Answer:
Inability to clearly demonstrate small cystic structures
Step-by-step explanation:
Ultrasonic imaging is an integral and routine procedure in many medical applications. An increased awareness of the need for quality assurance in this field has led to numerous tests being proposed. Due to the complexity of the problem, the tests directly measuring the important parameters of resolution and contrast of low-echoic structures are not unified, often more qualitative than quantitative, and are performed at large periodic intervals. Uniform sensitivity of an array transducer is a necessary but insufficient requirement for imaging quality of an ultrasound probe. Good probe uniformity should in no way be confused with meaning the ultrasound probe is working as it should.
Results :
The 3-D view shows alternating orthogonal profiles. The lateral profile is determined at a single lateral position. To allow extrapolation of the result, scanner uniformity is required.
Uniformity will not work with phased arrays. As they need increased phase shifts for larger angles, side lobe generation increases at those angles, requiring additional measurements to check the respective quality reduction. For all other cases, a single 3D acquisition provides the complete information. The profiles can be plotted in 2D or 3D views.
As the beam profile changes only gradually between the single filaments, it is possible to interpolate the values between two successive points. Creating a grey-scale image using these interpolations provides an improved visualisation of the side lobes .