Abstract: An apparatus for the determination of the inner dimensions of hollow organs, in particular the cavum uteri [uterus cavity], has at its forward end thereof a tube-like probe (10) with two divergable probe tips (32). The probe tips (32) can be spread apart by a translational element which is positioned coaxially within the probe (10). The probe tips (32) are designed as two arms or levers and are attached to two pivots at the forward tip of the probe (10). The translational element is applied behind the pivot points of the probe tips (32). The distance of separation of the probe tips (32) is indicated on a gauge (14).

Abstract: A sound or probe for determining the internal measurements of hollow organs and hollow parts of, for example, humans includes two rod shaped spring elements at the head of the sound which in turn are attached at their one end in an axial direction with their unattached ends spreading apart upon release of tension and with a thread under tensile stress connecting the spring elements and being guided to their base by the sound with means being provided for indicating the actual distance between the ends of the spring elements in accordance with the relative shifting position of the thread and sound.