Corneal neuropathy in central serous chorioretinopathy

Abstract

Purpose: Choroidal sympathetic innervation is impaired in central serous chorioretinopathy (CSCR) (1), throughout mineralocorticoid receptor.(2) We hypothesize that the CSCR condition modifies the entire eyeball innervation system. Corneal nerve shape is easily observed by in vivo confocal microscopy (IVCM).(3) We explored corneal nerves morphology in 2 groups of patients with CSCR and without (CTRL), using vivo confocal microscopy. Methods: We quantified choroid thickness in both groups by OCT-EDI mode (Spectralis; Heidelberg). Patients were free from corneal disease. We explored the central, mid-peripheral, paralimbal and limbal corneal areas of patients with and without CSCR by IVCM (HRT3; Heidelberg). We proceeded with the multilayer module of acquisition and analyzed systematically the subepithelial area (SE), Bowman′s layer (BL), anterior (AS)/intermediate (IS)/deep stroma (DS) (Depth<50μm/50&≤D<150μm/D≥150μm respectively), and endothelium. We semi-quantified as absent (0), rare (1) or common (2) by scoring the morphological corneal nerves abnormalities in both groups. Results: We compared 15 CSCR to 11 age-matched CTRL. While abnormalities were detected sparsely (n=3; in SE, BL and A), 8 CTRL showed normal corneal nerve networks. All CSCR but one displayed nerve abnormalities. Nerve abnormalities were considered as normal, moderate, or severe in respectively 8, 3 and none CRTL versus 1, 3 and 12 CSCR. Nerves alterations were noticeably analogous to each other in all layers for CSCR. More subnormal nerve patterns were observed compared to CTRL in the 5 explored layers (p≤ 0.001). Conclusions: Both thin nerve network and subepithelial plexus are altered in cornea of CSCR patients compared to CTRL, mainly across anterior layers and along straight nerve ramifications crossing the mid stroma of cornea. Nerve fiber abnormalities seems to develop in the cornea of CSCR patients in the absence of clinical corneopathy, and could serve as an early marker for the disease.