Retinal nerve fiber layer thickness was found to be unaffected in migraine patients.

Brinzolamide may cause a short-term increase in the human CCT, particularly on the first day.

This is the first report suggesting normal thickness of the RNFL in subjects with congenital red-green CVD.

Although all the results presented were statistically insignificant, switching to latanoprost treatment may offer some advantages in respiratory and cardiovascular function for elderly people with glaucoma over beta-blocker drugs. Spirometry and the measurement of pulse rate and blood pressure are advised in all patients receiving topical beta-blocker therapy.

Several formulas to calculate the refractive power for intraocular lens (IOL) implantation are available. Various biometers are on the market for this purpose with built-in programs to directly perform the necessary calculations; eg, the IOLMaster (Carl Zeiss Meditec). It is for the surgeon to decide which instrument and what formula to use to obtain the most appropriate IOL power for his or her patient.Comparing the IOL power results of the Hoffer Q formula 1,2 for an emmetropic, myopic, and hyperopic eye calculated first with the original (corrected 2 ) Hoffer Q formula and then with the IOLMaster versions 4.02 and 5.02, we found deviations from the results as shown in Table 1. No deviations were found when the IOLMaster's corneal index of refraction (IR) was adjusted to 1.3375 instead of the originally published 1.336. This probably means that the Hoffer Q formula in the IOLMaster 4.02/5.02 uses a corneal index of refraction of 1.3375, deviating from the original Hoffer Q formula, 1 and hence from other machines, and resulting in a 0.25 diopter difference in IOL power. In the United States, the IOLMaster's IR is routinely set at 1.3375. However, in the European Union, it is set at 1.336 to match the IR used by manual keratometers in the EU. Therefore, to obtain accurate results for the Hoffer Q with the IOLMaster, the IR has to be changed manually to 1.3375.Although the clinical significance of this finding might be negligible, the information might be of interest to anyone comparing the Hoffer Q formula calculations of various biometers and of the IOLMaster. CORRESPONDENCE J CATARACT REFRACT SURG -VOL 34, NOVEMBER 2008