The present invention is a single apparatus that can be adjusted through a range of diameters to measure an anatomical tissue annulus. The apparatus includes an elongated support member having a proximal end and a distal end. An operator actuated movable member is joined to the proximal end of the...http://www.google.ca/patents/US5814098?utm_source=gb-gplus-sharePatent US5814098 - Adjustable sizing apparatus
