Micromirror-scanned dual-axis confocal microscope utilizing a gradient-index relay lens for image guidance during brain surgery

• Published in: Journal of Biomedical Optics Vol. 15; no. 2; p. 026029
• Main Authors: Liu, Jonathan T, Mandella, Michael J, Loewke, Nathan O, Haeberle, Henry, Ra, Hyejun, Piyawattanametha, Wibool, Solgaard, Olav D, Kino, Gordon S, Contag, Christopher H
• Format: Journal Article
• Language: English
• Published: United States Society of Photo-Optical Instrumentation Engineers 01-03-2010
• Subjects: Algorithms; Animals; Brain; Confocal; Craniotomy - instrumentation; Fluorescence; Image Enhancement - instrumentation; Lenses; Mice; Microelectromechanical systems; Microscopy, Confocal - instrumentation; Miniaturization; Relay; Reproducibility of Results; Research Papers: Imaging; Sensitivity and Specificity; Surgery, Computer-Assisted - instrumentation
• ISSN: 1083-3668; 1560-2281
• DOI: 10.1117/1.3386055

A fluorescence confocal microscope incorporating a 1.8-mm-diam gradient-index relay lens is developed for
histological guidance during resection of brain tumors. The microscope utilizes a dual-axis confocal architecture to efficiently reject out-of-focus light for high-contrast optical sectioning. A biaxial microelectromechanical system (MEMS) scanning mirror is actuated at resonance along each axis to achieve a large field of view with low-voltage waveforms. The unstable Lissajous scan, which results from actuating the orthogonal axes of the MEMS mirror at highly disparate resonance frequencies, is optimized to fully sample 500×500 pixels at two frames per second. Optically sectioned fluorescence images of brain tissues are obtained in living mice to demonstrate the utility of this microscope for image-guided resections.