Nick Bartz, Imaging Performance Partnerhsip
The rate of utilization of non-invasive diagnostic imaging in Emergency Departments is steadily increasing, according to an article published this month in the Journal of the American College of Radiology. Across all modalities used in the ED, non-invasive diagnostic imaging exams increased from 281 exams per 1000 beneficiaries in 2000 to 450.4 in 2008, an overall increase of 60%. The modality showing the greatest increase was Computed Tomography, whose share of ED imaging doubled from 2000 to 2008.
The study, which examined the Medicare Part B Procedure Summary Master Files for 2000 through 2008, grouped all diagnostic imaging CPT codes into 4 modality categories: (1) radiography (including ﬂuoroscopy); (2) CT, including CT angiography; (3) ultrasound, including body, vascular, and cardiac; and (4) all others (including MRI and nuclear medicine). Radiographic examinations were the most commonly performed, increasing from a rate of 227.3 per 1000 beneficiaries in 2000 to 294.3 in 2008 (29%). CT examinations increased from a rate of 40 exams per 1000 beneficiaries in 2000 to 130.7 in 2008 (227%). Ultrasound examinations increased from a rate of 9.6 per 1000 beneficiaries in 2000 to 18.7 in 2008 (95%). The MRI rate was 0.98 exams per 1000 beneficiaries in 2000, increasing to 3.4 in 2008, however researchers cautioned that the baseline rate in 2000 was so small as to be almost statistically meaningless.
Researchers posited a number of possible reasons for the rapid increase in imaging utilization in the ED. One reason, authors suggested, is that CT has become faster and more accurate, and consequently the indications for its use have expanded. Another reason posited by researchers is that Emergency Departments are experiencing ever increasing caseloads, which is putting ED physicians under increasing pressure to increase patient throughput, forcing them to rely on diagnostic imaging where it may be unnecessary. Of course, another big reason, also recently cited in a survey of Emergency Department physicians is increased pressure for diagnostic certainty among ED physicians in order to avoid malpractice liability.
Though this increase in imaging volume might be somewhat encouraging for radiologists, study authors suggest that as incentives shift with reform, hospitals will put more pressure on radiologists to "work more closely with ED physicians" and to use "more clinical rules and appropriateness criteria to limit imaging growth."