Real-time MRI: a new tool of radiologic imaging in small children

Abstract

Real-time MRI (rt-MRI) in children is a new imaging technique that combines the advantages of US — at frame rates of up to 50 images per second — with the quality and features of MRI. Although still subject of research, it has become a standard tool in the diagnostic portfolio of two pediatric radiology departments in Germany. Based on ultrashort acquisition times, any detrimental effects of macroscopic movements of the child and the physiological movements of the organs are negligible. Especially in pediatric brain imaging, rt-MRI has already proven its value. With suitable indications, rt-MRI can reduce anesthesia and sedation examinations in children below 6 years of age by 40% due to its very short examination time and its robustness to motion. There is a high level of acceptance among parents and referrers when diagnostic possibilities and limitations are communicated correctly. Conclusion: Completely new diagnostic possibilities arise in the imaging of the moving lung, the beating heart, joint movements, and speaking and swallowing, as demonstrated in this video-backed review. What is known:• MRI in moving children has been burdened with severe artifacts.• Gross motion usually has to be handled by sedation and periodic motion of the heart and lungs has to be compensated with time-consuming techniques until now. What is new:• Real-time MRI allows image acquisition with up to 50 frames per second similar to ultrasound frame rate.• Real-time MRI proofs to be very promising for imaging children, reducing examination time and sedation rate drastically.

As fast as an X-ray: real-time magnetic resonance imaging for diagnosis of idiopathic scoliosis in children and adolescents

“…For planning, conventional FLASH sequences were used from the skull base to the proximal femur, followed by a rapid T2/T1-weighted volume coverage sequence in both coronal and sagittal orientations with an equal field of view. This real-time MRI sequence leverages an ultra-fast frame rate to scan a larger volume within a few seconds [17][18][19]. Three coronal and sagittal stacks were acquired and stitched together before analysis.…”

“…A novel, fast low-angle shot MRI technique (FLASH 2.0) can now provide a radiation-free, ultra-fast alternative to radiography suitable for daily use. With up to 50 frames per second, FLASH 2.0 real-time MRI is largely unaffected by motion [17][18][19]. Three stacks covering a field of view from the posterior fossa to the greater trochanter can be acquired within 30 s. The loss of image quality in depecting the vertebral endplates when obtaining the measurements is acceptable.…”