NEFL and amyotrophic lateral sclerosis: Two CSF neurofilaments, phosphorylated neurofilament heavy chain(pNfH) and neurofilament light chain (NfL), are released into the blood and CSFfollowing axonal degeneration.107 PNfH and NfL are validated diagnostic biomarkers for ALS but more directmeasures of BCNSB dysfunction could facilitate diagnosis prior to the onset ofneuronal damage.