A system for assessing effects of ablation therapy on tissue in a body, comprising: a) an ultrasound transducer configured to generate ultrasound images and to deliver ultrasound ablative energy to tissue; b) an optic fiber configured to emit electromagnetic radiation to the tissue; and c) an electronic control unit including the following: an imaging module configured to operate the ultrasound transducer in a first mode to generate and acquire at least one ultrasound image from the tissue within a region of interest within the body; a tracking module configured to identify and track the region of interest within the at least one ultrasound image and confirm that the tissue remains within the region of interest; a therapy module configured to generate a signal to cause the ultrasound transducer to operate in a second mode to deliver ultrasound ablative energy to the region of interest; a radiation module configured to generate a signal to cause the optic fiber to emit electromagnetic radiation to cause generation of a photoacoustic wave from tissue in the region of interest; a tissue sensing module configured to receive a tissue response signal indicative of a characteristic of tissue responsive to the electromagnetic radiation; and an analysis module configured to analyze the tissue response signal to determine at least one characteristic of the tissue responsive to the ablation therapy. a) an ultrasound transducer configured to generate ultrasound images and to deliver ultrasound ablative energy to tissue; b) an optic fiber configured to emit electromagnetic radiation to the tissue; and c) an electronic control unit including the following: an imaging module configured to operate the ultrasound transducer in a first mode to generate and acquire at least one ultrasound image from the tissue within a region of interest within the body; a tracking module configured to identify and track the region of interest within the at least one ultrasound image and confirm that the tissue remains within the region of interest; a therapy module configured to generate a signal to cause the ultrasound transducer to operate in a second mode to deliver ultrasound ablative energy to the region of interest; a radiation module configured to generate a signal to cause the optic fiber to emit electromagnetic radiation to cause generation of a photoacoustic wave from tissue in the region of interest; a tissue sensing module configured to receive a tissue response signal indicative of a characteristic of tissue responsive to the electromagnetic radiation; and an analysis module configured to analyze the tissue response signal to determine at least one characteristic of the tissue responsive to the ablation therapy. an imaging module configured to operate the ultrasound transducer in a first mode to generate and acquire at least one ultrasound image from the tissue within a region of interest within the body; a tracking module configured to identify and track the region of interest within the at least one ultrasound image and confirm that the tissue remains within the region of interest; a therapy module configured to generate a signal to cause the ultrasound transducer to operate in a second mode to deliver ultrasound ablative energy to the region of interest; a radiation module configured to generate a signal to cause the optic fiber to emit electromagnetic radiation to cause generation of a photoacoustic wave from tissue in the region of interest; a tissue sensing module configured to receive a tissue response signal indicative of a characteristic of tissue responsive to the electromagnetic radiation; and an analysis module configured to analyze the tissue response signal to determine at least one characteristic of the tissue responsive to the ablation therapy.