Claims:
We claim
1. A probe for a cryosurgical apparatus which comprises: an applicator tip of heat conductive material having thereon a plurality of surfaces of different geometrical contours, each surface being adapted to engage body tissue to be treated; and an insulating sleeve removably positioned over said tip, said sleeve defining an opening positioned to expose only one of said surfaces.
2. The probe of claim 1 wherein said tip has three tissue engaging surfaces.
3. The probe of claim 1 wherein one of said surfaces is substantially cylindrical, one is substantially conical, and one is substantially planar.
4. The probe of claim 3 wherein said opening exposes said substantially cylindrical surface.
5. The probe of claim 3 wherein said opening exposes said substantially conical surface.
6. The probe of claim 3 wherein said opening exposes said substantially planar surface.
Description:
BACKGROUND OF THE INVENTION
The invention pertains to the field of cryosurgery. More particularly, it pertains to cryosurgical apparatus which may be selectively cooled for application to body tissue.
Cryosurgical devices are well known and widely used, both for manipulation and destruction of body tissue. Examples of the former are probes which are caused to adhere to, and assist in the removal of, a cataractous lens from the eye. Examples of the latter are probes which are utilized to necrose diseased tissue of many different types such as, for example, skin cancers and blemishes, cervicitis, and adenoidal and tonsil tissue.
Cryosurgical probes may be refrigerated by any of several means. Originally, they were often cooled by immersing them in, or filling them with, suitable refrigerants, such as liquid nitrogen or dry ice. More recent probes, however, are hollow and are cooled either by a low boiling refrigerant, such as dichlorodifluoromethane (Freon-12) which is allowed to boil within the tip, or by expansion of a gas, such as CO 2 or N 2 O, which cools by means of the Joule-Thomson effect. These refrigerants are usually valved in such a manner that the probe may be selectively cooled or warmed by the surgeon.
Presently known cryosurgical probes are available with applicator tips of many different sizes and shapes, depending upon the type of tissue to be treated, its size, and its position in the body. While the availability of many types of probe tips is a convenience to the surgeon, it also makes it necessary for the surgeon or hospital to purchase and maintain a relatively large inventory. Accordingly, it is a primary object of the present invention to provide a cryosurgical probe having a single, multipurpose tip. Other objects, features, and advantages will become apparent from the following description and appended claims.
SUMMARY OF THE INVENTION
There is provided a probe for a cryosurgical apparatus which includes an applicator tip of heat conductive material having a plurality of surfaces, each adapted to engage body tissue to be treated. A plurality of insulating sleeves are provided which are selectively positionable over the tip. Each of the sleeves defines an opening that is positioned to expose a different one of the surfaces.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a probe tip constructed in accordance with the present invention;
FIG. 2 is a cross section on an enlarged scale taken along the plane 2--2 of FIG. 1;
FIG. 3 is an end view of the tip of FIG. 2;
FIG. 4 is a bottom view of the tip of FIG. 2;
FIG. 5 is a perspective view of the probe tip of the invention and one of the insulating sleeves employed therewith;
FIG. 6 is an illustration of the tip and sleeve shown in FIG. 5 in an assembled condition;
FIG. 7 is a perspective view of the probe tip of the invention with a second insulating sleeve; and
FIG. 8 is a view of the probe tip of the invention with a third insulating sleeve.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With particular reference to FIGS. 1-4 of the drawings, there is illustrated a probe in accordance with the present invention. It comprises a tube 10 which would normally be mounted at one end on a suitable handpiece (not shown). On its other end is mounted a hollow applicator tip 12 of a suitably heat conductive material, such as copper. In the disclosed embodiment, cooling is achieved by the Joule-Thompson effect by means of a high pressure gas expanding from the tip of a delivery tube 14. After expansion and cooling of the gas within the cavity 16 of tip 12, the exhaust gas is returned through tube 10 and vented. It will be understood that the precise method of cooling forms no part of the present invention and such cooling may be affected by other techniques such as, for example, the boiling of a low boiling temperature refrigerant. The tip 12 includes a neck 18 mounted in the end of tube 10 where it is secured by a suitable weld or other means forming a strong gas-tight seal. The particular tip which is illustrated is designed for use in the mouth and has three separate surfaces, each of a different shape and position. An upper cylindrical surface 20 is designed for use on tumors and lesions in the mouth. A lower conical surface 22 is for use on lingual tonsils, nd an inclined planar end surface 24 is for use on palatine tonsils, adenoids, and the posterior walls of the mouth.
In the specifically described applicator tip designed for the purposes set forth, the upper surface 20 is the outer surface of one inch diameter stock turned to 0.995 inch diameter. Its overall length from the end of tube 10 is 0.950 inch. The end surface 24 makes an angle of 50° to the horizontal, as viewed in FIG. 2. The lower surface 22 forms an angle of 20° to the horizontal, also as viewed in FIG. 2. The neck 18 is 0.350 inch in diameter.
Normally, a surgeon will desire to utilize only one of the three surfaces for a specific operative procedure. He will also wish to prevent the other surfaces from adhering to, or otherwise contacting, healthy or untreated tissue. To this end, there are provided three resilient insulating sleeves formed of a material such as polytetrafluorethylene. One such sleeve 26 is illustrated in FIG. 5. It includes a split shank 28 for engaging the end of tube 10, a conical wall 30 conforming to surface 22, and an end wall 32 conforming to surface 24. When positioned on tip 12, as shown in FIG. 6, it exposes only the upper cylindrical surface 20 and protects healthy tissue from engagement with the other surfaces of the tip.
FIG. 7 illustrates a somewhat similar sleeve which exposes only the surface 22, and FIG. 8 discloses a third sleeve which exposes only the surface 24. It has been found that the normal resiliency of the sleeves, coupled with the freezing action of the applicator tip 12, holds them securely in position and negates any requirement for additional fastening means.
It is believed that the many advantages of this invention will now be apparent to those skilled in the art. It will also be apparent that a number of variations and modifications may be made in this invention without departing from its spirit and scope. For example, while a mouth probe has been described, it will be apparent that probes and sleeves for many other multiple uses may be designed. Accordingly, the foregoing description is to be construed as illustrative only, rather than limiting. This invention is limited only by the scope of the following claims.