Early Detection of Nerve Fiber Loss by Corneal Confocal Microscopy and Skin Biopsy in Recently Diagnosed Type 2 Diabetes

We sought to determine whether early nerve damage may be detected by corneal confocal microscopy (CCM), skin biopsy, and neurophysiological tests in 86 recently diagnosed type 2 diabetic patients compared with 48 control subjects. CCM analysis using novel algorithms to reconstruct nerve fiber images was per-formed for all fibers and major nerve fibers (MNF) only. Intraepidermal nerve fiber density (IENFD) was assessed in skin specimens. Neurophysiological measures in-cluded nerve conduction studies (NCS), quantitative sensory testing (QST), and cardiovascular autonomic function tests (AFTs). Compared with control subjects, diabetic patients exhibited significantly reduced corneal nerve fiber length (CNFL-MNF), fiber density (CNFD-MNF), branch density (CNBD-MNF), connecting point