Prostate cancer has become the most common form of cancer to affect men in the western world. And as the number of patients is growing, so is the need for new, reliable methods of examination.
At Umeå University, a recently started project studying the use of piezoelectric materials, is finding ways to increase accuracy as well as efficiency in diagnosing cancer.
The goal of the project Development of piezoelectric sensor for diagnosis and characteristics of cell changes in soft tissue, is to develop and increase the knowledge of piezoelectric materials.
Britt Andersson, university lecturer at the department for applied physics and electronics, is in charge of the project and explains the unique qualities of the piezo materials.
“A piezoelectric material can convert mechanical energy to electric energy and vice versa, which makes it useful in a number of applications.”
Today, piezoelectric materials are used in instruments for ultrasound, sensors and microphones, to name a few examples. Andersson and her colleagues are looking for a way to also be able to use the materials in tactile sensors, developed to examine soft tissue.
“Our job is to examine the piezoelectric materials, their structure and different qualities” she says, “one of the methods we use is simulations where we look at oscillations and their different properties.”
A piezoelectric material is made oscillating with its resonance frequency. Andersson’s team then measure how the frequency changes when the piezo material is put in contact with a different surface, for example biological tissue. This would make it possible to detect tumors since they tend to be harder than normal tissue. However, one of the problems is that variables such as temperature, age and electromagnetic fields can affect the qualities of the piezoelectric materials and it is essential that the sensors are stable, giving reliable measured values.
PZT (lead-zirconate-titanate), a ceramic material consisting of small, densely joint grains, is the most commonly used piezoelectric material today. It is also the material Andersson’s project spends the most time working with.
“There are many parameters to consider” says Andersson, “and all of them can play an important role. Shape, grain structure, temperature and how the material ages, are just some examples. ”
Within the project, they are also examining the possibilities to create their own piezoelectric materials, in order to get better control of these parameters.
As the sensor technique that is being developed reacts on differences in texture in biological tissue it could register these differences in forms of values on a predetermined scale. Such a numerical value would lead to increased efficiency as well as accuracy in the first phase of cancer diagnostics.
But the method can also prove useful in a later stage of cancer treatment. Surgeries, for example those performed in cases of prostate cancer, are complicated since it is easy to cause damage to contiguous nerves, something that can lead to severe complications for the patient. Therefore, it is important not to remove more of the prostate than needed. At the same time it is obviously necessary to remove all cancerous tissue. Currently, samples of the surgically removed tissue are being tested to assure the outer parts are free of cancer. But as the test results take a few days, a second surgery has to be performed if they prove to be positive. This is possibly where the new technique could prove most useful since it would enable immediate examination and result of the removed tissue.
The project has developed research within this kind of sensors that is unique worldwide and commercialized by BioResonator AB, a corporation formed by CMTF. The need for reliable, objective methods of measuring is great, as is the market within this field of diagnostics.
CMTF, c/o Tillämpad fysik och elektronik
Umeå universitet, 901 87 Umeå
Tel: +46 (0)90-786 96 38.
E-post: Britt Andersson.
