Infrared Thermal Imaging in The Early Detection of Breast Diseases

Infrared Thermal Imaging in The Early Detection of Breast Diseases

   Breast disease is one of the common types of diseases that endanger women's health. With changes in lifestyle, social environment and other factors, the number of breast diseases has gradually increased. In recent years, according to a number of statistical data, the incidence and mortality of breast cancer are increasing year by year, and the age of onset is showing a younger trend. According to data from the International Agency for Research on Cancer, the global incidence and mortality of breast cancer in 2018 still ranked first among female cancers. Early detection and early diagnosis of malignant breast diseases is of great significance, and it is the key to reducing mortality and improving prognosis

   The imaging examination methods for breast diseases are mainly divided into structural imaging and functional imaging. The former mainly includes mammography (MG), magnetic resonance imaging (MRI), ultrasound (ultrasound, US), The latter is mainly infrared thermal imaging technology (infrared thermal imaging, IRTI). Mammography mammography is less sensitive to the detection of dense breast lesions, and may bring a certain risk of radiation exposure. At the same time, the need to compress the breast during the examination will bring discomfort to the patient. The specificity of MRI is relatively low, the price is more expensive, and the examination takes a long time, so it is not used as a routine imaging examination. Ultrasound is currently the most commonly used imaging method for breast examinations in China. It has unique advantages in judging the nature, location, size, number and blood flow of the lesion, but it is extremely dependent on the proficiency and diagnostic experience of the equipment and the operating doctor. Infrared thermal imaging technology is a functional imaging technology that has emerged in recent decades. It has the advantages of non-invasive, non-radiation, fast, and sensitive, and has been used in clinical auxiliary diagnosis of many diseases. It mainly reviews the value of infrared thermal imaging in the early detection and prognosis evaluation of breast diseases.

   Generally speaking, the occurrence of lesions in any part of the body is the first occurrence of local tissue metabolic abnormalities. For malignant masses or inflammatory lesions, due to faster glucose metabolism, increased local blood flow, formation of new blood vessels, and the production of nitric oxide (NO) and estrogen, local heat radiation also changes accordingly. The table shows an increase in temperature. In the past few decades, more and more researches have focused on the use of infrared thermal imaging to obtain the correlation between thermal physiology and skin temperature. Skin surface temperature information has been used to assist in the diagnosis of various diseases of the human body. Including peripheral vascular diseases, breast cancer, diabetic neuropathy, fever screening, pain, skin diseases, gynecological diseases, acupuncture treatment and forensic medicine. Infrared thermal imaging reflects the blood supply and metabolism of tissues and organs of the body by capturing the infrared energy actively radiated by the human body and converting it into a visible temperature image. It is based on the principle that the metabolic activity of the lesion and surrounding tissues is different from that of normal tissues and therefore the temperature is different. Identify the disease. The sensitivity of modern infrared thermal imaging cameras can already detect a temperature difference of 0.025℃. As a safe and reliable functional imaging method to detect breast diseases, infrared thermal imaging is suitable for a wide range of people, including women of all ages, pregnant women, lactating women, and prosthetic implants. It can also be used to monitor disease treatment and understand the condition of the armpits for the enrolled and postoperative patients.

Figure 1. Infrared thermal image of 58-year-old female right breast cancer (subareola area).

   Breast diseases seriously endanger women's physical and mental health, including breast fibroids, breast hyperplasia, mastitis, breast cysts, and breast cancer. Breast masses can be divided into cystic masses and solid masses according to their nature. Because of their different internal components, the metabolic rate of the two is different. Cystic lesions lack blood supply and will not generate additional heat, so they can be distinguished from solid lesions. The study compared the results of infrared thermal imaging with ultrasound and biopsy results of 60 patients with suspected breast disease, and found that the accuracy of infrared thermal imaging in identifying solid masses and cystic masses was 91.89% and 92.30%, respectively. The image can distinguish between solid hypoechoic masses and cystic masses.

   Among solid breast masses, breast cancer is the most harmful. The growth of cancer cells is not controlled. When precancerous cells and cancer cells grow rapidly, in order to meet the demand for nutrients and oxygen, cancer tissues will produce new blood vessels and local metabolism. Speeding up causes the temperature of the corresponding part of the tissue to rise. In 1956, Lawson used infrared thermal imaging for breast cancer detection for the first time and found that the skin temperature of the diseased tissue was higher than that of the normal breast tissue. In 1963, Lawson and Chughtai analyzed that this was due to increased thermogenesis and increased angiogenesis in cancerous tissues. Based on this principle, some scholars have conducted research on the early warning effect of infrared thermal imaging on breast cancer. The study found that about 35% of healthy women with abnormal infrared thermography developed breast cancer within 5 years. It is believed that the role of abnormal infrared thermography in predicting the occurrence of breast cancer is more important than the first-level family history. Abnormal infrared thermography is the future the most important sign of breast cancer risk. Over a period of 10 years, 61,000 women were screened using thermal imaging cameras, and it was found that thermal imaging images provided the earliest information on breast cancer for 60% of cases. There are also reports that infrared thermal imaging can warn breast cancer 8-10 years earlier than mammography. The above research shows that infrared thermal imaging has certain value in predicting the occurrence of breast cancer. Due to the unique ability of infrared thermal imaging for breast vascular imaging, long-term follow-up can obtain very early warning information. Infrared thermal imaging is currently the earliest known indicator to predict breast cancer progression.