9. Medical Applications 193
Optics for illuminating and
detecting light from object
Figure 9.5 Configuration of a fiber optic sensor system.
microtube, tilted surface, moving mechanical part, etc.) . Microbial
biosensors may also incorporate transducers which convert biochemical
signals into electrical or optical signals. Some sensors place immobilized
micro-organisms close to a thermistor which measures the metabolic heat
they produce; calorimetry may be applied to measure a large variety of
substances based on thermal reactions such as this. Some sensors work in
conjunction with microchips. For example, Oak Ridge National Labora-
tory has developed an infrared microspectrometer. It can be used for blood
chemistry analysis, gasoline octane analysis, environmental monitoring,
industrial process control, aircraft corrosion monitoring, and detection of
chemical warfare agents. It uses a light source to excite chemicals in
its environment, then channels the emitted light into an optical fiber for
external analysis. The measured wavelengths are fed into a microchip,
which identifies and determines the concentrations of chemicals in a sam-
ple. These miniaturized devices can be as accurate as standard laboratory
procedure, with a large number of additional applications . Finally,
we should note that there are many other types of biosensors that use
microchips, or illuminate using fluorescence, which do not require optical
 Hecht, J. (1999) City of Light: The story of Fiber Optics, Oxford University Press.
 Winawer, S.J., Fletcher, R.H., Miller, L., Godlee, F., Stolar, M.H., Mulrow, C.D.,
et al. (1997) “Colorectal Cancer Screening: Clinical Guidelines and Rationale”. Gas-
troenterology, 112: 594–642 (Published erratum in Gastroenterology 1997;112:1422).
 Bongsoo, L. (2004) Fiberoptic Tutorial, Nanoptics Inc. May 6.
194 Fiber Optic Essentials
 Dennis C. Leiner (2002) Miniature Optics in the Hospital Operating Room, Light-
house Imaging Corporation.
 Johnson, B.A. (1999) “Flexible Sigmoidoscopy: Screening for Colorectal Cancer”,
American Family Physician, January 15. American Academy of Family Physicians.
 Reinhard, J. (2000) Fundamentals of Fiber Optics (for Illumination), Volpi AG.
 Jerome D. Waye (2001) The Evolution of Gastrointestinal Endoscopy at The Mount
Sinai Hospital, The Mount Sinai Journal of Medicine, 68 (2), March.
 Nathan, R., Annetine C. Gelijns, and Holly, D. (1995) Sources of Medical Technol-
ogy: Universities and Industry, National Academy Press.
 Basil I. Hirschowitz (2000) “Endoscopy – 40 Years since Fiber Optics”, Digestive
 Gregory, A., Michael, K., Harvey, W., Thomas Cox, J., Elliott, L., Jame McCaughan
Jr., Brian, S., Raymond, L., Overview of Clinical Laser Applications, The Laser
Training Institute, www.lasertraining.org/Clinical Laser Applications.PDF.
 For lasers in eye surgery, see http://www.lasersite.com/lasik/index.htm.
 For lasers in dental surgery, see http://www.dentalfind.com/laser_gum_surgery/.
 Website for Clark Equine Clinic, http://www.clarkequine.com/surgery.htm.
 Alison, P. (2004) “KTP laser shows high efficacy in men with retention”, Urology
Times, January 1.
 “Breakthrough Treatment for Enlarged Prostate”, Surgical Center of Central Florida,
website feature article, http://www.thesurgicalcenter.net/Feature.html.
 McLeish, T. (2000) “Devices Detect Salmonella, E. Coli, Other Bacteria”, News-
wise, June 26. University of Rhode Island, Kingston R. I.
 Bruce, J.K. (1996) “Biosensors and Other Medical and Environmental Probes”,
ORNL Rev., 29 (3), Oak Ridge National Laboratory. http://www.ornl.gov/info/ornl-
review/rev29_3/text/biosens.htm; also, see http://www.microfab.com/technology/