U.S. patent number 3,852,611 [Application Number 05/356,139] was granted by the patent office on 1974-12-03 for radiodiagnostic apparatus including a pivotable x-ray table.
This patent grant is currently assigned to Compagnie Generale De Radiologie. Invention is credited to Jean Cesar.
United States Patent |
3,852,611 |
Cesar |
December 3, 1974 |
RADIODIAGNOSTIC APPARATUS INCLUDING A PIVOTABLE X-RAY TABLE
Abstract
A radiodiagnostic apparatus including a pivotable table made up
from a panel for supporting a patient and a tomography device
articulated on a pendulum system, the assembly being mounted on a
vertical ring-shaped support rotatable about its own axis. The
tomography system and the patent supporting panel are suspended
substantially at their centers of gravity on carriages sliding
along two parallel circular arc-shaped arms perpendicular to the
vertical ring. A system for coordinating the movements of the
different mobile components of the apparatus makes it possible to
pivot the tomography system about the axis of the patient
supporting panel, which remains stationary in space.
Inventors: |
Cesar; Jean (Paris,
FR) |
Assignee: |
Compagnie Generale De
Radiologie (Paris, FR)
|
Family
ID: |
9098070 |
Appl.
No.: |
05/356,139 |
Filed: |
May 1, 1973 |
Foreign Application Priority Data
|
|
|
|
|
May 5, 1972 [FR] |
|
|
72.16106 |
|
Current U.S.
Class: |
378/27; 378/22;
378/196; 378/193 |
Current CPC
Class: |
A61B
6/04 (20130101); A61B 6/4441 (20130101) |
Current International
Class: |
A61B
6/00 (20060101); A61B 6/04 (20060101); G03b
041/16 () |
Field of
Search: |
;250/320,321,322,323,445,490,491,492 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lawrence; James W.
Assistant Examiner: Anderson; B. C.
Attorney, Agent or Firm: Cushman, Darby & Cushman
Claims
What is claimed is:
1. Radiodiagnostic apparatus for X-ray and, in particular,
tomographic examinations of a patient, including: a fixed base; a
ring-shaped support located in a vertical plane and mounted on said
base for rotation about a horizontal first axis coinciding with
that of the ring; two parallel circular arcuate arms extending
perpendicularly to and having one of their ends secured integrally
to said ring-shaped support at diametrically opposite locations
thereof, said arcuate arms being located symmetrically in relation
to the first axis and the centers of their radii defining a second
axis perpendicular to said first axis; a pair of first carriages
respectively mounted on said arcuate arms for simultaneous parallel
displacements therealong; first motor means for controlling said
displacements of said first carriages; rigid beam-shaped supporting
means parallel to said second axis fixedly interconnecting said
first carriage pair; a second carriage mounted on said beam-shaped
supporting means for independent translational displacements
therealong; fork-shaped supporting means fixedly mounted on said
second carriage having at their respective ends a pair of first and
second concentric shafts both coaxial with said second axis, said
first shaft pair being the outer one; panel-shaped patient
supporting means having ends respectively secured to said first
shaft pair for rotation therewith about said second axis; second
motor means carried by said second carriage for driving said first
shaft pair in rotation; third motor means carried by said second
carriage for driving said second shaft pair in rotation, said
second shaft pair being coupled to means for displacing said
panel-shaped supporting means in parallel to itself; a third
carriage mounted on said beam-shaped supporting means for
independent translational displacements therealong parallel to the
displacements of said second carriage; plate-shaped supporting
means mounted integrally with said third carriage and extending
away from said beam-shaped means to the opposite side relatively to
said fork-shaped means; an elongated supporting system mounted on
said plate-shaped means for omnidirectional pivoting about a plane
parallel thereto; an X-ray source and an X-ray image receiver means
respectively articulatedly mounted to both ends of said elongated
system for respective location on either side of a patient placed
on said panel-shaped supporting means, said X-ray source emitting
an X-ray beam whose axis always intersects with said second axis
and is incident on the center of said image receiver means; whereby
the center of gravity of the assembly carried by said first
carriage pair will always be located in the vicinity of said
beamshaped means.
2. Apparatus as claimed in claim 1, wherein said elongated
supporting system comprises: three lever rods journaled
respectively by means of joints allowing omnidirectional pivoting,
of the type of ball-or cardanjoints, on said plate shaped means,
said joints being located at the edges of a triangle in a plane
containing said second axis; a first and a second connecting means
articulated by means of omnidirectionally pivoting joints at the
respective ends of said levers, for maintaining said levers
parallel to each other whatever their inclination relative to said
plane containing said second axis; a first rigid arm member
integral with said first connecting means and extending towards
that side of the beam-shaped means where said panel-shaped means is
located for carrying said X-ray image receiver; a
paralellogram-type structure including: a second rigid arm member
integral with said second connecting means and extending towards
that side of said beam-shaped means where said panel-shaped means
is located; stub portions prolongating at least two of said three
levers above said second connecting means by a predetermined
length; a third elongated arm member omnidirectionally articulated
on at least two of said stub portions; a rigid rod-shaped member of
said predetermined length and omnidirectionally articulatedly
connecting together the free ends of said second and third arm
members so as to always be oriented in parallel to said levers;
said X-ray source being integrally mounted on said rod-shaped
connecting member so as to always direct said X-ray beam to
intersect with said second axis; whereby said X-ray source is
displaceable along a sphere and the X-ray beam within a cone whose
apex constituting the center of said sphere always lies on said
second axis.
3. Apparatus as claimed in claim 2, further comprising means for
controlling the pivoting said lever rods and wherein said means for
controlling includes: third rigid connecting means identical and
parallel to said first and second ones and located at a
predetermined distance from said plane containing said second axis;
a third arm member integral with said third connecting means and
having a free end protruding therefrom towards the opposite side to
that of said first and second arm members, said free end carrying a
bearing; a threaded shaft and nut assembly lodged on a flat
supporting plate, said threaded shaft being driven in rotation by
means of fourth motor means carried by said flat plate and said nut
carrying a third shaft engaging in said bearing; a fourth shaft
extending from and perpendicularly to said plate-shaped supporting
means for rotatably carrying said flat plate; and fourth motor
means carried by said plate-shaped means for rotating said flat
plate, whereby to enable said X-ray source be displaced in any
desired direction on said sphere surface such as along circular
arc, a circle or a spiral.
4. Apparatus as claimed in claim 2, wherein a second auxiliary
X-ray source is rigidly mounted on said plate-shaped support for
emitting a second X-ray beam whose axis intersects with said second
axis at the apex of said cone.
5. Apparatus as claimed in claim 1, wherein said first motor means
for controlling the displacement of said first carriage pair along
said two arcuate arms include a polygonal shaft for interconnecting
said first carriage pair and for synchronising its movements.
6. Apparatus as claimed in claim 5, wherein said first outer shaft
pair for rotating said panel-shaped supporting means respectively
carry a pair of first sprockets; said second motor means having a
fifth shaft carrying a second sprocket; a first endless chain
meshing with said first and second sprockets; and wherein said
second motor means is carried movably on said fork-shaped means in
a first pair of slides, the displacement of said second motor means
along said first slide pair being controlled by means of a further
threaded shaft journalled on said fork-shaped means and a nut
engaging with said second motor means, said further threaded shaft
being coupled to said polygonal shaft by means of a second endless
chain and a pair of third sprockets, whereby said first shaft pair
carrying the panel-shaped supporting means is rotated synchronously
with the displacement of the first carriage pair along the arcuate
arms so as to maintain said patient in a fixed position in space
whatever the position of said first carriage pair along said
arcuate arms.
7. Apparatus as claimed in claim 6, wherein said second inner shaft
is driven by said third motor means by means of a pair of fourth
sprockets and an third endless chain, said fourth sprockets being
of the same size a said first sprockets; said third motor means
being freely movably mounted on said fork-shaped means for
displacement along a second pair of slides parallel to said first
pair of slides and connected to said second endless chain, whereby
to render said second shaft pair stationary with respect to said
first shaft pair, on the one hand, when said first carriages are
displaced along said arcuate arms and, on the other hand, when said
first shaft pair is rotated by means of said second motor means.
Description
The present invention relates to radiodiagnostic apparatus having a
pivotable X-ray table and concerns, in particular, such as those
used as patient supporting means in a tomography apparatus.
Radiodiagnostic apparatus of this kind has become widely used and
is well known per se. They essentially include a table panel or
plate, used to support the patient, and by a supporting structure
rotationally carried for example by a ringshaped support located in
a vertical plane. This disposition enables the panel to occupy any
position between the horizontal and the vertical, in both senses.
These devices furthermore generally comprise a mobile and pivotable
column, utilised as a support for X-ray emissive devices at one end
and for radiological image receivers at the other. The column
and/or panel are moveable in the longitudinal direction of the
panel in order to make it possible to irradiate any required point
upon the latter.
Apparatus of this kind has a certain number of drawbacks and it is
the object of the present invention to overcome these.
The proximity of the column to the patient, creates in the latter a
sense of anxiety which can result in movements of reaction at the
time of exposure, while the column is pivoting (tomography), so
that the quality of the X-ray picture is poor.
The various assemblies making up the X-ray apparatus, are almost
always located at the same side of the main support, thus creating
an unbalanced or overhung system which gives rise to problems of
design as far as the production of a vibrationfree system is
concerned. Moreover, because of distortions created by this
overhung arrangement, the changes in the orientation of the table
or of the pendulum or of both simultaneously, produce misalignment;
it is well known, for example, that it is impossible to pivot the
X-ray tube and image receiver system in just any direction, without
losing image centering.
In prior art apparatus, tomography picture obtained by pivoting the
column tended not to be perfectly sharp because the X-ray source
and the receiver were displaced along two parallel straight lines
or planes, and thus their relative distances varied with their
angular position. In an apparatus in accordance with the invention,
source and receiver are displaced over a sector of sphere whilst
the beam emanating from the source is always directed towards the
center of the sphere, which center becomes therefore the center of
tomography. The X-ray beam is consequently always located inside a
cone whose apex is defined by this tomography centre.
The determination of the tomography plane, wherein the axis of the
shaft pivotably carrying the column is located, requires
observation along an axis perpendicular to the axis in which
tomography is to be carried out. In the case of the prior art X-ray
diagnostic apparatus, this resulted in displacements of the panel
and/or the source which at the very least meant a loss of time and
a certain amount of fumbling, quite apart from the nuisance caused
to the patient. The arrangement of the novel apparatus makes it
possible to position a second X-ray source, whose beam is
permanently directed towards the tomography centre, perpendicularly
to the axis of the above indicated cone, thus making it possible to
simultaneously carry out observations along two mutually
perpendicular axes and to locate the desired tomography plane in a
highly accurate fashion. The positioning of said second source is
made possible, with the novel apparatus in accordance with the
invention, by the fact that there is no support or component of any
kind to interfere with the beam, whatever the configuration
thereof.
Moreover, the novel apparatus makes it possible to irradiate the
patient at any angle of incidence although he or she remains
horizontal or immobile.
According to the invention there is provided, a radiodiagnostic
apparatus for X-ray and, in particular, tomography examinations of
a patient, including: a fixed base; a ring-shaped support located
in a vertical plane and mounted on said base for rotation about a
horizontal axis; two parallel circular arcuate arms extending
perpendicularly to and mounted integrally with said ring-shaped
support, said arcuate arms being located symmetrically in relation
to the center of said ring-shaped support and the centers of their
radii defining a first axis perpendicular to said horizontal one;
two first carriages respectively mounted on said arcuate arms for
simultaneous translational displacements therealong; first motor
means for controlling said displacement of said carriages; rigid
beam-shaped supporting means parallel to said first axis for
fixedly interconnecting said first carriages; a second carriage
mounted on said beam-shaped supporting means for independent
translational displacement therealong; fork-shaped supporting means
fixedly mounted on said second carriage having at their respective
ends a pair of first and second concentric shafts both coaxial with
said first axis, said first shaft being the outer one; panel-shaped
patient supporting means mounted on said first shaft for rotation
therewith about said first axis; second motor means carried by said
second carriage for driving said first shaft in rotation; third
motor means carried by said second carriage for driving said second
shaft in rotation, said second shaft being coupled to a mechanism
known per se for displacing said panel-shaped means in parallel to
itself; a third carriage mounted on said beam-shaped supporting
means for independent translational displacement therealong;
plate-shaped supporting means mounted integrally with said third
carriage and extending away from said beam-shaped means to the
opposite side relatively to said fork-shaped means; an elongated
supporting system mounted on said plate-shaped means for
omnidirectional pivoting about a plane parallel thereto; an X-ray
source and an X-ray image receiver means respectively articulatedly
mounted to both ends of said elongated system for respective
location on either side of a patient placed on said panel-shaped
supporting means, said X-ray source emitting an X-ray beam whose
axis always intersects with said first axis and is incident on the
center of said image receiver means; whereby the center of gravity
of the assembly carried by said first carriages will always be
located in the vicinity of said beam-shaped means.
The invention will be better understood and other of its features
and advantages rendered apparent, from the following description
and the accompanying drawings, wherein:
FIG. 1 is a front elevational view of the novel X-ray
apparatus;
FIG. 2 is a sectional side elevational view of the apparatus in the
position corresponding to frontal X-ray projection;
FIG. 3 is a plan view of the apparatus when in horizontal
position,
FIG. 4 is a lateral view of the arcuate track 11 with its
supporting carriage;
FIG. 5 is a sectional view of the supporting means;
FIG. 6 is a side elevational view of the apparatus in the
tomography configuration.
In FIGS. 1 and 2, a metal ring 1, vertically supported by a set of
rollers 2 upon which it can roll, can be seen. These rollers are
journalled to the floor 3 by means of a frame or wall which has not
been shown. The rotation of the ring 1 on the rollers 2 is
controlled by a fixed chain, shown in broken line, winding around a
sprocket 4 driven by a reduction gear box and a motor 5. The ring 1
can thus rotate both clockwise and anticlockwise, and can be
displaced through an amplitude in excess of half a turn
(180.degree.) to either side of a central position.
The assembly of the apparatus mounted on this ring 1 by means of
two circular arcuate components 11 subtending an angle of around
160.degree.. These arcs 11 are attached in perpendicular
relationship to the ring 1, parallel to each other, by means of two
mounting components 51 and 52 located symmetrically with respect to
the center of the ring and integral therewith. The mounting
components 51 and 52 fixedly carry the arcs 11, which, in turn
slidably carry carriages 7 (FIG. 4).
In said FIG. 4, a carriage 7 slidably mounted, in a manner known
per se, on the arc 11 by means of rollers 8, can be seen, the
displacement of the carriage 7 along the arc being controlled by a
fixed chain, marked in broken-line and winding about a toothed
sprocket 9 driven by motor and reduction gear assembly and
journalled to the carriage 7. The two carriages 7, respectively
sliding on each of the arcs 11 are connected together, on the one
hand, through two beams 12 and, on the other hand, through a
polygonal shaft 10, one end of which has been shown in square form
in FIG. 4, passing through the sprocket 9. In this fashion, the two
sliding carriages 7 are secured to one another and are at all times
located at homologous positions on each of the arcs 11, because of
the fact that the sprockets 19 controlling their displacements
themselves have identical positions due to the shaft 10 which links
them.
Along these connecting beams 12, there are displaced two carriages
13 and 22 (FIG. 3), the carriage 13 carrying, towards the interior
of the ring 1, a column assembly which will be described
hereinafter, and the carriage 22 carrying, towards the opposite
side, a forked-shaped support 21 for supporting a panel for the
patient or table top 23. These two carriages 13 and 22 are moveable
along the beams 12 independently of one another so that the source
located substantially at the center of the carriage 13 can
irradiate one or the other of the two ends of the panel 23.
Considering FIG. 2, a plate 24 can be seen, which is integrally
fixed to the carriage 13 and which, by means of bosses 25
containing ball joints or the like, carries three levers 14. The
structure of the plate 24 is such that the plane defined by said
three ball joints passes through the center of the circular arcs
11. The three levers 14 are maintained parallel with one another
and hinged together in three planes made up by means of rigid links
schematically represented at 16, 17 and 18. The rigid structures 16
and 17 are extended throughout and towards the other side of the
ring 11, i.e., to the side opposite to the support 24, and carry
the receiver 28 (fluoroscopic screens, cameras and/or image
intensifier with accessories) and the main X-ray source 15. The
X-ray source 15 is integrally fixed to a rigid link schematically
illustrated at 26, which is coupled in an articulated manner to at
least two levers 14 through a rigid link 27 and the extension of
link 16. It would be seen that when the levers 14 are inclined, any
point on the links 16 and 17 will move over the surface of a
sphere, the center of this sphere being located in the plane
defined by the three points of articulation (25) of the levers to
the plate 24.
The source 15 fixed to link 26 is maintained parallel to the levers
14 by means of a structure 27 attached by ball joints to at least
two of these. It will be seen that the structure 26 is at all times
aligned with a fixed point in relation to the support 24. The
extensions or suspension arms of the structure 16 and 17, have a
length such that the centres of the spherical sectors described by
the source 15 on the one hand and the receiver on the other, are
coincidental with one another and located upon the straight line
joining the centers of the circular arcs 11. The source 15 fixed to
the structure 26, is therefore permanently trained on a fixed point
in relation to the support 24, and situated on said same straight
line. This point will in all cases be the tomography centre.
The structure 18, articulated to the same three levers 14, is
connected by a rigid extension 29 to the tomography control plate
of known kind. It comprises a threaded rod 30 axially driving a nut
carrying a shaft hinged to the rigid extension 29. The rod 30 is
journalled to a plate 31 which can pivot about a pin perpendicular
to and fixed to the plate 24. An electric motor 32 attached to the
plate 31 drives the threaded rod 30. On the other hand, the plate
31 carrying the rod 30 is itself rotated by a motor 33 about the
aforementioned pivot of support 24. It will be seen that by these
means, through coordination of the movements of the motor 32 and
33, the link 18 and consequently the source 15, can be imparted an
absolute motion of any kind over the surface of a sphere, which
motion can for example be a circular arc in any desired direction,
a circle, a spiral etc., while the source 15 remains at all times
directed upon a fixed point in relation to the support plate 24.
The X-ray beam is therefore at all times displaced within a cone
the centre of which is fixed in relation to the plate 24 and is
located upon the straight line joining the centres of the arcs 11.
The angles subtended at the apex of the cone is equal to the angle
of inclination at which the levers 14 are capable.
The carriage 13 furthermore carries an auxiliary source 20 on an
arm 19. The beam from this source is directed permanently on to the
apex of the cone of oscillation of the main source 15,
perpendicularly to the axis of said cone. Considering FIGS. 2 and
3, it will be seen that the beam from the source 20 passes, on the
one hand, between two articulated levers 14, and, on the other
hand, between the two beams 12. Thus, there is no dead angle as far
as this beam is concerned (nor is there any in respect of the beam
produced by the source 15) at any position of the carriages 7 and
13.
A forked-shaped support 21 is fixed at the patient support plate
side to the second carriage 22, which slides along the connecting
beams 12. This support 21 carries the patient support panel 23
through two coaxial pivots 34 and 35 whose purpose will be
explained hereinafter. The axis of suspension of the panel, i.e.,
that of pivots 34 and 35, is coincidental with the straight line
joining the centers of the two arcs 11. The result is that
displacements of the carriages 7 along the arcs 11, produces
displacement of the fork 21 and of the support 24 and, with the
latter, displacement of the source 15 of the receiver 28, in a
rotational manner about an axis which is fixed in relation to the
arcs 11. In FIG. 2, a broken line has been used to indicate the
respective positions 121, 151 and 281 of the carriages 7, source 15
and receiver 28, after displacement of said carriages to the ends
of the arcs 11.
However, although the carrier pivots 35 of the patient support
panel (FIG. 5) remain stationary in space during displacements of
the carriages 7 along the arcs 11, they nevertheless undergo
rotation. It is necessary to avoid this rotation by counteracting
it so as to maintain the panel 23 parallel to itself during
displacements of the carriages 7 along the arcs 11. Moreover, the
panel 23 must be capable of being displaced perpendicularly to its
own plane so that the tomography plane can be selected (and
varied). It has been seen that the determination of the desired
tomography plane is greatly aided by the utilisation of the
auxiliary source 20 the beam from which is always directed onto the
center of the arcs 11 perpendicularly to the axis of the cone
within which the beam produced by the main source 15 can be
displaced. It is likewise important that during displacements of
the carriages 7 along the arcs 11, not only does the panel 23
remain parallel to itself, but neither should its position in
relation to the center of tomography which is fixed, vary. This
maintaining of the panel 23 in a fixed position in space, both in
rotation and translation, during displacements of the carriages 7,
is obtained by means of a mechanical arrangement schematically
shown in FIG. 5.
At 21, the support of forked shape for carrying the panel 23 upon
which the patient lies, can be seen. The two ends of the fork each
carry two concentric shafts 34 and 35, the shafts 34 supporting the
frame of the panel (not shown) and the shaft 35 controlling the
displacement of the panel in the direction perpendicular to its own
plane, by means of a known mechanism (likewise not shown). The
rotation of the shaft 34, and consequently the panel, is controlled
by a motor and reduction gear set 37, to which said shaft is
connected through a chain 46 meshing with the sprockets 44. The
shaft 35 is rotated in the same manner by the motor and reduction
gear set 38, driving the chain 37 meshing with the sprockets 45
which have the same diameter as those 44. The two sets 37 and 38
are assembled on slides or the like and can be displaced along the
support 21, displacing the chains 46 and 47, which respectively
control the rotation of shafts 34 and 35, as they do so.
The translation of the set 37 is controlled by the displacement of
the carriage 7 along the arcs 11, with the help of a threaded shaft
39 operating a nut 40 fixed to the set 37. The shaft 39 is driven
by means of a chain through the sprocket 41, whose position is
fixed in relation to the support 21 and which slides along the
polygonal shaft 10 connecting the sprockets 9 of the two carriages
7 (FIG. 4) during translational movements of the latter. The
dimensions of the various sprockets and the threading of the shaft
39, are designed so that the displacement of the carriages 7 along
the arcs 11, produces displacement of the set 37 and consequently
of the chain 46 controlled by it, by an amount and in a direction
such that the shaft 34 in relation to the support 21 performs a
rotation equal and opposite to the rotation of the forks of support
21 during displacement of the carriages 7 along the arcs 11.
The shaft 35 controlling translation of the panel 23
perpendicularly to its own plane, should not rotate in relation to
the panel (and therefore in relation to the shaft 34), either
during this movement of the carriages 7 or when the operator
initiates rotation of the panel 23 by means of the motor and
reduction gear set 37. This double effect is obtained by fixing the
set 38 (mounted on slides like the set 37) to the chain 46
controlling rotation of the shaft 34. To do this, the chain 46 is
attached to the set 38 by means of a wedge arrangement 42. It will
be seen that in these circumstances, on the one hand, when the set
37 is displaced by the movement of the carriages 7 over the arcs 11
and, on the other hand, when the set 37 is set into operation to
manipulate the panel 23 through the shaft 34, the chains 46 and 47
are displaced by the same amount, causing the shafts 34 and 35 to
execute the same angle of rotation since the sprockets 44 and 45
have the same diameters, in other words, during these two
operations, the panel 23 remains parallel to itself and executes no
displacement perpendicular to its own plane since the shaft 35
remains stationary in relation to the shaft 34.
The panel 23 furthermore comprises a lateral translation device,
this being a device well known per se and not having been
illustrated here since it does not affect the invention.
It will be seen that the aforedescribed arrangements of the
apparatus result first of all in better balancing of the system.
The moving weights carried by the carriages 7 are in other words
distributed to either side of said carriages: panel and patient at
one side, assembly of sources and receiver, at the other. The
improvement in balance is achieved not only in relation to the
beams 12, but also in relation to the suspension of the entire
system on the ring 1, which results in a simplification of the
structure and lower weight, a reduction in distortion and
improvement of motion which becomes substantially vibrationless.
Moreover, the patient no longer has the oscillating levers for the
tomography operation close to his sides, these being separated from
him by the beams 12. The various panel supports occupy fixed
positions in relation to the sources and receivers so that there is
no longer any dead angle to be avoided when it is desired to change
the angle of incidence. The preparatory work for X-ray examinations
is therefore much simplified and operation become much faster.
Another advantage of this arrangement of the supports is that it
makes it possible to install the second source 20, the usefulness
of which has been described hereinbefore. Finally, the system for
coordinating the movements of the panel supporting the patient
makes it possible to give the two beams all the possible angles of
incidence without modifying the position of the panel and the
tomography plane.
The device for carrying the patient supporting panel can be
designed so that it can be removed and replaced by another
equivalent one or one having different characteristics. These
characteristics may be ones pertaining to its type and shape. The
panel can be replaced by an interchangeable device equipped with
one or two lengthwise members carrying an articulated panel which
may for example be turned into a chair for neurological
applications.
This X-ray apparatus is also particularly well suited for
neurological examinations because the beam and the patient can be
pivoted by means of the main ring, through at least 180.degree. to
either side (gas encephalography) without changing there relative
positions.
Finally, it is possible with this equipment to use elements other
than the panel hereinbefore described, such for example as chairs,
and horizontal tables with moving panels. These elements can be
fixed or mobile on the floor, or to that matter be fixed to the
apparatus.
* * * * *