Thermography or thermology is the medical science that derives diagnostic indications from highly detailed and sensitive infrared images of the human body. Thermology is sometimes referred to as medical infrared imaging or tele-thermology and utilizes highly resolute and sensitive thermographic cameras.
Medical thermography is used to determine areas of the body that have irregular blood flow. It is commonly used by sport doctors and vetinarians to determine areas of the body that have inflammation. Thermography is also used by allergy clinics.
In alternative medicine
The use of thermography for breast cancer screening is highly controversial and the various medical bodies around the world differ in their opinions as to it's accuracy. It's often promoted by complementary and alternative medicine (CAM) clinics as an early warning breast imaging technique for cancer screening. Claims have been made that thermography has shown blood flow irregularities which eventually become tumours more than five years in advance of the onset of cancer. This claim is hotly disputed by radiologists. The American Cancer Society says:
Thermography has been around for many years, and some scientists are still trying to improve the technology to use it in breast imaging. But no study has yet shown that it is an effective screening tool for finding breast cancer early. It should not be used as a substitute for mammograms.
Although thermography is discouraged in North America by the American Cancer Society, radiologists and the FDA for early breast cancer detection, it is widely adopted in clinics in Europe. According to FLIR, the largest manufacturers of thermal cameras, there are several studies listed in Pub Med that suggest thermography can be used in addition to conventional radiotherapy. and their cameras are widely used in Europe as a medical device to determine early warning symptoms of breast cancer. 
Initial studies (1977) found it to be less useful than either mammography or clinical examination, and skeptics have noted that sites promoting breast thermography carry the "quack Miranda warning" that claims have not been evaluated by the U.S. Food and Drug Administration (FDA).
The FDA has issued a public warning notice stating that breast thermography is not an alternative to mammography and has ordered Joseph Mercola to stop making excessive claims for thermography.
The FDA licensed the FLIR thermography cameras on March 9, 2004 “for use as an adjunct to other clinical diagnostic procedures in the diagnosis, quantifying, and screening of differences in skin surface temperature changes” (K033967). The cleared indication for use statement also states that the FLIR Telethermographic camera Series A, E, P and S can “visualize and document temperature patterns and changes.”
Medical thermography of breasts are non-invasive and have no harmful effect unlike x-rays because they capture the infrared radiation "heat signature" that is emitted by the body. The photographs will show areas of the skin that are higher and lower in temperature as "hot spots". Breasts that show asymetrical skin temperatures between the two breasts are said to be "suspect" by professional thermographers. If these irregular heat signature should occur, they then advise the patient to follow up with a standard mammogram. Irregular heat patterns do not mean that the breast contains cancerous tumours. It means that there is increased blood flow to certain areas of the breast. This increased blood flow is often seen in patients with tumours.
The Foundation of Alternative and Integrative Medcine describes in an article the difference between anatomic screening methods like X-ray & mammography in comparison with infrared screening (medical thermography). Clearly, medical thermography sees the physiological processes of the body and not the anatomical changes. Therefore it is more used in preventative screening.
Health Canada have issued "cease and desist" orders to clinics offering breast thermography as a claimed cancer diagnostic too because the cameras do not have a medical device licence in Canada.
Scott Gavura of the Science Based Pharmacy blog describes breast thermography as "worse than useless" based on currently available evidence.
- "The accuracy of digital infrared imaging for breast cancer detection in women undergoing breast biopsy.". European Journal of Surgical Oncology. June 2010.
- "Flir imaging cameras". FLIR.
- Thermography, Mammography, and Clinical Examination in Breast Cancer, Radiology vol 122 January 1977, 123-127 doi:10.1148/122.1.123
- Oprah’s buddy Dr. Christiane Northrup and breast thermography: The opportunistic promotion of quackery, David Gorski, 11 Oct 2010. Science Based Medicine
- FDA Safety Communication: Breast Cancer Screening - Thermography is Not an Alternative to Mammography, the U.S. Food and Drug Administration June 2, 2011
- Tsouderos, Trine (25 April 2012). "FDA warns doctor: Stop touting camera as disease screening tool". Chicago Tribune. Retrieved 8 January 2013.
- "What If You Went through a Mastectomy, Only to Discover Your Diagnosis Was False?". Mercola.
- "Flir System AB". FDA.
- Clinics ordered to stop 'useless' breast cancer tests, CBC News, Nov 27 2012
- Thermography: Worse than useless, Scott Gavura, Science Based Pharmacy, 28 Nov 2012