Louis Ellis, Roger N Hastings, Ling Shang: Balloon inflation measurement apparatus. SciMed Life Systems, Nawrocki Rooney & Sivertson, March 14, 1995: US05397308 (108 worldwide citation)

An improved balloon catheter for angioplasty and the like for measuring the inflation of a balloon after insertion into the body. A pair of electrodes are mounted in spaced relation within the balloon interior wall such that as the internal area within the balloon is varied by inflation of the ballo ...