[Experimental studies in transurethral, intravesicular ultrasonographic research]

The investigations were performed via a 7.5 MHz transurethral rotating ultrasonic probe. The axial and lateral resolution was determined. The experiments for the determination of the thickness of the bladder wall and for the discrimination between the different types of tissue were carried out by means of pig's bladders and biological specimen. A certain and reproducible discrimination of the different tissue layers and an exact determination of the thickness of the bladder wall were not possible due to the missing single echoes of the boundary interfaces and to the dependence of ultrasonic image structures on the selected amplification. Additionally, the speckled structures of the ultrasonic images have a magnitude of millimetres and render the discrimination very difficult between tumour tissue and bladder wall tissue. We would require signal processing by computer to obtain an exact resolution of the signal information.