1 Vol.:(0123456789) Scientific RepoRtS | (2020) 10:14508 | https://doi.org/10.1038/s41598-020-71546-1 www.nature.com/scientificreports Repeatability and reproducibility of post‑mortem central corneal thickness measurements using a portable optical coherence tomography system in humans: a prospective multicenter study pietro emanuele napoli 1,7* , Matteo Nioi 2,7 , Letizia Gabiati 2 , Michela Laurenzo 2 , Fabio De‑Giorgio 3,4 , Vincenzo Scorcia 5 , Simone Grassi 3 , Ernesto d’Aloja 2 & Maurizio Fossarello 1,6 to assess the repeatability and reproducibility of post‑mortem central corneal thickness ( cct) measurements made by the portable iVue spectra‑domain (SD) optical coherence tomography OCT (Optovue Inc, Fremont, CA) system in humans, and to prospectively establish the time‑course of CCT after death. In a prospective multicenter setting, CCT measurements were obtained from 58 human eyes at the following 16 time‑points after death: immediately (within 2 h), and at each hour by the next 17 h. The range of CCT values for each subject was determined and longitudinal data were used to illustrate the variation in open and close eye mode. All measurements were made by two independent and well‑trained examiners for session. Main outcome measures were intraclass correlation coefcients (ICC), repeatability and reproducibility coefcients, and coefcients of variation of the average central (0–2 mm). Overall, a total of 5,568 OCT measurements were performed by examiners. The repeatability coefcient varied from 0.3 to 1.7% and the reproducibility coefcient varied from 0.3 to 1.6% throughout the entire experimental time frame. Furthermore, the values of the diferent ICCs were also high during the diferent postmortem intervals, thus demonstrating the excellent repeatability and reproducibility of the present OCT approach. When CCT measurements were analyzed longitudinally, corneal thickness showed diferent behavior based on the open or close eye mode. the present study demonstrates that portable oct imaging can be reliably used for corneal pachymetric measurements in supine subjects and during the post mortem period, i.e. without visual fxation and normal physiology/architecture of examined tissues. Optical coherence tomography (OCT) technology has proven to be a signifcant diagnostic tool for improving scientifc knowledge regarding in vivo structures of the anterior and posterior segment of the eye 1–4 . Te use of anterior segment OCT, which provides in vivo imaging of the ocular surface and anterior segment from front to back (the tear flm, conjunctiva, individual corneal layers, sclera, angle and lenticular structures), allows to evaluate tissue anatomy at histological resolution and evaluate diferences in cellular morphology and patterns, open 1 Department of Surgical Science, Eye Clinic, University of Cagliari, Via Ospedale 46, 09124 Cagliari, Italy. 2 Department of Clinical Sciences and Public Health, Forensic Medicine Unit, University of Cagliari, 09124 Cagliari, Italy. 3 Department of Health Surveillance and Bioethics, Section of Legal Medicine, Università Cattolica del Sacro Cuore, Rome, Italy. 4 Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome, Italy. 5 Medical and Surgical Sciences Department, Ophthalmology Operative Unit, Magna Græcia University, Catanzaro, Italy. 6 Clinica Oculistica, San Giovanni di Dio Hospital, Azienda Ospedaliera Universitaria di Cagliari, 09124 Cagliari, Italy. 7 These authors contributed equally: Pietro Emanuele Napoli and Matteo Nioi. * email: pietronapoli@ymail.com