Unlike previous methods, such as ELISA, the Simoa method can accurately measure even low concentrations of NfL and shows a high correlation between CSF and blood.[18] Therefore, serum NfL measurement using the Simoa method can be a useful noninvasive biomarker for ischemic stroke, especially in cases that cannot undergo MRI or have negative results on MRI. The gene discussed is NEFL; the disease is ischemic stroke.