An ultrasound waveguide that is attachable to an ultrasound probe so as to identify a target area on a target object. The ultrasound waveguide has an ultrasound transducer coupling signal to be transmitted through a guide means. The ultrasound waveguide also has a positioning means for positioning the guide means in relation to the target area on the target object. The guide means is provided with a channel that provides a discontinuity within the guide means that causes a discontinuity in the ultrasound signal emitted by the probe. The presence of this discontinuity allow for proper alignment of the ultrasound waveguide with the target object.