A handheld microscope integrating photoacoustic microscopy and optical coherence tomography

The combination of optical resolution photoacoustic microscopy (ORPAM) and optical coherence tomography (OCT) is capable of providing complementary imaging contrasts. Unfortunately, the miniaturization of ORPAM remains a major challenge in the development of a handheld dual-modality imaging microscope with OCT. Here, we report the design and evaluation of an integrated ORPAM and OCT imaging probe using a two-dimensional MEMS (micro-electro-mechanical-system)-based optical scanner. This microscope, weighting 35.4 g, has an ultracompact size of 65 x 30 x 18 mm3, and an effective imaging area of 2 x 2 mm(2). The experimental lateral resolutions are 3.7 mu m (ORPAM) and 5.6 mu m (OCT), and the axial resolutions are measured as 120 mu m (ORPAM) and 7.3 mu m (OCT). Besides phantom and animal experiments, we carried out oral imaging of a healthy volunteer to show the clinical feasibility of this technique. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.