PACS results in more incidental cervical spine MR findings By Erik L. Ridley AuntMinnie staff writer November 29, 2006
CHICAGO - Adoption of PACS may lead to an increase in incidental findings and follow-up imaging exams, according to researchers from Thomas Jefferson University (TJU) Hospital in Philadelphia.
"There's a vast array of incidental findings seen on routine cervical spine MRI examinations," said Dr. Ketan Naran. "PACS implementation does appear to be associated with an increase in reported incidental findings and also an increase in recommended follow-up studies."
Naran presented the research Wednesday at the 2006 RSNA meeting in Chicago.
Prior to PACS, hard-copy studies were cropped to a region of interest and had limited or no images from a localizer sequence, Naran said. With PACS, however, soft-copy studies usually contain uncropped images and include localizer sequences.
"This helps result in a larger field-of-view, and also results in the imaging of areas outside of the anatomical area of interest, in this case the cervical spine," Naran said. "This increases the potential for incidental findings not related to the cervical spine."
Following up on previous TJU research that found an increase in incidental findings and follow-up exams in lumbar spine MRI studies from PACS, the TJU researchers studied a total of 3,000 cervical MRI spine reports, consisting of 500 consecutive full cervical spine MRI reports in each of six different yearlong periods. 1994 and 1996 were considered pre-PACS periods, while 1998 was a PACS transition year at the institution. 2000, 2002, and 2004 were post-PACS implementation years for the purpose of the study.
The researchers documented the number of incidental findings, anatomic structures involved, and the number of imaging follow-up studies recommended. The patient population included 1,799 females and 1,201 males, with a mean age of 46.6 years.
A total of 290 findings (8.7%) were found among 260 patients. The number of incidental findings increased from 29 (1994) and 17 (1996) in the pre-PACS years to 50 (2000), 73 (2002), and 83 (2004) in the post-PACS implementation years, according to Naran.
A significant increase was seen in thyroid and esophageal lesions, as well as lung masses, he said. Incidental findings included 68 thyroid, seven esophageal, 15 pulmonary, 38 nasopharyngeal, 74 posterior fossa, and 27 neck soft-tissue abnormalities. The 204% increase in incidental findings from the pre-PACS to post-PACS years was statistically significant (p < 0.0001), Naran said.
The number of follow-up imaging studies climbed from six (1994) and six (1996) to 13 (2000), 13 (2002), and 27 (2004). The 192% increase between pre- and post-PACS years was also statistically significant (p < 0.0001). The increase in follow-up studies led to a rise in costs of 94%, he said.
While these increases in imaging studies result in initial higher cost to the healthcare system, these results may improve patient outcomes from greater incidental discoveries of significant occult pathology, Naran said.
"For example, the discovery of occult malignancies may result in early treatment and improving on the morbidity and mortality of patients," he said.