Psychophysical Measurements of Luminance Contrast Sensitivity and Color Discrimination with Transparent and Blue-Light Filter Intraocular Lenses.

INTRODUCTION: The purpose of this study was to measure luminance contrast sensitivity and color vision thresholdfs in normal subjects using a blue light filter lens and transparent intraocular lens material. METHODS: Monocular luminance grating contrast sensitivity was measured with Psycho for Windows (version 2.36; Cambridge Research Systems) at 3.0, 6.0, 12.0, 20.0, and 30.0 cycles per degree of visual angle (cpd) in 15 normal subjects (eight female), with a mean age of 21.6 years (SD = 3.8 years). Chromatic discrimination was assessed with the Cambridge colour test (CCT) along the protan, deutan, and tritan color confusion axes. Both tests were performed in a darkened room under two situations: with a transparent lens and with blue light filter lens. Subjective impressions were taken by subjects regarding their visual experience under both conditions. RESULTS: No difference was found between the luminance contrast sensitivity measured with transparent and blue light filter. However, 13/15 (87%) of the subjects reported more comfortable vision with the blue filter. In the color vision test, tritan thresholds were significantly higher for the blue filter compared with the transparent filter (p = 0.003). For protan and deutan thresholds no differences were found. CONCLUSION: Blue-yellow color vision is impaired with the blue light filter, and no impairment occurs with the transparent filter. No significant differences in thresholds were found in the luminance contrast sensitivity comparing the blue light and transparent filters. The impact of short wavelength light filtering on intrinsically photosensitive retinal ganglion cells is also discussed.

Comparison between results of trabeculectomy in primary congenital glaucoma with and without the use of mitomycin C.

PURPOSE: To evaluate the results of trabeculectomy with and without the use of mitomycin C in children with primary congenital glaucoma. METHODS: The authors retrospectively studied the data of 91 patients who underwent the first trabeculectomy for primary congenital glaucoma, with 19 years of follow-up. Success criteria were set with two distinct values of intraocular pressure: lower or equal to 15 mm Hg or lower than 21 mm Hg and separately analyzed. RESULTS: Among the studied patients, 61 had undergone trabeculectomy without mitomycin C and 30 with mitomycin C. The comparison between the groups of patients showed age homogeneity (P = 0.152) and did not demonstrate any difference in preoperative (P = 0.234) and postoperative (P = 0.907) intraocular pressure. Success rates through time, for both pressure limits was not different between the groups. Both age and the presence of previous trabeculotomy did not influence the success of trabeculectomy through time, for the two pressure limits considered. The complication rate was higher among the patients who received mitomycin C (P = 0.010). CONCLUSIONS: The success of trabeculectomy for primary congenital glaucoma with mitomycin C was not different than that of trabeculectomy with mitomycin C in the studied patients. Mitomycin C was associated with a higher incidence of complications.