Mammography

 

Mammography (Mastography) is a specialised medical imaging that uses a low-dose x-ray (30 kVp) system to see inside the breast.  A mammography examination, called a mammogram aims to detect the early stages of breast cancer by detecting characteristic masses or microcalcifications.  An x-ray (radiograph) is a non-invasive procedure that helps in the diagnosis and treatment of medical conditions.  Therefore, imaging with x-rays enables a picture to be taken of the human body by using a dose of ionising radiation.  Wilhelm Conrad Roentgen discovered x-rays in 1895 by working with a cathode-ray tube: he observed a fluorescent glow of crystals near the tube.  Since then x-rays have become central to medical imaging, especially with advances in mammography which include breast tomosynthesis, digital mammography and computer-aided detection. Other imaging modalities which assist mastography include ultrasound, ductography, positron emission mammography (PEM) and magnetic resonance imaging (MRI).  In addition to this ductography is used to evaluate patients exhibiting areola and nipple problems.  However, mammography has historically been the gold standard for breast cancer screening tool for over four decades.  Alternative screening tools are becoming more prevalent; especially digital mammography, which allows images of the breasts to be depicted in a digital format compared to traditional mammography which is on film.  Thermography is a non-invasive procedure which does not emit radiation and is based on infrared technology to detect inflammation in breast tissue.  Also, thermography can be performed during pregnancy as dense breast tissue is a limitation with mastography.  Another non-radioactive technique used to assist breast screening programmes for pregnant women is ultrasound. This non-invasive diagnostic tool has the ability to detect breast cancer and microcalcifications at rates comparable to mammography.  Furthermore, the cumulative effect of routine mammography screening may increase the risk of radiation-induced breast cancer.  In addition, women who are carriers of the BRCA gene may be at higher risk from the effects of mammography radiation.  Studies have shown that the effect of diagnostic chest x-rays on breast cancer found that medical radiation exposure increases the risk of developing breast cancer.