A device (10) is provided for ultrasound-based reflection and transmission tomography. The device (10) comprises: a transducer holder (14) configured to hold a plurality of ultrasonic transducers around an imaging volume (30) to be filled with an ultrasonic coupling medium, the transducer holder (14) having an opening for inserting, into the imaging volume (30), at least one part of a body to be imaged, wherein the transducer holder (14) is configured to move, during imaging of the at least one part of the body to be imaged, with respect to the body to be imaged; a support member (11) configured to support, during imaging, the body to be imaged, the support member (11) having a support-member-opening allowing access to the transducer holder (14) by the at least one part of the body to be imaged; a diaphragm (12) having a diaphragm-opening (13), the diaphragm (12) being arranged across the support-member-opening such that a center of the diaphragm-opening (13) is placed substantially at a predetermined position, wherein the diaphragm (12) comprises a material that has a higher transmissivity of ultrasound than a material of the support member (11); an outlet (15) for the ultrasonic coupling medium to flow out of the imaging volume (30) when the at least one part of the body to be imaged is inserted into the imaging volume (30) filled with the ultrasonic coupling medium and/or during imaging; and an elastic membrane (16) comprising a fluidtight material connecting the transducer holder (14) and the outlet (15) in order to guide the ultrasonic coupling medium flowing out of the imaging volume (30) towards the outlet (15).
