A METHOD OF PERFORMING X-RAY EXAMINATION OR LIKE EXAMINATIONS, AND A CASSETTE HOLDER FOR USE WHEN CARRYING OUT THE METHOD

Abstract: In connexion with X-ray or like examination there is used a cassette holder arrangement which is carried by a frame structure (7) by means of pivotal arms (4) which are capable of being swung in the horizontal plane, such as to adjust the position of the cassette in the vertical direction. The arrangement enables pictures to be taken of a sitting patient in mutually perpendicular directions, with the aid of a radiation source (2). The cassette holder (3) can be swung between the exposure positions in a circuit path around the sitting patient, by activation of one of the arms (4). To this end there can be used a parallel linkage (11) which is operative to guide the cassette holder during this pivotal movement. The cassette holder is fixated relative to one of the arms (4), by means of a locking device (8), which is released when wishing to pivot the cassette holder. The invention also relates to a cassette holder arrangement of the aforedescribed kind.

Description: A method of performing X-rav examination or like examinations, and a cassette holder for use when carry¬ ing out the method rigid of Invention The present invention relates to a method for carrying out X-ray examinations or like examinations with the aid of a cassette-carried receptor intended to receive radiation from a radiation source which is adapted to take two or more exposures. The invention also relates to a cassette-holder device for carrying out such diagnostics. Particular problems are encountered, both on the part of the patient and on the part of the personnel, when subjecting to X-ray examination elderly patients, who are often seriously handicapped, and other categories of patients who have difficulty in leaving their hospital bed on their own feet, e.g. because of serious illness or injury sustained in a traffic accident for instance. In some cases it is necessary to X-ray a patient at the bedside with the patient in bed, requiring the image receptor to be placed between the patient and the mat¬ tress, with all the drawbacks associated therewith. Bedside examinations are carried out both in intensive care wards, using portable X-ray equipment, and in the X-ray department itself. The majority of patients who are either too ill or too weak to stand unsupported or unaided are, nevertheless, able to sit on the edge of the bed. Although some lung X-ray frames will permit frontal pictures to be taken from the bed, no room is available for side pictures, since the lung frame is normally placed adjacent a wall which makes it impossible to turn the bed through an angle of 90° . 5. BacHgrpunά Art Various methods and cassette holders have been proposed with the intention of facilitating the X-ray examination 0 of handicapped patients. For instance, US-A-4,468,803 (Ronci) describes a cassette-holder suspension system which enables the cassette holder to be rotated in mutually different 5 planes so as to enable different types of exposures to be taken. This known system include a clamping device which is manouvered with the aid of knobs and by means of which the cassette holder and carrier means can be brought to different desired positions, for instance 0 adjacent a table. Vertical adjustments can be made only by releasing the clamping device and mounting said device at the height desired. One drawback with this known apparatus is that it is heavy to manipulate, particularly when moving the apparatus between different 5 positions of application. US,A,2 651 725 (HcFarland) describes a similar cassette holder device which can be mounted in different posi¬ tions adjacent a patient's bed. Adjustments require the 0 manipulation or activation of a relatively large number of clamping or tightening members which - as a rule - are located at a considerable distance from one another. Other examples of the known art are found described in US,A,3 795 815 (Weinstock et al), which, teaches a cas¬ sette holder fitted to a wheel chair and SE,B,354 728 (Tidestrδm et al) which teaches a freely transportable device for holding an X-ray film cassette in freely 5. variable positions. The majority of known arrangements and apparatus have the drawback that a cassette provide .with receptor and mounted in a cassette holder can be centered in relation 0 to the radiation source concerned only with great dif¬ ficulty. For instance, it is difficult to position the radiation source in relation to the image receptor so that radiation emitted from said source will pass at right angles to the receptor. Consequently, there is an 15 obvious risk that the images taken will be rf un¬ satisfactory and need to be retaken, with subsequent exposure of the patient to unnecessary high dosages of radiation. 20 These difficulties are accentuated when a grid or screen is placed in the vicinity of the cassette holder - as is normally the case. An important prerequisite with res¬ pect to satisfactory images or photographs is that the screen extends perpendicularly to the radiation beam in ?5 one plane. Summary of the Invention The object of the present invention is to provide a 30 method and an arrangement which will avoid the majority of the aforesaid drawbacks encountered with known methods and arrangements in respect of the majority of handicapped patients who are unable to leave their beds unaided but who, nevertheless, are able to assume a 35 sitting position in bed, possibly with the assistance of attending personnel. The inventive method is of the kind defined in the preamble of the following claim 1 and is characterized by the features set forth in the characterizing clause of said claim. The inventive method enables various types of images to be taken without noticeable discomfort to the patient and without impediment to movement of the cassette holder between different, relevant setting positions. Precise centering of the receptor in relation to the radiation source is also achieved, and only negligible adjustments to the position or attitude of the patient are needed, these adjustments being easily managed by the attendant personnel. The small positional changes required are more related to exposures to be taken with patients of different sizes. Another small movement normally required of a patient is related to the necessity of taking an exposure with the patient leaning slightly forwards. The patient can straighten his/her back slightly, when the cassette holder is passed in the aforesaid circuit path between the various exposure positions. The automatic guiding of the cassette holder can be effected with the aid of a parallel linkage mechanism which is mounted in an appropriate manner in relation to the cassette holder and the attachment of said pivotal arm or arms and which will provide the movement desired. The cassette-holder may be self-locking on the end of the pivotal arm or arms, i.e. so as to ensure that the position to which the cassette holder is adjusted will remain unchanged until a force of given value is applied. It is preferred in practice, however, that the cassette 5. holder is fixated in a desired position of adjustment with the aid of a finger-operated fixating device which is released prior to commencement of said pivotal movement. 0 According to a second aspect, the invention also relates to a cassette-holder device for X-ray or like examin¬ ation, said cassette-holder device having the charac¬ teristic features set forth in the following Claim 3. 15 An exemplifying embodiment of the invention will now be described with reference to the accompanying drawings. Brief description of the drawings 20 Figure 1 is a perspective view of a cassette-holder device constructed in accordance with the invention, and shows the device in coaction with a radiation source for the exposure of an X-ray picture on a bed-sitting patient. 2£ Figure 2 is a view from above of the holder device illustrated in Figure l. Figure 3, finally, is a perspective view of a holder 30 device and radiation source according to Figure 1 when taking a side-exposure of the patient, i.e. in a direc¬ tion which is 90" to the direction shown in Figure 1. Description of Preferred Embodiments !__> The reference numeral 1 in the various Figures of the drawings identifies a cassette-holder device for X-ray or like examination. The cassette-holder device is in¬ tended for coaction with a radiation source 2 carried by jj> a telescopic, ceiling-mounted frame 10. The cassette-holder itself is referenced 3 and comprises a so-called potter or bucky box which is intended to receive replaceably and to center with receptor-equipped 10 cassettes of mutually different sizes. The cassette holder 3 is mounted on an upper and a lower pivotal arm 4, each of said arms being pivotally con¬ nected at one end thereof to a respective holder element 15 5 extending from a central slot 7a in a column structure 7. The holder elements 5 form part of a counter-balanced hoist arrangement which enables the cassette holder 20 device to be positioned in the vertical direction. The outer ends of respective pivotal arms 4 are con¬ nected to the cassette holder, approximately in the centre of said holder, by means of a pivot axle 4b. 25. The cassette holder can be releasably locked in desired positions relative to the arms 4, with the aid of a locking device in the form of a knob 8. 30 Extending perpendicularly from the lower side of the cassette holder 3 is a shoulder 6 which is connected to the lower element 5 projecting from the column structure 7, by means of a parallel linkage 11. The parallel linkage 11 is connected to respective elements 5 and 6 35 via pivot axles 5a and 6a respectively. The parallel 2 linkage 11 therewith forms a parallel mechanism which is operative to guide the cassette holder in a pre¬ determined path upon activation of one of the pivotal arms 4 between the two positions illustrated in chain 5. lines in Figures 1 and 2 and forming an angle of 90 * with one another. The position of the cassette holder illustrated in Figures l and 2, where said holder is parallel with the 0 wall, can be said to constitute a "parking position", i.e. a position in which the cassette holder is out of the way. A conventional exposure position for taking a photograph 5 of the lungs of a sitting patient 15 is shown in full lines in Figures 1 and 2. The patient is shown seated in a forwardly inclined position. The cassette holder is then moved to the position illu- 0 εtrated in Figure 3 for taking a side picture, by acti¬ vation of the arm 4. In doing so, the locking knob 8 is first released, so that the arm 4 can be swung. The parallel linkage mechanism 11 assists in enabling the cassette holder to be moved in a circuit path around the 5 patient 15, to the position illustrated in Figure 3, i.e. without discomfort to the patient. As illustrated in Figure 3, the cassette holder is provided with a handle or hand grip 16. The patient jβ. grips the handle, as shown in Figure 3, so that the patient will be brought to a correct position in rela¬ tion to the image receptor concerned, more or less automatically. It may be necessary, in this respect, for the patient to adjust his/her position slightly, in 5 order to enable a picture of the best possible quality to be taken. The X-ray operator assists the patient in making these movements, which can therewith be performed without undue difficulty. When the cassette holder has been brought to the posi¬ tion illustrated in Figure 3, the knob 8 is turned so as to lock the cassette in its adjusted position. The handle 16 is removably attached to the cassette holder, and can be removed when not needed.

Claims: Claims 1. A method for performing X-ray or like examination 5. with the use of a cassette-carried receptor intended to receive radiation from a radiation source which is set to take two or more pictures of a patient in exposure positions in at least approximately perpendicular direc¬ tions, e.g. a back and/or front picture and a side 10 picture, said cassette being detachably received in a holder which is carried by a frame structure and which can be adjusted positionally in a vertical direction, c h a r a c t e r i z e d by pivotally mounting the cassette holder on the end of one or more arms which 15 can be swung in the horizontal plane; and activating said pivotal arm or arms such as to move the cassette holder between the various exposure positions while automatically guiding the holder in a circuit path past the sitting patient. 20. 2. A method according to Claim 1, c h a r a c¬ t e r i z e d by releasably locking the cassette holder to the pivotal arm in said exposure positions. ?5 3. A cassette holder device for X-ray or like examin¬ ation with the aid of a cassette-carried receptor in¬ tended for receiving radiation from a radiation source (2) , said cassette being removably located in a holder (3) which is carried by carrier means (4) on a frame 30 structure (7) for vertical adjustment in relation to said frame, c h a r a c t e r i z e d in that the carrier means includes at least one arm (4) which can be pivoted in the horizontal plane and which is pivotally connected at one end thereof to the cassette holder (3) 35 so that when taking pictures in at least approximately perpendicular directions on a sitting patient (15), e.g. a back and/or front picture and a side picture, it can be moved between the exposure positions in a circuit path past the patient. 5. 4. A cassette holder device according to Claim 3, c h a r a c t e r i z e d in that the cassette holder (3) is carried by an upper and a lower arm (4) which engage approximately centrally with two mutually oppos- 10 ing sides of the cassette holder (3). 5. A cassette holder device according to Claim 4, c h a r a c t e r i z e d by means (8) for releasably locking the cassette holder in relation to one of the 15 arms (4). 6. A cassette holder device according to any one of Claims 3-5, c h a r a c t e r i z e d by a parallel linkage (11) which is operative to guide the cassette 20 holder (3) in said path when the arm (4) is pivoted. 7. A cassette holder device according to any one of Claims 3-6, c h a r a c t e r i z e d by a preferably detachably mounted element (16) on the cassette holder 25. by means of which the cassette holder can be gripped by said patient while an exposure is taken.

Inventors: OHLSON CARL-ERIC, OHLSON, CARL-ERIC
Applicants: AO MEDICAL PRODUCTS AB
Application year: 1990
Main classification: G03B42
IPC codes: A61B6, G03B42