PGMI evaluation system

PGMI (Perfect, Good, Moderate, Inadequate) is a method of evaluation of clinical image quality in mammography developed by the United Kingdom Mammography Trainers Group with the support of the Royal College of Radiographers, aimed to ensure the maintenance of a high standard of mammography in Breast Screening and to facilitate a method of external audit.

  1. all breast tissue imaged (fat tissue visualised posterior to glandular tissue
  2. correct image identification clearly shown
    • date of examination
    • client identification—name and (number and/or date of birth)
    • side markers
    • positional markers
    • radiographer identification
  3. correct exposure according to workplace requirements
  4. good compression
  5. absence of movement
  6. correct processing
  7. absence of artefacts
  8. no skin folds
  9. symmetrical images
Specific positioning criteria for CC view:
  • 1. all breast tissue imaged
    • medial border well demonstrated
    • nipple in profile (retro-areolar tissue well separated)
    • nipple in midline of imaged breast
    • posterior nipple line (PNL) within 1cm of PNL on MLO view
Specific positioning criteria for MLO view:
  • 1. all breast tissue imaged:
    • pectoral muscle shadow to nipple level
    • full width of pectoral muscle
    • nipple in profile (retro-areolar tissue well separated)
    • infra-mammary fold well demonstrated
    • PNL within 1cm of PNL on CC view
P = Perfect images
  • CC images meet criteria for image assessment 1−9
G = Good images
  • 1. All breast tissue imaged (axillary portion of breast not to be included at expense of medial portion)
    • all postero-medial tissue visualised
    • nipple in profile
    • nipple in midline of imaged breast
  • 2 - 6. CC images meet criteria for image assessment 2−6 inclusive for categorisation as G
  • 7 - 9. CC images displaying minor degrees of variation in criteria for imaging assessment 7, 8 and 9 will be accepted for categorisation as G
M = Moderate images (Acceptable for diagnostic purposes)
  1. Most breast tissue imaged 
    • nipple not in profile but clearly distinguishable from retro-areolar tissue
    • nipple not in midline (significant bias)
  2. Correct(ed) image identification
  3. Correct exposure
  4. Adequate compression
  5. Absence of movement
  6. Correct processing
  7. Artefacts which do not obscure the image
  8. Skin folds which do not obscure the breast tissue
  9. Asymmetrical images
I = Inadequate images 
  1. Significant part of the breast not imaged
  2. Incomplete or incorrect identification
  3. Incorrect exposure
  4. Inadequate compression hindering diagnosis
  5. Blurred image
  6. Incorrect processing
  7. Overlying artefacts
  8. Skin folds obscuring the image
P = Perfect images
  • MLO images meet criteria for image assessment 1−9
G = Good images
  • 1. All breast tissue imaged
    • pectoral muscle well demonstrated
    • nipple in profile
    • infra-mammary fold (IMF) well demonstrated
  • 2 - 6. MLO images meet criteria for image assessment 2−6 inclusive for categorisation as G
  • 7 - 9. MLO images displaying minor degrees of variation in criteria for 
  • imaging assessment 7, 8 and 9 will be accepted for categorisation as G
M = Moderate images (Acceptable for diagnostic purposes)
  1. Most breast tissue imaged.
    • Pectoral muscle not to nipple level but posterior breast tissue adequately shown
    • nipple not in profile but clearly distinguishable from retro-areolar tissue 
    • IMF not clearly demonstrated but breast tissue adequately shown
  2. Correct(ed) image identification
  3. Correct exposure
  4. Adequate compression
  5. Absence of movement
  6. Correct processing
  7. Artefacts which do not obscure the image
  8. Skin folds which do not obscure the breast tissue
  9. Asymmetrical images
I = Inadequate images 
  1. Significant part of the breast not imaged
  2. Incomplete or incorrect identification
  3. Incorrect exposure
  4. Inadequate compression hindering diagnosis
  5. Blurred image
  6. Incorrect processing
  7. Overlying artefacts
  8. Skin folds obscuring the image

(Image classification in relation to PGMI system to maximize high quality of images and minimise technical repeats)

A minimum of 50% of an audit of 50 randomly selected cases should be graded in: 
  • P or G categories (75% desirable) or
  • P or G or M categories (97% desirable)
Repeat rate:

<3% of consecutive images to be classified "Inadequate"

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Article information

rID: 25772
System: Breast
Synonyms or Alternate Spellings:

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