3D reconstruction of handheld data by SAFT and the influence of measurement inaccuracies

In this paper, we investigate the influence of measurement inaccuracies of assisted handheld ultrasound measurements on reconstructions with the Synthetic Aperture Focusing Technique (SAFT). The assistance system tracks the position of the handheld transducer with a camera. The accuracy of such a tracking is inferior to the accuracy of positioning systems in automated measurement setups. Further, due to the manual transducer movement, the coupling of the transducer can vary, which is an additional error source. We carry out two simulation studies that investigate each of the error sources separately. We evaluate the simulations by computing the (Generalized) Contrast to Noise Ratio on C-images of the SAFT reconstruction. The results show that the SAFT reconstruction is sensitive even to small model mismatches due to tracking or coupling errors, demonstrating that monitoring of these effects is required for reliable reconstruction. An exemplary SAFT reconstruction of handheld measurement data is shown.