PURPOSE: To compare the accuracy of intraocular lens (IOL) power calculation in patients with previous radial keratotomy using the Haigis and Barrett True-K formulas. METHODS: In a retrospective cases series of patients with previous radial keratotomy and minimum follow-up of 1.2 months, preoperative data from an IOLMaster 500 or 700 (Carl Zeiss Meditec AG), the IOL power implanted, and the postoperative refraction were used to calculate the refractive prediction error. The primary outcomes were the mean absolute and arithmetic refractive prediction errors and the percentage of eyes with a refractive prediction error within ±0.50 and ±1.00 diopters (D). RESULTS: One hundred eight eyes were evaluated with a mean follow-up of 6.9 ± 4.9 months. The Haigis formula yielded a mean arithmetic refractive prediction error of −0.29 ± 1.00 D, which was significantly different than that of the Barrett True-K formula, which was −0.03 ± 0.96 D ( P < .001). The mean absolute refractive prediction error was 0.80 ± 0.67 for the Haigis formula and 0.74 ± 0.60 for the Barrett True-K formula ( P > .05). The percentages of eyes with a refractive prediction error within ±0.50 and ±1.00 D were 43.5% and 65.7% for the Haigis formula and 42.6% and 75.9% for the Barrett True-K formula, respectively (all P > .05). The subgroup analysis revealed that for flat corneas (K1 < 38.00 D), the Barrett True-K formula resulted in more hyperopic results than the Haigis formula. CONCLUSIONS: The Barrett True-K formula exhibited better arithmetic predictability than the Haigis formula; however, it showed a tendency for hyperopic results in very flat corneas. [ J Refract Surg . 2020;36(12):832–837.]

BackgroundCataract is the leading cause of blindness in developing countries and identification of the barriers to accessing treatment is essential for developing appropriate public healthcare interventions. To evaluate the barriers to cataract surgery after diagnosis and assess the postoperative outcomes in Sao Paolo State, Brazil.MethodsThis prospective study evaluated cataract patients from 13 counties in São Paulo State in 2014. Cataract was diagnosed in the community by a mobile ophthalmic unit and patients were referred to a hospital for management. Gender, age, distance to the hospital and local municipal health structure were evaluated as possible barriers. Data were analyzed for postoperative outcomes and the impact on blindness and visual impairment.ResultsSix hundred patients were diagnosed with cataract with a mean age of 68.8±10.3 years and 374 (62.3%) were females. Two hundred and fifty-four (42.3%) patients presented to the referral hospital. One hundred forty-four (56.7%) underwent surgery, 56 (22.0%) decided not to undergo surgery, 40 (15.7%) required only YAG-Laser and 14 (5.5%) required a spectacle prescription only. Visual acuity increased statistically significantly from 1.07±0.73 logMAR at presentation to 0.25±0.41 logMAR at the final visit after intraocular lens implantation (p=0.000). There was a statistically significantly decrease from 17 (11.8%) blind patients and 55 (38.2%) visually impaired patients at presentation to 2 (1.4%) and 5 (3.5%) patients respectively after treatment (p=0.000).ConclusionLess than half of the individuals with cataract presented to the hospital for surgery. Among the patients who underwent treatment, there was an overall decrease in the number of blind individuals and visually impaired individuals. The barriers to cataract surgery were older age, greater distance to the hospital, municipalities with fewer inhabitants and less ophthalmic services.

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OBJECTIVE To evaluate the effectiveness of mobile ophthalmic unit screenings and to investigate barriers between community care and resolution of the problem at a tertiary center.METHODS This prospective study evaluated a convenience sample from 10 municipalities in São Paulo State, Brazil. Patients were assessed in the municipality by a mobile ophthalmic unit and underwent a complete ophthalmic consultation. Patients were referred as warranted to a tertiary hospital.RESULTS The mobile ophthalmic unit screened 1,928 individuals and 714 (37%) were referred. The mean age of the referred patients was 57.12 (SD = 19.5) years with best corrected visual acuity of 0.37 (SD = 0.36) logMAR. Forty-seven (6.6%) patients were blind and 185 (26.5%) were visually impaired. Cataracts (44.7%) and pterygium (14.7%) accounted for most referrals. Of those referred, 67.1% presented to the tertiary center. The diagnosis by the mobile ophthalmic unit corresponded to the one by the tertiary center in 88.5% of the cases. There were a significantly higher number of blind and visually impaired persons among those who presented to the hospital. There was a significantly greater attendance among patients living in more distant municipalities from the reference center with a higher number of inhabitants and a greater number of ophthalmologists in the cities of origin (p < 0.05, all comparisons). Complete treatment was performed in 65.6% of patients, and loss to follow-up was the main cause of incomplete treatment in 50.7% of patients. A total of 313 cataract surgeries were performed, which reduced the number of blind patients from 20 to 2 and of visually impaired individuals from 87 to 2 (p < 0.001).CONCLUSIONS Only 37% of the patients assessed by a mobile ophthalmic unit required referral to a tertiary hospital. Among the referred patients, 67.1% presented to the hospital, and complete resolution after treatment was approximately 65.5%. There was a significant improvement in visual acuity and a reduction in the prevalence of blindness and visual impairment postoperatively.

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