Kearns-Sayre syndrome: Cerebral folate deficiency, MRI findings and new cerebrospinal fluid biochemical features
Keywords: BH4, tetrahydrobiopterin; CSF, cerebrospinal fluid; 5-HIAA, 5-hydroxyindoleacetic acid; HPLC, high performance liquid chromatography; HVA, homovanillic acid; KSS, Kearns-Sayre syndrome; 5-MTHF, 5-methyltetrahydrofolate; 5-MTHFR, 5-methyltetrahydrofolate r