Sensorial status in patients with pure accomodative esotropia. / Binocularidad en pacientes con endotropía totalmente acomodativa.

OBJECTIVE: To evaluate the sensorial status in patients with pure accommodative esotropia. MATERIAL AND METHODS: Ambispective study, patients with pure accommodative esotropia that were found in orthotropy when using its correction glasses were included. RESULTS: 67 patients were included, mean age was 3.68±1.28 years, the near and far ocular deviation was 19±8.8 PD and 18.71±10.61 PD respectively. The visual acuity in the right eye was 0.183 ±0.11 logMAR, in the left eye was 0.188±0.12 logMAR. The average spherical equivalent was +5.50 diopters, for the right eye was +5.46 ±1.61 diopters and for the left eye +5.71 v±1.6 diopters. The average AC/A ratio was 5.19±0.92 Δ/1. 90% of the patients had a grade of near stereopsis: 42% had stereopsis equal or better to 70 arc seconds and 81% had stereopsis equal or better to 400 arc seconds, having an average of 205 arc seconds. 85% of the patients had some grade of far stereopsis: 16% had stereopsis equal or better to 70 arc seconds and 66% had a stereopsis equal or better to 400 arc seconds, having an average of 334.9 arc seconds. There was not statistically significant correlation between the grade of deviation and the stereopsis when using its correction. CONCLUSIONS: This study has detected that the sensorial status is compromised even with adequate and appropriate treatment, nevertheless, there is a low frequency of amblyopia.

Botulinum toxin type A as treatment of partially accommodative esotropia.

OBJECTIVE: To determine the effectiveness of a botulinum toxin type A injection in both medial rectus muscles in patients with partially accommodative esotropia. Residual deviation and stability of strabismus were evaluated at 18 months follow up. METHOD: A prospective, analytical, quasi-experimental study was conducted on a cohort of 21 patients who underwent total cycloplegic refraction and with a residual deviation of at least 14 DP. A botulinum toxin type A dose of 5 IU was injected into each medial rectus muscle for a residual deviation greater than 18 DP, with a dose of 2.5 IU being used for a deviation between 14 and 18 DP. Multivariate logistic regression analyses were performed to relate residual deviation to variables recorded as potential predictors. RESULTS: A total of 21 patients were included, 33.3% (n=7) males and 66.6% (n=14) females. Mean visual acuity was -.28±.25 logMAR for right eye (range 0 to -1) and -.42±.31 logMAR for left eye (range 0 to -1.3). Mean angle of residual deviation before application of botulinum toxin was 40.95±8.6DP without spectacles correction, and 22.3±7.99 DP with full cycloplegic refraction. Adverse effects were ptosis in 14.2% (n=3), diplopia 23.8% (n=5), and vertical deviation in 33% (n=7). One patient had a poor outcome, therefore required surgical treatment. At one year follow up, 85.71% of patients showed good results with esotropia of 12 DP or less, dropping to 71.43% at 18 months of follow up. CONCLUSION: Botulinum toxin type A is an effective long-term treatment with a good response in 71.43% of patients. No predictors of good response were demonstrated.

Adiabatic formation of quasibound states of antihydrogen.

The classical trajectory of an initially unbound positron within the electric field of an antiproton and a uniform magnetic field is simulated in three dimensions. Several simulations are run incorporating experimental parameters used for antihydrogen production, which has been achieved by two different groups [M. Amoretti, Nature (London) 419, 456 (2002); G. Gabrielse, Phys. Rev. Lett. 89, 213401 (2002)]. The simulations indicate that temporary bound states of antihydrogen can form at positive energies, where the energy of the system is defined to be zero when the positron and antiproton are at rest with infinite separation. Such quasibound states, which form only when the magnetic field is present, are typically smaller than in a dimension perpendicular to the magnetic field. An analytical model is developed for a formation cross section, and it is found that quasibound states may form more frequently than stable Rydberg states.

Relationship between corn vitreousness and ruminal in situ starch degradability.

The objective of this experiment was to determine the relationship between corn kernel vitreousness and ruminal in situ starch degradation. Fourteen U.S. and five Brazilian corn hybrids cultivated in their respective countries were evaluated. The U.S. dent hybrids were harvested at one-half milk line, black layer, and 21 d after black layer stages of maturity. Brazilian flint hybrids were harvested only at the latest stage of maturity. Vitreousness was determined by manual dissection of the kernels. Ruminal in situ degradation of starch was determined in three lactating Holstein cows fitted with ruminal cannulae. Vitreousness of the five mature Brazilian hybrids averaged 73.1% (range of 64.2% to 80.0%), while vitreousness of the 14 mature U.S. hybrids averaged 48.2% (range of 34.9% to 62.3%). Within the 14 U.S. hybrids, average vitreousness increased from 42.8% to 48.2% as stage of maturity progressed from one-half milk line to 21 d after black layer. The correlation between kernel density and vitreousness was 0.87. The correlations between kernel vitreousness or density and ruminal starch availability were -0.93 and -0.87, respectively. With advancing maturity, kernel vitreousness and density increased while ruminal starch availability decreased. Kernel vitreousness and density may be useful parameters for which to select corn hybrids for high ruminal starch availability. Density may be a more practical measurement than vitreousness for screening large corn data sets.