Recent Advances in Transducers for Intravascular Ultrasound (IVUS) Imaging

Abstract

As a well-known medical imaging methodology, intravascular ultrasound (IVUS) imaging plays a critical role in diagnosis, treatment guidance and post-treatment assessment of coronary artery diseases. By cannulating a miniature ultrasound transducer mounted catheter into an artery, the vessel lumen opening, vessel wall morphology and other associated blood and vessel properties can be precisely assessed in IVUS imaging. Ultrasound transducer, as the key component of an IVUS system, is critical in determining the IVUS imaging performance. In recent years, a wide range of achievements in ultrasound transducers have been reported for IVUS imaging applications. Herein, a comprehensive review is given on recent advances in ultrasound transducers for IVUS imaging. Firstly, a fundamental understanding of IVUS imaging principle, evaluation parameters and IVUS catheter are summarized. Secondly, three different types of ultrasound transducers (piezoelectric ultrasound transducer, piezoelectric micromachined ultrasound transducer and capacitive micromachined ultrasound transducer) for IVUS imaging are presented. Particularly, the recent advances in piezoelectric ultrasound transducer for IVUS imaging are extensively examined according to their different working mechanisms, configurations and materials adopted. Thirdly, IVUS-based multimodality intravascular imaging of atherosclerotic plaque is discussed. Finally, summary and perspectives on the future studies are highlighted for IVUS imaging applications.

Advanced Neuroimaging Role in Traumatic Brain Injury: A Narrative Review

“…Similarly, a patient with traumatic carotid-cavernous fistula was successfully monitored by intravascular US and accurate coil embolization was achieved ( Nishio et al, 2009 ). Although intravascular US has shown the high diagnostic accuracy in large vessels, further application of intravascular US in TBI would require a smaller US transducer that can be placed in the cerebral vessels ( Peng et al, 2021 ). With the development of hardware size, portability and resolution, intravascular US will play a critical role in traumatic vessel imaging following TBI.…”

A Transparent Ultrasound Array for Real-Time Optical, Ultrasound, and Photoacoustic Imaging

“…In this case, fluorescence imaging provided the surface projection of the targeted Cetuximab-IRDye800 agent, PA imaging showed the depth resolved optical absorption contrast from the IRDye800 and surrounding vasculature, and ultrasound imaging revealed the underlying tissue anatomy. For imaging atherosclerosis, a cardiovascular disease characterized by the accumulation of lipid plaques and several fibrous and cellular constituents, intravascular ultrasound (IVUS) and optical coherence tomography (OCT) technologies are commonly used in the clinics [16][17][18]. Recently, intravascular PA (IVPA) is also being actively studied for mapping deep tissue atherosclerosis based on high optical absorption contrast of plaque lipids in the NIR-IIb (1.5 μm-1.7 μm) optical window [19][20][21][22][23].…”

Current research and future prospects of IVOCT imaging‐based detection of the vascular lumen and vulnerable plaque

“…IVOCT inherits high resolution and high sensitivity from OCT. The spatial resolution can reach 10-20 μm, which is 10 times that of IVUS, the former "gold standard" of intravascular imaging [19]. It can better observe and measure the thickness of the plaque fibrous cap, find tiny fibrous cap ruptures, identify macrophage aggregation in the plaque and accurately observe the tissue ultrastructure [20], so it is called "optical biopsy" [21].…”