Synthetic CT in Musculoskeletal Disorders A Systematic Review

Repeated computed tomography (CT) examinations increase patients' ionizing radiation exposure and health costs, making an alternative method desirable. Cortical and trabecular bone, however, have short T2 relaxation times, causing low signal intensity on conventional magnetic resonance (MR) sequences. Different techniques are available to create a CT-like contrast of bone, such as ultrashort echo time, zero echo time, gradient-echo, and susceptibility-weighted image MR sequences, and artificial intelligence. This systematic review summarizes the essential technical background and developments of ultrashort echo time, zero echo time, gradient-echo, susceptibility-weighted image MR imaging sequences and artificial intelligence; presents studies on research and clinical applications of CT-like MR imaging; and describes their main advantages and limitations. We also discuss future opportunities in research, which patients would benefit the most, the most appropriate situations for using the technique, and the potential to replace CT in the clinical workflow.

Automated summary

This systematic review provides an overview of alternative methods to computed tomography (CT), such as ultrashort echo time, zero echo time, gradient-echo, susceptibility-weighted image MR sequences, and artificial intelligence. It summarizes the technical background, research and clinical applications, advantages, limitations, and future opportunities for these techniques.