Rate of Post-traumatic Endophthalmitis with or without Injection of Balanced Salt Solution

Purpose: In a study complementing a previous multicenter randomized clinical trial on prophylactic injection of intraocular antibiotics during primary repair of penetrating eye injuries (PEIs), we sought to determine whether needle entrance and injection of balanced salt solution (BSS), per se, could increase the rate of acute post-traumatic bacterial endophthalmitis (APBE). Methods: Patients randomized to the BSS injection arm (n=167) of the Traumatic Endophthalmitis Trial, and eligible patients who had refused enrollment and received no intraocular injections during primary repair (n=111) were compared for the development of APBE. Results: APBE occurred in 8 of 167 (4.8%) eyes in the BSS group and in 5 of 111 (4.5%) eyes in the non-injection group (P=0.91). Retained intraocular foreign bodies were present in 46 eyes including 25 (15%) eyes in the BSS injection group and 21 (18.9%) eyes in the non-injection group (P=0.38). Logistic regression analysis showed no significant difference between BSS injected and non-injected eyes in terms of APBE (P=0.69). However, the presence of intraocular foreign bodies was strongly associated with the risk of endophthalmitis (P<0.001, OR=14.1, 95% CI: 4.1-48.5). Conclusion: Needle entrance and intraocular injection of BSS during primary repair of PEIs does not increase the risk of APBE.