A system and method for tracking and determining characteristics of an inflatable medical instrument that is configured for interventional deployment. The system includes a guidewire that is positioned within a lumen of the inflatable medical instrument. The guidewire includes an optical fiber for a FORS system. The FORS system is configured to measure a shape of the guidewire during the interventional deployment of the inflatable medical instrument. A shape analysis module is configured to analyze the FORS data from the FORS system and determine characteristics of the inflatable medical instrument, including the diameter of the inflatable instrument, the pressurization of the instrument, whether the instrument has ruptured and the position of the inflatable instrument during an interventional procedure.