For centuries, humans have been mesmerized by the lights and sounds of lightning and thunder storms.

In 1880 Alexander Graham Bell observed a similar phenomenon in his lab, generating sound waves by exposing selenium cells to a modulated beam of light. He called his discovery the photophone, the first wireless telephone message. Today, the production of sound by optical interactions at the nanoscale, referred to as optoacoustic imaging and spectroscopy, is leading to new medical technologies including for cancer imaging.

Public lecture

A public lecture on the Memorial University St. John’s campus will explore these new technologies and their medical applications, all of which are positioned to have a significant impact on health care.

Dr. William Whelan, professor and chair of the Department of Physics, University of Prince Edward Island, is the inaugural speaker for the Dr. and Mrs. Satti Paddi and Parvati Reddy Memorial Lecture.

“Detecting cancer at its earliest stage remains a significant challenge,” said Dr. Whelan. “With optoacoustics, you shine pulsed laser light on cancer cells, and they emit a symphony of sounds. By measuring the time delay between this ‘lightning and thunder,’ one can locate a tumour inside the body.”

The pitch of the sound created depends on the size and shape of the target and the sound volume depends on the concentration of optical absorbers in the blood. By listening to the sounds, one can differentiate between normal and cancerous tissues, as well as treated and untreated tissues.

“With optoacoustics, you shine pulsed laser light on cancer cells, and they emit a symphony of sounds. By measuring the time delay between this ‘lightning and thunder,’ one can locate a tumour inside the body.” — Dr. William Whelan

Dr. Whelan’s research is in the field of biomedical optics with a focus on optoacoustic imaging and spectroscopy for cancer diagnosis and treatment monitoring. His laboratory developed point radiance spectroscopy, a technique that uses directional light measurements to recover tissue optical properties. He has co-authored more than 50 research papers and a book chapter on diagnostic and therapeutic uses of light in medicine, and has been a consultant to a number of biophotonics companies.

Thursday, April 7

His lecture, Optoacoustic Imaging and Spectroscopy: Lightning and Thunder in Tissues, takes place Thursday, April 7, at 7 p.m. in the Bruneau Centre for Research and Innovation, room IIC-2001. A reception will follow and free parking is available in lot 15B.

Dr. Whelan will also give a research seminar titled A Spectroscopy Toolbox for Cancer Detection and Therapy Guidance, on Friday, April 8, at 3 p.m. in the Chemistry-Physics building, room C-2045.

The Dr. and Mrs. Satti Paddi and Parvati Reddy Memorial Lecture Series was created to honour the research contributions of Dr. S.P. Reddy, professor emeritus and former head of the Department of Physics and Physical Oceanography. The purpose is to attract a well-spoken leader in physics research or discovery, providing wide-reaching benefit to the general public and university community.