Description:
BACKGROUND OF THE INVENTION
This invention relates generally to medical diagnostic instruments, and has particular reference to a novel otoscope construction with improved means for using the instrument as a closed head or pneumatic type otoscope.
In an ear examination, it is often desirable to introduce air into the ear canal in order to observe the action of the tympanic membrane under pressure. This is done through an otoscope and requires an instrument with a closed head so that there is no air loss. Since it is also necessary to have open head otoscopes, i.e. with an open passage therethrough, for instrumentation or the like, some otoscopes of the prior art have been provided with heads of both types. This makes a complete instrument relatively expensive and has the disadvantage of necessitating frequent changing from one head to the other.
A more common type otoscope in use heretofore is one in which the head is provided, at the proximal end of the viewing passage, with a pivotally or hingedly connected closure which can be moved into passage closing position for use as a closed head instrument and swung completely clear of the passage for use as an open head instrument. A problem with this type of otoscope is that it is difficult to get a good seal between the closure and head when the former is moved into closed position. Another disadvantage is that instruments of this construction, insofar as applicants are aware, are invariably shaped and dimensioned so that only monocular vision is possible and there is usually insufficient space for both good viewing and instrumentation.
SUMMARY OF THE INVENTION
The invention to be disclosed herein is an otoscope that is readily convertible from an open to a closed head type, and vice versa, the closed head condition being effected by a slide closure having a novel construction that insures an airtight seal. Unlike conventional instruments, the otoscope head has a generally rectangular shape with a large proximal or rear end opening that permits binocular vision as well as more space for both viewing and instrumentation. The slide closure, which can be completely detached from the instrument head, comprises a lens and a lens frame formed of an elastomer whereby the elastomer frame operates as an airtight gasket between the lens and otoscope head when the closure is in position in the latter. The elastomer lens frame, in addition to providing a truly effective seal, protects the lens against breakage if the closure is dropped. Making the closure completely detachable from the otoscope head is advantageous because it permits use of a number of interchangeable closures with different lenses. Another advantage of the otoscope of the invention, as will appear more fully hereinafter, is that the head and speculum portions are molded as a one-piece or unitary construction which results in economies in production .
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an otoscope embodying the invention and the upper part of a supporting battery handle;
FIG. 2 is a perspective view of a pneumatic attachment for the otoscope;
FIG. 3 is an enlarged side elevation of the otoscope with the slide closure in position therein;
FIG. 4 is a top plan view of the otoscope of FIG. 3;
FIGS. 5 and 6 are front and rear elevations, respectively, of the otoscope of FIG. 3 without the slide closure;
FIG. 7 is a vertical section taken on line 7--7 of FIG. 4;
FIG. 8 is an enlarged rear elevation of the slide closure for the otoscope;
FIG. 9 is a vertical section on line 9--9 of FIG. 8 with the lens not in section;
FIG. 10 is a horizontal section on line 10--10 of FIG. 8 with the lens not in section;
FIG. 11 is a rear elevation of the lens for the slide closure;
FIG. 12 is an end elevation of the lens; and
FIG. 13 is a top plan view of the lens.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Having reference now to the drawings, the otoscope, generally indicated by the reference number 15, is mounted on a battery handle 16 of the type shown in U.S. Pat. No. 3,071,747, issued Jan. 1, 1963 to W. C. Moore, one of the applicants herein. The battery handle is held by the physician in using the instrument, and contains batteries (not shown), a switch button 17 and a rheostat dial 18. The batteries supply power to a lamp 19, FIG. 7, mounted in a metal sleeve 20 which forms the otoscope base.
The otoscope is essentially comprised of a head portion 21 and a speculum portion 22 and preferably has a unitary or one-piece molded plastic construction. The head portion 21 has a substantially rectangular configuration in rear elevation, FIG. 6, and its three-dimensional shape is that of a trapezoidal polyhedron as best shown in FIGS. 3 and 4. The speculum portion 22 has a substantially frusto-conical configuration although its wall elements have a slightly concave curvature as indicated in FIGS. 3 and 4. The head portion includes a cylindrical lug 24, FIG. 7, which is fixed as by epoxy cement to a tubular throat piece 25 and the base sleeve 20.
The otoscope is formed with a viewing passage 26 which extends continuously through its head and speculum portions. This passage is encircled at the distal end 27 thereof by a pre-formed bundle 28 of clad light transmitting optical fibers, FIGS. 5 and 7, embedded in the otoscope wall. Near the proximal end of the instrument, the fiber bundle becomes cylindrical in shape and extends centrally down through lug 24 terminating in an optically ground and polished surface 29. The bundle end 29 is adapted to receive light from the lamp 19, the light being emitted in a substantially annular pattern at the distal end of the otoscope to illuminate the field of view.
As indicated in FIG. 1, the otoscope speculum portion is provided with a detachable hollow tip 30 which forms an extension of the viewing passage 26 in order to protect the fiber ends at 27 and space them from the area under examination. This tip is formed with a rounded or bulbous distal end 30a to effect a good seal between the tip and wall of the ear canal. The inside of the tip has a small lug (not shown) which engages a slot 31 in the speculum portion to releasably secure the parts together. The fiber bundle arrangement and detachable passage extending tip are not considered to be novel per se having been disclosed in U.S. Pat. No. 3,146,775, issued Sept. 1, 1964 to applicant Moore and another.
In accord with the invention, the otoscope is formed with a relatively large, rectangular opening 32 at its proximal or rear end, FIGS. 6 and 7, which opening communicates with the viewing passage 26 through the instrument. This opening extends completely across the proximal end of the instrument as best shown in FIGS. 1 and 3, and the upper and lower edges of the opening are undercut as at 34 to provide guide ways for a slide closure generally indicated by the reference number 35 and shown in FIGS. 1, 3 and 8-10.
The slide closure comprises a suitable lens 36, FIGS. 11-13, which may be a magnifying lens, and a lens frame 37 made of a relatively soft elastomer material. Frame 37 is formed with a continuous interior channel 38 for receiving the peripheral edge of the lens, and its upper and lower edges are outwardly flared as at 39 for dovetailed engagement with the undercut edges 34. The closure can thus be engaged with or disengaged from the otoscope by an endwise or lateral sliding movement and to this end, an elastomer with a low coefficient of friction is employed to facilitate the sliding.
The elastomer frame 37, because of its elasticity and relative softness, makes total contact with the portions of the otoscope head it engages - even if there should be an irregularity or roughness in the material of the head - and insures an airtight seal between the closure and otoscope when the latter is to be used as a closed head or pneumatic type instrument. The frame of elastomer material thus actually operates as a gasket between the relatively movable lens and otoscope while at the same time serving as a protective support for the lens.
With the slide closure 35 in position in the otoscope, and with the tip 30 in substantially airtight engagement with the walls of the ear canal, air can be introduced into the latter by means of the pneumatic attachment of FIG. 2. This comprises a compressible inflation bulb 40 and a flexible connecting tube 41, the latter having an end fitting 42 that is insertable in a hole 44 through the wall of the otoscope head portion.
The relatively wide proximal end opening 32, FIG. 6, permits binocular vision in examining the illuminated field adjacent the distal end of the instrument, and this is true also when the slide closure 35 is in position because the usable portion of its lens is nearly as large as the usable portion of the opening, compare FIGS. 6 and 8. With the closure removed, the wide and relatively large opening 32 permits another instrument to be introduced into the passageway 26 without seriously obstructing the physician's vision. In this connection, the closure can if desired be displaced laterally just enough to permit the insertion of a slender auxiliary instrument, the closure in this case continuing to occupy most of the opening whereby the viewing is done through its lens. With a completely removable closure as disclosed herein, it will, of course, be apparent that an instrument can be provided with a number of interchangeable frames having lenses or the like of different characteristics. In addition, the instrument can be provided with a telescope attachment, a photographic adapter or the like.
From the foregoing description of the preferred embodiment of the invention, it will be apparent that an otoscope construction has been disclosed which provides substantial improvements over the prior art, the construction being at the same time economical to produce and efficient in operation.