Portable optical resolution photoacoustic microscopy (pORPAM) for human oral imaging

Optical resolution photoacoustic microscopy (ORPAM) represents one of the fastest evolving optical microscopic techniques. However, due to the bulky size and complicated system configuration of conventional ORPAM, it is largely limited to small animal experiments. In this Letter, we present the design and evaluation of a portable ORPAM with a high spatiotemporal resolution and a large field of view. In this system, we utilize a rotatory scanning mechanism instead of the conventional raster scanning to achieve translationless imaging of the probe/samples, making it accessible to the human oral lip and tongue. After phantom evaluation, we applied this system to monitor longitudinal neo-angiogenesis of tumor growth and, for the first time, to the best of our knowledge, image the oral vascular network of humans to show its potential in clinical detection of early-stage oral cancer.