Dataset Information

Detecting carotid stenosis from skin vibrations using Laser Doppler Vibrometry - An in vitro proof-of-concept.

ABSTRACT: Early detection of asymptomatic carotid stenosis may help identifying individuals at risk of stroke. We explore a new method based on laser Doppler vibrometry (LDV) which could allow the non-contact detection of stenosis from neck skin vibrations due to stenosis-induced flow disturbances. Experimental fluid dynamical tests were performed with water on a severely stenosed patient-specific carotid bifurcation model. Measurements were taken under various physiological flow regimes both in a compliant and stiff-walled version of the model, at 1 to 4 diameters downstream from the stenosis. An inter-arterial pressure catheter was positioned as reference. Increasing flow led to corresponding increase in power spectral density (PSD) of pressure and LDV recordings in the 0-500 Hz range. The stiff model lead to higher PSD. PSD of the LDV signal was less dependent on the downstream measurement location than pressure. The strength of the association between PSD and flow level, model material and measuring location was highest in the 0-50 Hz range, however useful information was found up to 200 Hz. This proof-of-concept suggests that LDV has the potential to detect stenosis-induced disturbed flow. Further computational and clinical validation studies are ongoing to assess the sensitivity and specificity of the technique for clinical screening.

SUBMITTER: Mancini V

PROVIDER: S-EPMC6586301 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Detecting carotid stenosis from skin vibrations using Laser Doppler Vibrometry - An in vitro proof-of-concept.

Mancini Viviana V Tommasin Daniela D Li Yanlu Y Reeves Jonathan J Baets Roel R Greenwald Steve S Segers Patrick P

PloS one 20190620 6

Early detection of asymptomatic carotid stenosis may help identifying individuals at risk of stroke. We explore a new method based on laser Doppler vibrometry (LDV) which could allow the non-contact detection of stenosis from neck skin vibrations due to stenosis-induced flow disturbances. Experimental fluid dynamical tests were performed with water on a severely stenosed patient-specific carotid bifurcation model. Measurements were taken under various physiological flow regimes both in a complia ...[more]

PMID: 31220141

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Project description:SignificanceMeasurements of auditory ossicles displacement are commonly carried out by means of laser-Doppler vibrometry (LDV), which is considered to be a gold standard. The limitation of the LDV method, especially for in vivo measurements, is the necessity to expose an object in a straight line to a laser beam operating from a distance. An alternative to this approach is the use of a handheld laser-fiber vibrometry probe (HLFVP) with a curved tip.AimWe evaluate the feasibility of an HLFVP with a curved tip for measuring sound-induced displacement of the auditory ossicles.ApproachA handheld vibrometer probe guiding the laser beam with a fiber-optic cable was used for displacement measurements of the incus body and the posterior crus of the stapes. Tonal stimuli at frequencies of 0.5, 1, 2, and 4 kHz were presented by means of an insert earphone positioned in the outer ear canal. The probe was fixed at the measurement site using a tripod or hand-held by one of the two surgeons.ResultsThe measurements were carried out on six fresh temporal bones. Multivariate analysis of variance showed statistically significant differences for stimulus frequency (F3,143 = 29.37, p < 0.001, and η2 = 0.35), bone (F5,143 = 4.61, p = 0.001, and η2 = 0.01), and measurement site (F1,143 = 4.74, p = 0.03, and η2 = 0.02) in the absence of statistically significant differences for the probe fixation method (F2,143 = 0.15, p = 0.862, and η2 = 0.001). Standard deviations of the means were 6.9, 2.6, 1.9, and 0.6 nm / Pa for frequency, bone, site, and fixation, respectively. Ear transfer functions were found to be consistent with literature data.ConclusionsThe feasibility of applying HLFVP to measure the displacement of auditory ossicles has been confirmed. HLFVP offers the possibility of carrying out measurements at various angles; however, this needs to be standardized taking into account anatomical limitations and surgical convenience.

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Dataset Information

Detecting carotid stenosis from skin vibrations using Laser Doppler Vibrometry - An in vitro proof-of-concept.

Publications

Detecting carotid stenosis from skin vibrations using Laser Doppler Vibrometry - An in vitro proof-of-concept.

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