Vitrectomy-Associated Endophthalmitis and COVID-19

Vitrectomy-associated endophthalmitis is a rare but severe complication that can cause significant visual impairment. Recent reports have highlighted a potential increase in endophthalmitis cases related to intravitreal injections during the COVID-19 pandemic, possibly due to the widespread use of face masks. To investigate how the use of face masks may affect rates of vitrectomy-associated endophthalmitis, the authors of this study conducted a retrospective analysis of medical records of vitrectomy patients from 31 centers in Japan. The aim was to compare the incidence of endophthalmitis between two groups: those who underwent a vitrectomy before the pandemic (January 2019 to December 2019) and those who underwent a vitrectomy during the pandemic (July 2020 to June 2021) when mask use was mandatory.

The study found that out of 16,568 surgeries in the pre-COVID-19 period, 18 cases of endophthalmitis occurred (0.11%). During the COVID-19 period, out of 14,929 surgeries, 31 cases of endophthalmitis occurred (0.21%; P=.031, OR=1.913, 95% CI 1.078 to 3.394). However, the authors found no significant difference between the two time frames when subdividing phacovitrectomies from vitrectomies.

The authors suggested that the increased incidence of endophthalmitis during the pandemic could be related to mask use, which may have led to higher contamination rates during the postoperative period. They noted a higher incidence of endophthalmitis caused by oral bacteria and an unusual case of S. lugdunesis, implicating more frequent touching of the backside of the auricle during face mask use.

The study's findings on final visual acuity demonstrated a mean final best-corrected visual acuity of approximately 0.5 logMAR in both groups, roughly equal to about 20/60 Snellen visual acuity. This was better than previous reports and could be attributed to early detection of infections, early treatment with broad-spectrum antibiotics, less virulent infections, or misdiagnosis of noninfectious inflammation.

The study's limitations include its retrospective nature, focus on the Japanese population, and failure to account for other factors that may have influenced endophthalmitis incidence. These factors include surgical techniques, instrumentation standardization, mask type, duration of use, and mask fit.

In conclusion, this study suggests that using face masks after vitrectomy surgery may increase the risk of endophthalmitis. However, caution should be used when generalizing the findings to different populations and health care systems. Further research is necessary to confirm these findings and develop strategies to minimize the risk of vitrectomy-associated endophthalmitis.