US 2829636 A
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Description (OCR text may contain errors)
April 8, 1958 u. K. HENscl-IKE APPARATUS FOR THE RADIoAcTTvE TREATMENT oF ANIMALS Filed July 15, 195? 2 sheets-sheet 1 1N VENTOR. C/. /E/CH fhfA/SCHKE.
U. K. HENSCHKE y April s, 195s APPARATUS FOR THE RADIOACTIVE TREATMENT OF ANIMALS y 2 Sheets-Sheet 2 Filed July 15, 1957 Felcr/oA/AL CoA/raar United States Patent O APPARATUS FOR THE RADIOACTIVE TREATMENT F ANIlVIALS Ulrich K. Henschke, Forest Hills, N. Y. Application July 15, 1957, Serial No. 671,959 Claims. (Cl. 12S-1.2)
This invention relates to the treatment by radioactive means of affected portions of the legs of animals. More particularly, it relates to apparatus for application to the animals leg toeifect the Asaid treatment.
Many animals and particularly race-horses are prone to joint and tendon `diseases which account for considerable economic losses to -their owners. Until this time methods of treating such diseases, among the more common of which are bursitis, tenosynovitis, bowed tendon, buck shin and joint inflammation, none ofwhich are malignant conditions, have largely consisted of` ring, blistering or painting which` have not proved very effective.
vRecent experience with X-ray therapy such as used in the .treatment of similar diseases in human beings has proved effective, but such treatment is attended by many difficulties. Obviously, X-ray therapy centers for man cannot be used for lanimals and consequently expensive X-ray machinery and buildings must be provided largely for the treatment of this group of diseases. A fewsuch X-ray centers do exist for the exclusive treatment of animals, particularly race-horses, but transportation of the animals for treatment is expensive, and particularly with horses lit is extremely diicult to restrain the animal in position during` treatment.
It is an object of the present invention to overcome the aforementioned diculties 'attendant X-ray therapy by providing a portable device for application to :the affected portion of the animals leg. It is a further object to provide apparatus for application to the animals leg by means of which a plurality` of sources of radioactive material may be placed in` close proximity to the affected or diseased area of the leg. It is a still further object of the present invention to provide apparatus for the radioactive treatment of the legs of animals which does not require restraint of the animal during thetreatment.
It is well known to use radium for the treatment of such diseases in animals, but due tothe lack of a suitable carrier, a satisfactory dose distribution has heretofore not been possible and damage to the skin and hair has often resulted. For example, up to this time if one wished to apply a dose of radioactivity to a portion of a bone centrally located within a fleshy part of the animals leg one would apply a source of material such astradium on one side of the leg directedat the bone. After a sufficient dose, that is, one calculated not to damage the skin, the sourcewould be moved to another area of the leg and again directed at the bone and so on. In this manner the skin adjacent the source of radioactivity would presumably not receive an overdose of radiation. However, the larger the area to be treated the more time-consuming the process becomes, and accordingly two sources of radiation on opposite sides of the affected area mightbe thought to accomplish thetreatment in a shorter time. However, damage to the skin and tissues adjacent the sources of radioactivity is not uncommon.
`In accordance with the present invention apparatus 2,829,636 Patented Apr. 8, 1958 ice is provided which includes a flexible band or carrier adapted to surround the area of the animals leg to be treated. A plurality of receiving means, preferably integral with the exible band, are arranged at substantially uniformly spaced intervals thereon. A lesser number of tubular retaining elements with open upper ends are removably positioned within certain of the receiving means and held therein against the normal movements of the animal preferably by a friction fit. The retaining elements are spaced substantially uniformly on the flexible band over its effective length, or over the periphery of the band when it is in position on the animals leg. An elongated capsule containing radioactive material is provided for insertion into each of the retaining `elements when the flexible band is in position on the leg, with each capsule and retaining element adapted to provide mutual frictional contact, thereby facilitating retention of the capsule against the normal movement of the animal. In addition to the flexible band and elements just described, the present invention contemplates spacer i means intermediate the animals leg and the flexible band;
The spacer is preferably not an integral part of the band for reasons set forth hereinafter, but is desirably a separate band of at least about one-half inch thickness which is applied to the areaof the leg to be treated and the flexible band is then secured thereabout.
In the drawings:
Fig. l is an elevation of a preferred form of iiexible band illustrating integral retaining means with retaining elements and capsules in position thereon;
Fig. 2 is a top view of the apparatus of Fig. l, but without the capsules in position, also illustrating a preferred spacer means construction;
Fig. 3 is a partial vertical section through the leg of an animal with the apparatus of the present invention, exclusive of capsules, in position thereon; p
Fig. 4 is a perspective of the hind quarters of a horse showing the apparatus of the present invention in posi tion for treatment;
Fig. 5 is a vertical section through one of the retaining elements illustrating the radioactive capsule in position therein and a preferred construction of capsule and retaining element for assuring fiictional contact there,- between;
Fig. 6 is a vertical section through a retaining element and capsule illustrating the loading of radioactive material therein and another construction for assuring retention of the capsule in position;
Fig. 7 is a perspective view of the ends of the retaining element and capsule further illustrating the snapt construction of Fig. 6; and
Fig. 8 is a perspective illustrating another modification of the apparatusof the present invention.
Referring first to the apparatus of Figs. 1-7 and speciiically to Fig. 1, the band portion 11 is of a flexible material, such as heavy canvas, which if desired may also have elastic properties. As seen in Fig. 2 the band 11 is provided with a plurality of receiving means 12 on `its outer periphery wihch are uniformly spaced one from the other and preferably one adjacent the other. When the band is canvas or a similar material, the receiving means are made an integral part thereof by folding the band upon itself as at 13 in Fig. 1, and stitching transversely of the band as at 14 and just above the fold as at 15 so that the receiving means 12 are actually pockets in the outer surface of the band. Tie strips 16, 17 are stitched to the flexible band adjacent its ends to enable the band to be drawn up on the leg and secured in position as by the knots 18 in Fig. 4.
As shown in Figs. 1-3 tubular retaining elements 19, open attheir upper ends, are inserted into certain of the receiving means or pockets 12 of the band at uniformly spaced intervals. The spacing between adjacent retaining elements will be dictated bythe diameter of the portion ofthe animals leg being treated, with care being taken that when the exible band is in position on the leg, the receiving elements are spaced substantially equidistant from one another about the exterior of the band. Generally from four to eight retaining elements are employed with six being preferred. They are desirably of metal or rugged plastic in order to withstand the rough treatment to which they may be subjected by the animal undergoing treatment, with brass or stainless steel being preferred.
The receiving means or pockets 12 in the band are of suflicient cross-sectional dimension to just accommodate the tubular retaining elements in order to assure a reasonably tight friction iit and retention of the retaining elements againstmovements of the animal with the band positioned about its leg. For example, with retaining elements of approximately 3/1f;" O. D. stitch lines 14 approximately f/GJ/" apart provide pockets from which theelements are not easily removed. When the receiving means are metal loops for example aiiixed to the periphery of the band, auxiliary means are preferably provided to assure retention of the retaining elements therein. In any event it is toI be understood that the manner of attachment of the retaining elements to the receiving means on the band may be varied except insofar as the aforementioned spaced relationship between retaining elements is adhered to and the attachment of the elements to the band is secure.
. Referringnow to Figs. -7 the radioactive material is contained in `an elongated capsule 21 of diameter just slightly less than the inside diameter of retaining elements 19.' vThe capsule is provided with closure means, preferably a threaded plug 22 at its upper end. Capsule 21 is slightly longer than the effective inside length of the retaining element in order to permit grasping of the same by the tool used to insert and withdraw the capsule. If the radioactive material is linely divided as radium powder or cesium 137, this material is contained in a plurality ofsmaller capsules 23 preferably of stainless steel. These smaller capsules are arranged in the elongated capsule 21 in the manner illustrated in Figs. 5 and 6 with spacer elements 24 therebetween. The small capsules of radioactive material are thus positioned so that near the ends of the elongated capsule 21 they are closer together than they are in the center of the capsule. This is termed heavy end loading and assures uniform radiation at a given distance from capsule-21 over its entire length. Cobalt 60 t on the other hand is not encapsulated since it is available in solid alloy form, and small pieces of the alloy corresponding to capsules 21l are loaded between spacers 24 in the large capsule 21, as are radium capsules for example.
Since as will be shown hereinafter the radiation dose obtainable from capsule 21 is substantially higher than the permissible daily exposure should the capsules be touched by the operators hand, it is important that when the capsules have been placed in the retaining elements secured to the animals leg that they remain therein against the normal movements of the animal. That is to say they must be secure against longitudinal movement in the retaining elements. It has been found that a close friction t between the exterior of the capsule and the interior of the retaining element is sufficient to assure retention. This is preferably attained by bending slightly either the capsule or the retaining element, and preferably the latter, so that at least over a portion of their length the axes of the respective parts are olset from one another, or in other words the axis of the retaining element for example is generally arcuate, whereas the cap-- sule axis is straight. This slight bending permits close frictional contact between the walls of the respective parts over a considerable distance at ,at` least one. point, and,
4 generally at least at the three points illustrated in Fig. 5. A suitable friction t may be attained in a variety of other obvious ways, as pinching the retaining element at several points to restrict its inner dimension, for example, or raised portions might be provided on the exterior of the capsule.
Alternatively, simple locking means may be provided for securing the capsule in position in the retaining element, as for example the snap arrangement illustrated in Figs. 6 and 7. The retaining element is desirably stamped as at 26 to provide a series of dimples, usually 4 to 6 in number which protrude into the tube. The capsule 21 is provided with an annular protuberance 27, which in cooperation with dimples 26 provides a snap for retaining the capsule in position. Whether a snap or similar arrangement or simply a friction fit as illustrated in Fig. 5 is provided for securing the capsule in the retaining element, the capsule must be easily releasable from the retainer by the operator in response to a quick upward movement, as with a pair of forceps grasping the protruding end of the capsule. A modified form of the apparatus of the present invention is illustrated in Fig. 8. In this modification the flexible carrier band is in two pieces 41 and 42, which when in position on the leg overlie spacer means 43 which is considerably wider than the bands. Each of the bands is provided with a series of receiving means or pockets 12 on its periphery. Retaining elements 19 are of similar construction to those already described, but are provided with auxiliary clips 44 which engage the exterior of receiving means 12 and facilitate retention of the elements in position on the band.
As mentioned earlier spacer means are employed in conjunction with the present `apparatus for the purpose of removing the sources of radioactivity suciently far from the skin of the animal to prevent damage thereto. The spacer is preferably of felt or foam rubber, preferably of a thickness of at least one-half inch. Other materials may of course be employed, in fact the spacer may be of metal, but in any event it should be of a material having a suiciently high coefficient of friction to prevent sliding when in position on the leg and to provide a fairly rough outer surface over which the exible band is applied. In Fig. 2 a spacer 28 is shown adjacent the under side of the flexible band 11. Since the flexible band is desirably of su'icient length to completely enclose any portion of the animals leg the spacer means is preferably not secured to the band in order to avoid spacer overlap when treating the smaller portions `of the leg. While one flexible band may serve to treat any portion of the leg regardless of its size, a plurality of spacers of varied length are preferably provided. The ends of the spacer may be tapered as at 29 to provide uniform thickness where the ends join as at 31 in Fig. 3. The ends may of course be squared if desired. The spacer may of course consist of a plurality of pieces of felt or foam rubber.
As the rst step inr applying the present apparatus to the animal, the spacer is placed about the area of the leg to be treated, after which the exible band is wrapped thereabout and tied in position. Several retaining elements, usually six in number, are then inserted into the receiving means or pockets on the periphery of the band at equally spaced intervals to assure uniform dosage to the bone or ycentral portion of the leg from the several radioactive sources which are subsequently inserted in the receiving means. A shielded lead container in which the capsules containing radioactive material are disposed is then opened and each capsule is individually lifted with a long handled forceps and inserted one after the other into lthe retaining elements. The capsules are pushed downwardly therein to assure the aforementioned friction t or engagement of the snap or other locking means to secure them against the movements of the j animal. The apparatus now containing the capsules of radioactive material is allowed to remain in position on the horses leg for a period of 24 hours. When treatment has -been completed, the reverse process is employed, with the capsules rst being removed by means of the long handled forceps and returned to the `lead container. In most instances for thev diseases abovementioned, from three to six treatments are required, spaced from one day to one week apart, depending upon the seriousness of the condition.
While radium, cesium 137 and cobalt 60 have been mentioned as the radioactive materials employed, cobalt 60 is preferred, not only because of its high rate of emission of gamma rays, but also because it is available in massive solid alloy form, for example, cobanic which contains about 50% cobalt 60. This `material is considerably safer than radium or cesium 137 since the latter materials must be encapsulated, and thereis always a chance of rupturing the small individual capsules with escape of the nely divided radioactive powder.
To effect the aforementioned treatment, the total quantity of radioactive material contained in the capsules employed in the present apparatus is about 50 mg. of radium or 30 millicuries of cobalt 60 or 140 mc. of cesium 137. Since six capsules are generally employed, each capsule will contain 1/6 of the radioactive material. For example, each capsule will contain 5 mc. of cobalt 60, preferably in ten pieces of 1/2 mc. each, and the capsule is heavy end loaded with metal spacers intermediate the pieces of cobalt 60. Radium is employed in the form of radium sulphate and cesium 137 in nely divided form. The smaller capsules containing these latter materials are approximately 1 cm. long preferably of stainless steel construction and have a wall thickness of about l mm. The small capsules are welded closed as a safety precaution.
While cobalt 60 is preferred because of its high activity and massive solid state, a considerably larger and of course heavier lead container is required for housing the capsules than with cesium 137. Cobalt 60 and radium have approximately the same half value layer, namely about 12 mm. of lead, whereas the half value layer of cesium 137 is only approximately 6 mm. of lead. Thus when the capsules contain radium or cobalt 60 the safe or container for housing them weighs approximately 100 pounds, whereas with cesium 137 the container `need only weigh about 30 pounds. The lead container presently being employed for cobalt 60 capsules is approximately 7" in diameter and about 8 high with a well therein of depth slightly greater than 6". The lead cover is approximately 2 thick. As constructed the container provides a minimum of 2" of lead surrounding the capsules which are vertically disposed in the well.
The capsules should be handled only at arms length with a pair of long forceps. When the forceps or other handling tool is at least 2O centimeters long, there is virtually no chance for the operator to receive an overdose of radioactivity. For example, each of the capsules contains 5 mc. of cobalt 60 or its equivalent in radium or cesium 137. This quantity of cobalt 60 delivers 67,500 milliroentgens per hour at a distance of l centimeter. When the capsules are handled with 20 centimeter forceps, radiation at the handle of the forceps is about 170 mr. per hour or about 3 mr. per minute. When inserting or removing the capsules from the container to or from the retainer elements on the flexible band in position on the animals leg, the lead container housing the capsules is placed about l0 feet from the animal which is cross-tied or otherwise restrained. Approximately l0 seconds is required to remove one of the capsules with forceps from the lead container, transfer the same to the retainer element and insert it. With six capsules approximately l minute is required to place all of the capsules in position on the animal and thus the maximum exposure to the hands of the operator is 3 mr. Since the permissible daily exposure to the hands is now agreed to be 250 mr., the operator may effect a great many treatments each day without danger of receiving an overdose of radioactivity. With respect to exposure of the operators body, there is also little chance of exceeding the permissible daily exposure of 50 mr. since no portion of the body will at any time be closer than 50` centimeters from the radioactive capsules, and at this distance the dosage is 30 mr. per hour, or 1/2 mr. during one application requiring approximately l minute.
The importance of the aforementioned precautionary measures in handling the capsules of radioactive material cannot be overemphaszed for if one of the capsules is touched directly, with a period oi. contact of even less than a second, more than the permissible daily does would be delivered to the hands. However, if the outlined procedures are followed the apparatus of the present invention may be used correctly and safely by a person who may be largely inexperienced in radiation therapy.
The present apparatus is intended for use only in the treatment of non-malignant conditions or diseases of the legs of animals, and particularly diseases of horses, some representative conditions of which animal are mentioned above. The apparatus of the present invention is not intended for the radio therapy of humans.
This application is a continuation-in-part of my copending application Serial No. 490,258, tiled February 24, 1955, and now abandoned.
What is claimed is:
l. Apparatus for radioactively treating the bones and tissue of an animals leg which comprises a spacer means, a band adapted to surround such spacer means over the area of the leg to be treated, receiving means integral with and arranged transversely on said band, tubular retaining elements with open upper ends, cach secured Within said receiving means and substantially uniformly spaced on said band when the same is in position on the animals leg, and an elongated capsule containing radioactive material inserted into each of said retaining elements when the band is in position on the leg.
2. Apparatus for radoactively treating the bones and tissue of an animals leg which comprises a spacer means, a band adapted to surround such spacer means over the area of the leg to be treated, receiving means integral with and arranged transversely on said band, tubular retaining elements with open upper ends, each secured within said receiving means and substantially uniformly spaced on said band when the same is in position on the animals leg, and an elongated capsule containingradioactive material inserted into each of said retaining elements when the band is in position on the leg, said capsule and retaining element being adapted to provide frictional contact therebetween thereby facilitating retention of the capsule within the retaining element against the normal movements of the animal.
3. Apparatus for radioactively treating the bones and tissue of an animals leg which comprises a spacer means, a flexible band adapted to surround such spacer means over the area of the leg to be treated, said exible band having on its periphery a plurality of transversely arranged, substantially uniformly spaced pockets, a lesser number of tubular retaining elements with open upper ends, each within said pockets retained therein against the normal movements of the animal, and so arranged as to be substantially uniformly spaced on the exible band when the same is in position on the leg, and an elongated, closed end capsule member containing radioactive material inserted into each of said retaining elements when the flexible band is in position on the leg.
4. Apparatus for radioactively treating the bones and tissue of an animals leg which comprises a spacer means, a band adapted to surround such spacer means over the area of the leg to be treated, receiving means integral with and arranged transversely on said band, tubular retaining elements with open upper ends, each secured within receiving means `and substantially uniformly spaced on said band when the same is in position on the leg,
,and an elongated, closed end capsule containing radiosaid capsules being non-uniformly loaded, with the sources of radioactivity being more closely spaced toward the ends of the capsule than adjacent its center, thereby providing a substantially uniform dose over the treated area.
5. Apparatus for radioactively treating the bones and tissue of an animals leg which comprises a spacer means, a ilexible band `adapted to surround such spacer means in contact with the area of the leg to be treated, said flexible band having on its periphery a plurality of transversely arranged, substantially uniformly spaced pockets, a plurality of tubular retaining elements with open upper ends, each of said elements within and in close frictional contact with certain of said pockets and so arrangedA as to be substantially uniformly spaced one from the other on the flexible band when the same is in position on the leg, and an elongated, closed-end capsule member containing radioactive material inserted into each of said retaining elements, said capsule member being at least partially retained within said element against normal movements of the animal through frictional contact with the inner wall of said element.
FOREIGN PATENTS Germany Oct. 21, 1935 Bell Sept. 4, 1917