An opto-acoustic probe comprising: an acoustically transmissive optical distribution element comprising: a distal surface configured to couple to a volume of a biological tissue to deliver optical energy to the volume and to exchange acoustic energy with the volume; and, a proximal surface proximate to an acoustic receiver , the acoustically transmissive optical distribution element configured to permit acoustic energy originating within the volume based on the optical energy delivered, to pass through the acoustically transmissive optical distribution element to be detected by the acoustic receiver; wherein the acoustically transmissive optical distribution element is configured to receive the optical energy at one or more optical energy inputs from an optical energy path of the probe, and the acoustically transmissive optical distribution element is configured to distribute the optical energy received at the one or more optical energy inputs from the optical energy path to the distal surface, so that the optical energy distributed exits the distal surface of the acoustically transmissive optical distribution element wherein the optical distribution element is configured to absorb at least a portion of the optical energy to produce a secondary acoustic return that interferes with a direct acoustic return component originating from the volume, wherein the opto-acoustic probe is operatively connected to an opto-acoustic system comprising a processing unit adapted to separate the secondary acoustic return from the direct acoustic return component using a component separation, and the system comprises a display to display an image based on the separated direct acoustic return component; and wherein the optical distribution element comprises an optically diffusing fiber. an acoustically transmissive optical distribution element comprising: a distal surface configured to couple to a volume of a biological tissue to deliver optical energy to the volume and to exchange acoustic energy with the volume; and, a proximal surface proximate to an acoustic receiver , a distal surface configured to couple to a volume of a biological tissue to deliver optical energy to the volume and to exchange acoustic energy with the volume; and, a proximal surface proximate to an acoustic receiver , the acoustically transmissive optical distribution element configured to permit acoustic energy originating within the volume based on the optical energy delivered, to pass through the acoustically transmissive optical distribution element to be detected by the acoustic receiver; wherein the acoustically transmissive optical distribution element is configured to receive the optical energy at one or more optical energy inputs from an optical energy path of the probe, and the acoustically transmissive optical distribution element is configured to distribute the optical energy received at the one or more optical energy inputs from the optical energy path to the distal surface, so that the optical energy distributed exits the distal surface of the acoustically transmissive optical distribution element wherein the optical distribution element is configured to absorb at least a portion of the optical energy to produce a secondary acoustic return that interferes with a direct acoustic return component originating from the volume, wherein the opto-acoustic probe is operatively connected to an opto-acoustic system comprising a processing unit adapted to separate the secondary acoustic return from the direct acoustic return component using a component separation, and the system comprises a display to display an image based on the separated direct acoustic return component; and wherein the optical distribution element comprises an optically diffusing fiber. <EOS>