The present invention in some embodiments thereof relates to a method for selectively modifying nerve activity without causing substantial damage to non-targeted tissue, comprising introducing a catheter device comprising one or more ultrasonic transceivers to the pulmonary artery lumen, receiving, using the one or more ultrasonic transceivers, echo signals reflected from the non-targeted tissue following emission of ultrasound energy by the one or more transceivers, analyzing the received echo signals to identify at least one of a type and location of the non-targeted tissue relative to the one or more transceivers, and emitting ultrasound energy from the one or more ultrasonic transceivers in accordance with the analysis, to modify nerve activity without substantially damaging the identified non-targeted tissue.
