Effect of tinted optical filters on visual acuity and contrast sensitivity in patients with inflammatory cystoid...

To ascertain the effect of tinted optical filters (TFs) on visual function in patients with inflammatory cystoid macular edema (CME).

A prospective study included 14 patients with inflammatory CME and best-corrected visual acuity between 0.1 and 0.8 (CME group) and 16 sex-, age-, and best-corrected visual acuity-matched patients with macular disorders but no CME (non-CME group). All patients from both groups underwent the following tests: determination of visual acuity at distance, contrast sensitivity (CS) testing; and subjective grading of each TF for best-corrected visual acuity and CS compared with no TFs. All tests were performed with the following TFs: Corning photochromic filter with a cutoff at 450 nm; Zeiss filter with a cutoff at 560 nm; and cheap widely available yellow filter with a cutoff at 489 nm.

Without TFs, the CME and non-CME groups did not differ in best-corrected visual acuity (P = 0.79). Using the TFs, a clinically significant improvement was not achieved by any patient. However, using the definition of any improvement, best-corrected visual acuity with all TFs showed a significant improvement in the CME group compared with no TFs (P < 0.01). The CME group rated the Corning photochromic filter with a cutoff of 450 nm significantly higher than the other TFs when determining visual acuity (P = 0.05) and CS (P = 0.01) in contrast to no improvement in the non-CME group.

Although the use of TFs for the CME patients was not associated with criteria of clinically significant improvement, our results indicate that visual acuity and CS in patients with inflammatory CME might benefit from the use of TFs.