The Binocular Visual System in Amblyopia

We treated a 27-year-old man who suffered from a congenital eye movement abnormality. The patient could not adduct the left eye, and showed exotropia, hypertropia and excyclotropia of the left eye. The range of abduction was also limited. The left eye showed marked upshoot on right gaze and eye globe retraction on right down gaze under conditions of right-eye viewing.The superior rectus muscle of the left eye was recessed and transposed nasally.The insertion of the superior oblique muscle was found to be defective. The upshoot and face turn improved after surgery. The globe retraction on right down gaze was no longer evident.We believe that the superior rectus muscle was innervated by an anomalous branch of the oculomotor nerve, which was originally destined to innervate the medial rectus, and that simultaneous contraction of the superior and inferior rectus muscles caused the globe retraction on right down gaze.This case also suggests the possibility that some part of the upshoot in adduction in Duane's syndrome is due to the co-contraction of the superior and medial rectus muscles due to this innervation anomaly.     

Naso-temporal asymmetries in human amblyopia: Consequence of long-term interocular suppression

The resolution for vertical gratings was tested at different eccentricities in the visual field of 9 strabismic and 2 anisometric amblyopes.It has been found that, within the central 20° of the visual field of esotropic amblyopes, the acuity of the nasal retina was much more reduced than that of the temporal retina. Outside this region, acuity was practically identical to that of the non-amblyopic eye. This asymmetric loss of acuity was well correlated with the interocular suppression as determined by a method of interocular perimetry.For anisometropic amblyopes, the acuity loss was symmetric, diminishing gradually towards the periphery. The interocular suppression was also symmetric, uniformly affecting all tested positions in the visual field of the amblyopic eye.     

Design of poly-epsilon-caprolactone nanospheres coated with bioadhesive hyaluronic acid for ocular delivery.

This study was performed to design a new ocular drug delivery system based on poly-epsilon-caprolactone (PCL) biodegradable nanospheres (NS) coated with a bioadhesive polymer, hyaluronic acid (HA), in order to combine ophthalmic prolonged action with the ease of application. The aim of this work was to investigate three strategies to attach HA on NS surface: (1) coating the core by chain entanglement with HA; (2) coating NS by HA adsorption; (3) coating NS by electrostatic interactions between negatively charged HA and a cationic surfactant (stearylamine, SA, or benzalkonium chloride, BKC). A radioimmunoassay technique, usually used for HA quantification in serum, was transposed to determine the amount of HA on the NS. The results show that HA is strongly attached on NS positively charged by cationic surfactant. This system is stable and not influenced by dilution. These results show the possibility of using cationic surfactants to obtain a HA coating by electrostatic interactions. BKC, approved for ophthalmic administration, was retained because it was more firmly anchored within the PCL matrix and the amount of HA attached was high (41.6 microg HA/mg PCL). Moreover, the yield of fixation reached 50%. Therefore, by using a simple preparation method, it was possible to obtain stable HA and intact HA-coated NS.     

Topological Features of Electroencephalography are Robust to Re-referencing and Preprocessing

Brain Topography - Electroencephalography (EEG) is among the most widely diffused, inexpensive, and adopted neuroimaging techniques. Nonetheless, EEG requires measurements against a reference...     

Cardiovascular risk factors in patients with spondyloarthritis from Northern European and Mediterranean countries: An ancillary study of the ASAS-COMOSPA project

Objectives

The objectives of this study were: (1) to compare the prevalence of cardiovascular disease and cardiovascular risk factors among different phenotypes of spondyloarthritis (SpA); (2) to assess the differences in cardiovascular disease and cardiovascular risk factors between two geographical areas, i.e. Northern Europe vs. Mediterranean region; (3) to identify potential predictive factors for high Framingham Risk Score regarding disease features in SpA and geographical area.

Evolutionary-driven support vector machines for determining the degree of liver fibrosis in chronic hepatitis C

Objective

Hepatic fibrosis, the principal pointer to the development of a liver disease within chronic hepatitis C, can be measured through several stages. The correct evaluation of its degree, based on recent different non-invasive procedures, is of current major concern. The latest methodology for assessing it is the Fibroscan and the effect of its employment is impressive. However, the complex interaction between its stiffness indicator and the other biochemical and clinical examinations towards a respective degree of liver fibrosis is hard to be manually discovered. In this respect, the novel, well-performing evolutionary-powered support vector machines are proposed towards an automated learning of the relationship between medical attributes and fibrosis levels. The traditional support vector machines have been an often choice for addressing hepatic fibrosis, while the evolutionary option has been validated on many real-world tasks and proven flexibility and good performance.

Methods and materials

The evolutionary approach is simple and direct, resulting from the hybridization of the learning component within support vector machines and the optimization engine of evolutionary algorithms. It discovers the optimal coefficients of surfaces that separate instances of distinct classes. Apart from a detached manner of establishing the fibrosis degree for new cases, a resulting formula also offers insight upon the correspondence between the medical factors and the respective outcome. What is more, a feature selection genetic algorithm can be further embedded into the method structure, in order to dynamically concentrate search only on the most relevant attributes. The data set refers 722 patients with chronic hepatitis C infection and 24 indicators. The five possible degrees of fibrosis range from F0 (no fibrosis) to F4 (cirrhosis).

Results

Since the standard support vector machines are among the most frequently used methods in recent artificial intelligence studies for hepatic fibrosis staging, the evolutionary method is viewed in comparison to the traditional one. The multifaceted discrimination into all five degrees of fibrosis and the slightly less difficult common separation into solely three related stages are both investigated. The resulting performance proves the superiority over the standard support vector classification and the attained formula is helpful in providing an immediate calculation of the liver stage for new cases, while establishing the presence/absence and comprehending the weight of each medical factor with respect to a certain fibrosis level.

Conclusion

The use of the evolutionary technique for fibrosis degree prediction triggers simplicity and offers a direct expression of the influence of dynamically selected indicators on the corresponding stage. Perhaps most importantly, it significantly surpasses the classical support vector machines, which are both widely used and technically sound. All these therefore confirm the promise of the new methodology towards a dependable support within the medical decision-making.     

The Impact of Roux Limb Length on Weight Loss After Gastric Bypass

Background Extending the length of the Roux limb (RL) in gastric bypass (GBP) may improve weight loss in super obese patients (body mass index [BMI] > 50 kg/m²), but no consensus exists about the optimal length of the RL. We sought to determine the impact of RL length on weight loss in super obese patients 1 year after GBP. Materials and Methods One-year weight loss outcomes were analyzed in all super obese patients who underwent consecutive and primary laparoscopic or open GBP between January 2003 and June 2006. Patients were divided into two groups according to RL length (100 vs. 150 cm). The RL length was at the discretion of the attending surgeon. Baseline and follow-up data were collected prospectively. Multiple linear regression was used to adjust for potential confounders in the weight loss outcomes. Results Twelve-month follow-up data were available in 137 (85%) of 161 patients with a BMI ≥ 50 who underwent GBP during the study period. An RL of 100 or 150 cm was used in 102 (74.5%) and 35 patients (25.5%), respectively. In multivariate analysis, patients with the 150-cm RL lost more weight (68.5 vs. 55.3 kg, p < 0.01), had a greater change in BMI (25 vs. 21 kg/m², p = 0.01), and had greater excess weight loss (64 vs. 53%, p < 0.01). Conclusion A 150-cm RL provides better weight loss outcomes in super obese patients at 1-year follow-up.