Simple Test Of Transducer Arrays By Imaging Of Ultrasound Emission Into Air

Abstract

Abstract: A simple test method, feasible for remote or online testing of multi-element ultrasound transducer arrays, is presented. The test requires only a conventional ultrasonic B-mode image visualizing the transducer under investigation emitting into air. In preparation of the test a gray value profile is computed from the image data. Defective trans-ducer elements cause deviations in the profile, which are analyzed by means of a statistical procedure. The perform-ance of the test was investigated using an ultrasonic imaging system (SonixTOUCH, Ultrasonix Medical Corporation, Richmond, Canada) in research mode and masking single elements or element groups to simulate damaged piezoelec-tric elements. The test method allows to detect 2 adjacent defective elements out of a total of 128 transducer elements. Keywords: ultrasound diagnostic, multi-element trans-ducer arrays, quality assessment, statistic evaluation Introduction The quality and reliability of a diagnosis drawn on the basis of a ultrasonic investigation depends to a great ex-tend on the technical quality of the imaging system. Over the last years a number of test methods has been estab-lished which are able to detect different failure types at specific points in the signal chain and at different levels [1]. The ultrasound probe - a high sensitive, mechatronic device - is considered to be the most failure-prone part of the system [2]. Consequently a simple, user independent and reliable test of the transducer elements is a prerequi-site for a broader acceptance of technical quality assur-ance (TQA) in the user community. The analysis of B-mode images acquired when the ultrasound waves are emitted into air could provide such a test modality.