Description:
BACKGROUND OF THE INVENTION
This invention relates to a skin-testing device for effecting multiple skin tests simultaneously.
Skin testing of persons to determine what materials they may be allergic to has become an essential medical diagnostic tool. It is well known to attempt to apply biologic materials to spaced portions of the skin simultaneously in effecting skin testing of a number of materials. See Laub, U.S. Pat. Nos. 2,235,436 and 2,841,138 and Simon, U.S. Pat. No. 2,522,309. It has also been known to load a liquid biologic on multiple-point scarifiers and to retain the load on the points by surface tension of the liquid cooperating with the capillarity developed by closely adjacent points of the scarifier. See Kravitz, U.S. Pat. No. 3,136,314 and Burelle et al., U.S. Pat. No. 3,291,129.
The instant invention seeks to embody a plurality of multiple-point scarifiers in an improved device for effecting multiple spaced skin tests simultaneously.
When multiple spaced skin tests are applied simultaneously, a relatively large area of the body may be involved. It is difficult to find a large planar body portion or a body portion which readily admits of equal reaction to a testing apparatus which has multiple scarifiers. In Laub, U.S. Pat. No. 2,235,436, the tests are arranged on a flexible strip adapted for adherence to the skin. In Simon, U.S. Pat. No. 2,522,309, scratch type scarifiers are used wherein the interiorly located scarifiers are obscured from view by the horizontally extended handle from which they depend, so that one cannot be sure that all scarifiers will effect scratching simultaneously.
The object of this invention is to provide an improved device for effecting multiple skin tests simultaneously by pressure punctures, and wherein the physician has full view of each scarifier being used and is able to effect substantially identical pressure punctures with each test head of the instrument, even on a nonplanar body portion, thereby insuring uniformity of testing.
A further object of this invention is to provide an improved testing instrument that is characterized by its simplicity and effectiveness in operation and by its inexpensiveness of construction.
Further objects and advantages of this invention will become apparent as the following description proceeds and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming part of this specification.
A preferred embodiment of the invention is shown in the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates my new skin-testing instrument and illustrates its use on the forearm of a patient being tested;
FIG. 2 is a bottom plan view of the instrument of FIG. 1;
FIG. 3 is a side elevational view of the instrument of FIG. 1;
FIG. 4 is an end elevational view of the instrument of FIG. 1;
FIG. 5 illustrates one method of loading liquid antigenic material onto the points of scarifier heads of the instrument; and
FIG. 6 is a fragmentary enlarged cross-sectional view illustrating a modified form of the instrument, particularly in the means for preassembling the biological or antigenic material on the points of the scarifier heads of the instrument.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, one form of the instrument of this invention is illustrated at 10 and its use is shown on the forearm F of a patient, the hand of the physician or nurse applying the test being designated P.
As can best be seen in FIGS. 1--4, the instrument might be termed "centipede shaped" and includes an elongated barlike spine or handle 12 having a plurality of elongated connector means 14 extending, in outrigger fashion, laterally from both sides of the spine 12 in directions transversely to the longitudinal axis of handle or spine 12. At the distal end of each armlike connector means 14 is a multiple-point type pressure puncture head 16.
The multiple-point head 16 is of the type generally disclosed in Kravitz, U.S. Pat. No. 3,136,314 and includes a round base 18, a rectangular or round raised platform 20 centrally of base 18, and nine pressure-type points 22 clustered centrally onto platform 20 so as to create a capillarity effect between the points for holding liquid material in the interstices or spaces between the points 22.
In order that the spine or handle 12 be rigid and easily grasped, it is formed with substantial height, about nine-sixteenth inch relative to thickness, about one-eighth inch. The length of bar 12 is about 4 inches. This shape for handle 12 permits easy grasping by the fingers, as seen in FIG. 1, and avoids blocking of view of the various heads 16. At the same time, the handle 12 provides substantial strength in its plane, which is used to effect transfer of vertically applied forces from handle 12 through arms 14 to all the multiple-pointed heads 16 so as to effect a plurality of multiple-point pressure puncture tests simultaneously on spaced portions of the skin of a nonplanar body part, as shown in FIG. 1. The armlike connector means 14 each joins the lower handle 12 at equally spaced points, about thirteen-sixteenth inch on centers, adjacent the lower edge 12a. The arms 14 are rod-like with a transverse dimension of about one-sixteenth inch-- three thirty-seconds inch. Each arm has a horizontal portion 14a, an elbow 14b intermediate the ends of arm 14, and a downturned and slightly outwardly inclined upright section 14c.
While the base 18 of pressure puncture head 16 is round, the distal end of arm 14 connects to head 16 adjacent an edge of head 16 closest to spine 12. A triangular brace web 14d, lying in the plane of arm 14, is provided diametrically of the back side of base 18 and between base 18 and arm portion 14c, so as to rigidify the attachment of the multiple-pointed head 16 to the distal end of arm 14 without substantially increasing the amount of material used or obstructing the view of each head 16 and its points 22.
Each elongated arm 14 is so small in cross section as to provide relative flexibility both at the juncture of arm portion 14a with relatively rigid spine 12, and also at the elbow 14b. Thus, there may be some bending of arm 14 at its connection with handle 12 in a plurality of directions, such as both in the plane of arm 14 and transversely to said plane.
The entire instrument is integrally molded from a plastic material making the same inexpensive but effective for its intended purpose. After a single use, the instrument may be discarded, thus avoiding any infection, such as transmission of infection hepatitis to a later user.
In the loading of antigens, allergens, or other biologic substances onto the points 22 prior to application as in FIG. 1, two systems are suggested. The first system shown in FIG. 5 utilizes a rectangular biologic-carrying base 30 constructed to have 12 wells 32 defined therein for cooperation with the 12 multi-pointed heads 16 of the centipedelike instrument of FIGS. 1--4. The diameter of each well 32 is of a size to admit the circular base 18 of head 16. Each well carries liquid, or semiliquid or semidried material therein positioned to have the points 22 of the head 16 immersed therein. If desired, each head 16 may be provided with an annular flange 16a, of greater diameter than base 18 and located at the upper end of base 18, for engagement with portions of base 30 to limit entry of heads 16 into wells 32.
Each well 32 may be filled to a desired depth with a different biological material, such as an allergen, with different specific materials being assigned to different wells in a predetermined pattern or arrangement known to the person applying the material and later reading the results of the test.
The second system of loading the biologic substances on the points 22 of a head 16 is illustrated in FIG. 6 and utilizes the principles disclosed in Burelle et al., U.S. Pat. No. 3,291,129. As shown, each head 16 is provided therein with an annular groove 40 surrounding platform 20. A tube 42 sealed at its distal end 42a and carrying liquid biologic material 44 therein is provided with the other end of tube 42 fitted over platform 20 and entering groove 40. The arrangement holds the liquid material 44 in position against platform 20 with points 22 immersed therein, and without leakage, so that when a tube 42 is pulled off, the points 22 are exposed carrying biologic 44 thereon in the interstices or spaces between points 22.
The entire arrangement of FIG. 5, including base 30 and instrument 10 assembled, or the separated portions thereof, may be provided packaged in sterile condition in a box or other suitable container (not shown). After removing the instrument from its package and uncovering the wells 32, the wells may be filled to desired levels and the heads 16 are to be dipped as shown in FIG. 5, after which the multiple tests are applied as in FIG. 1. Alternatively, in the system of FIG. 6, the instrument 10 is supplied with each head 16 carrying preassembled thereon the biologic material 44 in tube 42. The tube 42 for each head 16 may then be removed, and the points 22 remain loaded with biologic 44, after which the instrument is used as in FIG. 1.
It will be understood that in applying the instrument as in FIG. 1, the physician or nurse is able to easily see which heads 16 have had their points 22 forced into the skin in a manner so as to properly elicit a test reaction. Where the body portion is not planar, only a slight rocking motion of the handle 12 is necessary to bring each head 16 into proper operative skin-puncturing association with the selected skin area. During such rocking motion, the multiple contacts of a plurality of other heads 16 with the body prevents any slippage of the instrument and thus avoids undesired scratching with points 22.
While there has been shown and described a particular embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention and, therefore, it is intended in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.