A new classification for epidemiological study of mechanical eye injuries.

Objective: Considering the difficulty in classifying some cases with eye trauma by Birmingham Eye Trauma Terminology (BETT) in our epidemiological study, we introduce a new classification for epidemiological study of mechanical eye injuries based on BETT.

Methods: A retrospective investigation was carried out in 31 hospitals from January 2005 to December 2010. All medical records of inpatients with eye injuries were reviewed. A total of 10 718 patients (11 227 eyes) were diagnosed as mechanical eye injuries. All mechanical eye injuries were tried to be classified using BETT. While some eye injuries were difficult to categorize. We recorded the injury type and case number. A new classification based on BETT was also used for the same project.

Results: Of 10 718 patients (11 227 eyes) with mechanical eye injuries, the following cases cannot be classified by BETT: 1 488 patients (1 559 eyes) with merely orbital or ocular adnexa injury, 1 961 (2 054) globe injuries associated with orbital or ocular adnexa injury, 271 (284) ocular surface foreign body (OSFB) or ocular wall foreign body (OWFB), 77 (89) contusion, 9 (11) lamellar laceration associated with OSFB or OWFB, 29 (30) rupture associated with OSFB, OWFB or intraocular foreign body and 60 (62) lace- ration associated with OSFB or OWFB. While according to our new classification, all eye injuries can be categorized without any difficulty.

Conclusion: Difficulty in classifying some eye injuries in epidemiological study by BETT brings some trouble to our study, which can be solved by our new eye injury classification to some extent. It is hoped that other ophthalmologists present better ones to make the classification more perfect.