The number of mammography images in Central Health that have been identified as needing further review has risen to nine.

The health authority was the first to report issues with mammography viewing stations, some of which were found to be operating at three megapixels, instead of the standard five megapixels. In total, 3,000 images have been affected.

Subsequent reviews by the other three health authorities discovered an additional 13,000 images that had been viewed on substandard equipment.

To date, 2,564 of the 3,000 images have been read, with nine follow-ups needed.

Central Health says the number of discrepancies or differing opinions remains low, suggesting that the risk to patients is low.

The review of the remaining 523 images will be completed by the end of the month.