Improved visualization of the subthalamic nucleus on synthetic MRI with optimized parameters: initial study.

Area of Science:

• Neuroimaging
• Radiology
• Medical Physics

Background:

• Synthetic magnetic resonance imaging (SyMRI) allows image reconstruction by adjusting magnetic resonance (MR) parameters.
• The subthalamic nucleus (STN) is a critical deep brain structure often targeted in neurological disorder treatments.

Purpose of the Study:

• To determine if customizing MR parameters (TR, TE, TI) in SyMRI can improve STN visualization.
• To compare the efficacy of optimized SyMRI with standard MRI sequences and quantitative susceptibility mapping (QSM).

Main Methods:

• Five healthy volunteers and 22 Parkinson's disease (PD) patients underwent SyMRI and/or QSM.
• Two neuroradiologists optimized SyMRI parameters (TR, TE, TI) for maximum STN-to-parenchyma contrast.
• Qualitative STN scores and contrast-to-noise ratio (CNR) were assessed for regular SyMRI, optimized SyMRI, and QSM.

Main Results:

• Optimized SyMRI yielded significantly higher STN visualization scores compared to regular SyMRI (T2WI, STIR) in both healthy volunteers and PD patients (P < 0.05).
• While optimized SyMRI showed improved CNR over regular SyMRI, QSM demonstrated superior CNR for STN differentiation from the substantia nigra in PD patients (P=0.03).

Conclusions:

• Individualized optimization of MR parameters (TR, TE, TI) in SyMRI can enhance STN conspicuity.
• Optimized SyMRI offers a valuable tool for improving STN visualization, potentially aiding in the diagnosis and treatment of neurological conditions affecting this nucleus.