Neurochemicals that are present in large millimolar quantities can be assessed using proton magnetic resonance spectroscopy (1H-MRS), which is a non-invasive MR technique that can measure levels of N-Acetyl Aspartate (NAA, neuronal marker), total Creatine (tCr, metabolic marker), total Choline (tCho, cell-membrane marker), and Myo-inositol (mI, glial marker). However, quantitative MRS has lower spatial resolution and requires advanced sequences and post-processing compared to structural MRI, making it less commonly used in the clinical setting. However, MRS can provide insights into the chemistry underlying structural changes, and chemical alterations commonly precede structural abnormalities during disease progression.
