Which of the following statements regarding the ICA spectrum is FALSE?

The statement regarding the ICA spectrum that is false is that the waveform suggests severe stenosis greater than 80%. In patients with severe carotid artery stenosis, typically classified as greater than 70% stenosis, the waveform demonstrates significant changes. However, while a very high stenosis level might exhibit certain characteristics, it does not always suggest a uniform "greater than 80%" categorization for all waveforms observed.

A southeastern ICA spectrum often exhibits peak systolic velocities that increase as stenosis severity increases, typically reflecting severe stenosis. However, the distinction lies in how the waveform presents with respect to different severity levels. Volumetric flow rates and specific velocity cut-offs are used to gauge stenosis but note that not all stenosis greater than 80% will manifest in the same way under all conditions.

In addition, statements about significantly elevated peak systolic velocities, filled systolic windows indicating turbulence, and end-diastolic velocities not exceeding 100 cm/sec are all relevant features consistent with ICA pathology associated with significant stenosis. Each of these characteristics confirms how stenotic lesions can present, reflecting hemodynamic changes as observed in vascular sonography.