ClinicalTrials.gg
RecruitingNCT06804707CARPUSUpdated Oct 22, 2026

Carotid Plaque Characterization Using Innovative Ultrasound Techniques

An interventional study of blood sampling and ultrasound imaging exam in Carotid Atheroma, sponsored by Hospices Civils de Lyon. Recruiting at 1 site in France. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-22.

Sponsored by Hospices Civils de Lyon · Not applicable, Interventional, and Basic science

From the registry’s dates

  • Started May 2025; still recruiting 1 year 5 months later.
Updated Oct 22, 2026Now RecruitingSite recruiting status changed+3 moreGo to Updates ↓
Phase
Not applicable
Study type
Interventional
Enrollment
17
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

Strokes are the second leading cause of disability and death worldwide (according to World Health Organization in 2019). They are ischemic in origin in 80% of cases. Atheromatous disease, and more specifically carotid stenosis, is responsible for 20% of these ischemic strokes. Current recommendations, based on high levels of evidence, consider only the degree of carotid artery stenosis to define the threshold for surgical treatment. However, it is now accepted that the composition and rate of progression of atherosclerotic plaque are also criteria to be considered when selecting patients at high risk of stroke. The presence of hemorrhage and a lipid core in the atheromatous plaque, both factors of instability, is associated with a greater risk of ipsilateral ischemic events. The presence of intraplaque hemorrhage is therefore a marker of plaque instability. In this context, techniques for in vivo analysis of atherosclerotic plaque composition need to be developed to better target patients for surgery.

Ultrafast ultrasound enables imaging rates of several thousand images per second. Ultrasound Localization Microscopy (ULM) gives access to the vascular microstructure of tissues: the localization of injected microbubbles, which enhance the ultrasound signal in vessels, and the tracking of these microbubbles enable the vascularization of the tissue in question to be mapped. Ultrasound spectroscopy qualifies tissue microstructure: this operator- and system-independent technique is based on frequency analysis of ultrasound signals backscattered by tissue, and more specifically on analysis of the backscatter coefficient (BSC). Measuring the BSC is intrinsic to the tissue, and provides quantitative parameters on the scatterers to qualify the tissue.

The study hypothesis is that these two ultrasound techniques will provide information on the characteristics of the atherosclerotic plaque: the presence of neovessels and biomarkers linked to its composition, including intraplaque hemorrhage.

02

Conditions studied

  • Carotid Atheroma

Keywords

  • Carotid atheroma
  • Plaque characterization
  • Ultrasound
  • Ultrasound Localization Microscopy
  • Backscatter Coefficient
  • Vasa vasorum
  • Intraplaque Hemorrhage
03

In context

Lead sponsor

Hospices Civils de Lyon is the lead sponsor of 1,854 studies on the registry; 441 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Female or male over 18 years of age
  • Patients with asymptomatic or symptomatic carotid plaque (stenosis> 50% NASCET), referred by the Hospices Civils de Lyon (HCL) vascular surgery consultation and for whom a surgical indication has been retained.
  • Patient having agreed to participate in the study and signed a written informed consent form
  • Patient affiliated to a social security scheme or equivalent.

Exclusion criteria

Exclusion Criteria:

  • Patients with contraindications to Sonovue (right-to-left shunt, severe pulmonary hypertension, allergy to the molecule)
  • Patients with unstable cardiovascular pathology (coronary artery disease, stroke / transient ischemic attack, cardiac rhythm disorders)
  • Uncontrolled hypertension
  • Respiratory distress syndrome
  • Patients with contraindications to MRI (claustrophobia, presence of metallic elements, etc.).
  • Gadolinium-related contraindications and precautions for use
  • Contraindication to dobutamine
  • Hypersensitivity to the active substance or to one of the constituents of Gadolinium,
  • Renal insufficiency with clearance \<30 ml/min/1.73 m²,
  • Pregnant or breast-feeding patients
  • Patients under guardianship or trusteeship
05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
17 participants (estimated)

Study arms

  • Experimental
    patients with carotid plaque

    Patients over 18 years of age with asymptomatic or symptomatic carotid plaque with a degree of stenosis \> 50% North American Symptomatic Carotid Endarterectomy Trial (NASCET) from vascular surgery consultations and for whom a surgical indication has been retained

    Biological: blood sampling · Device: ultrasound imaging exam · Device: High resolution MRI plaque exam

Interventions

  • Biologicalblood sampling

    This procedure will take place once during the patient's CARPUS first visit (Croix Rousse hospital (Hospice civils de Lyon). A peripheral venous line of the cathlon 24 G type with tap without tubing will be inserted by a nurse. A blood sample will be taken at the same time to check creatinine levels before the MRI scan and to record the patient's cholesterol levels for the eCRF.

  • Deviceultrasound imaging exam

    This procedure takes place once immediately after the intervention 1. The patient will first have an ultrasound acquisition with the clinical ultrasound scanner (\~5 minutes) in order to locate the plaque. An acquisition with the research ultrasound scanner and matrix probe will then be performed for measurement for ultrasound spectroscopy (\~5 minutes). An injection of 2.4 ml Sonovue followed by 10 ml saline will be performed during acquisition with the research ultrasound scanner for ultrasound localization imaging measurement (\~10 minutes). The patient must remain under observation (in the waiting room) for 30 minutes after the examination.

  • DeviceHigh resolution MRI plaque exam

    This procedure will take place once during the patient's CARPUS second visit (Pierre Wertheimer hospital (Hospice civils de Lyon)). The patient is greeted in radiology, and his/her identity and absence of contraindications are verified. A peripheral venous line of the cathlon 24 G type with tap without tubing will be inserted by a nurse. Injection of gadolinium and MRI examination of the plaque used in clinical routine.

06

What researchers measure

Primary outcomes

  1. Volume of neovessels in carotid atherosclerotic plaques by ULM

    From the vascularization cartography obtained by ULM, the volume of vascularization of the plaque will be estimated (number of pixels with vascularization compared with the number of pixels in the plaque x100). Plaques can then be described by neovessel volume distribution.

    Time frame: between 6 and 59 days after inclusion

  2. Mean velocity in neovessels in carotid atherosclerotic plaques by ULM

    From the vascularization cartography obtained by ULM, the mean velocity (mm/s) in all the neovessels will be estimated.

    Time frame: between 6 and 59 days after inclusion

  3. Location of neovessels in carotid atherosclerotic plaques by ULM

    The main location of vessels will also be described according to their topography in the plaque (e.g. central, peripheral, both).

    Time frame: between 6 and 59 days after inclusion

Secondary outcomes

  1. Lizzi Feleppa slope (dB/MHz) derived from BSC measured by ultrasound spectroscopy on carotid atherosclerotic plaques

    In ultrasound signals, the plaque is divided into regions of interest and ultrasound spectroscopy is applied. This will enable us to obtain the backscatter coefficient (BSC) for each region of interest. From the backscatter coefficient, parameters derived from the BSC will be evaluated. One of these parameters is: \- Lizzi-Feleppa slope: slope of the linear fit of the BSC as a function of frequency. This parameter in the different regions of interest on the plaque will be averaged for each plaque.

    Time frame: between 6 and 59 days after inclusion

  2. Lizzi Feleppa intercept (dB) derived from BSC measured by ultrasound spectroscopy on carotid atherosclerotic plaques

    In ultrasound signals, the plaque is divided into regions of interest and ultrasound spectroscopy is applied. This will enable us to obtain the backscatter coefficient (BSC) for each region of interest. From the backscatter coefficient, parameters derived from the BSC will be evaluated. One of these parameters is: \- Lizzi-Feleppa intercept: intercept of the linear fit of the BSC as a function of frequency. This parameter in the different regions of interest on the plaque will be averaged for each plaque.

    Time frame: between 6 and 59 days after inclusion

  3. Lizzi Feleppa midband (dB) derived from BSC measured by ultrasound spectroscopy on carotid atherosclerotic plaques

    In ultrasound signals, the plaque is divided into regions of interest and ultrasound spectroscopy is applied. This will enable us to obtain the backscatter coefficient (BSC) for each region of interest. From the backscatter coefficient, parameters derived from the BSC will be evaluated. One of these parameters is: \- Lizzi-Feleppa midband: midband of the linear fit of the BSC as a function of frequency. This parameter in the different regions of interest on the plaque will be averaged for each plaque.

    Time frame: between 6 and 59 days after inclusion

  4. Integrated backscatter coefficient (BSC) (dB) measured by ultrasound spectroscopy on carotid atherosclerotic plaques

    In ultrasound signals, the plaque is divided into regions of interest and ultrasound spectroscopy is applied. This will enable us to obtain the backscatter coefficient (BSC) for each region of interest. From the backscatter coefficient, parameters derived from the BSC will be evaluated. One of these parameters is: \- integrated BSC: Integrated BSC on the -6 dB frequency bandwidth. This parameter in the different regions of interest on the plaque will be averaged for each plaque.

    Time frame: between 6 and 59 days after inclusion

  5. Acoustic attenuation (dB/mm) measured by ultrasound on carotid atherosclerotic plaques

    In ultrasound signals, the plaque is divided into regions of interest and ultrasound spectroscopy is applied. This will enable us to obtain the backscatter coefficient (BSC) for each region of interest. From the backscatter coefficient, parameters derived from the BSC will be evaluated. One of these parameters is: \- acoustic attenuation. This parameter in the different regions of interest on the plaque will be averaged for each plaque.

    Time frame: between 6 and 59 days after inclusion

  6. Correlation between the volume of neovessels in carotid atherosclerotic plaques, estimated by ULM, and that estimated by anatomopathological analyses

    For each plaque, histological analysis will give the stage of intraplaque haemorrhage according to Derksen's grading scale if intraplaque haemorrhage is present. A semi-quantitative grading denoting the quantity of neovessels (score between 0 and 3) will also be performed. The correlation between these grades and the volume of neovessels originating from the ULM will be studied.

    Time frame: between 6 and 59 days after inclusion

  7. Correlation between ultrasound parameters of BSC related to intraplaque hemorrhage of carotid atherosclerotic plaques and intraplaque hemorrhage assessed by anatomopathological analyses

    Histological analysis will give the stage of intraplaque haemorrhage according to Derksen's grading scale if intraplaque haemorrhage is present. A semi-quantitative scale denoting the ratio of the area of intraplaque hemorrhage to the total area of the plaque (score 0 if ratio between 0 and 25%, score 1 if ratio between 25 and 50%, score 2 if ratio between 50 and 75% and score 3 if ratio between 75 and 100%). The thresholds for the BSC parameters need to be calibrated to determine the thresholds corresponding to intraplaque hemorrhage. For this step, areas of intraplaque hemorrhage will be localized using plaque MRI. This will enable us to determine which BSC parameter or combination of parameters best characterizes intraplaque hemorrhage, and then to estimate for each plaque a relative volume of region of interest containing intraplaque hemorrhage. The correlation between these grades and the volume of intraplaque hemorrhage derived from ultrasound measurements will be studied.

    Time frame: between 6 and 59 days after inclusion

07

Study locations

1 of 1 sites recruiting
  • Hôpital de la Croix Rousse
    Lyon, 69004, France
    • Dr. Ariane BLEROT, MD, PhD · Contact · ariane.blerot@chu-lyon.fr · +33.04.72.07.16.78
    • Dr Ariane BLEROT, MD, PhD · Principal investigator
    Recruiting
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Timeline

1 registry update since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedDate before it movedWhere the date was before it moved

Started May 2025 (actual). Primary completion is estimated for Feb 2027, 21 months after the start.

Since we started tracking on Sep 25, 2026, the dates moved once, on Oct 22, 2026: start Mar 2025 → May 2025, primary completion Jan 2027 → Feb 2027 and completion Jan 2027 → Feb 2027.

Earlier changes are on the record history on ClinicalTrials.gov ↗

How these figures are worked out, and which studies are left out of them.

Registered
Jan 27, 2025
First posted
Feb 3, 2025
StartActual
May 13, 2025was Mar 2025
Primary completionEst.
Feb 13, 2027was Jan 2027
CompletionEst.
Feb 13, 2027was Jan 2027
Last update
Oct 22, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
Status
Not yet recruiting→Recruiting
changed Oct 22, 2026
Sites
Hôpital de la Croix Rousse is now Recruiting
Oct 22, 2026
Start date
Mar 10, 2025→May 13, 2025 (actual)
Oct 22, 2026
Primary completion
Jan 10, 2027→Feb 13, 2027
Oct 22, 2026
Study completion
Jan 10, 2027→Feb 13, 2027
Oct 22, 2026
Show all 1 update
  1. Oct 22, 2026
    Not yet recruiting→Recruiting
    Hôpital de la Croix Rousse is now Recruiting
    Start date Mar 10, 2025→May 13, 2025 (now actual)
    Primary completion Jan 10, 2027→Feb 13, 2027
    Study completion Jan 10, 2027→Feb 13, 2027
    + 2 other changes: verification date and oversight details

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT06804707
Responsible party
Sponsor
First posted
Feb 3, 2025
Start date
May 13, 2025
Primary completion
Feb 13, 2027 (estimated)
Completion
Feb 13, 2027 (estimated)
Last update
Oct 22, 2026

Study contacts

Dr. Ariane BLEROT, MD, PhD
Contact
ariane.blerot@chu-lyon.fr
+33 4.72.07.16.78
Pauline MULEKI-SEYA, PhD
Contact
pauline.muleki-seya@creatis.insa-lyon.fr
+33 4.72.43.83.32
Dr Ariane BLEROT, MD, PhD
principal investigator · Hospices Civils de Lyon

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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