Exemplary imaging apparatuses are described. Various embodiments of the imaging apparatuses may implement optical coherence tomography (OCT) and/or optical frequency domain imaging (OFDI) tissue imaging technologies, with the capability to perform tissue retrieval at the same time. Furthermore, the imaging apparatuses may include a rotatable imaging element to scan a bodily lumen, such as the bile duct. The imaging element may be housed within a cylindrical window. Still further, the imaging apparatuses may include an ancillary channel. The ancillary channel may provide access to the tissue in the bile duct, or other bodily lumen.
