1,721,008 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Necrotizing scleritis after pterygium excision with fibrin glue-fixated conjunctival autograft in Behcet's disease
No full textRecurrence After Primary Pterygium Excision: Amniotic Membrane Transplantation with Fibrin Glue Versus Conjunctival Autograft with Fibrin Glue
No full textPurpose: The aim of the present study was to compare the surgical results and recurrence rates of primary pterygium excision with conjunctival autografts versus amniotic membrane grafts fixated with fibrin glue.Materials and methods: In this prospective study, 73 eyes of 65 patients who had undergone conjunctival autograft group (CAG) (n:37) or amniotic membrane group (AMG) (n:36) after pterygium excision were evaluated. Fibrin glue was used for the fixation of grafts in both groups. The patients were followed up for 12 months. Postoperative complications were recorded. The rate of recurrence was defined as the primary outcome measure.Results: In the CAG, partial dehiscence of the graft was observed on the nasal edge on postoperative day 1 in two (5.4%) eyes that healed with secondary re-epithelialization at week 1. Twelve (32.4%) eyes showed a yellowish-orange or hemorrhagic edema of the graft on postoperative day 7 that spontaneously resolved in 1 to 3 weeks. In the AMG, partial dehiscence and folding of the amniotic membrane occurred in two (5.5%) eyes. Two eyes (5.4 %) in the CAG developed corneal recurrence and five eyes (13.8%) in the amniotic membrane graft group developed recurrence; one limbal (2.7%), four corneal recurrences (11.1%) (p=0.25).Conclusion: Fibrin glue is a safe and effective method for attaching conjunctival or amniotic membrane grafts for wound closure following pterygium surgery. Although the results were not statistically significant, amniotic membrane grafting using fibrin glue seems to have a higher pterygium recurrence rate compared with conjunctival autografting
Tear Cytokine Levels in Vernal Keratoconjunctivitis: The Effect of Topical 0.05% Cyclosporine A Therapy
No full textPurpose: The aims of this study were to evaluate the efficacy of topical 0.05% cyclosporine A on clinical signs and symptoms of vernal keratoconjunctivitis (VKC) and to examine its effect on tear cytokine levels. Methods: Twenty-one patients with active VKC and 15 healthy volunteers were included. Patients were treated with topical 0.05% cyclosporine A. Symptoms and signs were scored on the day of enrollment and at the end of month 1 and month 3. Tear and serum samples were collected before and on the third month of treatment. Interleukin (IL)-2, soluble IL-2 receptor (sIL-2R), IL-3, IL-4, IL-5, IL-6, IL-9, IL-13, IL-17, eotaxin, tumor necrosis factor alpha (TNF-alpha), and interferon gamma (IFN-gamma) in cell-free tear and serum supernatants were measured by multiplex bead analysis. Results: At the end of month 1 and month 3 with topical 0.05% cyclosporine A treatment, statistically a significant decrease was observed in sign and symptom scores of the patients (P < 0.0001). Tear IL-2, sIL-2R, IL-9, IL-17, IFN-gamma, and eotaxin levels in VKC patients were significantly higher than those in controls (P < 0.05). IL-3, IL-4, IL-5, and TNF alpha levels tended to be higher in VKC patients. There was also statistically significant reduction from before 0.05% cyclosporine A treatment to after treatment in tear levels of IL-4, IL-5, IL-17A, TNF alpha, IFN-gamma, and eotaxin (P < 0.05). IL-2 and sIL-2R levels tended to be lower than pretreatment levels. Conclusions: Topical 0.05% cyclosporine A is effective in alleviating signs and symptoms of VKC patients and shows its effect probably by decreasing the local production of some inflammatory mediators in tears
A Novel scoring system for distinguishing keratoconus from normal eyes
No full textPurpose: To evaluate the accuracy of a novel scoring system in differentiation of keratoconus (KC) eyes from normal eyes using a Scheimpflug camera system tomography. Setting: Marmara University Hospital, Istanbul, Turkey and Birinci Eye Hospital, Istanbul, Turkey. Design: Retrospective case-control study. Methods: The study included 624 keratoconus eyes and 512 healthy eyes. Thirty nine significant parameters obtained from the Scheimpflug imaging system (Pentacam-Oculus Optikgerate GmbH, Wetzlar, Germany) were studied. The cut-off value and area under receiver operating characteristic (AUROC) curve analysis for each studied parameter were established in the previous study. Minus three and plus three standard deviations of the cut-off value were scored after multiplication of AUROC for each parameter. The sum of all scores (TKS; Total Keratoconus Score) was compared between keratoconus and normal eyes. Results: Average TKS value was -29.57 +/- 5.65 (Range from -43.11 to -7.09) in normal eyes and 36.23 +/- 24.3 (Range from -16.82 to 97.45) in keratoconus eyes (p < 0.001). Receiver operating characteristic curve analyses showed perfect predictive accuracy for TKS (ROC 1.0 (95% CI: 0.999-1.0)). The TKS distinguished the keratoconus group from the normal group with 99% sensitivity and 99% specificity at the best cut-off point of -12.45. Conclusions: The new scoring system measured by the Scheimpflug imaging system provides perfect discrimination of keratoconus from normal corneas. (C) 2016 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved
Comparative Analysis of Anterior Segment Parameters in Normal and Keratoconus Eyes Generated by Scheimpflug Tomography
No full textPurpose. To assess and compare the anterior and posterior corneal surface parameters, keratoconus indices, thickness profile data, and data from enhanced elevation maps of keratoconic and normal corneas with the Pentacam Scheimpflug corneal tomography and to determine the sensitivity and specificity of these parameters in discriminating keratoconus from normal eyes. Methods. The study included 656 keratoconus eyes and 515 healthy eyes with a mean age of 30.95 +/- 9.25 and 32.90 +/- 14.78 years, respectively. Forty parameters obtained from the Pentacam tomography were assessed by the receiver operating characteristic curve analysis for their efficiency. Results. Receiver operating characteristic curve analyses showed excellent predictive accuracy (area under the curve, ranging from 0.914 to 0.972) for 21 of the 40 parameters evaluated. Among all parameters indices of vertical asymmetry, keratoconus index, front elevation at thinnest location, back elevation at thinnest location, Ambrosio Relational Thickness (ARTmax), deviation of average pachymetric progression, deviation of ARTmax, and total deviation showed excellent (>90%) sensitivity and specificity in addition to excellent area under the receiver operating characteristic curve (AUROC). Conclusions. Parameters derived from the topometric and Belin-Ambrosio enhanced ectasia display maps very effectively discriminate keratoconus from normal corneas with excellent sensitivity and specificity
Variations on the Author
Get PDF“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
Corneal and Conjunctival Sensitivity in Patients With Dry Eye: The Effect of Topical Cyclosporine Therapy
No full textPurpose: To evaluate changes in mechanical sensitivity of cornea and conjunctiva in patients with dry eye disease unresponsive to artificial tears therapy and to investigate the effect of topical cyclosporine therapy on sensitivity of the ocular surface. Methods: Thirty-seven patients with dry eye disease and 35 healthy control subjects were enrolled to this prospective study. All patients included in the study completed a 3-month run-in period of using nonpreserved artificial tear supplements, but all failed to achieve adequate subjective or objective improvement. Patients were then instructed to use topical cyclosporine A 0.05% twice a day. Pre- and posttreatment (1, 3, and 6 months) evaluations included, corneal and conjunctival sensitivity testing with the Cochet-Bonnet esthesiometer, Subjective symptom scoring, fluorescein and lissamine green staining, Schirmer test, and tear breakup time (BUT). Results: Conjunctival and corneal sensitivities were significantly lower in patients with dry eye compared with controls (P < 0.0001). In patients with dry eye, corneal sensitivity correlated positively with conjunctival sensitivity and negatively with ocular surface staining scores. Conjunctival sensitivity correlated negatively with the duration of dry eye disease, the total symptom severity score, and the severity of dryness symptom and positively with Schirmer test and tear BUT. Corneal and conjunctival sensitivities did not change significantly after artificial tear therapy (P > 0.05). After topical cyclosporine, statistically significant improvements from baseline were observed in corneal sensitivity at 3- and 6-month visits (P < 0.001). For conjunctival sensitivity, statistically significant improvements from baseline were seen at all follow-up visits (P < 0.0001). Topical cyclosporine treatment also led to significant improvements in symptom scores, Schirmer test, tear BUT, and ocular surface staining scores (P < 0.0001). Conclusions: The mechanical sensitivity of cornea and conjunctiva to tactile stimulus is reduced in patients with dry eye. Our findings suggest that topical cyclosporine may be effective in improving this reduced mechanical sensitivity of the ocular surface
Influence of Apical Clearance on Mini-Scleral Lens Settling, Clinical Performance, and Corneal Thickness Changes
No full textPurpose: The purpose of this work was to define the timing and magnitude of scleral contact lens settling, the factors influencing settling, and to examine whether the amount of apical clearance has an impact on clinical performance or is associated with hypoxia-induced corneal changes. Methods: Eleven patients (22 eyes) with keratoconus were fitted with a mini-scleral lens (Esclera, Brazil). Three different lenses with successively greater sagittal depths were applied to achieve 3 levels of initial apical clearance: 100 to 200 mu m (low), 200 to 300 mu m (medium), and greater than 300 mu m (high). Corneal apical clearance was measured at 15 min, 1, 2, 4, 6, and 8 hr with optical coherence tomography (OCT). Central corneal thickness was measured with OCT and Pentacam, in the morning and immediately after removal of the contact lens. Results: Mean settling was 26.8 +/- 18.8 mu m (42.7%) at 1 hr, 39.5 +/- 26.5 mu m (62.9%) at 2 hr, 50.7 +/- 31.6 mu m (80.8%) at 4 hr, 57.4 +/- 34.6 mu m (91.4%) at 6 hr, and 62.8 +/- 38.4 mu m (100%) at 8 hr. Settling rate was significantly lower in low apical clearance group (P = 0.01). The smaller diameter lenses settled more (P = 0.03). There was a slight statistically significant increase of 1.3% in central corneal thickness measured with OCT (P = 0.03). Central corneal thickness measured with Pentacam at three locations increased slightly (P = 0.001). Settling showed significant intrasubject and intersubject variations. The amount of corneal swelling and comfort scores did not differ significantly according to apical clearance. Conclusions: The average amount of settling was 62.8 mu m after 8 hr, 80% of which occurred during the first 4 hr. Slight corneal swelling (1.3%) occurred after 8 hr of wear
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