Accuracy of intraocular lens (IOL) calculation formulas SRK/T, Hoffer Q, Holladay 1, Haigis and Barrett Universal II were compared in prediction of postoperative refraction for multifocal and implants using a single optical biometry device. The authors included 88 refractive lens exchange and cataract surgeries, with AcrySof IQ PanOptix implant (Alcon Laboratories, Inc.). All eyes were divided into three groups based on axial length (AL), group 1: <22 mm (14 eyes), group 2: 22-24.5 mm (68 eyes) and group 3: >24.5 mm (6 eyes). The refractive prediction error (RPE) and mean absolute error (MAE) were calculated for 5 different formulas: SRK/T, Hoffer Q, Holladay 1, Haigis and Barrett Universal II. For eyes with the AL between 22 mm and 24.5 mm the greatest percentage of eyes with RPEs within ±0.25 D was 32.4% for Haigis formula, followed by Barrett Universal II, Hoffer Q and Holladay 1 with 29.4%. The percentage of eyes with RPEs within ±0.50 D was 100% only for Barrett Universal II and Holladay 1, 94.1% for SRK/T and 91.2% for Haigis and Hoffer Q. The first and third group with AL <22 and >24.5 mm were too small to have statistical significance due to the reluctancy to use multifocal IOLs on extreme ALs. ANOVA test showed no statistical difference (P=0.166) between the RPEs measured for each formula in this cohort. This study showed no statistical difference between formulas for this trifocal lens implant. There was a tendency for the RPE to be within ±0.25 D for most of the eyes with the Haigis formula, and within ±0.50 D for all the eyes with the Barrett Universal II formula in the group with the AL between 22 and 24.5 mm.

Cumulative visual impact of two coagulability disorders were reviewed by presenting a case of a young female patient with a spontaneous abortion and two thromboembolic events in 8 years, whose visual function was severely affected. The particularities of her genetic constellation regarding the retinal circulation are also discussed. The patient developed a central retinal artery occlusion in the right eye during pregnancy in 2010, which led to an extended hematological workup that revealed presence of MTHFR C677T and MTHFR A1298C heterozygote mutations. The screening for myeloproliferative disorders showed JAK2 V617F gene mutation. Test results confirmed the diagnosis of thrombophilia and essential thrombocythemia and she was recommended permanent treatment with low molecular weight heparin, platelet antiaggregant, peripheral vasodilator and neuroprotectors. Despite the treatment, the patient developed central retinal vein occlusion in the fellow eye 8 years after the first thromboembolic event. The visual acuity for the right eye (0.9 logMAR) remained poor and the visual acuity for the left eye recovered completely (from 0.3 logMAR to 0 logMAR). However, new retinal artery or vein occlusions could occur in the future and there is also a risk of thrombosis in other areas, such as cerebral, pulmonary or renal, due to the general coagulability imbalance.

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We present a case of Bilateral Central Retinal Vein Occlusion in a patient who received 11 dental implants and later developed idiopathic glomerulonephritis with renal failure.

The present study aimed to compare the accuracy of intraocular lens calculation formulas Barrett Universal II, Hoffer Q, Holladay 1, and SRK/T in the prediction of postoperative refraction for two widely used monofocal implants: SN60WF and ZCB00. All eyes were divided based on axial length (<22 mm, 22–24.5 mm, and >24.5 mm) and lens type. The mean and median of the absolute refractive error (AE) were calculated for all four formulas, using manufacturer-recommended lens constants as well as optimized constants. The subgroup analysis showed that the Barrett Universal II formula had the smallest mean absolute error in three groups (with short, medium, and long axial length) before and after lens factor optimization, and Holladay 1 had the best results in two groups (of medium and long axial length), and SRK/T in one short axial length group, as well as one medium AL group after A-constant optimization. This study hints at the versatility of the Barrett Universal II formula, a fourth-generation formula that is now widely available on most optical biometers and provides a useful tool of calculation for eyes of all axial lengths even without lens constant optimization.