A catheter device having a proboscis, such as a needle, and a transducer which detects the axial displacement of the proboscis in relation to the distal tip of the catheter. The transducer is positioned at a distal portion of the catheter and may comprise an induction coil or a potentiometer. Axial displacement of the proboscis changes the amount of inductance or resistance in the transducer. This change in inductance or resistance can be calibrated to the amount of axial displacement of the proboscis and provided as feedback to the user.
