Abstract: A percutaneous treatment catheter comprises a canopy (12) having a treatment side adapted to provide at least one of a variety of treatments to a first tissue layer and a protection side that protects adjacent tissue from the treatment. Treatments include, but are not limited to, those that act to cause an inflammatory response resulting in forming scar tissue that would tend to form adhesions, such as, but not limited to, for the treatment of pleural effusions. In an embodiment, a treatment catheter comprises a shaft (20) having a shaft and a treatment head (10) disposed about the shaft distal end, the treatment head adapted to present a low profile in a closed state and a broad profile in a 10 deployed state, the treatment head adapted to percutaneously treat one of first and second tissue layers and protect the other of the first and second tissue layers from the treatment.