Fibrous Cap Thickness and Rupture in Carotid Atheromata: Still Hunting in the Dark?

To the Editor:Redgrave et al1 are to be congratulated for their superb and cumbersome work. We had been waiting for a large well-designed histopathologic study focusing exclusively on the critical cap thickness of carotid atheromata, and we are grateful for this important contribution. Hitherto, data extrapolation from coronary pathology to the carotids had left to vascular neurologists the bitter taste of hunting in the dark. We had published 3 years ago the first in vivo study of cap thickness measurement in carotid atheromata2 and had proposed a threshold of 650 μm for the mean cap thickness for the differentiation between symptomatic and asymptomatic plaques. The currently proposed threshold of 500 μm1 for representative cap thickness, in my view, lies in full accordance with our results, if one considers the fundamental methodological differences between …