Novel Lead Configurations for Robust Bio-Impedance Acquisition

This paper describes a diagnostic medical instrument that has undergone a multi-centre 6500-patient clinical trial to evaluate its effectiveness as a replacement for screening X-Ray mammography. The device uses a single bipolar current source multiplexed to two 32-element electrode arrays. The multiplexer allows three novel lead configurations to be measured in addition to the common tetrapolar configuration used in many impedance-acquisition systems. These additional configurations allow pre-testing of electrode contacts, post-testing assessment of measurement fidelity and correction for the effect of shunt-capacitive pathways. The results of the clinical trial show that the device can be operated reliably by individuals with only one day of specialized training and that the device can distinguish between normal and diseased breasts.