Editor—Toole's voice is important in the controversial debate on carotid surgery.1 However, in determining a cut-off point for selecting patients for endarterectomy, the different methods of measurement (local versus distal degree of stenosis) used by European and American surgery trials must be considered.2
A cut-off point of 60% stenosis refers to the asymptomatic carotid artery stenosis study (ACAS) and uses the American method of stenosis measurement3; that degree of stenosis corresponds to a 75% stenosis according to European criteria.2 Therefore, to define a cut-off point of 60% stenosis in a European journal is misleading.
I agree with Toole that other indicators for selecting patients for carotid surgery should be considered; however, apart from the degree of stenosis, there are no evidence based criteria that allow medical or surgical treatment to be decided. So the degree of stenosis remains the main criterion; measurement should be performed by means of Doppler and duplex ultrasound evaluation.4
Competing interests: None declared.
References
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