Analyzer-based phase-contrast x-ray imaging of carotid plaque microstructure

Area of Science:

• Medical Imaging
• Cardiovascular Research
• Biomedical Engineering

Background:

• Plaque vulnerability is linked to its composition, necessitating advanced imaging for stability prediction.
• X-ray phase-contrast (PC) imaging offers high-contrast soft-tissue visualization.
• Multiple image radiography (MIR) is explored for human carotid artery plaque evaluation.

Purpose of the Study:

• To assess the efficacy of MIR, an x-ray PC technique, in evaluating human carotid artery plaque composition and structure.
• To compare MIR's imaging capabilities against ultrasound and conventional radiography for plaque characterization.

Main Methods:

• Human carotid plaques were imaged using ultrasound, then excised and formalin-fixed.
• Multiple image radiography (MIR) was performed using synchrotron radiation.
• Conventional radiographs were acquired for comparison, and image texture measures were computed.

Main Results:

• Ultrasound showed homogeneous plaques without calcifications, contrasting with MIR findings.
• MIR images revealed heterogeneous structures and microcalcifications, correlating with histology.
• MIR images demonstrated significantly more texture in specific regions than conventional radiographs (P < .05).

Conclusions:

• X-ray PC imaging, specifically MIR, provides superior depiction of plaque soft-tissue heterogeneity compared to ultrasound and conventional radiography.
• MIR imaging shows promise as a viable technique for identifying high-risk carotid artery plaques.
• Further investigation of MIR is recommended for its clinical application in plaque risk assessment.