A cannula and method include a shaft portion having a proximal end, a distal end, a longitudinal axis and a lumen extending from the proximal end to the oppositely disposed distal end along the longitudinal axis. A hub is attached to the proximal end of the shaft portion and includes a transverse portion, which extends transversely relative to the longitudinal axis of the shaft portion. An opaque marker is disposed on the transverse portion at a position corresponding to an expanded size of an expandable element such that the opaque marker indicates the expanded size in an imaging system image.