output side of the radiation, in order to maximize the contrast and sharpness relative to the thickness variations of the label d) - reading of the marking of the cassette or the object, for each radiographic exposure, by an optical system ensuring the reading and the decoding of the label and addressing the data of the identifier of the tag, to a database of the information system of the radiology entity, with indexing between these data and the previously loaded data, relating to the identification of the object or subject and those of the radiographic exposure e) - reading of the radiographic image of the label on the exposed and developed film, in combination with a negatoscope, then decoding of the identifier of the label, gr this to the optical system communicating with the information system, where restitution of the correspondence between the identifier of the label and the identification data of the subject or object, with clear display of these data to the position interpretation of the radiologist, and digital recovery for assistance in interpreting and preparing the test report f) - counter-marking the film with a new printed label, edited by a label printer driven by the information system, label, preferably self-adhesive, bearing in clear all the returned data of the identification of the object or subject, the radiographic exposure and the marking mark data, all previously associated data to the coded label The phases of the method previously identified from a) to f) can be supported and implemented by the user, that is to say the medical radiology or undue service. strielle. Moreover, by the method of the invention, the marking data of the film could be entirely coded on the label, but in a preferred embodiment of the invention, the labels carry a coded management identifier, arbitrary and unique, and they are prefabricated and provided to the user. The marking of the subject or the object is thus obtained by assigning each radiographic image a management identifier to each radiographic image; this management identifier is mapped to all the data relating to the identification of the subject or object, as well as to the radiographic exposure considered by means of an information system of the radiology entity and to means such as an optical reader, so that the recognition of the identifier can automatically bring back the recorded data of the identity of the object and those of its exposure. This design of the marking by a management identifier makes it possible: to limit the length of the marking, to perform a low density matrix coding, to predefine and to prefabricate the labels before their use and thus to supply the user with consumable labels, at a marginal marginal cost. The film being finally counter-marked, by a paper label clearly indicating all the expected or specified data relating to the identification of the subject or the object, the identifier has no place to be read or understood by the final recipient of the film. In the invention, the marking by the label applied on the cassette or on the object is temporary, because the film is finally countermarked by a self-adhesive paper label, which in clear all the identification data of the subject or the object, exhibition and benchmarks for the film. This property of the invention allows the reuse of the same label during different work sessions, since the counter-marking of the film is done in a session including: marking, exposure and counter-marking. Moreover, the information system allows, if the same label is used a second time, to ensure that the counter-marking following the first use has been made. Thus, the radiology entity or service, obtains a few batches of reusable labels, the labels being all different from one another, and allocates a lot of labels in sufficient number to cover the needs of marking the films in a working session, the session being half a day, the day or a set of days given.

  The following work session, a past session is therefore with a lot of labels separate from the one used in the previous session. When several teams of radiologist operators or manipulators work in the same work session, they each receive a lot of labels. The first phase of the method of the invention, identified a), consists in designing a label on which the data of a management identifier are coded, this by local variations in thickness inducing a visible and readable contrast on the one hand on the label and on the radiographic image of the label. The design therefore relates to the code or language convention that governs the arrangement of the aforementioned thickness variations on the area of the label and the corresponding meaning. The coding is binary in that each cell of the matrix of the label takes two different values depending on whether the cell in question is the seat, or not, of a variation in thickness. The use of a standard matrix coding: Datamatrix, maxicode, PDF 417 can be considered but their density is too high, taking into account the intended embodiment of the label. Moreover, the detection on the radiographic image of the variations of thicknesses of small section is not assured. Therefore, in the invention, the coding of the management identifier is a low density matrix coding, obtained by the single distribution specific to each label, of a given number of thickness variations on the zone of marking of the label considered divided into meshes or fictitious, regular, square or rectangular cells. The thickness variations are then arranged substantially in the center of a few meshes, in a manner similar to a check grid. The identifier is thus characterized by a numerical value or proper and distinctive attribute, composed from the rank or order number or from the orthogonal coordinates of the centers of the marked stitches. The given number of thickness variations defining an identifier, associated with the total number of meshes in the tagging area of the tag determines the total number of distinct tag issuing possibilities. The given number of thickness variations on the one hand, and the number of meshes on the other hand, are all the higher if a continuous and absolute list of marks is desired. In one embodiment of the invention, this number of variations in thickness is between three and eight because it makes a compromise between the number of possible cases and the manufacturing time of the label. Also still in the invention, a variation of thickness additional to those of the identifier of the label is created to constitute the control key of the coding. Still in the invention, the local thickness variations are designed and made in two distinct modes: on the one hand in extra thickness, on the other hand in sub-thickness. The variation in under-thickness is obtained by the perforation through a label absorbing radiation well due to its nature and its thickness. The variation in extra thickness is obtained by depositing pellets, of a nature and a thickness that absorbs radiation well, on a label carrier, itself not very absorbent. This design step aims to define, also by calculation but also by experience, the nature of the material to be used to achieve the variations in thickness, as well as the dimensions of these variations: section and height to obtain the contrast on the radiological image, the height being taken in a direction perpendicular to the face of the label; the high atomic number materials are well suited to the constitution of thickness variations.

  In the invention, in addition to the perforations or pellets constituting the codification of the management identifier, additional perforations or deposits of the label, in number preferably between three and six, are arranged on the periphery of the container. asymmetrically and at known mutual distances to serve as control points when reading the label and its radiographic image thereby ensuring image orientation registration and delimitation of the perimeter of the area marking. These control points make it possible to determine the direction and the orientation of the label, and if necessary to carry out a registration by the calculation thanks to translations, rotations, symmetries and also to define the useful zone of the image during the decoding. They are also used to determine the coordinate reference of the perforations or pellets on the label image and on the radiographic image of the label. The coding of the label is obtained by local variations in the thickness of the label, preferably in the form of a circular section or in a regular polygonal shape with an area equivalent to the circular shape, in order to facilitate their automatic detection on the label. radiographic image. Local variations in the thickness of the label or material placed on the label are determined to cause some radiation absorption and to induce on the X-ray image a contrast necessary and sufficient for detection and reading. automatic. The creation of the contrast between the radiological images of the local variations of thickness and the zones surrounding these images, results from the combination of several factors, the principal ones of which are: the nature and the thickness of the material in which these variations of thickness, energy of the radiations used: voltage of station X or radioelement used in the industrial radiography, the detectors used: type of films and screens, the conditions of exposure of the stage, the conditions of development, the resolution and the sensitivity of the reading means of the radiological image of the label. The thickness variation section of the label should not be below a minimum otherwise their X-ray or X-ray images may either be less contrasty due to geometric blur or poorly detected due to resolution and the sensitivity on the one hand of the image receiver and on the other hand the image reading means; conversely, excessive sectioning unnecessarily increases the label dimensions. A balance is thus to be found for a user, either by experience or by calculation. For common X-ray applications, the diameter of the perforations or pellet is between 0.5 and 3 millimeters. The thickness variations are defined and organized on the label so as not to be intersecting with each other; in general, the value of the isthmus or ligament between two adjacent thickness variations, in the two directions of the label, is substantially equal to the value of the diameter, the center distance thus being equal to two diameters. But this value of isthmus is optimized by experience or by numerical simulation. In general, the highest thickness variations of a given material produce the strongest contrasts on the radiographic or radioscopic image. Moreover, for a given thickness variation, the contrast on the image is all the more important that the material used has a high coefficient of absorption of ionizing radiation and vice versa. Lead and its alloys have a remarkable power of absorption, hence their well-known use in radioprotection and in the marking of radiographic or radioscopic images, as recalled in connection with the above-mentioned letters and figures. But all materials absorb ionizing radiation, very unevenly and they are potentially more or less suitable for the present use. Thickness variations of the label identifier are correlated to the diameter of the perforations or pellets, to induce readability on the radiographic image, as is the case in some image quality indicators. Moreover, the readability of the radiographic image of the label is also linked to the quality index of the radiographic image. This quality index is set a priori at a given level, and subsequently it is found and evaluated by an image quality indicator. The image quality indicators are generally standardized, among them the wire indicators and the perforated penetrammeters. The perforated penetrameter is a piece of the same absorption characteristic as the subject or object to be examined, it comprises bearings of different thicknesses, in which holes of different diameters are made. The rating of the image quality index is based on the smallest holes visible on the radiographic image; in general the diameter of the holes is directly related to the thickness of the bearing considered and in some standards the value of the diameter is the thickness of the bearing. In industry, the image quality index is set to different values, depending on the codes and specifications applicable to an object; thus for a given radiographic examination to be performed, the radiologist knows the value of the image quality index to be achieved and must take this into account in the choice of the operating mode. In the invention, the readability on the radiographic image of the perforations or overthicknesses of a given label for the examination of a subject or an object under defined operating conditions, of course derives from the label itself. but also the quality or sensitivity of the radiographic image. This is why the user can choose the type of label for a radiographic control depending on the thickness to cross therefore the radiation energy and the target image quality index. The material constituting the variations in the thickness of the label, which bear the coded information of the identifier, must be determined during the design taking into account the conditions of implementation of the radiography. This determination is made by calculation, but it is accessible through experience. In the invention, the placement of the label in contact with the cassette or on the object, the output side of the radiation, is conducive to obtaining a maximum contrast for a given label. This is why the thickness variations of the label, which cover the vast majority of the requirements, are 0.1 to 0.5 millimeters when they are made of lead and 0.2 to 2 millimeters for metals: copper, steel, aluminum. If necessary, thicknesses greater than 2 millimeters can be envisaged, but a superposition on the one hand of lead and on the other hand of one of the aforementioned metals is another possible solution of realization. As an indication, the ratio between the diameter of the perforations or that of the pellets and the variation in thickness is between 1 and 2. The format of the labels stems, to a good extent, from the value of the diameter of the thickness variations selected. if you want to get enough labels whose code is unique. On the other hand, since the label must be readable by the optical reader, the color of the label background and that of the thickness variations must be chosen to be contrasted to ensure a reliable reading.

  The method of the invention uses the information system of the radiology department, however access to this information system is not always easy, or simply possible, as in the outpatient practice, in medicine but especially in the field. during inspections of industrial plants under construction or maintenance. Therefore, in the invention, a variant of the design and manufacture of the label consists in producing a multilayer label; this so-called motherboard label comprises different self-adhesive multilayers, the coding of which, preferably, by perforations then replicates the data on each layer. In one embodiment, the motherboard is a two-layer and thus made on the one hand of a radiation absorbing layer for marking the cassette or the object, and on the other hand a layer paper or plastic film to be affixed to a support, such as the tracking document of the object in order to transfer the marking data of the object and those of its radiographic image.

  The separation of the 2 layers of the labelimmer once perforated, in 2 labels with identical content, thus allows: - to mark the object and thus its radiographic or radioscopic image - to postpone in a certain and fast manner, this marking on a document tracking the object, which is replayed offline by the optical drive.

  The color of the layers is chosen according to the color respectively of the object and that of the document on which it must be affixed for the marking report, in order to provide a sufficient contrast between label and perforation, capable of guaranteeing an optical reading. . The marking survey phase marked d) is thus done after returning to the radiology department, by reading the tracking sheet completed with duplicate labels. The film cassettes used by medical or industrial radiography professionals are two types: on the one hand the rigid cassette, usually made of aluminum, on the other hand the flexible plastic cassette, this flexible cassette being either reusable or consumable. The label provided for in the invention is affixed to the cassette or the object; thus the label provided for a flexible cassette should preferably be itself flexible, although the use of a rigid label on a flexible cassette is possible. A label affixed to an industrial object must be flexible to conform to the part of the object, which is not always flat. On a rigid cassette, the rigid label and the flexible label are both usable. In addition, the label must be kept on the cassette or on the object; to this end, in the invention, the label is either self-adhesive or inserted into a small case attached to the cassette. A rigid label, not self-adhesive, is reusable many times, however a self-adhesive label can be affixed-filed, a limited number of times. For industrial applications, a flexible label, non-self-adhesive and reusable, is also a design option, the label being held on the object by a strip of adhesive overlapping the label. The self-adhesive label, used once, is another option of the invention, since its cost to the user is acceptable. For a consumable cassette, that is to say flexible and delivered loaded with its film and its possible screens, preference is given in the invention to a label itself consumable. The second phase of the method of the invention, identified b) consists in manufacturing the marking label. The requirements for the definition of the label provided for in the invention are multiple and they lead to many design choices, among which are described below two preferred embodiments. One embodiment of the label is that of the rigid label, hereinafter described the label intended for application on a rigid cassette and for repeated uses. The label is obtained very simply from a metal plate of rectangular format, length between 20 and 75 millimeters, for a width ranging from 10 to 25 millimeters. The constituent material of this wafer is: steel, copper or alloys of these metals; aluminum is another possibility. Copper is a suitable material for its rather high absorption properties. The thickness of this wafer is between 0.2 and 2 millimeters, the choice of the thickness of the label for a given user operates according to the energy of the radiation used. This plate is perforated or pierced with circular holes, the smallest holes corresponding to the smallest label sizes, for example with a diameter of 1 millimeter for small label sizes, of the order of 10 by 25 millimeters and of submillimeter thickness, with a diameter of 2 millimeters for a double format with a thickness of between 1 and 2 millimeters. Diameters of 3 millimeters lead to larger label sizes, but the need for labels of this diameter is, in fact, infrequent. The coordinates of the centers of holes practiced then constitute a data set characteristic of the management identifier of this label. The code corresponds to a given number of holes, preferably between 3 and 8; an additional hole is provided for a control key determined during the coding. Note that the application of this label on a rigid cassette allows the use of a label of higher thickness when the environment of the cassette does not set a physical limit. The marking area of the identifier on the label excludes the periphery thereof; furthermore outside this marking area of the identifier, additional holes are made at known and constant coordinates for a label format to constitute control points. The board 1/4 illustrates a rigid label model, as described above, Figure 1 gives a plan view of the label, while Figure 2 corresponds to a longitudinal sectional view of the label by parallel plans. The drawing of Figure 1 is scale 1 of the label, the approximate dimensions are therefore, length: 68 millimeters, width: 30milimeters, but often labels of a smaller size than indicated by this drawing in a homothetic ratio of 2/3 leading to dimensions of 45 mm by 20 mm will fit the needs of most users. Even smaller sizes are possible, but larger ones may be needed when the definition leads to high hole diameters greater than 3 millimeters. In FIG. 1 of the plate 1/4, the body of the label is marked (1), the coding holes of the identifier of the label are marked (2), including the control key, while the holes of the control points are marked (3). A lacquered paint is applied to the sides of the label for cleanliness and aesthetics; the face of the label applied to the cassette further comprises an additional color pattern to form a polarizer between the two faces, this at the address of the operator. In addition, this pattern can be recognized by the optical drive and prohibit playback when detected. The pattern is arbitrary, but a simple geometry is convenient to detect in optical reading, as a large circle tangent to both sides of length or a strip parallel to one of the sides. Figure (2) of the plate 1/4 shows a section of different planes parallel to the long direction of the label, to bring the holes in the sectional view; the thickness represented, at scale 1, is 2 millimeters; the thickness range of a label that one wants rigid ranging from half a millimeter to two millimeters. A medical or industrial user can cover his needs in the different exposure configurations: energy, film type, etc., by a reduced number of format and thickness of labels, or even by a single model of label by his dimensions and by its thickness.

  In the invention, the second preferred embodiment of the label in the phase marked b) is that of the flexible label; this label is intended to be affixed in particular on flexible cassettes and also on the objects themselves. The label may be reusable, but it may also be consumable especially when used in combination with a cassette itself consumable. The format of the flexible label: length, width, is included in the same ranges of dimensions as those provided for the rigid label. The variations in thickness relating to the coding correspond to the thicknesses of pellets or discs of a radiation absorbing material, reported on a flexible label support and itself not very absorbent with respect to the radiation. Metal pellets are well suited for this purpose, the constituent materials of these circular pellets are of different types possible: lead, copper, steel, aluminum or their alloys. The pellets are also obtained by mixing a powder of one of the abovementioned metals with an ink or a resin. But for medium or low voltage x-ray X-ray checks, that is to say less than 150 kilovolts, the design of the pellets may allow the use of non-metallic pellets based on hard plastic, cardboard. There is therefore a wide variety of pellets capable of producing sufficient absorption of the radiation, which induces the desired contrast. The thickness of the metal pellets is between 0.1 tenths of a millimeter and 0.5 millimeters for lead pellets, the thickness being chosen at design for an exposure configuration; energy, ... Copper pellets must be thicker than lead pellets for a similar result on the radiographic image, under the same conditions of exposure; and so on when the material of the pellets is less absorbent in a scale relative to the lead. But, for a given exposure configuration, a substantially constant result as to the contrast on the radiographic image, between the bottom of the label and the pellet is obtained by different pellets whose thickness is all the stronger as the material of these is less absorbent. As the maximum thickness of the pellet is not really constrained by radiographic exposure implementation requirements, except that its excessive growth would distance the film from the emergence face of the object. The diameter of the pellets or circular disks is between 1 and 3 millimeters, the smallest diameter corresponding to the smallest label size, while the thickness is correlated to that of the diameter, as for the penetrometer with holes; so for a diameter of 1 millimeter, the thickness is preferably less than 1 millimeter, while for a pellet diameter 3 millimeters, the thickness may be between 1 and 2 millimeters. In the invention, the consumable flexible label, in an economical embodiment is obtained from standard self-adhesive labels of submillimeter thickness, made of paper or plastic, such as polyester or polyvinyl. The manufacture of the label of the invention then consists of sticking circular pellets of hard plastic, copper or lead according to the energy of the radiation. A localized deposit of a resin filled with metal powder is also a means of constituting an absorbent tablet. However, to mix in the waste of labels consumed, on the one hand paper and on the other hand metals, whose lead is not advisable. Therefore, preference is given in the invention to materials for consumable labels pellets, capable of entering the paper or plastic waste treatment cycle, particularly by incineration. In order not to reduce the scope of the applicability of flexible consumable labels, the thickness of the pellets can be increased. When the label must be affixed to an industrial object sensitive to a possible chemical contamination by the glue, then the latter is chosen for this, this in general a limit concentration of chlorine and halogens. Still in the invention, the reusable flexible label, in an economical embodiment is obtained from a small sheet of: flexible plastic such as polyvinyl, polyester, polyethylene-textile - or even leather, this in the format, length and width of the previously indicated label. The thickness of this label support is between a few tenths of a millimeter, up to a millimeter. The absorbent pellets are made of copper or lead in the form of a rivet whose head is flat or round, while the rivet rod is preferably hollow. Once the pellet is placed in its defined position, the rivet pin is struck or crushed, to flare on the face opposite to that where the head is applied. The pellet is thus firmly bonded to the support of the label. Another mode of attachment of the pellets on the support, among many possible modes, is to place them in their defined coordinates, on a self-adhesive adhesive and to cover them with a transparent film, the pellets thus being taken in sandwich between the adhesive backing and the transparent film.

  The label, whether flexible or rigid, consumable or reusable, must be applied intimate manner on the cassette or on the object; for this purpose the label-cassette or object connection function is easily obtained by the application of a layer of adhesive glue on one of the faces of the label. This label maintenance mode is well suited for consumable labels, it is less relevant for reusable labels, although some glues allow repeated repositioning. A simple way to keep the label reusable is to use a clear adhesive tape, overlapping the label. But other possibilities of carrying out this maintenance function are possible. The 2/4 board gives two schematic views of a flexible label, reusable in an embodiment characterized by the gluing on a bottom of the label pellets absorbing radiation. Figure (3) is the plan view of the label, the bottom of the label (11) is made of an adhesive plastic label on one side, on which the absorbent pads (12) and (13) are applied. distributed over the marking area according to known coordinates; the referential of the coordinates of the centers of the pellets is established on the control points (13). A layer of a transparent plastic film (14) is applied over the pellets which are then enchassées. Figure 4 of the end-view label is an exploded view on an enlarged scale in the thickness direction to show the details of embodiment. The consumable cassette is marked by the user but may be marked by the cassette supplier, who preferably applies a consumable label thereto. Still in the invention, the consumable cassette is designed to directly receive the identifier coding during its manufacture or during its loading, so before the supply of the user. In one embodiment of the consumable cassette, the pellets are attached to an outer face of the cassette, which acts as a support for the label, the pellets having the same properties as those intended for the marking labels of the cassettes. Objects. The pellets are preferably of a plastic nature to take into account the waste cycle, however other pellets are possible, as long as they are compatible with the waste cycle of the cassettes. It is recalled that an absolute numbering of the cassettes is not necessary insofar as the counter-marking of the film intervenes quickly after the consumption of the cassette, and it is therefore necessary to ensure the use, thanks to the system of information, that a second cassette bearing a number already used is read, without the counter-marking of the film of the first cassette has intervened; moreover, intrinsically, this situation being highly improbable. In the invention, when radiographic or radioscopic examinations of the same object are to be repeated or repetitive, then the labels are made of durable material adapted to the environmental conditions and thus they can remain permanently installed in the object. itself, on its outer surface, or on its packaging.

  The label of the invention designed in phase a) of the method, and manufactured in the following phase b), is supplied to the user: the medical or industrial radiography service, which therefore obtains batches of labels consumables or reusable.

  The implementation, by the user, of the method of the invention is carried out by the unfolding of the phases marked c) to f), these imply on the one hand a physical process and on the other hand a process of information system. The physical process and the information system process run in parallel, and the tasks of these two sequential processes have logical links. The operation of these processes is shown schematically in boards 3/4 and 4/4. Figure 5 of the plate 3/4 relates to the implementation of the method of the invention with an access of the operators to the radiology information system during the entire cycle of the process, such as radiology cabinet or control service in a production plant. Figure 6 of Plate 4/4 relates to the implementation of the method with access to the information system only for certain phases of the cycle c) to f), as is the case in particular of the ambulatory radiography or on-site radiography of industrial facilities under construction or maintenance. There are similarities, but also differences in the implementation of the method of the invention in these two cases. In the diagrams of Figures 5 and 6, the physical process is shown on the left side of the board, while the information system process is shown on the right side of the board. For the record, and also for the clarity of the explanation to be followed, all the phases of the radiography process are recalled in the physical process, although some of them do not relate to the method of the invention, as for example : reception, radiographic exposure itself, film development. But all the phases of the process of the invention noted from c) to f) are reset in the overall physical process. The following description is that of the implementation of the method of the invention with access to the information system throughout the cycle, such as in a medical office or factory control service and it refers to FIG. 5. The task ( 101) consists in receiving and taking charge of the subject or the object to be radiographed; it is followed by the task (102) in which the operator records on the radiology information system, the data, in particular: subject or object, prescription or specification, prescriber or applicant, radiology entity. These data are entered into a database of the radiology information system. Moreover, some data concerning the subject or the object can be available in the information system of the establishment whether medical or industrial, in this case they can be imported into the radiology information system, this by computer manipulation, the eventual case by optical reading of a barcode on the record of the subject or the object.

  In the task (103), the operator, for a given subject or object to be examined, chooses a preset radiographic procedure, or a shooting scenario; the eventual case it creates a particular procedure, and then it generates the computer list of exposures to be made for the subject or for the object, in which it carries the marking data of each exposure or radiographic view.

  The label bearing its identifier being defined and manufactured as mentioned above, is placed in the scene at the time of the radiographic or radioscopic exposure so that it is projected onto the image receptor without interfering with the regions of interest images. By design and by construction, this label is thin, since it can be placed on the cassette or on the object of the output side of the radiation. The placement of the label near the image receptor maximizes the contrast and sharpness of the thickness variations of the label, and it is this proximity that provides the expected effect with a modest thickness variation. The task (104) consists in marking the cassette by affixing an encoded label, bearing any management identifier, apposition on the input face of the radiation. As an object to be examined, the marking can be done on the emergence face of the radiation rather than on the cassette. But the systematic marking of the cassette is totally operative. The task (104) is identified with the phase (c) of the method of the invention. Phase (d) of the method of the invention relates to the recording of the marking of the cassette, or the object, by reading the label, decoding and registration of its identifier. This registration of the identifier of each X-ray exposure must be done with an indexation of the data of the identification of the subject or the object, and with those of the exposure considered. This phase (d) has three tasks noted (105), (106) and (107). The task (105) is for the operator to call the forecast list of exposures or X-ray views and display it on the screen of a computer console or microcomputer screen equipping the workstation, and then select the exhibition he is about to execute. The task (106) consists, using an optical scanner with surface sensor to read the label placed, corresponding to the selected exposure. The optical reader communicates with the information system of the radiology entity by a wired link or a wireless link: infrared, radio, so that the operator can remotely read the labels placed on an object to examine, arranged in booth or showroom. In this way, the operator can also pick up the marking of all the labels previously placed on different cassettes, provided to post on them a sequence number defined in the radiographic procedure or shooting scenario. The task (107) is that of decoding the identifier of the tag and its record in the database next to the selected exposure. The task (108) is that of the radiographic exposure proper, it is done under the usual conditions; it is followed by the task (109) which is that of the development of the film which is done in manual mode, or generally in an automatic machine. By the method of the invention, the radiographic and radioscopic images of the labels, are in the form of circles or ellipses with low elongation, or dark corresponding to the perforations of the label on a lighter label background, or clear circles relating to the absorbing product thicknesses, the label being then darker. The operator performs an aspect and quality control of the films developed: absence of scratches and development traces, optical density value, framing of the exposure, presence and readability of the radiological image of the label.

  Phase (e) of the method of the invention is that of reading the radiographic image of the label and the return of the data relating to the subject or object concerned by the film; This phase is here decomposed into two tasks noted (110) and (111). The task (110) consists in reading the radiographic image of the label, for this the operator then presents each film in front of the negatoscope and with the aid of the preceding optical reader, he quickly reads and decodes the image of the label; the value or attribute of the identifier is then displayed on a control screen, this screen can be embedded on the reader. The task (111) is to determine the data relating to the subject or object, to its exposure, present in the database, which has been associated with the identifier of the tag during the tasks (102) to ( 107). The optical reader being in communication with the information system, will, after reading, query the database and find, thanks to the indexing previously created, all the data of the identification of the subject or the object, of the exhibition concerned and the marking mark intended for that film. The identification data of the subject or object is then displayed on a terminal or a microcomputer screen and is available to the radiologist.

  This task (111) then consists, automatically after reading and decoding of the radiographic image of the label, to start printing a paper label on which all previously entered data are carried in clear.

  The final phase (f) of the process of the invention is that of the counter-marking of the film by a paper label; in fact the film thus marked being not identifiable without the optical reader, nor the access to the information system. It then consists of counter-marking each film by a self-adhesive paper label bearing in clear all the data returned to each of the films. This phase has two tasks noted (112) and (113). The task (112) is that of the edition of a paper or plastic label by means of a conventional label printer, this edition being triggered automatically after reading the label and restitution on it of the associated data. All the required identification data of the subject or object and those of film marking are then recalled in the information system, to be printed on the paper label. The task (113) is to apply the edited label on the film concerned, so that each film carries in final, all the marks expected or specified. Still in the invention, the description which follows, is that of the implementation of the method of the invention with access to the information system only during certain phases of the cycle, such as in ambulatory radiography or especially in on-site radiography. industrial installations. This description refers to Figure 6 of Plate 4/4. There are technical solutions for accessing a site remote from an institution to its radiology information system, by means such as: internet, autonomous wireless readers, but taking into account industrial environments and operator practices radiographs, preference is given to the present solution which uses a two-layer label. In the process related to the tasks noted in the series (200), the lack of access to the information system is offset by the paper-based use of a projected list of exposures on which, subsequently, the operator carries out a marking report by pasting the duplicate parts of the labels. The list thus completed is read back in the establishment and entered into the radiology information system. The tasks performed on site therefore, without access to the information system, are those contained between the two horizontal dashed lines of FIG. 6, these are the tasks: (205) cassette marking or object and marking report û (206) ) exposure and (207) film development, the latter task relating to the development of the film, however, can be performed at the return of the site.

  The description is made by comparison and also by difference with the tasks given in FIG. 5. The tasks (201) to (204) included are work preparation tasks carried out in the establishment, thus with access to its system. information. The task (201) is the task of reception, identical to the task (101), the task (202) is that of registration, the task (203) concerns the choice of the operating mode and the creation of the provisional list of the exhibitions; the tasks (202) and (203) are identical to the tasks (102) and (103), respectively. The task (204) consists in editing, in paper form, the provisional list of exposures or radiographic views of the object in question, which the operator will bring to go to the intervention site. This operator will also be provided with a batch of two-layer labels, as described in the invention. The task (205) is the task of marking, on the one hand, the cassette or the object by the layer that absorbs the radiation, and on the other hand the transfer of marking on the paper list by sticking the other paper layer thereon. of the label, this to the right of the field or line corresponding to the view that is preparing. The task (206) is that of the exposure, the task (207) is that of the development of the film. Returning from the site, the task (208) is to display the scheduled list of exposures; it is identical to the task (105); the task (209) is to read in turn, on the completed paper list duplicate labels, with the optical reader, the management identifier for each exposure, this task is similar to the task (106). The task (210) consists in recording in the computer database the management identifier assigned to each exposure. The tasks (211), (212, (213), (214) are identical to the tasks (110), (111), (112), (113) and relate respectively to: reading the radiographic image of the - search the database of data for this identifier and launch the edition of self-adhesive paper label - print the paper label - apply the label printed on the label In the following of the method of the invention, during the interpretation of the films, the radiologist reads and decodes the radiographic image and via the information system it imports the workstation and displays on screen, not only the identification data of the subject or the object, its exposure, but other data relating to the history, the acceptance or grading criteria, generally any data useful for interpretation.

  The digital recovery of the film identifier and thus related data recorded in the information system, opens the way to a computerized assistance for the development of the test report, especially through voice recognition. The review report is published, most often in paper form but it is also often available in digital form, so always in the invention the counter-marking of the film can be done after constitution of the account. rendered, in order to be able to print the latter and attach it to the concerned film, which also realizes the identification of the film and does not require counter-marking by label. Another modality consists in coding the examination report, this time using a high density standard matrix coding such as Matrixcode, PDF 417, and to print, on the counter-marking label, this report and code. In addition, a management number for filing and archiving can be assigned to each film and can be printed, in clear and in bar code or matrix code, on the counter-marking label or on the report. exam attached to the film.

  The known means necessary for the implementation of the invention consist in particular of an information system of the radiology entity, comprising software, database, and conventional hardware: network, terminals, PC and their usual peripherals. This information system can be autonomous or communicate with a general information system at the health facility or the industrial establishment. The radiographic or radioscopic images of the object or subject can be digitized by known means, in particular for the films. The observation shows that the practice of film scanning is not widespread, which is why the invention proposes the combined use of a known means namely the viewing negatoscope of radiographic films and a device of the invention. , ie, an optical reader, to scan a limited area of the film but sufficient to read the image of the label. This optical reader functions as a bar code reader or matrix code, but it operates at a low level of light in order to read the radiographic images of the labels and additionally comprises a specific computer program for decoding the labels of the invention; moreover, this decoding program labels can be implanted on a microcomputer that then receives from the reader the raw reading data. The optical reader is a low-level surface sensor type CCD or CMOS, and it reads all the image of the label as a whole. Furthermore, this optical reader is also capable of reading and decoding the barcode labels, or matrix code widely used especially in organizations or companies to locate the objects or their documentation, this faculty allows to call, via the system. information about the subject or subject that may have been recorded in the institution's general information system. This optical reader can capture an area of 10 centimeters squared with a resolution of the order of 100 microns, which is sufficient to detect and decode the label images. The CMOS sensor is particularly suitable here because of its technical characteristics: low slack, anti-glare, logarithmic output, high dynamic range, scan depth from 8 to 12 bits. The cost of CMOS sensors is also lower than that of CCD cameras. Specific software for capturing and decoding labels is implanted on the optical drive; but this software can be deported to a microcomputer which, then, processes the raw images received from the reader. The correct functioning of the optical system for reading the labels and their radiographic images must be periodically checked to ensure the quality of the detection and decoding, which is why in the invention, one or more test tags are produced. and provided to the user as well as the radiographic film (s) corresponding to this or these test labels. The test tag is a rigid metal tag, each cell or cell of the marking zone is pierced with a hole, preferably circular section. The coordinates of the centers of all these holes, in the repository based on the control points, are known and recorded in the radiology information system. This label is thus a kind of test pattern, which, during periodic verifications, provides a metric standard; in the same way for the X-ray film of the test label. The calibration processing software characterizes the repeatability and the fidelity of the reading on the one hand of the label and on the other hand of the film, thus the concordance between the readings of the label and the film. The images of the test label and its radiographic image are scaled using control points whose mutual distances are known and stored. The gaps between the coordinates of the centers of the holes on the one hand of the test label, on the other hand images of the label and its radiography are restored by the calibration software and if necessary, the user is thus alert of exceeding set values of deviations. In one embodiment, the test tag is made of a metal plate: copper or steel, a thickness of 1 millimeter, a size 20 * 50 millimeters, pierced with 100 holes of a diameter of 1 millimeter. In addition, the user can arrange the test tag in the scene during radiographic exposure to evaluate the quality of film detection and decoding under given radiographic exposure operating conditions. Printer self-adhesive paper labels for counter-marking of films can be a standard product of commerce; the launch of the printing being triggered by reading the image of the identifier of the label, the affixing of the label is then made by hand. This counter-marking by hand may present risks of error, which is why one of the means of the invention is characterized by a special label printer. This printer is characterized on the one hand by an additional function to the label printers, consisting of an additional optical reading system of a film area comprising the image of the label, on the other hand by a fitting function automatic printed label. In this way, the edge of the film is introduced into a slot of the special printer, where the identifier of the label is read and decoded, then the counter-marking label is printed and affixed automatically to the edge. of the film, so without any risk of error in the counter-marking.

  When the user has a film scanner, then the optical sensor is not needed to read the x-ray images of the labels, however the coded label marking method remains applicable. The microcomputer at the interpretation station can be connected to a voice recognition dictation system, so that after reading the identifier of the label of a film, the interpreter can dictate his findings and the transmit via the computer network. In the invention, a device for holding the label is provided on the existing cassettes, it consists in reporting on the cassette side incident side of the radiation, a small collapsible case for a standard label format in a given user. The advantages of the method of the invention reside in: • an improvement of the reliability of the identification thanks to the quasi-automation in the composition of the marking and in its reading, thus reducing the human errors • an improvement of the productivity by the reducing the time required for identification and reading • a higher marking contrast than that obtained by light marking, which is poorly accepted in industry • a reduction in the marginal cost (material and labor) of identification, also by the use of reusable labels; • a reduction in size of the area of the image necessary for marking or identification, vis-à-vis the markings by lead letters; control in the location of the marking ensuring the absence of interference between the marking and the regions of interest of the film • a presence, on the front of the cassette, of a mark readable using of the reader, on the contrary light markings • a possibility of assistance by automation thanks to an automatic recovery of the identification data contained in the image, for the interpretation and for the preparation of the examination report A counter-marking of the film by a paper or plastic label, thus readable without a negatoscope, which mentions all the marks expected or specified, and which, moreover, may also comprise in standard matrix form a number of order for management and grading, on the other hand the record of interpretation of the film, at least its conclusion. • a better guarantee of the marking of the area to be x-rayed in the case of complex industrial complexes by affixing the identification label to it, prior to radiographic exposure, either by the person in charge or by the donor of the order when the control is outsourced • a possibility to keep the marking label in place when the object has to be examined at different times • a periodic monitoring of the quality of the optical reading by the test label and the software of The invention finds application in conventional medical radiology film, including general radiology and mammography and in fluoroscopy. But the applications of the invention also relate to all industrial sectors that practice radiography or fluoroscopy in the manufacturing process, installation, maintenance, inspection or expertise. These sectors include: nuclear power, energy, aeronautics, transport, armaments. The processes thus controlled are numerous, in particular we can mention: - welding in equipment or installations - foundry - brazing, bonding - the electronic industry detection of corrosion or cracking of installation or equipment in service - the control of ammunition and pyrotechnic charges - etc. The invention shows its interest by automation, for all companies that have a sustained activity in radiography or radioscopy, but it also finds its interest for other companies whose level activity is less, because it brings a productivity gain with a fast and guaranteed return on investment. Finally, the invention also finds its use in security checks: baggage, parcels, containers, which can thus be identified.

Claims (8)

  An automated method for identifying the radiographic film of an object under examination, using in a known manner the following means: a label for marking the object and its radiographic image coded by an identifier, like the labels in code matrix, * an optical system for reading and decoding on the one hand the label, on the other hand its radiographic image, system communicating with the information system * an information system of the radiology entity considered, for managing and matching by tables and databases, the data of the identifier of each radiographic image with the data previously entered, relating to the identification of the object and the exposure considered * a label self-adhesive to counter-mark in clear radiographic film, data relating to the identification of the object and its radiographic exposure, label edited by a printer of a label characterized by the following consecutive steps: a) - design of a label receiving the data of a management identifier, arbitrary but unique for each label, in a matrix coded form, by visible local variations in thickness and readable on the label, determined to produce corresponding variations in the absorption of radiation causing contrasts, visible and legible on the radiographic images of the label and distributed in an organized manner on the area of the label b) - manufacturing a label, assigned a management identifier, digitized and coded by local variations of thickness defined and organized on the area of the label according to phase a), variations made in under-thickness or extra thickness, a color contrasting with the label background to allow an optical reading of the label c) - marking by affixing the coded label, or on the cass film or on the image receiver on the side of the radiation input face, or on the face of the object of the radiation output side, this to maximize the contrast and sharpness relative to the variations of thickness of label d) - record of the marking of the cassette or the object, for each radiographic exposure, by an optical system ensuring the reading and the decoding of the label and addressing the data of the identifier of the label , to an information system database of the radiology entity, with indexation between these data and previously loaded data, relating to the identification of the object and those of the radiographic exposure e) read from the radiographic image of the label on the exposed and developed film, in combination with a negatoscope, and then decoding of the identifier of the label, thanks to the optical system communicating with the information system, from which restitution of the a correspondence between the identifier of the tag and the identification data of the object, with clear display of this data at the radiologist's interpretation station, and digital replay for assistance with interpretation and establishment of the test report f) -binding-marking of the film by a new printed label, edited by a label printer controlled by the information system, label, preferably self-adhesive, with all data clearly displayed returned from the object identification, radiographic exposure, marking marks, any data previously associated with the coded label   2 - method according to claim 1, characterized in that, in the design step a), for a radiographic control defined by: the object to be examined, the energy of the radiation, the configuration of examination and reading of radiographic images and characterized by an expected value of image quality index, from a given contrast and necessary for optical reading on the radiographic image of thickness variations of the label, the properties are determined, of these local variations of thickness preferably made in a material of high atomic number as to: • their type either in under-thickness or in overthickness • to their geometry, preferably in circular form, or in regular polygonal shape d equivalent area, in order to facilitate their automatic detection, • to their dimensions: section and height respectively in the plane of the label and in a perpendicular direction leading to height thickness variations between 0.1 and 2 millimeters and diameters between 0.5 and 3 millimeters.   3 - method according to claims 1 and 2, characterized in that in the design step a), for each label is defined a unique identifier, arbitrary and coded by a matrix arrangement and particular to each label, a number of local variations of thickness (2) or (121 non-intersecting between them, constituting a specific and distinctive set of positions for the cassette or for the object carrying the label, as for its radiographic image, the numerical value or attribute of the identifier being determined by the combination of the ranks or coordinates of the cells used on the matrix, such as a check grid, the number of variations in thickness being preferably between three and eight, a thickness variation additional to those of the identifier being dedicated to a coding control key.   4 - method according to claims 1 to 3, characterized in that in the manufacturing step b), local variations in the thickness of the label are obtained by perforations (2), a rigid plate of metal or metal alloy: copper, steel, zinc, aluminum, or soft lead tape, but also in some defined configurations of low-energy X-ray examination from tape: cardboard or plastic   5 - process according to claims 1 to 3, characterized in that in the manufacturing step b), local variations in thickness of the label are obtained by deposits (12), pellets of metal: lead, copper, steel, metal powder mixed with an ink or a resin, cardboard or plastic, attached and arranged on a flexible support, weakly absorbing with respect to ionizing radiation, support preferably in small ribbon of paper, plastic, textile, or leather, the pellets being held on their support by gluing or riveting.   6 - method according to claims 1 to 5, characterized in that, in addition to the perforations or pellets constituting the identifier of the label: • in the design step a) of the label, is defined periphery of the label a calibration reference and orientation by control points, preferably the number between three to six, arranged asymmetrically and at known mutual distances, • in the manufacturing step b), is carried out these control points either by additional perforations (3) or by additional deposits (13).   7 - method according to claim 4, characterized in that: - in the manufacturing step b), the wafer or ribbon is composed of 2 superimposed layers and self-adhesive, constituting a labelimmer whose perforated coding is replicated to the same on each layer, the mother-tag comprising, on the one hand, a layer of ionizing radiation-absorbing material intended for marking the cassette or the object and, on the other hand, another low-absorbency paper layer; or colored plastic film, intended for the postponement of marking of the cassette or the object - in the marking step c), after their separation from the mother-label, the absorbent layer is affixed to the cassette or to the object for marking it and its radiographic image, while the weakly absorbent layer is affixed to the tracking document of the object to be examined on which it replicates identically the marking of the cassette or the object, ( 205) the document of su ivi being read later, delayed (209). 8 ù system for carrying out the method, according to one of the preceding claims, characterized in that: - the optical reader provided with a surface sensor type CCD or CMOS, low light level and carrying a specific software for decoding labels, is able to read and decode: • the labels, in step d) • the radiographic images of labels in step e), this in combination with a x-ray viewer • in general, the content standard bar-code or dot-matrix identification labels, marking the object to be examined or its documentation, - the radiology information system, processing the data, in a parallel process and related to the physical process relating to the successive steps: c) cassette marking, d) label reading, e) radiographic image tag reading, f) counter-marking film, for a case of operation, according to the following sequence: • data recording: object, examination, (102) • creation of the operating mode and generation of the forecast list of exposures (103) • selection of the exposure to be made in the provisional list of exposures (105) • decoding of the label and corresponding recording in database (107) • decoding the radiographic image of the label, indexing this code with the data relating to the considered exposure, and launch printing label counter-marking paper (111) 9 - marking label a radiographic or radioscopic image obtained by the method of claims 1 to 7. 10 - consumable cassette of radiographic film characterized in that it incorporates a pre-marking of a management identifier, matrix coded and disposed directly on the outside face by forming additional thicknesses of a radiation-absorbing material, such as added pellets, according to the process of claims 1, 2, 3, 5 and 6.