VII.B.31.   One or more ghost-images of a body structure displayed at different depths within an ultrasound image are signs of:

    a.   Shadowing.

    b.   Reverberation.    Correct.

    c.   Refraction.

    d.   Enhancement.

    Discussion:   This is the characteristic appearance of the reverberation artifact.   If there is more than one ghost image they will be separated by the same depths.

    Reference:   Physical Principles of Medical Imaging, 2nd. Edition.   p. 404