Purpose: To investigate the relationship between the prognosis and degree of corneal limbal involvement in patients with chemical and thermal injury.
Methods: This retrospective study involved 223 eyes (137 eyes in male and 86 eyes in female patients) of 160 patients (95 males, 65 females; mean age: 38.8±18.6 years) with chemical or thermal injury examined at the Department of Ophthalmology, Kyoto Prefectural University of Medicine between February 1992 and July 2019 (mean observation period: 830.6 days). We classified the severity of the injuries using the Kinoshita classification and examined the prognoses of Grade IIIa, Grade IIIb, and Grade IV cases.
Results: The types of injury included alkali injury (96 eyes, 68 patients), acid injury (35 eyes, 27 patients), thermal injury (19 eyes, 14 patients), and other injury (73 eyes, 51 patients). According to the Kinoshita classification, there were 118 Grade I cases (53%), 48 Grade II cases (22%), 30 Grade IIIa cases (13%), 16 Grade IIIb cases (7%), and 11 Grade IV cases (5%). There were significantly more cases of ≥ Grade IIIb in the thermal-injury group and significantly more cases of ≤ Grade IIIa in the other-injury group. Visual acuity (VA) significantly improved compared with the initial examination in the Grade IIIa cases, but it was poor in the Grade IIIb and IV cases. In four eyes of the Grade IIIb cases, a regeneration of corneal limbal epithelium at several days post injury was observed; ultimately, we arrived at the conclusion that stem cells persisted in the corneal limbus in such cases.
Conclusion: The findings in this study confirmed the following: the survival of corneal limbal epithelium immediately after injury was related to the outcome of VA, the Kinoshita classification was useful for evaluating the prognosis of VA, and the reassessment of the severity at few days post injury provides a more accurate estimation of the prognosis.
Nippon Ganka Gakkai Zasshi (J Jpn Ophthalmol Soc) 125: 725-731,2021.