Central Health says mammograms were read using deficient work stations for nearly 3 years

Central Health is reviewing the mammogram results of about 3,000 patients after discovering some employees had been using inadequate monitors to read diagnostic images, the health authority admitted Wednesday.

Central Health CEO Andrée Robichaud said the health authority learned about a week ago that some of its work stations are not up to technical standards. She said the problem is with the monitors used to view the mammograms, not with the testing equipment.

"Our sample review suggests the occurrence presents a low risk to patients," Robichaud said during a virtual media availability.

Robichaud said the health authority has hired an external radiologist, Dr. Nancy Wadden, to review all images read on three megapixel monitors from Nov. 1, 2019, to Aug 19 of this year. She said the review will be completed in September.

Robichaud said Wadden has completed a sample review of mammogram results for 329 patients and found two "potential discrepancies or deferring interpretations."

She said an additional 132 patients' diagnostic images had been reviewed by Tuesday evening, and another error was found. The mammograms were read in Gander and Grand Falls-Windsor but include anyone from the region.

Dr. Mark Spurrell, acting chief of staff for Central Health, said three work stations used for viewing mammograms did not meet Health Canada's safety code or the Canadian Association of Radiologists' guidelines. 

According to Spurrell, Health Canada and the Canadian Association of Radiologists require mammograms to be viewed on work stations that include two monitors, both of which with a screen resolution of at least five megapixels.

Spurrell said Central Health has six work stations that have five-megapixel monitors, but the health authority also has work stations with three-megapixel monitors, which don't meet the standards for viewing and interpreting mammograms.

He said Central Health has started an internal review to examine mammography viewing practices and prevent future incidents. 

Scheduled mammograms are still proceeding in Central Health, and Spurrell said those images will be read using the correct viewing stations. 

Problem undiscovered for 3 years

Robichaud said Central Health does audit its equipment and does maintain "certain standards," but the health authority hasn't determined why the problem went undiscovered for nearly three years.

"Our main concern right now is around disclosure," she said.

Robichaud said it also isn't yet known if staff viewed mammograms using three-megapixel monitors because they were working from home.

"We need to look at process and we need to look at our professionals," she said.

Robichaud said she doesn't know when the review will be completed.

Health Minister Tom Osborne said Wednesday said he learned about the errors a week ago.

"The first priority, the most important priority here, is rereading images," he said.

All 4 health authorities reviewing results

Central Health announced Monday that it was reviewing mammography results for possible "discrepancies." On Tuesday, the province's other three health authorities — Eastern Health, Western Health and Labrador-Grenfell Health — all announced preliminary reviews of its own diagnostic imaging.

From 1997 to 2005, Eastern Health and its precursor gave nearly 400 breast cancer patients incorrect hormone receptor test results. In 2009, a judicial inquiry found that the regional health authority failed patients with shoddy laboratory work and "practically non-existent" quality controls.

Osborne was also health minister during the judicial inquiry, known as the Cameron Inquiry, and served as witness. He said Central Health is being more transparent than Eastern Health was at the time.

After the news conference, Progressive Conservative health critic Paul Dinn noted Wednesday one of the inquirys recommendations from the judicial inquiry was to ensure diagnostic systems were up to par.

"You go in and you have such an important test done, and you're waiting on the diagnostics, and you think you're well, and you think you're fine, and now you hear that may not be the case. I can't imagine," he said.

Central Health CEO learned of issue last week

Dr. Angela Pickles, clinical chief of medical imaging for Eastern Health, noted mammograms are used to screen for breast cancer, rather than for patients who have already been diagnosed. The proportion of patients who received faulty hormone receptor test results from 1997 to 2005 was far higher than the number of errors discovered so far in Central Health mammogram results.

Pickles said five-megapixel viewing stations became standard in 2018. She said the human eye struggles to differentiate between five-megapixel and three-megapixel monitors.

"This is a constantly evolving process as things change [with] different technological advances," she said.

Pickles, who is advising Central Health, said it isn't clear if the three discrepancies found so far are a direct result of the substandard viewing monitors, or because of differences in interpretation.

She said the health authority is reviewing tests only as far back as Nov. 1, 2019, because it doesn't have data showing which monitors were used to view mammogram results before that date.

Robichaud said a Central Health employee flagged that not all work stations were using the five-megapixel monitors. She said she learned about the issue a week ago, and the regional health authority then began auditing mammogram results.

Pickles said Central Health is notifying the three patients who had incorrect mammogram results. She said patients with discrepancies in their mammograms will likely receive further testing, and it isn't clear if some patients will receive a different diagnosis.

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