Mammography Technique Flashcards
What is the aim in positioning?
Maximum anatomical coverage
Optimal contrast
Optimal sharpness m
Minimal dose
Minimal movement
Minimal patient discomfort
What are some feelings and/or challenges that can be associated when being imaged?
Feelings:-
Anxiousness
Embarrassment
Aggression
Not wanting to be there
Painful breasts
Other challenges:-
Mental /physical disabilities
Language difficulties - limited or no english
Maybe hiding something
May have not read information leaflets
Breast implants
Tattoo
Piercing
What are the two standard projections for both men and women?
Medio-Lateral (MLO)
Carnio-Cadual (CC)
What are the patient positioning?
Depends on the area of Interest
Magnified (coned), lateral/ extended views, tomosynthesis
Adapted technique for implant/ post surgical / disabled patients
Adapted technique according to the patient’s shape and size
How is the cranial-caudal view taken?
The cassette is placed under the breast at the level of the inframamary fold
The breast is then pulled until the inframamary fold is taut
Compression is applied and x-ray beam is directed vertically from above
Posterior medial aspect should also be included
How is the medio-lateral oblique view taken?
Best view to image all of the breast tissue and pectoral muscle
The C-arm of the mammographic unit is rotated to 45-degree so that the cassette is parallel to the pectoral muscle
The film holder is kept high up in the axillary fossa and the patient’s arm is abducted to the elbow by 80 degrees
The x-ray beam enters the breast from the medial side - compression is applied to the pectoral major muscles
What are some normal aspects in a normal breast mammography?
The slightly dense areas = the glandular tissue
Some asymmetery in size and breast composition is normal
Dense breasts with generalised distribution of glandular tissue
Very little glandular tissue
Widespread microcalcification but not clustered in an irregular fashion therefore considered ‘normal’
Glandular tissue is absent
What are some common errors when positioning for each?
Medio-Lateral Oblique (MLO)
Skin Folds and tissues superimposition particularly at the IMA and axillary pectoral muscles
Cranio-Caudal (CC)
Skin Folds and tissue superimposition particularly at the medial and lateral mammary angles
What are the anatomical landmarks when imaging a medio-lateral oblique and cranio-caudal?
Medio-lateral oblique
Visualisation of the IMA, pectoralis muscle, retro-glandular fat, nipple in profile
Cranio-caudal
Visualisation of medial (cleavage) and lateral (axillary) mammary angles, pectoralis muscle, retro-glandular fat, nipple in profile
Why is it important for the patients position to the stable?
To prevent movement/blur
Why is the rotation correction important?
To ensure visualisation of marginal (medial, lateral, inferior, and superior) tissue
Why is a relaxed gait and posture important?
To maximise coverage, improve tissue contact, and to optimise compression
Why is height selection important?
To ensure tissue is imaged in profile without rotation superimposition
What is angulation selection important?
To ensure natural anatomical position and optimal profile visualisation from nipple to chest wall
Why is smoothing not the patient’s skin ideal?
To minimise skin folds and tissue superimposition
Why is the position of the glandular tissue over exposure chamber important?
To ensure suitable exposure and contrast of denser glandular tissue
Why is application of adequate compression important?
To separate and immobilise superimposed tissues, improve contrast and limit dose
What are some positioning errors?
Tissue sagging / drooping
Skin smooth - must avoid skin Folds and tissue superimposition particularly at IMA and axillary pectoral muscle
Ensure glandular tissue is positioning centrally over bucky and therefore AEC
Visualisation of pectoralis muscle
Visualisation of appropriate marginal tissue, e.g. medial, lateral, inferior, and superior (for MLO)
Not gaining a stable position
Adequate compression otherwise movement blur
Rotation error - ensure position of feet, hips, and shoulders are appropriate
What are some challenges with compression?
Decreases the thickness of breast thus reducing scattered radiation
Improves the image contrast
What are some points to receive when you do an image appraisal?
Identify the projection
Fatty tissue peripherally
Denser tissue centrally
If microcalcifications, not significant if not clustered
To ensure all anatomy is visualized, including pectoral muscle margin
No rotation
Nipple profile (pectoral to nipple line - PNL)
No skin folds
No blurring
What are some limitations of mammography?
5-10% of breast cancer are mammographically occult - Always listen to patient symptoms
With breast screening comes ‘over diagnosis’
Cultural, generational, socio-economic
HRT/Hormones - can increase patient discomfort/dose
- can limit mammographic sensitivity/contrast
Patient compliance & co-opration
What are some things that happenes at a breast clinic?
Clinical assessments
Ultrasound
Biopsy - ultrasound guided or stereotactic biopsy
What is ultrasound guided biopsy?
Focal mass or other lesion of unknown nature - palpable or non-palpable
Architectural distortion
Cyst aspiration
? Microcalcification
What is stereotatic core biopsy?
Most commonly performed on microcalcifications present in the breast that an ultrasound can’t detect
