bmdo technologies for biomedical applications - MDA Technology

OPTICAL BIOPSYBMDO HISTORYFunding for surface-enhanced Raman optical data storage (SERODS) at OakRidge National Laboratory (ORNL) also led to a different sort of biologicalprobe (see previous article on SERGen). Tuan Vo-Dinh, Ph.D., conductedstudies with SERODS-associated lasers that have contributed to the use oflasers for a cancer detection method that substitutes light for the scalpel ofsurgical biopsy. Using the body’s own emissionin reaction to certain wavelengths of laserThe average age of alight, it is possible to detect unique fluorescencesignals with a spectrometer. As demonstratedin studies conducted by Vo-Dinh atcancer patient at diagnosisis 60; this fact probably ORNL and his co-developers, MasoudPanjehpour, M.D. and Bergein Overholt,reflects long-term exposureto environmental demonstrate cancerous “hot spots” withoutM.D., at the Thompson Cancer SurvivalCenter (Knoxville, TN), this activity canremoving tissue. Optical biopsy, as this techniquehas come to be known, has gainedinsults and carcinogens,tremendous momentum within the last twoas well as the aging body’syears. Major trials are under way in manydeclining ability to repair U.S. cancer treatment centers, such asMemorial-Sloan Kettering (New York, NY),genetic mutations. Roswell Park (Buffalo, NY), WellmanLaboratories of Photomedicine (Boston, MA),and Beckman Laser Institute (Irvine, CA).58• Optical biopsy holds the key to earlycancer diagnosis.HOW IT WORKSThe tissue under investigation is illuminated with laser light via a fiberopticprobe. Electrons in the tissue are temporarily kicked into a higherquantum state, or energy level; when they relax to a lower energy level,photons are emitted for a short time (fluorescence). A spectrometer recordsthe wavelength of the fluorescence. Cancerous tissue fluoresces at peakwavelengths different from those seen in normal tissue. By comparing thepeak readings, the fluorescence signatures can be converted into a realcolorimage that shows precisely where normal tissue ends and canceroustissue begins. This method is also sensitive to precancerous changes andinflammation.MEDICAL SIGNIFICANCEEarly diagnosis is the key to effective therapy and long-term cancer survival.Optical biopsy can help to diagnose cancers before they have had achance to spread and can also alert the clinician to precancerous conditionsthat can thereafter be carefully monitored. Slender fiber-optic lightdelivery can also reach hard-to-access regions, can be used with conven-Chapter 2 - Observation TechnologiesSection C - DiagnosisBMDO Technologies for Biomedical Applications