The Effect of Contact Pressure on Ex-vivo Measurements of the Conductivity of Liver

Ištuk, Niko; Benchakroun, Hamza; Elahi, Muhammad Adnan; O’Halloran, Martin

doi:10.23919/eucap53622.2022.9769625

Cited by 2 publications

(4 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, there is no clear understanding regarding the effect of the contact force of the probe on the tissue on the resulting measurements [ 5 , 29 , 30 ]. Furthermore, the mechanisms behind the change in conductivity due to contact force are not fully understood, and the effect of contact force on tissue conductivity varies between tissue types [ 5 , 30 , 31 , 32 ].…”

Section: Introductionmentioning

confidence: 99%

“…In addition to quantitative reporting of the contact force, the effect of the contact force on the tissue conductivity may vary depending on the tissue type. Of the studies which have investigated the effect of contact force on the measured conductivity of tissue, different trends have been reported, from increasing conductivity with increased force to decreasing conductivity with increased force [ 5 , 30 , 31 , 32 ]. These studies investigating tissue conductivity change due to contact force do not appear in the online databases at the time of submission.…”

Section: Introductionmentioning

confidence: 99%

“…However, for some tissues, such as lung, the conductivity is increased as more contact force is applied, which is likely due to the air being pushed away from the alveoli [ 32 ]. Furthermore, different behavior is seen in liver tissue, where the contact force applied by the probe has little effect on the conductivity [ 31 ]. A change of +0.8% per 1 N of applied force (per 6.25 kPa of applied pressure) is observed in the liver [ 31 ].…”

Section: Introductionmentioning

confidence: 99%

“…Furthermore, different behavior is seen in liver tissue, where the contact force applied by the probe has little effect on the conductivity [ 31 ]. A change of +0.8% per 1 N of applied force (per 6.25 kPa of applied pressure) is observed in the liver [ 31 ]. Table 2 shows the different behavior of the various tissues under monotonically increasing contact force.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Probe Contact Force Monitoring during Conductivity Measurements of the Left Atrial Appendage to Support the Design of Novel Diagnostic and Therapeutic Procedures

Benchakroun

Ištuk

Dunne

et al. 2022

Sensors

Self Cite

View full text Add to dashboard Cite

The electrical properties of many biological tissues are freely available from the INRC and the IT’IS databases. However, particularly in lower frequency ranges, few studies have investigated the optimal measurement protocol or the key confounders that need to be controlled, monitored, and reported. However, preliminary work suggests that the contact force of the measurement probe on the tissue sample can affect the measurements. The aim of this paper is to investigate the conductivity change due to the probe contact force in detail. Twenty ex vivo bovine heart samples are used, and conductivity measurements are taken in the Left Atrial Appendage, a common target for medical device developments. The conductivity measurements reported in this work (between 0.14 S/m and 0.24 S/m) align with the literature. The average conductivity is observed to change by −21% as the contact force increases from 2 N to 10 N. In contrast, in conditions where the fluid concentration in the measurement area is expected to be lower, very small changes are observed (less than 2.5%). These results suggest that the LAA conductivity is affected by the contact force due to the fluid concentration in the tissue. This work suggests that contact force should be controlled for in all future experiments.

show abstract