Patent ID: 7699522

Claim:
A medical imaging quality assurance device, comprising: a housing, said housing having a housing wall encircling a hollow interior chamber, said interior chamber having a chamber longitudinal axis, and said chamber having a chamber cross-sectional geometry and area measurable perpendicular to said chamber longitudinal axis, and said chamber cross-sectional geometry and area being constant between two longitudinally spaced apart points; a rod member having a proximal end portion and a distal end portion, said distal end portion of said rod member being slideably disposed inside of said interior chamber between said two longitudinally spaced apart points; a first marker, said first marker being disposed in said distal end portion of said rod member, wherein said first marker comprises a discontinuity in said distal end portion of said rod member; a plurality of second markers disposed in said wall of said housing, wherein each of said plurality of second markers comprises a discontinuity in said housing; and means for attaching said proximal end portion of said rod member to a motion actuator.