Patent Description:
An x-ray emitter includes an x-ray source designed to generate and then emit an x-ray beam; at least one collimator defining the shape of the beam; and a filter for removing the low-energy component that is not useful for creating the image and is harmful to the patient.

A collimator is usually divided into two parts, i.e. a fixed primary collimator, placed upstream of the filter, having the shape of a truncated cone and defining the maximum angular dispersion of the beam; and a secondary collimator, placed downstream of the filter, consisting of two pairs of variable opening blocks defining the size of the treatment field.

In some cases, the radiological devices may include a portal defining an analysis zone wherein the portion to be analysed is inserted, supporting, and commanding the emitter and detector to rotate.

Example of radiological imaging device are disclosed in <CIT>, <CIT> and <CIT>.

The described prior art comprises some significant drawbacks.

In particular, the filters on the market today are specific to only one type of radiological acquisition; therefore, multifunctional radiological imaging devices, i.e. those able to perform two or more fluoroscopies, radiographs, or tomographies, require one or more filters for each type of acquisition.

For this reason, they must be equipped with an exchange member that varies the filter hit by the X-ray beam according to the acquisition to be carried out. This solution, in addition to increasing the costs and size of the devices, makes it impossible to have an adequate number of filters.

For the reasons explained above, multifunctional radiological imaging devices are expensive and complex to implement and, therefore, not very widespread today. Under these circumstances, the technical purpose underlying the present invention is to devise a radiological filter that is able to substantially overcome at least some of the drawbacks mentioned above.

Within the sphere of said technical purpose, one important purpose of the invention is to obtain a radiological filter that can be used for more than one type of radiological acquisition.

In particular, an important purpose of the invention is to provide a multifunctional radiological device with reduced costs and a reduced size.

The technical task and the specified purposes are achieved by means of an emitter including a radiological filter as claimed in the appended claim <NUM>. Examples of preferred embodiments are described in the dependent claims. The invention is further defined by the radiological imaging procedure according to claim <NUM>.

The characteristics and advantages of the invention are clarified by the following detailed description of preferred embodiments thereof, with reference to the accompanying drawings, wherein:.

In the present document, the measurements, values, shapes and geometric references (such as perpendicularity and parallelism), when associated with words like "almost" or other similar terms such as "approximately" or "substantially", are to be understood as except for measurement errors or inaccuracies owing to production and/or manufacturing errors and, above all, except for a slight divergence from the value, measurement, shape, or geometric reference with which it is associated. For example, if such terms are associated with a value, they preferably indicate a divergence of not more than <NUM>% of the same value.

Furthermore, when used, terms such as "first", "second", "higher", "lower", "main" and "secondary" do not necessarily identify an order, relationship priority, or relative position, but they can simply be used to distinguish more clearly between different components.

The measurements and data provided in this text are to be considered as performed in ICAO International Standard Atmosphere (ISO <NUM>), unless otherwise indicated. Unless otherwise indicated, as evidenced by the discussions below, it should be understood that terms such as "processing", "computer", "computing", "evaluation", or the like, refer to the action and/or processes of a computer or similar electronic calculation device, which handles and/or processes data represented as physical, such as electronic sizes of logs of a computer system and/or their memories, other data similarly represented as physical quantities inside computer systems, logs or other information storage, transmission or display devices.

With reference to the figures, reference numeral <NUM> globally denotes the radiological filter according to the invention.

The radiological filter <NUM> may be part of an x-ray emitter <NUM> and, in particular, of an x-ray beam 10a.

Preferably, it can be part of a radiological imaging device <NUM> designed to carry out radiological imaging of at least part of a patient 1d. Preferably, the radiological imaging device <NUM> is multifunctional and, to be precise, able to carry out a tomography and at least one of either fluoroscopy or radiography. In detail, the imaging device <NUM> is multifunctional and capable of performing tomography, fluoroscopy, and radiography.

It should be noted that the patient 1d can be either human or animal.

The x-ray beam 10a defines an emission axis 10b that is barycentric to the beam. It can be conical.

The radiological filter <NUM> defines a longitudinal axis 1a; a first working surface <NUM>b and a second working surface 1c opposite the first working surface 1b with respect to the same radiological filter <NUM>.

The working surfaces 1b and 1c define the surfaces for which the x-ray beam 10a passes through the radiological filter and then through which the x-ray beam 10a enters and exits the radiological filter <NUM>. The x-ray beam 10a preferably enters the radiological filter <NUM> through the second working surface 1c and exits the radiological filter <NUM> through the first working surface 1b.

The first working surface 1b is on the opposite side to the second working surface 1c in relation to the same radiological filter <NUM>.

The radiological filter <NUM> comprises a first sector <NUM> defining a first portion 2a of the first working surface 1b, which is substantially flat, and a second sector <NUM> defining a second portion 3a of the first working surface 1b, the profile of which is substantially curved, extending along the longitudinal axis 1a.

The sectors <NUM> and <NUM> extend substantially parallel to the longitudinal axis 1a. As a result, the radiological filter <NUM> has an L-like profile.

In detail, the second portion 3a has the profile of a semi-parabola extending along the longitudinal axis 1a.

The semi-parabola has a symmetry axis parallel to the first portion 2a.

The semi-parabola has an external focus and, more specifically, on the opposite side of the radiological filter <NUM>.

The second portion 3a is complementary to the first portion 2a in relation to the first working surface 1b and, therefore, totally defined by the portions 2a and 3a.

The second working surface 1c is substantially flat and, more specifically, parallel to the first portion 2a.

The first sector <NUM> defines an additional first portion of the second working surface 1c.

The additional first portion can be substantially flat. Alternatively, it may have a substantially curved profile extending along the longitudinal axis 1a.

The second sector <NUM> defines an additional second portion 3a of the second working surface 1c that is substantially flat.

The additional second portion can be substantially flat. Alternatively, it may have a substantially curved profile extending along the longitudinal axis 1a.

The additional second portion is complementary to the additional first portion 2a in relation to the second working surface 1c and, therefore, totally defined by the additional portions.

The first sector <NUM> and the second sector <NUM> can be made of a single piece.

The radiological filter <NUM> is designed to remove one component of the x-ray beam and, in particular, the low-energycomponent. To this end, the sectors <NUM> and <NUM> are made of a material designed to be passed through, conveniently partially, by the x-ray beam. Said material can be a material such as aluminium or copper. Or polymeric materials, such as Teflon.

The emitter <NUM> comprises at least one radiological filter <NUM> and, more specifically, only one radiological filter <NUM>.

The emitter <NUM> comprises at least one source <NUM>, conveniently one source only, designed to emit a beam of x-rays 10a hitting the filter <NUM> on the surface that is hit 1a. The source <NUM> is designed to emit an x-ray beam 10a defining a focal spot 11a.

It should be noted that the radiological filter <NUM> preferably always remains stationary at the focal spot 11a.

The source <NUM> may be of a known type.

The radiological filter is between the source <NUM> and patient 1d.

The x-ray emitter <NUM> can comprise a collimator <NUM> of the x-ray beam 10a.

The collimator <NUM> is designed to define the shape of the beam 10a hitting the radiological filter <NUM> and then the patient 1d.

It is located between the source <NUM> and radiological filter <NUM> so as to intercept the beam before it reaches the radiological filter <NUM>.

Alternatively, the radiological filter <NUM> is located between the source <NUM> and the collimator <NUM> so as to intercept the beam before it reaches the collimator <NUM>.

The radiological filter <NUM> defines several working conditions based on the portion of the first working surface 1b hit by the x-ray beam 10a. More specifically, it defines a first operating condition wherein the x-ray beam 10a hits, preferably exclusively, the first portion 2a; and a second operating condition wherein the beam 10a hits at least the second portion 3a.

In particular, in this condition, the x-ray beam 10a exclusively hits the second portion 3a or, preferably, the second portion 3a and part (more specifically, only a limited part) of the first portion 2a.

In order to change the operating condition, the emitter <NUM> comprises a handler defining relative motion between the radiological filter <NUM> and the x-ray beam 10a and, in particular, between the radiological filter <NUM> and at least one of either the collimator <NUM> or the source <NUM>.

It should be specified that the handler never commands a change of operating condition during scanning. As a result, during the scan, the part of the first working surface 1b that the x-ray beam 10a hits does not change.

The handler can be translational, i.e. designed to change the operating condition of the radiological filter <NUM> by means of a translation along a sliding axis. It can be designed to translate the radiological filter <NUM> in relation to the source <NUM> and, more specifically, to the collimator <NUM> (<FIG>) or the radiological filter <NUM> and the collimator <NUM> in relation to the source <NUM> (<FIG>).

The sliding axis can be substantially transverse to the emission axis 10b.

The sliding axis can be substantially transverse and preferably perpendicular to the longitudinal axis 1a and, suitably, substantially parallel to the second working surface 1b.

Alternatively, the handler can be rotational, i.e. it can be designed to change the operating condition of the radiological filter <NUM> by rotating around said rotation axis. It can be designed to rotate the source <NUM> and, more specifically, the collimator <NUM> in relation to the radiological filter <NUM> (<FIG>).

The rotation axis can be substantially transverse to the emission axis 10b.

The rotation axis can be substantially parallel to the longitudinal axis 1a and, conveniently, to the second working surface 1b.

The rotation axis can pass through the focal spot 11a.

In some cases, the handler can be both rotational and translational.

The emitter <NUM> may, additionally, comprise at least one additional radiological filter; and an exchange system, such as a slide, for the filter that is hit by the x-ray beam that is designed to enable only one of either the radiological filter <NUM> or the additional filter to be hit by the beam 10a.

The additional radiological filter may be of a known type.

The radiological imaging device <NUM> comprises at least one radiological filter <NUM>, in particular at least one emitter <NUM>, conveniently of an x-ray beam 10a.

The radiological imaging device <NUM> comprises only one emitter <NUM>.

The radiological imaging device <NUM> comprises only one radiological filter <NUM> so that the x-ray beam passes through only one radiological filter <NUM>.

The x-ray imaging device <NUM> comprises at least one detector <NUM> designed to be hit by the x-ray beam 10a after it has passed through the filter <NUM> and at least one sector of the patient part 1d.

The detector <NUM> is conveniently designed to selectively carry out tomographies, fluoroscopies, and/or radiographies, according to a command given by the operator.

The detector <NUM> comprises at least one sensor <NUM> defining an x-ray sensitive surface 21a designed to be hit by the x-ray beam 10a.

The sensitive surface 21a is substantially parallel to the longitudinal axis 1a.

The detector <NUM> can comprise a shifting assembly <NUM> designed to handle the sensor <NUM> in relation to the emitter <NUM> by defining two or more acquisition positions and, in particular, between a first acquisition position (<FIG>) and a second acquisition position (<FIG>).

In the acquisition positions, the emission axis 10b can hit the centre of the sensitive surface 21a.

The shifting assembly <NUM> defines a shifting axis 22a and, conveniently, a shifting range, i.e. a distance between the sensor <NUM> in the first acquisition position and the sensor <NUM> in the second acquisition position.

Preferably, said shifting range is less than the extension of the sensitive surface 21a along the shifting axis. As a result, there is an overlap between the sensitive surface 21a in the first acquisition position and the sensitive surface 21a in the second acquisition position.

The shifting axis 22a is substantially parallel to the sensitive surface 2c.

It is substantially perpendicular to the longitudinal axis 1a.

The shifting assembly <NUM> comprises a cursor <NUM> connected to the sensor <NUM>, a shifting guide <NUM> defining the shifting axis 22a and a motor, more specifically an electric motor, to command the motion of the cursor <NUM> on the shifting guide <NUM>. The radiological imaging device <NUM> defines multiple working configurations depending on the operating condition and acquisition position.

Preferably, it defines a first working configuration wherein the radiological filter <NUM> is in the first operating condition and the sensor <NUM> is in the first acquisition position (<FIG>); and a second working configuration wherein the radiological filter <NUM> is in the second operating condition and the sensor <NUM> in the second acquisition position (<FIG>).

The radiological imaging device <NUM> comprises an anchor block <NUM> for the detector <NUM> and the emitter <NUM>.

The anchor block <NUM> defines an analysis zone 30a between the detector <NUM> and the emitter <NUM> and wherein, conveniently, at least one sector of the patient part 1d is arranged to be scanned.

The radiological imaging device <NUM> is designed to carry out a scan by carrying out a plurality of acquisitions from different points. Therefore, the anchor block <NUM> is designed to define a motion relative to the patient 1d and to the assembly consisting of the emitter <NUM> and detector <NUM>, by defining an acquisition axis 30b.

The acquisition axis 30b can be substantially barycentric to the analysis zone 30a. It may be substantially parallel to the sensitive surface 22a.

The acquisition axis 30b can be substantially parallel to the longitudinal axis 1a.

It should be noted that the radiological filter <NUM> preferably always remains stationary at the acquisition axis 11a.

The anchor block <NUM> can be designed to define a reciprocal rotation between the patient 1d and the assembly consisting of the emitter <NUM> and detector <NUM> around the acquisition axis 30b and, to be precise, to rotate the emitter-detector assembly in relation to the patient 1c around the acquisition axis 30b. For this purpose, it comprises a rotor part <NUM> designed to support the emitter <NUM> and source <NUM> and a stator part <NUM> designed to support the rotor part <NUM> allowing it to rotate around said acquisition axis 30b.

The anchor block <NUM> may comprise a gantry or C-arm.

As an alternative or in addition, the anchor block <NUM> can be designed to define a reciprocal translation between the patient 1d and the assembly consisting of the emitter <NUM> and detector <NUM> along the acquisition axis 30b.

The acquisition block <NUM> can, therefore, comprise a track <NUM> defining the acquisition axis 30b; and a carriage <NUM> to which the emitter <NUM> and the detector <NUM> are connected and designed to run along the track <NUM>.

Conveniently, the anchor block <NUM> is designed to define a reciprocal rotation and translation between the emitter assembly <NUM> and detector <NUM> and patient 1d. It therefore comprises said rotor part <NUM>, said stator part <NUM>, said track <NUM> and said carriage <NUM> to which said parts <NUM> and <NUM> are connected as shown in <FIG>.

The radiological imaging device <NUM> comprises at least one patient support 1d. The support is, for example, a radiographic couch.

The radiological imaging device <NUM> comprises a control unit <NUM> designed to command the operation of the radiological imaging device <NUM>.

The control unit <NUM> is designed to command the radiological imaging device <NUM> with a scan during which the operating condition of the radiological filter <NUM> does not change and, in particular, the working configuration of the radiological imaging device <NUM> does not change.

In particular, the unit <NUM> can command a scan carried out with the radiological filter <NUM> in the first operating condition and, in particular, the radiological imaging device <NUM> in the first working configuration; and/or a scan carried out with the radiological filter <NUM> in the second operating condition and, in particular, the radiological imaging device <NUM> in the second working configuration.

The control unit <NUM> may comprise input means (such as a keyboard) designed to enable an operator to command the operation of the device <NUM>.

It may comprise output means (such as a screen) designed to enable an operator to monitor the operation of the device <NUM> and, in particular, to view acquisitions. The control unit <NUM> can be connected, conveniently so that it can be disconnected, to the anchor block <NUM> and, more specifically, to the stator part <NUM>.

The radiological imaging device <NUM> comprises a support structure for the anchor block <NUM>.

The radiological imaging device <NUM> can be mobile and, therefore, the support structure can comprise wheels or other similar elements designed to enable the entire radiological imaging device <NUM> to move along a walking surface.

The size of the radiological filter <NUM> is defined in relation to the emitter <NUM> and the detector <NUM>.

The length of the first sector <NUM> and, to be precise, of the first portion 2a depends on the position of the focal spot 11a and on the sensitive surface 21a and on the size of the sensitive surface 21a. In detail, the length of the first portion 2a (LF1) depends on: the distance between the focal spot 11a and the first portion 2a (DFF), the distance between the focal spot 11a and the sensitive surface 21a (DFP), and the length of the sensitive surface 21a (LS). More specifically, the length of the first portion 2a LF1 is defined by the following ratio: <MAT>.

The length of the second sector <NUM> and, to be precise, of the second portion 3a depends on the position of the focal spot 11a and of the sensitive surface 21a and on the shifting assembly <NUM>. More specifically, the length of the second portion 3a LF2 depends on: DFF, DFP, on the shifting range AP and, conveniently, on the LS and/or LF1. More specifically, the length of the second portion 3a LF2 is defined by the following ratio: <MAT>.

It should be noted that in this document the term distance (such as DFF, DFP) identifies extensions calculated substantially along the emission axis 10a; the term length (such as LF1, LF2, LS) identifies extensions calculated substantially in the direction perpendicular to the emission axis 10a and to the longitudinal axis 1a; and the term range (such as AP) identifies extensions calculated substantially along the shifting axis 22a.

The operation of the radiological filter <NUM>, emitter <NUM>, and, in particular, of the radiological device <NUM>, described above in structural terms, is as follows.

This operation defines an innovative radiological imaging procedure.

The radiological imaging procedure comprises a preparation step wherein the part to be analysed is located inside the analysis zone 30a.

The radiological imaging procedure may comprise a set-up step wherein the scan parameters are set; and at least one acquisition step wherein the scan is carried out.

In the set-up step, data relating to the patient part 1d to be analysed and, in particular, at least the length of the patient part 1d to be analysed are entered. The measurement of said length may be a direct measurement or may be indirectly derived from other parameters, such as height or weight.

The acquisition step comprises an evaluation sub-step wherein the control unit <NUM> determines the number of scans; and at least one scan sub-step wherein one of said scans is carried out. More specifically, the acquisition step comprises a scanning sub-step for each scan defined in the evaluation sub-step.

In the scanning sub-step, there is no change in the operating condition of the radiological filter, thus leaving the part of the first working surface 1b, which the x-ray beam 10a hits, unchanged during scanning. In particular, in the sub-step there is no change in said working configuration of the radiological imaging device <NUM>. By comparing the extension of the sensitive surface 21a with the measurements of the patient part 1d to be analysed, the control unit <NUM> determines the number of scans required.

If the length of the sensitive surface 21a is at least equal to the length of the patient part 1d to be analysed, the control unit <NUM> commands a single scan and then a single scanning sub-step.

If the length of the sensitive surface 21a is less than the length of the patient part 1d to be analysed, the control unit <NUM> commands multiple scans and then a scanning sub-step for each of said scans. The number of scans is proportional to the length of the sensitive surface 21a and, in particular, to the length of the sensitive surface 21a less a safety margin guaranteeing that the images overlap.

In the evaluation sub-step, the control unit <NUM> determines the number of scans and, for each scan, whether the radiological imaging device <NUM> works according to the first working configuration or according to the second working configuration.

After determining the number of scans, the control unit <NUM> defines, for each scan, the working condition of the radiological imaging device <NUM> and, in particular, whether it works according to the first or second working configuration. This choice can be made according to at least one type of radiological imaging and patient part 1d being scanned (whether a central or lateral part of the torso, etc.).

Usually, in the evaluation sub-step, the control unit <NUM> requires only one scan according to one of the working configurations. Alternatively, the control unit <NUM> requires two scans, one according to the first working configuration and one according to the second working configuration.

In the case of scans with different radiological imaging device <NUM> working configurations, the acquisition step comprises a configuration change sub-step between adjacent scanning sub-steps with different radiological imaging device <NUM> working configurations.

During the configuration change sub-step, the handler defines relative motion between the radiological filter <NUM> and at least one of either the collimator <NUM> and source <NUM>, by enabling a change of operating condition.

In addition, in this sub-step, the shifting assembly <NUM> handles the sensor <NUM> by changing its acquisition position.

At the end of the acquisition step, the radiological imaging procedure comprises an analysis step of one or more scans.

In the analysis step, the control unit <NUM> processes what has been acquired in one or more scanning sub-steps to obtain the desired radiological image.

The radiological filter <NUM>, the emitter <NUM> and, in particular, the radiological device <NUM> according to the invention achieve important advantages.

In fact, the radiological filter <NUM>, thanks to the subdivision of the first working surface into two different portions 2a and 3a, enables the filter to carry out acquisitions working either only as a flat filter or as a half bowtie filter combining the peculiarities of a flat filter and a bowtie filter.

As a result, the radiological filter <NUM> gives the emitter <NUM> and, in particular, the radiological imaging device <NUM> an advantageous flexibility without increasing their size, construction complexity, or production costs.

This aspect is further enhanced by the presence of a sensor <NUM> with different acquisition positions that makes it possible to define a radiological imaging device <NUM> characterised by a plurality of working configurations that can be selected according to requirements.

This advantage is maximised by the possibility of carrying out radiological imaging using different working configurations, each of which is optimal for the portion under examination. For example, it is possible to carry out radiological imaging, for example a radiography using the first portion 2a (i.e. the first operating condition) for the central zone of the patient 1d and a tomography using the second portion 3a (i.e. the second operating condition) for the outer portion (i.e. near the skin) of the patient 1d.

Claim 1:
An emitter (<NUM>) comprising
- only one radiological filter (<NUM>) designed for being passed through by an x-ray beam (10a); said radiological filter (<NUM>) comprising
o a longitudinal axis (1a);
o a first working surface (1b);
o a second working surface (1c) placed opposite said first working surface (1b) in relation to said radiological filter (<NUM>) so as to enable said x-ray beam (10a) to pass through said radiological filter (<NUM>) entering said radiological filter (<NUM>) and leaving said radiological filter (<NUM>) through said working surfaces (1b, 1c);
o a first sector (<NUM>) defining a first portion (2a) of said first working surface (1b), which is flat,
o a second sector (<NUM>) defining a second portion (3a) of said first working surface (1b) that is curved and complementary to said first portion (2a) in relation to said first working surface (3a), and said sectors (<NUM>, <NUM>) extend substantially parallel to said longitudinal axis (1a);
- a source (<NUM>) designed to emit an x-ray beam (10a) hitting said first working surface (1b); and
- a handler implementing relative motion between said radiological filter (<NUM>) and said x-ray beam (10a) by defining
o a first operating condition wherein said x-ray beam (10a) hits exclusively said first portion (2a) and
o a second operating condition wherein said x-ray beam (10a) hits at least said second portion (3a).