[Preliminary clinical observations of retina injury in alkaline ocular trauma patients]

Objective: To investigate the features of the full-field electroretinogram (FERG) in patients with ocular surface alkaline injury, and to clarify the clinical significance of FERG examination in alkaline ocular trauma. Methods: Retrospective series of case study. A total of 22 patients with chemical ocular surface injury who were treated in the Department of Ophthalmology of Peking University Third Hospital from May 2018 to January 2020 were selected, including 20 males (25 eyes) and 2 females (2 eyes). The age ranged from 19 to 60 years old (average, 41). There were 17 eyes with alkaline ocular trauma, 7 eyes with thermal burn, and 3 eyes with acid ocular trauma. Seventeen contralateral healthy eyes in patients with unilateral mechanical trauma were used as controls. Fourteen alkaline trauma eyes with visual acuity records were further observed according to the degree of visual impairment. All patients were subjected to different flash intensity stimuli in accordance with a standard of the International Society for Clinical Electrophysiology of Vision for dark-adapted and light-adapted full-field FERG. One-way ANOVA and SNK-q was used for the comparison between groups. The unpaired t test was used for the comparison of patients with different vision. Results: Compared with healthy eyes the injured eyes' amplitude of dark adaption FERG b-wave under the dark stimulation of 0.01 cd·s·m^-2 in alkaline ocular trauma, thermal burn, acid ocular trauma was (135±85), (169±55), and (112±43) versus (341±53) μV, respectively; compared with healthy eyes, the differences were statistically significant (F=31.38; q=8.94, 5.70， 5.45；all P<0.01). Compared with healthy eyes the injured eyes' amplitude of dark adaption FERG a-wave under the dark stimulation of 3.00 cd·s·m^-2 in alkaline ocular trauma, thermal burn, acid ocular trauma was (178±78), (172±35), and (99±53) versus (334±60) μV, respectively; compared with healthy eyes, the differences were statistically significant (F=24.33; q=7.04， 5.60， 5.80；all P<0.01). Compared with healthy eyes the injured eyes' amplitude of dark adaption FERG b-wave under the dark stimulation of 3.00 cd·s·m^-2 in alkaline ocular trauma, thermal burn, acid ocular trauma was (354±79), (342±77), and (352±201) versus (600±78) μV, respectively; compared with healthy eyes, the differences were statistically significant (F=27.68; q=8.11， 6.51， 4.48； all P<0.01). Compared with healthy eyes the injured eyes' amplitude of dark adaption FERG OPs under the dark stimulation of 3.00 cd·s·m^-2 in alkaline ocular trauma, thermal burn, acid ocular trauma was (97±54), (107±41), and (45±22) versus (206±32) μV, respectively; compared with healthy eyes, the differences were statistically significant (F=25.03; q=7.36， 5.13， 5.96； all P<0.01).There was no significant difference in FERG between patients with visual acuity≥0.2 and those with visual acuity<0.2 (P>0.05) after alkaline ocular trauma. Conclusions: By detecting the amplitude change of FERG wave form of chemical ocular trauma, in this study, the amplitude of FERG wave form in alkaline ocular trauma was generally decreased. It's suggested that alkaline ocular trauma can cause damage to the rod and cone systems of retinal. (Chin J Ophthalmol, 2020, 56: 514-518).