Untitled record

(42) Date of commencement of the patent: 15. 1.1990 (45) Date of issue: 10. 7.1990

<td>(56) Documents:</td><td>(73) Patent owner:</td>

<td>US PS4105030</td><td>AUSTRIAN RESEARCH CENTER SEIBERSDORF GESELLSCHAFT MBH A-1010 VIENNA (AT). (72) Inventor: HAWLICZEK ROBERT DR. VIENNA (AT). NEW BUILDER JOSEF ING. VIENNA (AT).</td>

(54) APPARATUS FOR INTRODUCING RADIATION SOURCES (57) The invention relates to an arrangement for dispensing in particular cylindrical radiation sources (9) from a container or for introducing the radiation sources (9) into a predetermined target volume (11) with a hollow needle (1). According to the invention, provision is made for a clamping device (19) for the mandrel (8), with which the latter is held in a fixed position with respect to the target volume (11) and that the hollow needle (1) is held in place with a fixedly clamped mandrel (8). is guided in the direction of this displaceable.

CQ

AT 390 884

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No. 390,884

The invention relates to an arrangement for introducing cylindrical radiation sources, preferably for irradiation in the low-dose region in a specific mutual position or sequence in a predetermined target volume with a pre-filled with the radiation sources hollow needle, which includes a mandrel for expelling the radiation sources and on this is slidably guided.

For the treatment of malignant tumors radioactive radiation sources are used in medicine. For this purpose, enclosed or abrasion-resistant radioactive substances are introduced into the tissue, where they also remain there in the sequence. The number, position and activity of the radiation sources is calculated so that the desired total radiation dose is achieved in the tissue in question, taking into account the steadily weakening dose rate, due to decreasing activity. The introduction of the radiation sources, which are in cylinders or cylinder-like form (so-called seeds), takes place with the help of a hollow needle. Of great importance for the success of the treatment is the exact location of the seeds in the target volume. A tumor located or surgically exposed by diagnostic procedures is populated with a calculated number of seeds. With the previous introduction method, there is the problem of insufficiently accurate placement of the seeds. They should be spread over the target volume at predetermined intervals parallel to each other or to lie in the axis. According to previous methods are as a result of active ejection of the seeds from the hollow needle many seeds obliquely to the needle axis or in a transverse position or are not stored, as they stick to the sliding back hollow needle. Although these circumstances can be subsequently determined by means of X-ray images, but no longer be corrected. The consequence is an inaccurate metering distribution in the target volume, which may result in a limitation of the treatment success.

An arrangement of the type mentioned is known for example from US-PS 4,105,030. However, the introduction of pellets can not be done with this device with the often required accuracy.

The aim of the invention is to improve the accuracy of the introduction of radiation sources. Radiation protection for the relevant personnel should also be improved. This is achieved according to the invention in a device of the aforementioned type, that a clamping device is provided for the dome, with which it can be kept in a fixed position with respect to the target volume, wherein the clamping device is mounted on a possibly provided with a scale carrier adjustable and lockable, which support on a positionally adjustable with respect to the target volume adjusting device, is preferably pivotally mounted on all sides, in order to be able to introduce the radiation sources into the target volume after insertion of the hollow needle and successful adjustment of the position of the mandrel by displacement of the hollow needle in the direction of the dome.

A preferred embodiment is characterized in that the radiation sources are arranged in a container having a tubular memory for in a predetermined position in these insertable radiation sources and can be coupled at one end to the hollow needle, the dome from the other end of the container forth in the memory is insertable. It is also expedient if in the memory between the radiation sources fixed, non-radiating spacers are arranged, which are absorbable by the tissue.

The seeds can be inserted separately through the special spacer (spacers) with the help of the dome from the previously filled memory in the hollow needle. Thereafter, the mandrel relative to the adjusting device with the carrier and the clamping device is fixed in position and finally the hollow needle is withdrawn over the mandrel, so that seeds and spacers remain in the same position as in the hollow needle in the target volume in the predetermined position.

Usually, a plurality of hollow needles are introduced into the target volume and withdrawn in succession over the respectively newly introduced dome.

By using a glass tube as a memory for receiving the seeds and spacers, there is the possibility of control over the desired arrangement of spacers and seeds, since the container can be formed with a viewing slit without the risk of losing radiation sources.

It is also advantageous if on both sides of the memory in the passage of the radiation sources or spacers projecting closure devices, for. B. resilient tongues, are provided which allow the passage of the dome or the radiation sources and spacers under pressure load.

Preferred embodiments of the invention will become apparent from the following description, the drawings and the dependent claims.

In the following the invention will be explained in more detail with reference to an embodiment shown in the drawing.

The Fig. shows schematically the structure of the inventive arrangement comprising a hollow needle (1), a tubular memory (3) and a dome (8) which is insertable into the memory (3). The hollow needle (1) is a two walls (4), (5) existing container via a Luer-lock coupling (2) connected so that the memory (3) and the hollow needle (1) are aligned. With the help of the via a terminal (7) of the container with receiving cone (26) in the memory (3) insertable dome (8) radioactive seeds (9) and spacers (10) in the hollow needle (1) to a through the location of the target volume (11) inserted predetermined depth. Then the dome (8) in a jig (19), which provides a number of clamping options, fixed with a locking screw (21). The clamping device (19) is displaceable and lockable by means of a locking screw (20) on a support (16) which is connected to a scale (18) to adjust the dome (8) relative to the hollow needle (1) or to be able to fix. The carrier (16) is by means of a

-2Nr. 390 884

Ball joint part (17) rotatably mounted in a bearing (14) and fixable with an adjusting screw (15). The bearing (14) is mounted on an adjusting device (22), which is fixed in position relative to the target volume (11). In the present case, the adjusting device (22) is a bracket, which is arranged by means of spacers (12), for example, around the head (13) of a person positionally fixed to this. In the adjusting device (22) a number of holes as guides (23) is provided, the z. B. in bearings (24) are pivotally mounted to lead hollow needles (1) in different directions in predetermined target volumes can. (At the same time several needles can be introduced into the target volume (11) through different holes (23)). The bearings (24) are lockable, and the hollow needle (1) fixed in them to obtain a well-defined arrangement of target volume, hollow needles with seeds and spacem and Dom. After reaching this arrangement, the hollow needle (1) is withdrawn over the fixed mandrel (8) and the seeds and the spacers remain in the planned position. Present description refers to neurosurgical implantation; other applications are also possible.

The loading process of the memory of a glass tube (3) with seeds (9) and spacers (10) by two nested, each with a longitudinal slot (6) provided, the container forming steel tube (4), (5), which are rotated against each other can, for. B. by one with the terminal (7) and one with the coupling (2) is connected, are observed (see cross-sectional view). In this way, view exists like a window that can be opened or closed. When closed, the residual radiation on the outside of the container (4), (5) is negligibly small.

At both ends of the memory (3) or container (4), (5) are facilities, for. As tongues (25), (26), which prevent falling out of the seeds (9) and spacers (10), but allow the pushing out in the desired direction easily.

To load the memory (3) serve their own loading devices.

The arrangement according to the invention is used in particular for irradiation in the low-dose-rate range, in which in the human body in this remaining seeds (9) are used, while the spacers (10) are formed by a material dissolving in the body.