Real-time interactive MR imaging system: sequence optimization, and basic and clinical evaluations.

S Naganawa; T Ishiguchi; T Ishigaki; K Sato; T Katagiri; H Kishimoto; T Mimura; O Takizawa; C Imura

PubMed · 10852660

Real-time interactive MR imaging system: sequence optimization, and basic and clinical evaluations.

S Naganawa·T Ishiguchi·T Ishigaki·K Sato·T Katagiri·H Kishimoto·T Mimura·O Takizawa·C Imura

Abstract

A real-time interactive MR imaging system (real-time MRI) is an MR scanner which has a fast image updating cycle and the ability to freely change slice orientation, just like an ultrasound imaging system. Recently, such a system has been developed and installed on a clinical 1.5-Tesla system. The purpose of this study was to optimize the pulse sequences for clinical use and to evaluate the clinical usefulness and basic functionality of real-time MRI. For T1-weighted imaging, FLASH (fast low angle shot) can be selected, and up to 5 frames per second can be acquired depending on the matrix size. For T2-weighted imaging, true FISP (fast imaging with steady-state precession) can be selected, and up to 4 frames per second can be acquired. Maximum C/N between liver and spleen was obtained at a flip angle of 20 degrees on FLASH. Maximum C/N between cardiac cavity and wall was obtained at a flip angle of 60 degrees on true FISP. Localization of the right and left coronary arteries could be performed within 30 seconds in three volunteers. Although the present real-time MRI system has drawbacks such as low spatial resolution and relatively low contrast resolution, we expect real-time MRI to be one of the most important tools for future clinical MRI.

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S Naganawa, T Ishiguchi, T Ishigaki, K Sato, T Katagiri, H Kishimoto, T Mimura, O Takizawa, C Imura. Real-time interactive MR imaging system: sequence optimization, and basic and clinical evaluations.. https://pubmed.ncbi.nlm.nih.gov/10852660/

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