Proper mammographic positioning is essential to detecting breast cancer, yet numerous studies have shown that poor positioning is a common culprit when quality is suboptimal. As technologists have primary responsibility for this aspect of the screening process, it should follow that techs who get extra training in positioning will acquire high-quality images more consistently than those who don’t.
That’s indeed the case, according to a study conducted in Canada and published online Aug. 24 in Academic Radiology.
Marie-Hélène Guertin, MSc, of the Institut national de santé publique du Québec and colleagues had an expert radiologist evaluate positioning quality of a random sample of 1,278 mammograms drawn from 394,190 screening exams performed from 2004 to 2005 in the Breast Cancer Screening Program of Quebec.
Next they mailed a questionnaire to 254 randomly selected technologists. Its questions covered experience, training and practice.
The team used multivariable Poisson regression models to assess the association of technologists’ characteristics with higher positioning quality.
The survey response was a robust 86.6 percent (220 responses).
Responding technologists performed 89.2 percent of available sampled mammograms (1,088 of 1,220), of which 45.9 percent were of higher positioning quality, the authors report.
Their key findings:
- Technologists who received more than 15 hours of additional hands-on training in positioning—on top of the seven hours of formal training the province of Quebec mandates for positioning—performed mammograms with better positioning than technologists with no additional training.
- Techs who were involved in providing at least 15 hours of continuing medical education achieved higher positioning quality than those who provided less than 15 hours of continuing medical education.
- Techs who were involved in film development had better positioning quality than those who were not.
The researchers also found that the proportion of mammography experience techs had in screening vs. diagnostic settings was associated with positioning quality, although this association was less clear.
In their discussion, Guertin and colleagues note that mammography technologists cannot reasonably be expected to perform screening exams that always and everywhere satisfy the positioning quality criteria established by the American College of Radiology and the Canadian Association of Radiologists.
“This is due in part to characteristics of women, which can sometimes prevent some criteria, such as adequate presentation of the pectoral muscle, to be fulfilled,” they write. “Technologists with excellent positioning skills might, however, better adapt their technique in challenging situations such as when the woman is obese, is stressed, has a prominent sternum or is in a wheelchair. In these situations, a screening examination, although not satisfying all positioning requirements according to the ACR/CAR criteria, could still allow a clear visualization of most breast tissue.”
In any case, extra hands-on training in positioning “appears to offer one of the best approaches to improve mammography positioning quality,” they conclude, “as many technologists have not had such additional training.”