1,720,971 research outputs found
Measurement of retinal nerve fiber layer thickness, macular thickness, and foveal volume in amblyopic eyes using spectral-domain optical coherence tomography.
No full textAlthough the changes in the anatomy of the visual cortex and lateral geniculate nucleus as the result of amblyopia have been well documented, retinal involvement is still controversial. Time-domain optical coherence tomography with an axial resolution of 10 μm has been used to evaluate retinal and peripapillary tissues in amblyopic eyes with contradictory results. Spectral domain optical coherence tomography has a greater resolution (5-10 μm) and can determine retinal layers more precisely. Our purpose was assess by means of spectral domain optical coherence tomography whether the retinal nerve fiber layer thickness, macular thickness, and foveal volume of the amblyopic and the fellow eyes differ in patients with unilateral amblyopia. Intereye differences in these parameters were found to be insignificant
The role of ocular oscillations upon visually dependent postural stabilization in patients affected by congenital nystagmus.
No full textVisually dependent postural stabilization decreases as a consequence of a long-standing reduction of visual cues in patients affected by congenital nystagmus. The aim of the present study was to verify whether the changes in postural control in this group of patients are due to ocular oscillations or to reduced visual acuity. Therefore, postural control was evaluated when the nystagmus was blocked by the blocking position or by prisms and compared with the postural score observed in a group of normal controls whose visual acuity had been artificially reduced to the same level as that of the patients using Bangerter's filters. The results show a statistically significant improvement of visually dependent postural stabilization when ocular oscillations are inhibited either by the gaze blocking position or by prisms. They also show that postural control in normal subjects with Bangerter's filters is reduced, but is still significantly better than that observed when ocular oscillations are inhibited in patients affected by congenital nystagmus. Our data strongly support the role of ocular oscillations in visually dependent postural control, since postural impairment recovered under any condition in which ocular oscillations were abolished, despite differences in visual acuity. Our data also show that reduced visual acuity decreases visually dependent postural control to a lesser degree than ocular oscillations. This could be due to the fact that ocular oscillations are a disturbing input, usually inhibited centrally, in order to avoid oscillopsia. This mechanism is probably responsible for the reduced role of visual cues in the postural control in this group of patients. The reduction of visual acuity, by comparison, merely causes a decrease in visual cues, depending on the degree of visual loss. It can be concluded that the impaired postural control in patients affected by congenital nystagmus is mainly due to ocular oscillations, with reduced visual acuity creating a secondary effect
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Acute acquired concomitant esotropia and decompensated monofixation syndrome: a sensory-motor status assessment
No full textPurpose: To assess and compare sensory-motor status and clinical features of type I and type II Purpose: To assess and compare sensory-motor status and clinical features of type I and type II acute acquired concomitant esotropia (group A) and decompensated monofixation syndrome (group B).
Methods: In a retrospective, comparative study twenty-six patients, with a confirmed postoperative diagnosis of types I and II acute acquired concomitant esotropia and monofixation syndrome, were enrolled. A two-tailed unpaired t-test and a two-tailed chi-square test were performed to compare angle deviation and sensory-motor status under viewing conditions and after prismatic adaptation test and progressive prism test of two groups.
Results: All of the patients of group A and 4 patients (33%) of group B complained of diplopia under viewing conditions, at the Worth’s 4 dot and Bagolini striated glasses test. The TNO stereo test showed the total absence of stereopsis in 6 patients in group B and a significantly lower stereoacuity in group A in the remaining six patients (p<0.0001). The Prismatic adaptation test was positive in all of the patients in group B and in 10 patients (71%) in group A (p=0.39). The value of the angle deviation after progressive prism test was significantly higher in group B than group A (p = 0.02). At the end of the progressive prism test all of the patients in group A and only two patients in group B were orthotropic (p=0.01).
Conclusions: Bagolini striated glasses and Worth’s 4 dot tests under viewing conditions, and responses under prisms allow for the differentiation of the two forms and lead to an accurate aesthetic and functional prognosis.
Keywords: acute acquired concomitant esotropia, decompensated monofixation syndrome, prismatic adaptation test, strabismus, diplopia
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
A Modified One-Stage Early Correction of Blepharophimosis Syndrome Using Tutopatch Slings
No full textPURPOSE:To investigate the efficacy of a one-stage early correction of blepharophimosis-ptosis-epicanthus inversus syndrome (BPES), using bovine pericardium derived membrane (TUTOPATCH(®)) for the frontalis suspension.
METHODS:We prospectively studied 12 eyes from 6 patients (median age 14 months) affected by BPES with severe ptosis. All patients were submitted to a one-stage early correction of ptosis (frontalis suspension with TUTOPACH(®)) and telecanthus and epicanthus inversus. Upper margin reflex distance (MRD), nasal inner intercanthal distance (IICD), horizontal fissure length (HFL), and IICD/HFL ratio were evaluated using photographs.
RESULTS:The Wilcoxon signed-rank test showed a statistically significant difference between pre- and post-operative MRD, IICD, HFL, and the IICD/HFL ratio.
CONCLUSION:An early TUTOPATCH-assisted frontalis suspension, together with the correction of telecanthus and epicanthus inversus, is an effective procedure for BPES cases with severe ptosis
- …
