An optical coherence tomography (OCT) imaging probe 500 comprises a reference arm, and a sample arm which are both preferably disposed in a hollow outer tube 515. The sample arm comprises a MEMS scanning mirror 210 disposed inside and secured to the tube 515 for providing lateral scanning of a first and second optical beam provided. The scanning mirror has a highly reflective top 211 and highly reflective bottom surface 212, wherein the first beam is incident on the top surface and the second beam is incident on the bottom surface. The scanning mirror 210 is rotatable through at least 90.degree. along a first axis to provide 180.degree. scanning on each of its surfaces to cover a full 360.degree. circumferential view of a sample to be imaged.