Preservative-free drops better than preserved drops after cataract surgery

This randomized study found that the signs and symptoms of dry eye were significantly reduced after cataract surgery followed by the use of preservative-free sodium hyaluronate 0.1% and fluorometholone 0.1% eye drops compared with preserved drops. They also found that preservative-free fluorometholone drops may have anti-inflammatory and antioxidant effects in the tears of dry eye patients.

While so few doctors pay attention to the preservative overload effect of the postop regimen, I feel that, as this study implies, only preservative-free tears should be offered.

They randomized 80 patients with pre-existing dry eye undergoing cataract surgery at a hospital in South Korea to postoperative preservative-free sodium hyaluronate 0.1% and preservative-free fluorometholone 0.1% eye drops four times a day in the first month and twice a day in the second month, or preserved eye drops using the same schedule.

At two months, the ocular surface disease index score, tear-film breakup time, Schirmer I score, fluorescein staining score, impression cytology findings and goblet cell count were significantly better in the preservative-free drop group than in the preserved drop group (P < 0.05).

The interleukin-1β and tumor necrosis factor-α concentrations were significantly less in the tears of preservative-free group than in the tears of the preserved drop group, and catalase and superoxide dismutase 2 fluorescence intensities were significantly greater in the tears of the preservative-free group than in the tears of the preserved group (P < 0.05).

The authors hypothesize that the combination of preservative-free steroid and lubricant eye drops may relieve pre-existing dry-eye syndrome by decreasing the oxidative and inflammatory damage to the ocular surface in patients after cataract surgery.

They say that a large multicenter trial with a prolonged follow-up is needed to conclusively determine the efficacy of preservative-free steroid and lubricant combination eye-drop therapy.