Design of an Endoscopic Raman Probe for Detection of Ovarian Cancer Elizabeth Kanter Matt Keller Vanderbilt University Advisor: Dr. Anita Mahadevan-Jansen VU BME

Goals Gain comprehensive understanding of Raman spectroscopy and basic understanding of ovarian physiology Research design limitations imposed by laparoscope and physiological environment Come up with innovative probe design to allow detection of ovarian cancer Implement design for clinical use

Raman Scattering Photons collide inelastically with scattering molecule Molecule enters virtual excited vibrational state, then returns to lower state Photon of lower frequency re- emitted

Raman Spectrum Plot of signal intensity vs. shift in wavenumber Very weak signal, compared to fluorescence Peaks narrow and highly specific to particular bonds (diff between normal & cancerous tissue)

Ovarian Cancer Lifetime odds of developing are 1/70 Family history biggest risk factor: 3.6 times more likely to develop ovarian cancer if have primary relative afflicted Asymptomatic until final stages, so need reliable, minimally invasive early detection method for women at risk Current detection methods (pelvic & rectal exam, ultrasonography, biopsy) either not reliable for early detection or too invasive

Benefits & Problems of Our System Minimally invasive One-time cost for clinics Reliable early detection Must remain flexible and fit in laparoscopic tubing (< 5 mm) Must be able to visualize location of probe Must read only the Raman signal

Current Probe Designs

Central fiber-laser fiber Surrounding fibers- collection fiber Each fiber has a filter on the bottom, either notch or band pass

Current Work Finding availability of micro-optical parts needed – Band-pass filters, notch filters, fiber coatings Discussing laparoscopic developments with gynecologists

Future Work Build large-scale models to test design Scale down best design to fit in laparoscope Clinical trials

References Frank, C.J., Redd, D. C., Gansler, T.S, McCreedy, R.L. “Characterization of Human Breast Biopsy Specimens with Near- IR Raman Spectroscopy” Analytical Chemistry, 66, (1994) Mahadevan-Jansen, A., Raman Spectroscopy: From Bench top to Bedside. (2002) National Cancer Institute