Analysis of the optical quality of intraocular lenses.

PURPOSE. To evaluate the optical quality of different intraocular lenses (IOLs). METHODS. An optical test bench and suitable software were used to assist in analysis of the optical Fourier transform (OFT) of a test image and to determine the quality of the lens in terms of spatial frequency response. The OFT was automatically converted, by means of an optical– electronic calibration procedure, into a modulation transfer function (MTF) for each lens. The passband value calculated by computer analysis of the MTF is an objective index of the lens quality. Three randomly acquired samples of 24 different models of foldable IOLs were compared. Statistical analysis was performed with twoway and one-way ANOVA for repeated measurements and with the Ryan-Einot-Gabriel-Welsch multiple F test. RESULTS. The method was demonstrated to be precise and accurate. A large range of passband values was found. Statistically significant differences between the mean passband values for different lenses were found. The lowest passband value (125.60 line pairs [lp]/mm) was measured for the IOL (Lenstec LH3000; Lenstec, Inc., St. Petersburg, FL) and the highest (191.48 lp/mm) for the Acrysof SA30AL (Alcon, Fort Worth, TX). CONCLUSIONS. Different IOLs can transmit different spectra of spatial frequencies. The best frequency response was provided by acrylic IOLs, particularly those with an asymmetrically biconvex profile. This could be due to a reduction of optical degradation provided by this type of profile. A lens with a higher frequency response should determine a better quality of vision once implanted and the frequency response should therefore be considered when choosing the intraocular lens model. (Invest Ophthalmol Vis Sci. 2004;45:2682–2690) DOI: 10.1167/iovs.03-102

-Dual nucleoside therapy for HIV infection: analysis of results and factors influencing viral response and long term efficacy.

We performed a retrospective analysis of our experience with dual nucleoside regimens to look for predictors of long term benefit. We evaluated a cohort of 68 HIV-infected patients treated at 3 Italian hospital-based facilities. The results were analysed using univariate and multivariate statistical analyses. Fourty-three males and 25 females were treated for 22 ± 14 months. Sixty three patients (92.6%) suffered no or low-grade side-effects. Thirty-four patients (50 %) reached a viral load 150/μl pre-treatment viremia 1,500/μl, and no previous exposure to NRTI. Total lymphocyte counts and CD4+ T-cells showed a significant correlation. Dual NRTI regimens may be still considered for patients unable to tolerate HAART regimens and presenting with favourable predictors of response

LA DIMENSIONE CAMPIONARIA NELLA VERIFICA DI IPOTESI STATISTICHE

missin

CONSIDERAZIONI SULL’INFERENZA STATISTICA E LA VERIFICA DI IPOTESI

MISSIN

Nickel oral hyposensitization in patients with systemic nickel allergy syndrome

Background: This is the fi rst randomized, double-blind, placebo- controlled trial (EUDRACT No. 2009-013923-43) evaluating nickel oral hyposensitizing treatment (NiOHT) in patients with \u201c systemic nickel allergy syndrome \u201d (SNAS), characterized by Niallergic contact dermatitis and systemic reactions after eating Ni-rich food. Methods: Adults with positive Ni-patch test, who reported symptoms suggesting SNAS, which improved after Ni-poor diet, and were positive to Ni-oral challenge were eligible. Patients were randomly assigned to three treatments (1.5 g, 0.3 g, or 30 ng Ni/week) or placebo for a year, with progressive reintroduction of Ni-rich foods form the 5 th month. Out of 141 patients randomized, 113 completed the trial. Endpoints were effi cacy and tolerability of treatment. Results: During Ni-rich food re-introduction, the 1.5 g Ni/week group had a mean VAS score signifi cantly higher than placebo (p 0.044), with signifi cant improvement of gastrointestinal symptoms (p 0.016;) and signifi cantly fewer rescue medications. Cutaneous manifestations also improved but without reaching statistical signifi cance. After the treatment, oral challenge with higher Ni doses than at baseline were needed to cause symptoms to fl are-up in signifi cantly more patients given 1.5 g Ni/week than placebo (p 0.05). Patients reported no side-eff ects. Conclusions: NiOHT is eff ective in SNAS, in particular on gastrointestinal manifestations, with trend toward improvement of cutaneous symptoms