Provitera V, et al. - The objective herein was to examine the clinical utility of leg to thigh intraepidermal nerve fiber (IENF) density ratio as a parameter to discriminate between length-dependent small fiber neuropathy (SFN) and small fiber sensory ganglionopathy (SFSG) in individuals with signs and symptoms of small fiber pathology. Findings demonstrated that the leg to thigh IENF density ratio was substantially lower in patients with length-dependent SFN vs patients with SFSG. It was deduced that the leg to thigh IENF ratio was a valuable instrument in the differential diagnosis between SFSG and length-dependent SFN.