Corneal neuropathy in central serous chorioretinopathy

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. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study was partly funded by the npo CRO tous unis pour la vision ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics committee/IRB of French National IRB committee gave ethical approval for this work under the #2022-A02713-40 I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as [ClinicalTrials.gov][1]. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors [1]: http://ClinicalTrials.gov