FR2853979A1 - Patients medical examination information chaining process, involves creating exam zone such that zone has location information, exam result data, and list of external identifiers of specific zones corresponding to specific prior exams - Google Patents

Abstract

The process involves creating the storing objects in a memory (201) such that the object has an identifier of a patient, exam date, and exam zone. The exam zone is created such that the exam zone has an identifier distinguishing the zone from other exam zones, a location information and exam result data. The exam zone has a list of external identifiers of N zones corresponding to N prior exams for the same patient and same zone.

Description

Method for chaining information from medical examinations

  The invention relates to a method for chaining information from medical examinations. The field of the invention is that of medical imaging and of apparatuses making it possible to obtain images or sequences of images of an organ located inside a living being, the living being being of preferably a human being. In particular, the field of the invention is both computed tomography or traditional imaging, as well as magnetic resonance imaging.

  An object of the invention is to record the results of medical analyzes producing images.

  Another object of the invention is to link the results of medical analyzes producing images and relating to the same patient.

  Another object of the invention is to link the results of medical analyzes producing images and relating to the same patient, and to the same analysis area of this patient.

  Another object of the invention is to optimize in time the search for medical analyzes concerning the same area of the same patient.

  Another object of the invention is to describe the development of an anomaly in a medical analysis sequence.

  In the prior art, medical examinations are carried out, the result of which is one or more plane or volume images of one or more areas of a living being. Once acquired, these images are viewed by a practitioner who interprets them. These results are then stored / saved in a memory which can be accessed sequentially.

  One of the problems of the prior art is the measurement of the differences between two examinations carried out on the same patient, for the same area of his body but on different dates. In the state of the art, the practitioner visualizes the images corresponding to the two examinations and visually estimates the differences. This estimate is tainted with a great deal of subjectivity linked to the state of fatigue of the practitioner, the lighting conditions, the perception that the doctor has of the patient's condition, ... to name only the factors the most obvious.

  On the other hand the sequential access mode is handicapping because the number of results to go to find one believes with the number of examinations carried out. So if a practitioner wants to find a previous exam during a new exam, he must spend some time finding this previous exam. This is even more noticeable if it is necessary to find several previous examinations.

  In the invention these problems are solved by linking by reference an examination result to the results of previous examinations. In practice during a radiological examination, images of one or more areas of the body of a living being are produced. An area of the body of a living being is, for example, part of a lung, a kidney, the liver, the heart, a cross section of the rib cage or abdomen ... the list doesn’t is not exhaustive. The result of such an examination is a series of images, flat or solid, each image corresponding to an area of the body. To avoid having to search for previous examinations on the same patient and on the same area of the patient's body, each result / area is linked to the previous results / areas. The link is made using a reference / pointer making it possible to easily distinguish a result / image of an examination from all the results of the examinations previously carried out. This or these references are recorded in a structure also comprising the result of the examination. So when you access this structure you have both the image of the examination result, but also the means to quickly access the previous results.

  By this chaining / link one can also easily propagate markers recorded during the oldest examination of the chain towards the most recent examination. These markers, once the images of the two exams have been readjusted, allow automatic measurement of the development of the marked area. This is an objective measure which greatly facilitates the interpretation of the results of the examination.

  The subject of the invention is therefore a method of chaining information from medical examinations, this information being recorded in a memory, method characterized in that: - the memory is structured into at least one storage object, - an object storage device includes an identifier distinguishing it from a collection of storage objects, - a storage object comprises an identifier of a patient, - a storage object comprises an examination date, - a storage object comprises at least one examination zone, - an examination zone is structured in such a way that an examination zone of a storage object comprises an identifier distinguishing it among the examination zones that the storage object comprises, an examination zone includes location information, - an examination zone comprises an examination result data zone, - an examination zone comprises a list LZ of external identifiers of 10 N zones corresponding to N examinations previous made for the m patient myself and for the same patient's body area.

  Advantageously, the method according to the invention is also characterized in that an identifier from the LZ list is obtained by concatenation of a storage object identifier and an examination area identifier.

  Advantageously, the method according to the invention is also characterized in that N is worth 0 if no previous examination has been carried out for this patient and this location.

  Advantageously, the method according to the invention is also characterized in that the parameters of a new examination are obtained from the parameters of a previous examination, the new examination then being linked to the preceding examination via at least one LZ list. an examination area of the storage object corresponding to the new examination, this list LZ comprising at least one reference to an examination zone of the storage object corresponding to the previous examination.

  Advantageously, the method according to the invention is also characterized in that the list LZ of an examination zone ZE of a storage object OS comprises as many external identifiers as there have been medical examinations prior to the date of examination of the OS object, for the patient identified by the OS object, and for the location of the ZE zone.

  Advantageously, the method according to the invention is also characterized in that an examination area includes a field for recording at least one marker making it possible to define an area of interest in the content of the data area resulting from examination.

  Advantageously, the method according to the invention is also characterized in that when the content of a result data area is observed, the content of the LZ list is used to retrieve markers from at least one related examination, the retrieved markers being viewed at the same time as the content of the data area.

  The invention will be better understood on reading the description which follows 5 and on examining the accompanying figures. These are presented by way of non-limiting indication of the invention. The figures show: - Figure 1: an illustration of steps of a process implementing the process according to the invention.

  - Figure 2: an illustration of a memory structured according to the method 10 according to the invention.

  - Figure 3: An illustration of a device implementing the method according to the invention.

  - Figure 4: An illustration of images from examination of the same area of the same patient on different dates.

  In the description, the described actions are carried out automatically, that is to say without human intervention once the process is launched. That is to say, when an action is lent to an apparatus, this action is carried out by a microprocessor of this apparatus, said microprocessor being controlled by instruction codes recorded in a program memory of the apparatus.

  FIG. 1 shows a preliminary step 101 for setting up an examination. In our example we consider that it is a radiological examination of the conventional scanner type, that is to say computed tomography.

  In practice, this may be any medical examination producing one or more images to be interpreted.

  Figure 3 shows a patient 301 lying on a table 302 of an X-ray machine 303. The invention is not limited to this type of device, it can also very well be devices with which the patient is standing or with which the table is tilted. When it is thus positioned, the patient 301 30 can be exposed to radiation from a tube 304, in our example X-ray. This radiation is received, after passing through the patient 301, by a sensor 305.

  The radiological apparatus 303 is also connected to a control terminal 306 which makes it possible both to control the apparatus 303 and to receive the information produced by the sensor 305 during the examination. This information makes it possible to produce images which will be interpreted by a practitioner.

  The terminal 306 is also connected to an output device 307, for example a screen 307, and to at least one input device 308, for example a keyboard, a mouse. The peripheral 308 makes it possible to control the radiological apparatus 303, and in particular to define the parameters of an examination. Among these parameters we cite the definition of one or more areas of the patient's body to be imaged, exposure parameters defining the amount of radiation that the patient will receive .... The peripheral 307 10 allows on the one hand to have feedback on the proper consideration of the above parameters, and on the other hand to view the results / images of the examination.

  The terminal 306 also comprises, in addition to means for connection to the apparatus 303 and to the peripherals 307 and 308, a microprocessor 309, a program memory 310 and a storage memory 311. The various means of the terminal 306 are interconnected via a bus 312. The microprocessor 309 is controlled by instruction codes recorded in the memory 310. The memory 310 includes instruction codes corresponding to the implementation of the method of FIG. 1, and to the method 20 according to the invention.

  Step 101 is followed by a step 102 for creating a storage object according to the invention. A storage object can be assimilated, for example, to a file, to a part of a file, to a database, to a part of a database or to several of these elements linked together. 25 For the description, it is considered to be a file with a particular structure. In practice, the structure of such a storage object can be described via an XML syntax (eXtended Markup Language, for extended markup language), via an RTSS object (RadioTherapy Structure Set, for a structured set for radiotherapy) as described by DICOM (Digital 30 Communication in Medicine, for digital communication in medicine), or via a fixed multi-field structure, each field having a fixed length, the list is not exhaustive.

  Figure 2 shows such a structure for a storage object according to the invention. Figure 2 shows a part 201 of the storage memory 311. The part 201 of the memory 311 is also indifferently called memory 201. This illustrates the fact that the representation of the memories in the figures is functional. In practice, memories can be unified on the same component or distributed over several components. It is also possible that the memory 201 is distributed over several components of the hard disk type.

  FIG. 2 shows that the memory 201 comprises 3 storage objects 202 to 204. For example, each object is a file. A storage object according to the invention is structured in several parts. A storage object essentially comprises for the invention 2 parts which are a header and a body. The body itself has several examination areas. The header contains information common to the examination areas of the storage object. Each examination area includes information from a radiological examination of an anatomical location, each examination area therefore corresponds to an anatomical location of the patient's body.

  Thus the structure of the storage object produced in step 102 depends on the configuration of the examination carried out in step 101. Indeed the storage object produced in step 102 will include as many examination zones as the practitioner will have configured anatomical locations of the patient's body to be imaged during the examination.

  FIG. 2 thus shows that the storage object 202 comprises a header 205 and a body 206. The body 206 comprises 2 examination areas 207 and 208, but the body 206 could contain more examination area as previously explained.

  The header 205 includes an idO field making it possible to identify the storage object 202 among the collection of storage objects that the memory 201 contains. For the object 202, idO is 1. The format of the idO field can be any, numeric or alphanumeric. In terms of the database, idO is a primary key for the storage object.

  The header 205 includes an idP field making it possible to identify the patient 30 who is undergoing the examination which gave rise to the creation of the storage object 202.

  For object 202, idP is 1. The format of idP is also arbitrary, numeric or alphanumeric. It is also a primary key, but for one patient, among all patients. A good solution for the idP format is to use a Social Security number type number for example.

  The header 205 includes a Date field making it possible to specify the date on which the examination which gave rise to the creation of the object 202 took place.

  For the object 202 Date is worth 112/2002. All existing date formats can be used. The Date field is used to classify storage objects chronologically. Among the possible formats we cite: ddlmm / yyyy, yy / mm / dd, the 5 number of seconds elapsed since midnight January 1, 1972 ... the list is not exhaustive.

  The examination area 207 includes an idZ field making it possible to identify the examination area 207 from among the examination areas that the storage object 202 contains. For the area 207 idZ is 1. The format of idZ meets the same specifications as the format of idO. A good format for idZ is to successively number the examination areas of a storage object.

  The examination zone 207 includes a loc localization field making it possible to define an anatomical localization in the patient's body which gave rise to the creation of the examination zone 207. Such localization 15 is expressed either in Cartesian coordinates, or in a coordinate system specific to radiology such as the LPS (Left Posterior Superior) system. This localization field comes directly from the configuration of the examination in step 101, it defines the area of the patient's body imaged.

  The examination area 207 includes a field Mar allowing definition of markers. Each marker is expressed in a coordinate system as previously mentioned. At least one marker makes it possible to associate an area of interest with the image or series of images of the examination area 207. In other words, a marker makes it possible to define an area of interest in an image or series of images, resulting from the examination. The markers are therefore defined after the examination. The Mar area has any number of markers, possibly none.

  More precisely, a marker comprises a series of coordinates making it possible to define a point in the image / result to which the marker is attached. A marker also includes an extraction method applied from this point. An extraction method is, for example, a segmentation, a measurement of the longest axis ... the list is not exhaustive.

  The result of the extraction method applied from the point of the marker is a measure used to characterize the area of interest. Depending on the extraction method used, it may be a volume (segmentation), a distance (method of the largest axis) or any size allowing a comparison to be made between several quantities of this nature. .

  The area 207 comprises data data which are the result of the examination for the area of the image of the patient's body which gave rise to the creation of the examination area 207. The Data field therefore comprises a plane or volume image according to the type of exam performed. If a continuous type examination is carried out, the data zone in fact comprises a sequence of images. In practice, the Data field contains not the image itself, but a reference to the image. In other words, the Data field 10 includes an address allowing access to a structure, for example a file, comprising the image data proper. Such an address is for example a file name, a key in a database or the like.

  Zone 207 includes a field Lz comprising a list of 15 references to other examination zones.

  The description made for the storage object 202 and the examination zone 207 is valid for all the storage objects and the examination zones according to the invention, except of course for the values of the fields which vary from one object to another and from one exam area to another.

  Once the storage object has been created, it is filled with information / data from the radiological examination.

  In step 103, following step 102, the terminal 306 transmits to the radiological device 303 the parameters corresponding to the first area of the patient's body to be imaged. In step 103, the active examination zone is the first examination zone of the storage object created in step 102. Then we pass to an acquisition step 104 during which the device 103 acquires information according to the exposure and location parameters transmitted to it. Step 104 is followed by a step 105 for recording data from step 104. In step 105 the device 303 transmits 30 to the console 306 the data from step 104. The console records the data received in the Data field of the active examination area.

  We then go to a step 106 in which the terminal 306 determines whether there is another area of the patient to be imaged. This determination is made as a function of the configuration carried out in step 101. If there remains an area of the patient to be imaged, we go to a step 107, otherwise we go to a chaining step 108.

  In step 107, the terminal 306 transmits to the radiological apparatus 303 the parameters of the area of the patient's body to be imaged according to that which has just been imaged. The active examination zone becomes the examination zone following that updated following step 105. From step 107 we go to step 104.

  Step 108 makes it possible to make a link between the different examination zones of the different storage objects relating to the same patient.

  In practice, step 108 could also be located after any one of steps 102 to 107.

  Let us consider the case of an examination I having produced the storage object 202. The storage object 202 comprises, as we have already seen, 2 examination zones 207 and 208 identified, in the storage object 202, by the idZ values being 1 and 2 respectively. Each of these examination zones corresponds to an area of the patient's body identified by the value 1 for the idP field. Let us assume that examination I is the first examination of the patient identified by the idP field. In this case the chaining step 108 is unnecessary since there is no previous information for this patient.

  From step 108, we then go to a viewing step 109. In step 109, the practitioner visualizes the images that comprise the Data 20 fields of the examination areas created during examination 1.

  FIG. 4 shows an image 401, for example a sectional view of a lung 405. Let us consider that image 401 corresponds to the Data zone of the examination zone idZ = 2 of the object idO = 1. The figure 4 shows that the lung 405 has a nodule 402. Here a nodule is, for example, something not corresponding to healthy lung cells. The practitioner can then place a marker 403 in the nodule 402. The marker 403 is recorded in the field Mar of the examination zone corresponding to the image viewed by the practitioner. The marker is visualized on the screen, superimposed with the image of the lung 405. This simultaneous visualization of image plus marker facilitates the task of the practitioner by allowing him to clearly visualize the measurement points corresponding to the markers. The practitioner can thus proceed with the insertion of markers for each examination area of the object 202. The number of markers is left to the practitioner's initiative.

  A marker once placed gives access to a quantity of 35 measurements. In the example of FIG. 4, this is the visualization of a lung comprising a nodule marked by the marker 403. In this case, the extraction method by segmentation is generally associated with the marker, which allows to obtain the volume of nodule 402 on the date of acquisition of image 401.

  Step 109 can be followed or preceded by a step 110 for comparing successive examination results. In the case of examination 1, this step 110 does not need to be since it is a first examination.

  Steps 101 to 110 are implemented for each examination.

  FIG. 2 shows that the storage object 203 has a structure 10 identical, a header and a body, to the structure of the object 202. Let us consider that the storage object 203 corresponds to an examination II carried out after the exam I but for the same patient, and for only one area of the patient's body. This area of the patient's body corresponds to the examination area identified by the identifier idZ = 2 in the storage object 15 identified by the identifier idO = 1.

  The examination It results in the production of the storage object 203 in which idO is worth 40, idP is worth 1 and Date is worth 01/0412002, that is to say the date on which the examination was made 11. We note that the value of idP for objects 202 and 203 is identical, which is consistent since these two storage objects correspond to the same patient. The difference between the idO values of the storage objects represented in FIG. 2 is due to the fact that between the dates of creation of these storage objects there have been other examinations concerning other patients. These other storage objects are present, although not shown, in the memory 201 and the values of their idP fields 25 depend on the patients to which they correspond.

  The storage object 203 only has a single examination area 209 because only one area of the patient's body was imaged during the examination II.

  For this examination zone idZ is equal to 1 and Data contains the image of the examination II.

  In step 108, the practitioner completes the field Lz of the examination area 209. In fact patient 1 (idP) has already undergone an examination for this area of his body. Said field Lz then includes a reference to the result of this examination. In this case this reference is worth 1.2. This reference can be interpreted as idO.idZ. This reference is therefore a concatenation of a storage object identifier and an examination area identifier. he

  Thanks to this reference, it is therefore possible, no doubt possible, to find an examination area for a storage object.

  In the description, a notation x.y designates the examination area y of the storage object x, relative to FIG. 2.

  In a variant, each examination zone comprises a unique identifier making it possible to distinguish it among all the examination zones of the memory 201. This unique identifier can then also be used as a reference for establishing links between the examination zones .

  The information of the zone Lz is produced by the practitioner who, during step 10, designates the storage object corresponding to the previous examination to which the examination II which has just been carried out must be linked. Then it then designates for each examination area of the object 203 the examination area of the object 202 to which it must be linked.

  Alternatively, this intelligence process is automated using location information. Indeed, a link is created between two examination areas corresponding to the same area of the body of the same patient. Knowing a patient identifier and location information therefore makes it possible to link examination areas.

  The visualization of the examination result There is an image 406 of the lung 405 in which a nodule 404 is seen. As for image 401, the practitioner can insert a marker 407 making it possible to obtain a volume measurement for the nodule 404 Thanks to the existing link, after step 108, between the examination area 40.1 and the examination area 1.2, the terminal can obtain the content of the field Mar of the examination area 1.2 and display the markers of this area on image 406 corresponding to area 40.1 of examination. FIG. 4 therefore shows a marker 407 placed by the practitioner and the marker 403 obtained by the link existing between the zones 40.1 and 1.2. This is a spread of markers between exams. This propagation is a sub-step 111 of the comparison step 110.

  In practice, the marker 403 is displayed on the image 406 after a registration between the images 401 and 406. In fact the reference of the coordinates between the examination I and the examination It is not the same insofar as o the patient was not necessarily positioned in exactly the same manner relative to the image acquisition device. It is therefore useful to perform a registration between the image 406 and the image 401. This registration makes it possible to determine which transformation to apply to the coordinates expressed relative to the area 1.2 of examination so that these coordinates are usable in the system of coordinates of exam area 40.1. This registration is done, for example, based on any remarkable element of the 5 images to register. A rigid registration is usable but we prefer a non-rigid registration allowing the deformation of the organs to be taken into account. This limitation in the coordinate system and also to be taken into account in the variant of automatic link establishment. It may indeed here also be useful to perform a registration or to use a tolerance on the location information which is not exactly identical for the same anatomical area of the same patient from one examination to another.

  The fact of being able to propagate the markers from an examination zone Z1 to the following examination zone Z2, therefore from a series of images to the following, effectively relieves the practitioner from having to place a marker in a new series of images when there is a previous review. Indeed, the practitioner then only has to make sure that the propagation of the marker, with or without registration, from Zl to Z2 has gone well, possibly slightly replacing the marker in Z2 to put it more in the center of the zone 20 of interest and to save in the examination zone Z2 the Zl marker thus propagated. Verification by the practitioner is done visually by looking at where the propagated marker is displayed in the examination zone Z2.

  The fact that the practitioner can simultaneously view images and markers linked (at the anatomical location level) and resulting from two distant examinations over time provides him with objective information on the evolution of the nodule, in particular on the evolution of its size, between the two exams I and 11. This makes it possible, during the comparison step 110, to determine the evolution of the nodule objectively. Indeed, for example in the case of image 406, it clearly appears that the markers 403 and 407 produce indications of volume such that the nodule 404 is larger than the nodule 402. This clearly means that the nodule 402 has gets bigger between exam I and exam II. Here the marker 407 is in fact the marker 403 which has been propagated from the zone 1.2 towards the zone 40.1, then refocused. The recentering is either automatic by registration, or manual and done by the practitioner. The result of the propagation and of the recentering is recorded in the field Mar of zone 40.1.

  In practice when propagating a marker, the extraction method linked to this marker is retained. This allows, from one examination to another, to obtain comparable quantities.

  FIG. 4 also shows a third storage object 204 whose identifier idO is equal to 150, corresponding to an examination carried out on the patient identified by idP = 1, on the date of 07/01/2002, and relating to three areas of the body of this patient. The storage object 204 therefore comprises three examination areas 210 to 212.

  The 150.1 exam area is linked to the 1.1 exam area. Exam area 150.2 is linked to exam areas 40.1 and 1.2. The examination area 150.3 is not linked to any examination area. The cases of zones 150.1 and 150.3 have already been treated for objects 202 and 203.

  The case of the examination zone 150.2 is specific in that the field 15 Lz of this zone comprises several references. In practice, the field Lz of an examination zone includes a reference to each of the examinations which precedes it for the same zone of the body of the same patient. In the case of the 150.2 examination zone, the Lz field indicates that there have already been two previous examinations for the zone of the body of the corresponding patient. This allows the practitioner viewing the examination 11I1 corresponding to the object 204 to view the propagation of the markers over the duration of all the examinations preceding, in the present case of examinations 1, II and 11I1. This case illustrates that in step 108, when the practitioner designates an examination area of an old storage object to be linked to an examination area of a new storage object, the terminal 306 performs the link / chaining by importing into the Mar field of the examination area of the new storage object the complete content of the Mar field of the examination area of the old storage object.

  Object 204 also illustrates the fact that a storage object, and therefore an examination for a patient, does not necessarily relate to the same zones as the immediately preceding examination of this patient, as illustrated by the zone 150.1 of examination which is not linked to examination II but to examination 1.

  Likewise, a new examination may relate to new areas of the patient's body, as illustrated by the 150.3 examination zone which had never been the subject of any previous examination.

  However, in a variant, it is possible that the setting step 101 is carried out as a function of the content of an anterior storage object designated by the practitioner during step 101. This makes it possible to carry out an examination relating exactly to the same areas of the patient's body. The definition of these zones, in particular the anatomical location, is adapted as a function of the patient's position relative to the image acquisition device 303.

  In practice, the field Lz of an examination zone ZE comprises as many identifiers of examination zones as there have been examination for the zone of the patient's body corresponding to the examination zone ZE. This allows quick access to all of the track records. This also eliminates the risks associated with the deletion of a storage object or an examination area.

  Indeed insofar as each examination zone includes a reference to all the examination zones which precedes it, the loss of an examination zone has no consequence on the links between the remaining examination zones.

  The fact of thus linking the examination zones also allows easy access to the Date fields of the storage objects, and therefore to accurately measure the evolution linked to the markers over time. In practice, markers make it possible to produce a volume, distance or other value. With the date information one can therefore easily assess the growth, positive or negative, of a nodule. Either its volume increases, or it decreases. An evolution curve is thus easily obtained with the time on the abscissa and the volume or any quantity produced by the extraction method associated with the marker on the ordinate. This curve also gives, by derivation, information on the speed of evolution of the nodule.

Claims (6)

  1 - Method for chaining information from medical examinations, this information being recorded in a memory, method characterized in that: - the memory is structured into at least one storage object, - a storage object comprises an identifier distinguishing it among a collection of storage objects, - a storage object comprises an identifier of a patient, 10 - a storage object comprises an examination date, - a storage object comprises at least one examination zone, - an examination area is structured in such a way that - an examination area of a storage object comprises an identifier distinguishing it from among the examination areas that the storage object comprises, - an examination area the examination includes location information - an examination zone comprises an examination result data zone, - an examination zone comprises a list LZ of external identifiers of N zones corresponding to N previous examinations carried out for the same 20 patient and for the same area of the patient's body.   2 - Method according to claim 1, characterized in that an identifier of the LZ list is obtained by concatenation of a storage object identifier and an examination area identifier.   3 - Method according to one of claims 1 or 2, characterized in that N is worth 0 if no previous examination has been carried out for this patient and this location.   4 - Method according to one of claims 1 to 3, characterized in that the parameters of a new examination are obtained from the parameters of a previous examination, the new examination then being linked to the preceding examination via at at least one LZ list of an examination zone of the storage object corresponding to the new examination, this LZ list comprising at least one reference to an examination zone of the storage object corresponding to the previous examination.   - Method according to one of claims 1 to 4, characterized in that the list LZ of an examination zone ZE of an OS storage object comprises as many external identifiers as there have been examinations prior to the date of examination of the OS object, for the patient identified by the OS object, and for the location of the ZE zone.   6 - Method according to one of claims 1 to 5, characterized in that an examination area includes a field for the recording of at least one marker making it possible to define an area of interest in the content of the examination result data area.   7 - Method according to claim 6, characterized in that during an observation of the content of a result data area, the content of the LZ list is used to retrieve markers from at least one related examination, the markers retrieved being viewed at the same time as the contents of the data area.