Chirapapaisan C, Muller RT, Sahin A, et al. - In the present study, the researchers sought to assess the effect of herpes simplex virus (HSV)-induced scar location on bilateral corneal nerve alterations using laser in vivo confocal microscopy (IVCM). Central and peripheral corneal subbasal nerve density (CSND) were evaluated bilaterally in 39 patients with unilateral HSV-induced corneal scars (21 central scars (CS), 18 peripheral scars (PS)) using IVCM. Overall patients showed a significant reduction of CSND in the central and peripheral cornea, compared with controls. As shown by IVCM, patients with HSV scar display a bilateral decrease in CSND. CSND and corneal sensation decrease both in the central and peripheral cornea of the affected eyes, but only in the scar region of the PS group. Interestingly, a drop in CSND was observed locally in the contralateral eyes, corresponding to and mirroring the position of the scar in the affected eyes.