Marker for radiology

Claim 2

For use in radiographic procedures utilizing a source of Xradiation and an X-radiation-sensitive film, the source and the film being movable about a predetermined line disposed between the source and film to produce a visible image only of objects lying on a plane passing through said line, a marker for indicating the location of said plane relative to a reference surface having a known position parallel to the plane of said film and said plane passing through said line, said marker comprising: a radiolucent member having an upwardly facing edge adapted to be positioned within the field of radiation and overlying the film, said edge presenting a plurality of contiguous steps in vertically planar alignment having a plurality of upwardly facing surfaces at different elevations, each of said elevations corresponding to a possible location of said plane vertically of said reference surface; and a series of radio-opaque indicia disposed on said surfaces, each indicium designating a particular surface on which it is located whereby the indicium closest to the plane when the film is exposed to the radiation is recorded on the film while the remaining indicia are blurred as a result of movement of the source and film.

Claim 3

For use in radiographic procedures utilizing a source of X-radiation and an X-radiation-sensitive film, the source and the film being movable about a predetermined line disposed between the source and film to produce a visible image only of objects lying on a plane passing through said line, a marker for indicating the location of said plane relative to a reference surface having a known position parallel to the plane of said film and said plane passing through said line, said marker comprising: a radiolucent member having an upwardly facing edge adapted to be positioned within the field of radiation and overlying the film, said edge presenting a plurality of contiguous steps in vertically planar alignment having a plurality of upwardly facing surfaces at different elevations, each of said elevations corresponding to a possible location of said plane vertically of said reference surface; and a series of radio-opaque indicia disposed on said surfaces, each indicium designating a particular surface on which it is located whereby the indicium closest to the plane when the film is exposed to the radiation is recorded on the film while the remaining indicia are blurred as a result of movement of the source and film.

Claim 4

For use in radiographic procedures utilizing a source of X-radiation and an X-radiation-sensitive film, the source and the film being movable about a predetermined line disposed between the source and film to produce a visible image only of objects lying on a plane passing through said line, a marker for indicating the location of said plane relative to a reference surface having a known position parallel to the plane of said film and said plane passing through said line, said marker comprising: a radiolucent member having an upwardly facing edge adapted to be positioned within the field of radiation and overlying the film, said edge presenting a plurality of contiguous steps in vertically planar alignment having a plurality of upwardly facing surfaces at different elevations, each of said elevations corresponding to a possible location of said plane vertically of said reference surface; and a series of radio-opaque indicia disposed on said surfaces, each indicium designating a particular surface on which it is located whereby the indicium closest to the plane when the film is exposed to the radiation is recorded on the film while the remaining indicia are blurred as a result of movement of the source and film.

Claim 5

The invention of claim 1, wherein said member is provided with a second one of said edges, the indicia for one of said edges being at higher elevations than the indicia for the other edge.

Claim 6

The invention of claim 2, wherein each stepped edge is configured to present a slope extending at an angle from the vertical, and wherein the slopes of said edges extend in opposite directions.

Claim 7

The invention of claim 1, and means associated with the member for supporting the latter in a predetermined position with respect to said reference surface.

Claim 8

The invention of claim 4, wherein said supporting means includes a suction cup adapted to be releasably secured to said reference surface, and means securing said suction cup to the member.