Relationship between postoperative refractive outcomes and cataract density: multiple regression analysis.

PURPOSE: To evaluate the relationship between cataract density and the deviation from the predicted refraction. SETTING: Department of Ophthalmology, Nara Medical University, Kashihara, Japan. METHODS: Axial length (AL) was measured in eyes with mainly nuclear cataract using partial coherence interferometry (IOLMaster). The postoperative AL was measured in pseudophakic mode. The AL difference was calculated by subtracting the postoperative AL from the preoperative AL. Cataract density was measured with the pupil dilated using anterior segment Scheimpflug imaging (EAS-1000). The predicted postoperative refraction was calculated using the SRK/T formula. The subjective refraction 3 months postoperatively was also measured. The mean absolute prediction error (MAE) (mean of absolute difference between predicted postoperative refraction and spherical equivalent of postoperative subjective refraction) was calculated. The relationship between the MAE and cataract density, age, preoperative visual acuity, anterior chamber depth, corneal radius of curvature, and AL difference was evaluated using multiple regression analysis. RESULTS: In the 96 eyes evaluated, the MAE was correlated with cataract density (r = 0.37, P = .001) and the AL difference (r = 0.34, P = .003) but not with the other parameters. The AL difference was correlated with cataract density (r = 0.53, P<.0001). CONCLUSION: The postoperative refractive outcome was affected by cataract density. This should be taken into consideration in eyes with a higher density cataract.

Impact of nuclear cataract density on postoperative refractive outcome: IOL Master versus ultrasound.

PURPOSE: To evaluate the effect of cataract density on the postoperative refractive outcome. METHODS: For 59 nuclear cataract eyes, the axial length was preoperatively measured by the IOL Master (Zeiss, Germany) and ultrasound (US; UD-6000, Tomey, Japan) and the cataract density by EAS-1000 (Nidek, Japan). The prediction error was used as evaluation of the accuracy of ocular biometry. RESULTS: There were significant differences between IOL Master and US in the mean error (0.24 +/- 0.63 vs. 0.69 +/- 0.64 dpt, p < 0.001) and the mean absolute error (0.57 +/- 0.36 vs. 0.79 +/- 0.53 dpt, p < 0.001). The cataract density was significantly correlated with the prediction error with IOL Master (r = 0.24, p = 0.03) and US (r = 0.29, p = 0.01). CONCLUSIONS: Measurements with the IOL Master are slightly affected by the cataract density due to the refractive index change, but its accuracy is less affected than US.

Frequency doubling technology perimetry after clear and yellow intraocular lens implantation.

PURPOSE: To evaluate the effect of intraocular lens (IOL) color on frequency doubling technology (FDT). DESIGN: Randomized clinical trial. METHODS: For 26 eyes of 26 patients, FDT perimetry (24-2-threshold test) was measured three months after cataract surgery. An acrylic IOL was randomly selected from clear (VA60BB, HOYA) and yellow-tinted lenses (YA60BB, HOYA), which only differed by color. As a control, a further 14 cataractous eyes with visual acuity > or =20/30 were examined. We analyzed mean deviation (MD) and pattern standard deviation (PSD) among the three groups. RESULTS: After cataract surgery, MD significantly improved (Fisher protected least significant difference (PLSD): P < .05), but PSD did not change (analysis of variance (ANOVA): P = .94) compared with control values. There was no significant difference between the two IOLs for either MD (Mann-Whitney test; P = .15) or PSD (Mann-Whitney test; P = .84). CONCLUSIONS: When interpreting the results of FDT, the effect of cataract should be considered but that of IOL color does not need consideration.