title: Visualizing epithelial expression of EGFR in vivo with distal scanning side-viewing confocal endomicroscope.
abstract: Confocal endomicroscopy is an emerging imaging technology that has recently been introduced into the clinic to instantaneously collect "optical biopsies" in vivo with histology-like quality. Here, we demonstrate a fast scanner located in the distal end of a side-viewing instrument using a compact lens assembly with numerical aperture of 0.5 to achieve a working distance of 100 μm and field-of-view of 300 × 400 μm2. The microelectromechanical systems (MEMS) mirror was designed based on the principle of parametric resonance and images at 5 frames per second. The instrument has a 4.2 mm outer diameter and 3 cm rigid length, and can pass through the biopsy channel of a medical endoscope. We achieved real time optical sections of NIR fluorescence with 0.87 μm lateral resolution, and were able to visualize in vivo binding of a Cy5.5-labeled peptide specific for EGFR to the cell surface of pre-cancerous colonocytes within the epithelium of dysplastic crypts in mouse colon. By performing targeted imaging with endomicroscopy, we can visualize molecular expression patterns in vivo that provide a biological basis for disease detection.
authors.affiliation: Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Xiyu
authors.initials: X
authors.lastname: Duan
authors.affiliation: Department of Internal Medicine, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Haijun
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Internal Medicine, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Juan
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Quan
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Kenn R
authors.initials: KR
authors.lastname: Oldham
authors.affiliation: Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.|Department of Internal Medicine, University of Michigan, Ann Arbor, MI, 48109, USA.|Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Wang
mesh_terms: D000818:Animals; D002232:Carbocyanines / Q000737:chemistry; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D066246:ErbB Receptors / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000378:metabolism*; D051379:Mice; D055617:Micro-Electrical-Mechanical Systems; D018613:Microscopy, Confocal / Q000379:methods*; D015203:Reproducibility of Results; D059008:Time-Lapse Imaging / Q000379:methods
chemical_list: C098793:CY5.5 cyanine dye; D002232:Carbocyanines; D066246:ErbB Receptors