• Artery
• Brain
• Atherosclerosis
• Stroke
• Intervention

“You say yes and I say no

You say stop and I say go, go, go

Oh no.”

— Beatles, 1967

Hirsch and colleagues¹ see page 27 and Cloft and colleagues² have used different models to estimate the current case volume of intra-arterial stroke therapy and extrapolate its potential future demand. Secondarily, each attempts to draw conclusions regarding current work and future work force demands based on their estimates.

In order to generate their estimates, Hirsch and colleagues¹ performed a literature search to construct a range of patients receiving intravenous therapy. Additionally, they used data from Concentric Medical and two published references to determine the total number of acute stroke cases in which the Merci retrieval device was utilized and the range of percentage use of the retrieval device in order to calculate a range of current intra-arterial therapy volume. Furthermore, they utilized case volume numbers from two busy stroke centers, which historically have aggressively pursued intra-arterial therapy, to extrapolate the potential volume if 100–500 centers nationally treated similar percentages of strokes with intra-arterial techniques.

Cloft and colleagues² started with the current American Heart Association estimate of the incidence of stroke in the USA. They refine this number based on literature data to obtain an incidence of ischemic stroke. In order to calculate the number of patients yearly with severe (National Institute of Health Stroke Score > 10) ischemic disease which they used as a maximum pool of patients who might be eligible …