Early Cancer Detection with Thermal Imaging
August 1, 2014
Despite many new drugs and therapeutic procedures in the field of oncology, the earliest possible detection of cancer is still the best method of giving patients the best chance of battling the disease.
Scientists from the Łódź University of Technology in central Poland are working on an early detection method based on thermal imaging. This makes it possible to pinpoint temperature anomalies in a patient’s body that may indicate disease.
The military uses thermal imaging to locate objects, and builders use it to examine the thermal insulation of buildings. Thermal imaging is also used in the power industry, metallurgy, the automotive sector, and environmental protection.
Thermal imaging measurements have many advantages. The method is fast, efficient, non-invasive, and does not require touching the object or body under examination. Thanks to a thermal imaging camera, it is possible to see the temperature distribution with a very high resolution, in the order of millikelvins (mK). This means that the camera operator can distinguish temperature fluctuations of just 0.1 degrees Celsius. Such a high resolution makes it possible to capture various anomalies, which is particularly important in medicine. The ability to precisely determine temperature levels and their distribution along the surface of the body provides information about the state of the patient’s health. The Łódź scientists have developed a new thermal imaging camera that allows doctors to detect trouble spots near the surface of the skin.
Commonly available infrared cameras are not suitable for use in medicine for a number of reasons. One of these is the need to calibrate the system using the shutter. Every now and then the shutter obstructs the image like a blinking eyelid. In many medical cases, it is necessary to examine the thermal process over time, and the shutter obstructing the image hinders this. In one routine examination, a patient’s limb is cooled slightly and then monitored with the camera to see how quickly the temperature returns to normal. On this basis, doctors can draw conclusions about the condition of the patient’s blood vessels, blood circulation and thermoregulation of the body. In such a case, continuous operation of the system without interruptions is needed.
The Łódź camera meets these requirements. It is extremely sensitive and has a high-contrast image. It employs new techniques, special electronic circuits and corrective algorithms, ensuring continuous temperature measurement. The camera also has special stabilizing mechanisms.
“Special software is very important,” says Prof. Bogusław Więcek, head of the Electronic Circuits and Thermography Division at the Łódź University of Technology. Thanks to this, completely new methods are being implemented for processing signals and images for conducting screening studies in various fields of medicine. Thermal imaging is ideal for screening various diseases and disorders, including skin cancer, where there are superficial vascular lesions. There is a great demand for diagnosis of melanoma, or skin cancer. In the case of various cancers, new blood vessels are created that cause a different blood flow, so after cooling, the heat reaction of the body is different than the response of healthy tissue. A suspicious trouble spot is cooled and then the temperature rise is examined. With this method it will be possible to perform non-invasive screening tests for early detection of various diseases, including cancer. After examining a statistically significant number of cases it will be possible to confirm the effectiveness of such tests.
Thermal imaging is beginning to play an increasingly important role in medicine. It helps detect inflammatory conditions that involve an elevated temperature, for example in orthopedics. In many hospitals around the world, thermal imaging monitoring is used during cardiac surgery.
An important field in which an infrared camera is useful is the treatment of burns. The size and depth of this type of injury is monitored as well as the entire healing process and time.
The Łódź researchers are also working on applying this method to detect breast cancer. According to Więcek, thermography could be complementary to mammography and ultrasound methods, especially among younger women, in whom early detection of cancer usually ensures successful treatment. Więcek quotes yet another argument: the camera designed by the Łódź researchers costs zl. 20,000-30,000 to produce, while a mammography unit costs more than zl. 1 million.
A prototype of the new thermal imaging camera was produced some time ago using funds from a development grant. At the moment, the team, which also includes doctors from the Military Medical Institute in Warsaw, scientists from the Gdańsk University of Technology and partners from Portugal, Britain, Belgium, Ukraine and Greece, is taking on a large European project as part of a consortium with companies interested in using the new thermal imaging camera in medical practice.
Danuta K. Gruszczyńska