Early diagnosis of atherosclerosis is essential as many of the risk factors are life-style dependent. We suggest a new method to measure minute roughness of the size of micrometers of the arterial wall. The method was evaluated using three silicone phantoms sized 13 μm, 23 μm and 33 μm, respectively. The mean of the measured heights of the phantoms were 8.1 μm (SD 0.0), 23.3 μm (SD 0.2) and 29.6 μm (SD 0.1) in the forward direction, and 7.7 μm (SD 0.0), 21.9 μm (SD 0.2) and 27.3 μm (SD 3.6) in the backward direction, respectively. The phantom study shows very promising result and encourages to further evaluation and in vivo investigations.