Rising costs of medical imaging spur debate.

M edicare spending on medical imaging services reached $14 billion in 2006, more than double the 2000 spending, according to a report from the Government Accountability Office (GAO) released in June. The GAO also found that the proportion of spending on imaging services performed in physician offices rose from 58% to 64%, whereas the proportion of spending on imaging performed in hospitals dropped from 35% to 25% over that same period. This shift from hospitals to outpatient settings, along with a substantial variation in spending per benefi ciary in different regions of the country, has raised concerns that not all of the imaging being done is medically necessary, according to the report. The GAO recommended that the Centers for Medicare and Medicaid Services (CMS) manage the rising costs by implementing practices used by private health plans, such as requiring prior authorization. Although many agree that spending on medical imaging has indeed risen dramatically and may need to be constrained, there are still different ideas about the best way to proceed. At the heart of the debate is the diffi culty of pinning down the true benefi ts of imaging — its effect on diagnosis, treatment, and length of hospital stay, for example. Moreover, the rapidly advancing technology and ever-widening scope of diseases and conditions for which imaging is used are making it diffi cult to rigorously and thoroughly analyze the medical benefi ts, harms, and cost-effectiveness of imaging.