Appliance For Interstitial Radiation Of Organs In The Body

Abstract

An appliance for the interstitial radiation of organs in the body of man or animals comprises a cannular tube which contains a radioactive compound and which is attached to the end of a rod provided with a handle. A sheath can be adjustably displaced along the cannular tube and rod and is arranged to tightly surround the tube and rod. The sheath is radiation-absorbing at least at the outer part, which can be brought to cover, more or less, the radioactive compound in the cannular tube.

Description

The invention relates to an improvement in appliances with cannular tubes for interstitial radiation of organs in the body of man and animals. Such an instrument, which has come into use particularly with radiation of the pituitary gland with Sr.sup.90, is described in Fortschritte auf dem Gebiete der Rontgenstrahlen und der Nuklearmedizin, Bd 106 (1967) pp. 574- 578. It consists of a shaft 2 mm wide and approximately 25 cm long provided with a handle 2 cm long and, attached at the end of the shaft, a cannular tube 1 mm wide and 30 mm long of stainless steel having a material thickness of 0.14 mm, which is plugged at the outer end with a steel plug 1 mm long and has a 4.5 mm length of strontium sulphate containing Sr.sup. 90 packed between the steel plug and a 3 mm long plug of indium which fits tightly against the tube wall. This instrument offers considerable advantages for radiological therapy over conventional methods with inserts of Y.sup.90 or Au.sup.198 , for example.

The object of the invention is to improve the known type of appliance by making the radiation adjustable.

The appliance according to the invention comprises a cannular tube containing a radioactive compound and being attached at the end of a rod provided with a handle and is characterized by a sheath which can be adjustably displaced along the cannular tube and rod and suitably tightly surrounds these, said sheath being radiation-absorbing at least at the outer part corresponding to the length of the compound in the cannular tube. The sheath is suitably joined to the rod or the handle by means of threading. On the handle there should be a grading or scale on which can be read with an index how much of the compound in the cannular tube projects outside the sheath. Between the indium plug and the rod the cannular tube is suitably filled with a spacer rod of, for example, stainless steel, so that the cannular tube is strengthened.

One embodiment of the appliance is shown in the accompanying drawings where

FIG. 1 shows the appliance in its entirety,

FIG. 2 is an enlarged illustration of the point of the appliance and

FIG. 3 is an enlarged illustration of the handle and adjacent portion of the sheath.

The cannular tube 3 is attached to the end of the rod 2, only indicated in the drawing, provided with a handle 1. The tube has an outer plug 4 and an inner plug 5 which enclose a compound filling 6. The inner part of the cannular tube is filled by a spacer rod 7. A sheath 10 acting as diaphragm, which should have a material thickness of approximately 0.5 mm at least in the part which is to entirely or partly cover the compound 6, surrounds the rod 2 and the cannular tube 3 and is attached to the handle 1 by way of a cylindrical body by means of threading (not shown) so that it can be displaced and expose a greater or smaller quantity of the compound filling 6. The position of the sheath can be read on the scale 12 on the cylindrical body 11 with the help of the end surface 13 of the handle which serves as an index.

With the appliance according to the invention the following advantages are gained, inter alia: It is possible with one and the same appliance to obtain a radiation effect along an adjustable length of the active part of the appliance, for which otherwise several radiation sources with different lengths must be used. The adaptability of the active part facilitates adjustment of the point of the appliance after it has been inserted into the organ to be irradiated. When the part of the body is shown on a fluorescent screen it may be found that an error of judgement has been made in determining the size of the part to be irradiated. Furthermore, handling of the applicance is much safer since the diaphragm may be permitted to cover the entire radiation source while the appliance is being handled and even during insertion into the body. In this way the ineffective exposure to radiation is reduced for the operation staff and the patient. The construction also provides appreciable reinforcement against breaking. The point of the appliance, that is the cannular tube, is in itself fragile.

Claims

What is claimed is:

1. Appliance for interstitial radiation of organs in the body of man and animals, comprising an elongated hollow rod, a radioactive compound disposed within one end of said rod, a handle fitted on the opposite end of said rod, said handle having a screw-thread formed thereon, an elongated tubular sheath being in closely fitting relationship with and enclosing at least a portion of said rod and being axially displaceable thereon, said sheath being shorter than said rod, the end of said sheath adjacent the end of said rod containing said radioactive compound including a radiation-absorbing material extending for at least the length of the radioactive compound in said rod, the opposite end of said sheath being arranged in threaded engagement with the screw-thread on said handle for axially displacing said sheath relative to said rod for selectively uncovering any desired length of said rod containing the radioactive compound, and scale and index means cooperatively arranged on said handle and said sheath for indicating the axial length of said rod containing the radioactive compound which projects outwardly from the radiation-absorbing end of said sheath.

2. Appliance, as set forth in claim 1 characterized in that an outer plug being fitted into the end of said rod containing the radioactive compound, an inner plug positioned within said rod at the opposite end of the radioactive compound from said outer plug, and a spacer rod extending axially from said inner plug toward the opposite end of said rod on which said handle is fitted.