Magnetic resonance imaging diagnosis apparatus having mat for use with small body

A magnetic resonance diagnosis apparatus having a diagnosis mat by which the position of the surface coil is accurately confirmed. The magnetic resonance imaging diagnosis apparatus includes a gantry for enclosing a biological body so as to provide an imaging area; a mat portion having a slot therein in a lateral side thereof wherein the mat portion is provided above a tabletop that is movable into and out of the gantry; and surface coil for applying electromagnetic waves to the biological body, and which is slidably inserted to the slot of the mat portion so that a position of the coil means is accurately indexed and observed.

BACKGROUND OF THE INVENTION 
1. Technical Field 
The present invention relates to a diagnosis mat and a infant-use mat under 
magnetic resonance imaging (MRI) which supports a biological body to be 
examined by an MRI diagnostic apparatus. 
2. Background Art 
In recent years of active development for medical diagnosis apparatus, 
there has been often utilized a magnetic resonance (MR) diagnosis 
apparatus in which a biological body under medical examination is imaged 
without being operated on or being cut out. In the magnetic resonance 
diagnosis apparatus, the biological body is placed on a tabletop and is 
transported into a gantry so that the biological body is photographed in a 
photographing region of the gantry. Therefore, the body to be examined 
must be at a standstill position. 
While the requirement for the body to be at a stationary position is not 
difficult to be achieved for grown-up people, however, it often creates 
difficulties among infants or small children. Thus, there is now used a 
mat to support a patient such as the infant and small child. 
FIG. 7 shows such a mat to be used for the MR apparatus. In FIG. 7, a 
plurality of belts 3 (four belts) are attached to a side of the mat and 
there are provided four buckles 2, on other side, to fasten respective 
belts 3. 
Referring still to FIG. 7, the patient placed on the mat 1 is firmly 
supported by the belts 3 and the buckles 2. In order that a nuclear 
magnetic resonance (NMR) signal is received from a desired position of the 
patient, part of the mat 1 is a hollow and a short side of the mat 1 has 
an opening so that a surface coil 5 can be inserted inside of the mat 1. 
The surface coil 5 is fixed to a tray 4 and can be pulled out by a pullout 
rod 6. In other words, the position of the surface coil 5 can be adjusted 
by pulling and inserting the pullout rod 6. 
However, in the magnetic resonance apparatus as shown in FIG. 7, the 
surface coil 5 is inserted into a longitudinal direction of the mat 1. 
Therefore, the position of the surface coil 5 can not be visually 
confirmed, so that the position of the surface coil 5 is determined based 
on length of the pullout rod 6 inserted. Therefore, there is a drawback 
where the position of the surface coil 5 can not be accurately set without 
providing a scale. 
Moreover, when a patient such as infant or small child is examined and 
imaged, an anesthetic is sometimes required to avoid undesired movement by 
the patient. Moreover, a few piles of towels need be placed under the 
patient in order to adjust the height to obtain an appropriate imaging 
region thus taking much time. 
Accordingly, since the surface coil 5 is inserted from the longitudinal 
direction of the mat 1, the position of the surface coil 5 can not be 
accurately confirmed. Moreover, when the infant or small child is imaged 
by the MR apparatus, the patient goes through physical pain by taking an 
anesthetic or the like and many efforts are required to properly adjust 
the height and position of the patient. 
SUMMARY OF THE INVENTION 
In view of the foregoing drawbacks, it is therefore an object of the 
present invention to provide a magnetic resonance diagnosis apparatus 
having a diagnosis mat by which the position of the surface coil is 
accurately confirmed. 
Another object of the present invention is to provide a small-body-use mat 
for magnetic resonance apparatus to facilitate imaging of the small 
biological body to be examined. 
According to one aspect of the present invention, there is provided a 
magnetic resonance imaging diagnosis apparatus in which a biological body 
to be examined is placed over a tabletop thereon, in which the apparatus 
comprises: a gantry for providing an imaging area; a mat portion having a 
slot therein in a lateral side thereof, the mat portion being provided 
above the tabletop that is movable into and out of the gantry; and radio 
frequency coil means for applying electromagnetic waves to the biological 
body, and which is slidably inserted to the slot of the mat portion so 
that a position of the coil means is accurately observed and aligned. 
According to another aspect of the present invention there is provided an 
magnetic resonance imaging diagnosis apparatus, including: a mat portion 
for use with a small biological body to be medically examined wherein the 
mat is equipped with a belt, attached thereto, for securely supporting the 
small biological body; and handle means, attached to the mat portion, for 
facilitating movement along a tabletop.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Features of the present invention will become apparent in the course of the 
following description of exemplary embodiments which are given for 
illustration of the invention and are not intended to be limiting thereof. 
Embodiments of the present invention will now be described with reference 
to the drawings. 
FIG. 1 is a perspective view showing an overall configuration for a 
magnetic resonance imaging (MRI) diagnosis apparatus according to the 
present invention, including a gantry 30 and a mat 1. 
FIG. 2 is a perspective view showing a mat according to the first 
embodiment of the present invention. 
Referring to FIG. 2, the mat for use with the MRI diagnosis apparatus 
includes a mat 1, a belt 3 (four belts in this example shown in FIG. 2) 
attached to a lateral side of the mat 1, and a buckle 2 provided (four 
buckles in this example shown in FIG. 2) at other side of the mat 1 
corresponding to the belt 3. There is provided an opening portion in the 
lateral side of the mat 1, so that part of inside of the mat 1 has a 
hollow portion. 
Referring still to FIG. 2, the mat 1 further includes a tray 7 which can be 
inserted into and pulled out of the hollow portion 9. A surface coil 5 is 
attached to the tray 7. The surface coil 5 applies electromagnetic waves 
to the biological body, and it receives nuclear magnetic resonance (NMR) 
signals from the biological body as well. The tray 7 is also equipped with 
a handle 8 so that an operator thereof can easily operate the tray 7 by 
holding the handle 8. The operator inserts the tray 7 into the opening 
portion 9 and moves the tray 7 in either right or left direction so that 
the surface coil 5 can be placed at a desired position. 
FIG. 3 is a cross sectional view of the opening portion 9 shown in FIG. 2. 
Referring to FIG. 3, an upper layer of the mat presents a two-layer 
construction comprised of cushion material 10 and core material 12 such as 
ABS material, and the surface of the upper layer is covered with cover 
material 11. A lower layer of the mat also has a two-layer construction 
comprised of the core material 12 and a spacer 13, and the surface of the 
lower layer is covered with the cover material 11. The spacer 13, such as 
polyethylene foam, serves to provide a sufficient height for the mat 1. 
Strength of the opening portion 9 is guaranteed by the core material 12. 
Accordingly, in the mat there is provided the opening portion extending 
from the lateral side of the mat, so that the operator can confirm 
accurately the position of the tray to which the surface coil is attached. 
This configuration employed by the first embodiment makes alignment of the 
surface coil to the biological body significantly easy and accurate. 
FIG. 4 is a mat prepared for an infant or small child for use with MRI 
diagnosis apparatus, according to the second embodiment of the present 
invention. 
Referring to FIG. 4, small-child mat 21 has an appropriate size to place 
the small child body thereon. The small-child mat 21 has a belt 3 in a 
lateral side of the mat and a buckle 2 in other side. In a short side of 
the mat 21, there is attached a handle 22 so that the operator can hold 
the handle in order to move the mat easily. 
With reference to FIG. 5, which illustrates the reverse side of the 
small-child mat 21, there is provided a solid plate 23 which is smoothly 
slidable along the tabletop. On top of the solid plate 23, there may be 
provided a mat sponge or the like. Thus, the solid plate 23 can move 
smoothly on the tabletop. 
By employing the small-child mat for use with MRI diagnosis apparatus, the 
small child body to be examined can be firmly supported without pain and 
the small-child mat can be smoothly slided so that the small child body 
can be set to an appropriate imaging position. 
Moreover, different configurations for the small-child mat 21 may be 
provided separately based on the body size of the small-child. Referring 
to FIG. 6A, for example, an infant patient of less than three years old of 
age is placed on the mat having the same width from head to leg portions. 
On the other hand, referring to FIG. 6B, the shape of the mat for use with 
small child of, for example, three year old through seven year old may be 
such that the width for the head portion is narrowed down. Thereby, when 
the infant is photographed, the whole body can be photographed using a 
head coil that is used for photographing adults. 
In summary, according to the first embodiment of the present invention, 
there is provided the opening portion extending from the lateral side of 
the mat for use with MRI diagnosis apparatus, and the surface coil is 
inserted to the opening portion. Thereby, the operator can set easily and 
accurately the position of the surface coil while confirming that with his 
own eyes. Therefore, efficiency for carrying out MR diagnosis is 
significantly improved. 
According to the second embodiment of the present invention, the small 
child patient can be firmly supported without pain to the patient so as to 
be easily moved into the imaging region. Thereby, the MR imaging for the 
small child can be easily carried out. 
Besides those already mentioned above, many modifications and variations of 
the above embodiments may be made without departing from the novel and 
advantageous features of the present invention. Accordingly, all such 
modifications and variations are intended to be included within the scope 
of the appended claims.