CT Angiogram Helps Monitor Cerebral Aneurysm Growth

Monitoring cerebral aneurysms with CT angiogram permits physicians to watch for lesion growth regardless of the original size, allowing for quick intervention if necessary, according to a study published online in the journal Radiology.

Current guidelines suggest that known aneurysms that are smaller than seven millimeters do not need to be monitored with imaging because they are considered to be at low risk for rupturing. To assess if this recommendation was valid, researchers from the David Geffen School of Medicine at the University of California, Los Angeles, sought to identify the risk factors for cerebral aneurysm ruptures.

The researchers, led by J. Pablo Villablanca, MD, chief of diagnostic neuroradiology, studied 165 asymptomatic patients (132 women, 33 men) who had been discovered to have cerebral aneurysms either incidentally or during a baseline study. A total of 258 aneurysms were identified. The patients underwent CT angiography every six or 12 months for a mean of 2.24 years.

The images showed growth in 46 of all intracranial aneurysms in 38 patients. Three of the 39 growing saccular aneurysms ruptured, and of those, all were smaller than seven millimeters in size at study entry.

Compared to the aneurysms that stayed the same size, the 46 growing aneurysms were associated with a 12-fold higher risk of rupture. The researchers calculated the risk of rupture for growing aneurysms at 2.4 percent per patient-year versus 0.2 percent for aneurysms that did not grow.

“The positive association between aneurysm growth, aneurysm size, and cigarette smoking suggests that the combination of these factors are associated with an increased risk of rupture and may influence the need for therapeutic intervention,” Villablanca said in a release.