Mammography

Mammography is a dedicated radiographic technique for imaging the breast.

Types of mammography

In general terms, there are two types of mammography: screening and diagnostic.

Mammography differs significantly in many respects from the rest of diagnostic imaging.

Screening mammography 

This imaging procedureIn general terms, screening mammography is doneperformed on asymptomatic females in an effort to identify and categorise breast pathology. In general terms. screening mammography is done towomen to identify malignant breast pathology at an early, potentially curable stage. Regardless of all the hype in the litertureliterature and the confusing statistics in lay publications, the earlier breast cancer is picked up, all other factors being equal, the better the survival rate.  Period. Screening mammography is done on clients, not patients.

Diagnostic mammography

Imaging done on a symptomatic patient, or in follow up ofto work-up an abnormality found on screening mammography. The object is to use imaging to typify pathology and arrive at a diagnosis. This is important because diagnoses have outcomes and survival rates. firFor instance, a diagnosis of a simple breats cystbreast cyst has few implications and does not affect the patient's life expectancy. In contrast, a diagnosis of breast cancer has significant implications for the patient and her life expectancy.

Differences between the screening and diagnostic environments

Screening studies are well performed by trained sympathetic staff in environments that are not necessarily located in hospitals. Screening centres function very well as stand alone locations without a physician on site. The studies are read by breast imagers inradiologists in an isolated environment where there are no distractions or interruptions. In contrast to the rest of radiology, these studies are read in batches and in volumes. Where screening studies are read in environments where interruptions, phones and distractions are present, mistakes happen.

Diagnostic studies are performed with a radiologist on site and involved with every step of the imaging procedure.  Interruptions are part of the process and are an essential interaction.

Why is a diagnosis of breast cancer significant?

The diagnosis of breast cancer is a significant for many obvious and notperhaps less obvious reasons. The diagnosis not only affects the patient, but affects her direct family and the direct communitythose around the patient and her kids; her sisterfemale relatives,  thethe mothers at school and the ladies at her church, for insatnceinstance. The disease has a sinister reputation because of the debiltating cosmetic results traditionally associated with surgery and the invariably bad outcome for the patient traditionally associated with the disease.

Why is mammography important?

Until a cure for the disease is found, this is the best tool we have to find breast cancers early i.e. before they are palpable. The result of this is a potential cure for the patient and cosmetically acceoatbleacceptable surgery, if required. In genral terms, the earlier a cancer is found, the better the outcome. We luckily no loberlonger live in a world of Halsted mastectomies.

Why does a breast imager read mammograms?

For some strange reason, not all radiologists are "wired" to read breast imaging.  TheThe reason for this is unclear. This has nothing to do with capability or intelligence or competency in other fields of imaging. Mammogram readers must have statistically proven, reproducible proficiency to allow them to qualify to read the images and to objectively and independently confirm their proficiency. This is important because of the emotive and potentially disturbing consequences of a significant finding on a mammogram. Unnecessary recalls cost money, do not add value and upset the patient and her phsyician.

Why all the adverse publicity for mammography?

It has become politically correct to question the value of mammography. Most of the adverse publicity has a single source out of the The  Cochrane CollaberationCochrane Collaboration and from one author. The emotion around the disease and its appeal in the lay lterture then fuels the publicity which detracts from the scientifically proven value of early diagnosis, improved survival and cosmetically acceptable treatment. A review of the ongoing debate in this regard is out of the scope of this website so is not supplied. Suffice to say that in many respects this is an unfortunate debate driven by people who are not breast imagers and it detracts time, money, effort  and attention from the real issue, finding a cure. This debate has many features in common with the infamous debate surrounding autism and MMR vaccination.

Criteria for image quality assessment

• all breast glandular tissue imaged
• image annotation
  • date
  • patient ID (name and URN or DOB)
  • side markers
  • radiographer ID
  • cassette ID (ideally)
• correct exposure - can "bright light" skin and nipple
• no movement artifact
• no skin folds
• symmetrical images

Adequate craniocaudal views

• all glandular tissue identified
• nipple in profile
• nipple in midline of image
• length of posterior nipple line (PNL) within one 1cm in size c.f PNL on MLO
• images symmetric

Adequate medio-lateral oblique views

• pectoral shadow seen down to level of nipple or lower
• inframammary fold well seen
• nipple in profile
• length of posterior nipple line (PNL) within one 1cm in size c.f PNL on CC
• images symmetric