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Background To assess visual quality and stabilization of refractive changes in corneal edema patients after cataract surgery, using visual acuity (VA) and contrast sensitivity measurements. Methods Sixty-one eyes were analysed, twenty-three with and thirty-eight without corneal edema. Uncorrected and corrected distance VA (UDVA and CDVA) were determined with an EDTRS chart, the contrast sensitivity function (CSF) under photopic and mesopic illumination conditions with a CVS-1000e chart, clinical refraction, and corneal topography. Measurements were taken preoperatively, 1–2 days, 1 and 3-months after surgery. Clinical refraction was converted to vector notation (M, J0, J45) and SPSS v26.0 was used for data analysis. Results An improvement of VA was observed through the postoperative period; changes between visits were significant for CDVA in both groups and for UDVA in the edema sample. Significant astigmatic changes (J0,J45) between visits were not observed, but M values showed a hyperopic tendency in the edema group and a myopic shift in the control group that did not change between visits, with statistically significant differences between groups. Controls had significantly better contrast sensitivity at high spatial frequencies. Under mesopic conditions, global contrast sensitivity losses were observed in the edema group, which improved between visits in the middle frequency range. Conclusion Corneal edema patients had a significant reduction of CDVA, and frequency-selective sensitivity losses that evidence a visual quality loss. Clinical refraction may improve visual quality, but in edema patients these losses are related to corneal changes, which did not change at three months after surgery.

Purpose To evaluate whether tobacco affects color vision in young moderate smokers. Methods Chromatic mechanisms of 13 moderate smokers (10–20 cigarettes/day and at least 5 years smoking) and 17 non-smokers in the 18–35 age range were assessed with the Farnsworth-Munsell 100-hue (FM100h) test and short wavelength automated perimetry (SWAP). Results FM100h Total Error Scores (TES) were higher for smokers, and although differences were not significant (p = 0.14), a linear model with principal component analysis was able to explain 95% of the variance in TES and red-green partial error scores, though not in blue-yellow partial error scores (p = 0.07), using the number of years as smokers and the number of cigarettes/day as predictors. SWAP sensitivity values were globally worse (p = 0.002) for smokers (25.7 + 6.2 dB) than for non-smokers (26.7 + 6.2 dB). In the upper visual hemifield sensitivity, total deviation and pattern deviation values were worse for smokers (p 0.05 in both cases). The number of out-of-limits points in the total difference and pattern difference map were significantly larger for smokers. After correcting for multiple comparisons, only the differences in the upper visual hemifield were significant. Conclusions This pilot study suggests that even young moderate smokers show small sensitivity loss in the blue-yellow mechanism, it is statistically significant, restricted to the upper visual hemifield. This corresponds to a retinal region where literature reports a lower density of retinal ganglion cells and where, therefore, the chromatic mechanisms would be more fragile.

Purpose: To analyze the optical quality of intraocular lenses (IOL) with an orange (PC440Y) and a yellow (SN60AT) filter, and correlate these results with the visual quality of patients with these implants. Setting: Fisabio Oftalmología Médica, Valencia, Spain. Design: Randomized prospective study. Materials and Methods: The IOL optical quality was determined using the modulation transfer function (MTF) and the spectral transmission. The visual quality of 87 eyes with cataract (51 with orange filter and 36 with yellow filter) was determined by best corrected visual acuity (BCVA) and contrast sensitivity function (CSF) under photopic and mesopic conditions. To analyze the results, we use a Student's t-test. Results: Orange lens filtered more of the blue spectrum (cut-off wavelength of 370 nm) than the yellow lens (390 nm). The MTF of the yellow lens was better than the orange lens (average modulation of 0.676 for natural and 0.672 for orange). The patients’ BCVA was 0.02 + 0.10 logMAR for both lenses. The CSF obtained with the yellow lens was slightly better, although without statistically significant differences (P > 0.05). Conclusions: Both lenses are of good optical quality. The patients’ visual quality was similar with both lenses, and optical quality was also similar. The color of the lens does not affect the visual quality of the patient.

Purpose. To evaluate the most common lens opacities in Valencia (Spain), analyzed by gender, grade, and type of cataracts. The results are compared with other studies performed at other geographical latitudes and on different races. Methods. A total of 1951 eyes of patients diagnosed with cataracts, aged between 30 and 96 years, were evaluated in accordance with age, gender, type and degree of the cataract, bilaterality and symmetry of this disease. Lens Opacities Classification System III was used to classify the cataract and the degree was graded as mild or moderate to advanced. Results. The most common type of cataract is corticonuclear in the elderly and subcapsular in younger subjects. The most common are nuclear (28.4%) followed by cortical (6.2%), if combined cataracts are ruled out. There is a greater incidence of cortical cataracts in women (70%) and subcapsular cataracts in men (70%). Conclusions. The results suggest the existence of a gender factor in cataract formation and coincide with those obtained in similar studies performed in areas at a similar latitude (40° N) and with different race population. The geographical location (intensity and length of exposure to solar radiation) seems to be a determining factor in the formation of a specific type of cataract, more than race, although there are other factors that contribute in the formation of a specific type of cataract.