SETTING: Department of Ophthalmology, Gloucestershire Hospitals NHS Foundation Trust, Cheltenham, United Kingdom.
DESIGN: Database study.
METHODS: Hypothetical prediction errors were retrospectively calculated on prospectively collected data extracted from electronic medical records using manufacturers’ and optimized IOL constants with
Hoffer 3-Methyladenine price Q, Holladay 1, and SRK/T formulas for 2 IOLs. The acceptable IOL-constant optimization error margins, personalized IOL constants for individual surgeons, and minimum sample sizes for IOL-constant optimization were evaluated.
RESULTS: Optimization of IOL constants reduced the mean absolute errors from 0.66 diopters (D) and 0.52 D to 0.40 D and 0.42 D for the Sofport AO IOL and Akreos Fit IOL, respectively. The
percentage of eyes within +/- 0.25 D, +/- 0.50 D, and +/- 1.00 D of target refraction improved from for both IOL models. The IOL-constant errors exceeding 0.09 for the Hoffer Q, 0.09 for the Holladay 1, and 0.15 for the SRK/T produced inferior outcomes. Differences in personalized IOL constants between most surgeons were clinically insignificant. Calculating IOL constants to within 0.06, 0.06, and 0.10 for the Hoffer Q, Holladay 1, and SRK/T, respectively, required 148 to 257 eyes.
CONCLUSIONS: Optimizing IOL constants for IOLMaster biometry substantially improved refractive outcomes, far exceeding any additional benefit of personalizing IOL constants for individual surgeons.”
“2,7-di-tert-butylpyrene was oxidized to 2,7-di-tert-butylpyrene-4,5,9,10-tetraone. The latter through condensation reactions with vicinal C59 diamine such as 4,5-diaminophthalonitrile produced heterocyclic monomer, 2,7-di-tert-butyl pyrene[4,5][9,10]bisquinoxaline-6,7-dinitrile,
which was cyclo-tetramerized to the corresponding tetra[2,3-(1,4-diaza-6,6-di-tert-butylphenanthreno)[4,5]phthalocyanine]-based network polymer (2H-Pc), and tetra [2,3-(1,4-diaza-6,6-di-tert-butylphenanthreno)[4,5]phthalo-cyaninato metal II-based network polymers (M-Pc, M= Co, Ni, Zn, or Cu). Elemental analytical results, IR and NMR spectral data of the new prepared molecules are consistent with their assigned formulations. Molecular masses and metal contents Selleckchem ZD1839 of the synthesized polymers proved to be of high molecular masses which confirm the efficiency of tetramerization polymerization and complexation reactions. The dielectric constant (epsilon’) and dielectric loss tangent (tan delta) were studied as a function of temperature and frequency. The detailed analysis of the results showed that the dielectric dispersion consists of both dipolar and interfacial polarization. Measurements of ac conductivity as a function of frequency at different temperatures revealed that the nonoverlapping small polaron tunneling is the most suitable mechanism for ac conduction behavior. (C) 2011 Wiley Periodicals, Inc.