a balloon catheter includes an elongate pliable catheter tubing with a dilatation balloon fixed to the catheter tubing near its distal end . the dilatation balloon includes a first wall for dividing the balloon into a plurality of dilatation compartments adjacent one another and arranged angularly about the catheter tubing . each dilatation compartment is fluid tight and in fluid isolation from other compartments . the compartments are individually controlled so the pressure within each balloon compartment may be adjusted as determined by the operator . the dilatation balloon includes a second wall composed of the respective outer wall portions of the dilatation compartments which defines an outer transverse profile of the dilatation balloon and adapted to form surface engagement with the tissue segments surrounding the balloon when the compartments are dilatated . the exterior surface of the balloon dilatation compartments include pressure sensing apparatus mounted thereon and adapted for positioning between the second wall and the tissue wall segment during surface engagement for measuring the pressure between the dilatation balloon and the tissue wall segment . the balloon compartments are individually controlled so the pressure within each balloon compartment may be adjusted by the operator . alternative embodiments include thin film heating elements located on the exterior surface , thin film transducers having an ultrasonic imaging capability located on the exterior surface , drug delivery capabilities and a dual balloon arrangement .