The Investigation With Contrast Sensitivity And Glare Sensitivity After Implantation With Blue Light Filtering And Non-blue Light Filtering Type Of Intraocular Lens

ObjectiveTo measure the contrast sensitivity and glare sensitivity of patients who underwent phacoemulsification and implantation of blue light filtering IOL and compare the result with those of implantation of non- blue light filtering IOL , to evaluate that whether blue light filtering IOL is superior to non- blue light filtering IOL in the visual function, providing basis for choosing intraocular lens.Materials and methodsAll 52 cases (66 eyes) were recruited from cataract patient diagnosed from jul.2004 to Feb. 2005. There were 28 males (34 eyes), 24 females (32 eyes), aged 66.5 (55 to79yrs). The patients were divided into two groups at random, the blue light filtering IOL group: 30 cases (36 eyes), 16 males and 14 females, with average age of 66.2 yrs; 36 eyes implanted with blue light filtering IOLs; the non- blue lighting IOL group: 22 cases (30 eyes), 12 males and 10 females, average age 67.1 years old. 30 eyes implanted with no-blue light filtering IOLs. In addition, 19 volunteers wererecruited as controls group, 30 eyes (natural crystals), age range 55 to 79, 9 males and 10 females. The control group matches with the 2 IOL groups in the age. The patients was excluded with any other eye diseases, all patient have no systemic disease such as diabetes mellitus, hypertension, rheumatism. Visual acuity, best correct visual acuity, contrast sensitivity and glare sensitivity were measured before and after the implantation. All surgeries were done by one surgeon and with no complication. The contrast sensitivity and the glare sensitivity were measured withTakaci-CGT-1000 automatically to dazzle and contrast sensitivity tester 10-15 days after surgery. The best correct visual acuity of all patients after the cataract surgery were measured, x2 test and the q test were used for statistical analysis. Probability of less than 0.05 was considered significant.ResultsThe best correct visual acuity of all patients after the cataract surgery were better than 0.8. There was no significant difference between the two IOL groups for the best correct visual acuity (x =0.115; />=0.998). The contrast sensitivity and the glare sensitivity of all patients were improved remarkably at different visual angles. At high luminance level, the difference among groups for contrast sensitivity and glare sensitivity was statistically significant for all visual angles (p<0.05). The blue light filtering IOL -implanted eyes had better results compared to non- blue light filtering IOL—implanted eyes at all visual angles, Significant difference existed between the two IOL groups in CSF and GSF of all visual angle (p<0.05), especially , it is more remarkable at 2.5°--1.6°(p < 0.01). CSF and GSF scores were significantly higher in the blue light filtering IOL group compared to the non- blue light filtering IOL. There was no significant difference of contrast sensitivity function in the blue light filtering group compare to controls at 6.3°~1.6°visual angles (p>0.05). Significant difference existed at 1.0°-0.7°visual angle (p< 0.01). CSF of the blue light group is significantly lower than that of control. There was significant difference between the blue light group and the control groups in glare sensitivity at 2.5 ° -0.7° visual angle (p< 0.01), GSF of the blue light group is significantly lower than that of control. Significant difference existed between the non- blue light group and the control groups in CSF and GSF of all visual angles (p<0.01) ConclusionsPhacoemulsification and intraocular lens implantation is an ideal procedure for cataract. The visual acuity has improved remarkably in all patients after implanting blue light filtering IOL or non- blue lighting IOL. The different type of IOL has certain influence on the visual function. The blue light filtering IOL blocks the ultraviolet rays and the blue light then reduced the scatter of light and the harm to theretinal resulting from ultraviolet ray and the blue light. The visual quality achieved in the intraocular lens eyes was not as good as in natural crystal eye eyes in regard to contrast sensitivity and glare sensitivity. Contrast sensitivity function and glare sensitivity function have the remarkable improvement after phacoemulsification and implantation of different type intraocular lens. Blue light filtering IOLs were better than non- blue light filtering IOLs.