CT perfusion, angiogram use for acute ischemic stroke skyrockets

The rates of CT perfusion (CTP) and CT angiogram (CTA) for acute ischemic stroke markedly increased from 2006 to 2010 and both modalities were associated with increased reperfusion therapy use, according to a study published in the April issue of Stroke.

Multimodal CT and MRI have demonstrated promise for increasing patient eligibility for acute reperfusion therapies for ischemic stroke, yet no clinical trials have exclusively investigated CT-based multimodal imaging. “[T]hus, the usefulness of CT-based imaging in making acute stroke treatment decisions is especially lacking,” wrote lead author Achala Vagal, MD, of the University of Cincinnati Neuroscience Institute in Ohio, and colleagues.

The researchers aimed to find nationwide utilization trends of CTA and CTP imaging in acute ischemic stroke, especially in the context of reperfusion therapies, by reviewing the Premier Perspective Database for ischemic stroke-related hospitalizations of adult patients from 2006 to 2010. Vagal and colleagues discovered use of the modalities by examining procedure and billing codes.

The study’s authors found 300,046 ischemic stroke discharge diagnoses over the five-year period. Of these discharges, 79.9 percent of patients were imaged with CT studies. They then discovered that 6.5 percent received CTAs and 1.2 percent received CTP imaging. Of the patients who underwent CTP, 3,606 also received CTAs.

An increased proportion of patients with ischemic strokes received CTAs each year, with 3.8 percent in 2006, 5.6 percent in 2007, 6.5 percent in 2008, 7.5 percent in 2009, and 9.1 percent in 2010.

Additionally, the proportion of acute strokes that were imaged with CTP imaging increased, with 0.05 percent in 2006, 0.05 percent in 2007, 0.9 percent in 2008, 2.2 percent in 2009 and 2.9 percent in 2010.

Reperfusion treatment was more common in those who were imaged with CTA, at 13 percent, and CTP at 17.6 percent, than those with solely CT. Higher rates of recombinant tissue-type plasminogen activator were seen in CTA and CTP than CT alone. Lastly, higher rates of mechanical embolectomy were observed in CTA and CTP than CT by itself.

“CT use tripled and CTP use increased >50-fold from 2006 to 2010, and both were associated with increased reperfusion therapy use,” wrote Vagal and colleagues. “Given limited healthcare resources, the well-publicized risks of radiation, along with limited evidence for clinical benefit of this approach, it becomes imperative that CT-based multimodal imaging selection for acute ischemic strokes be studied in controlled clinical trials.”