1,720,956 research outputs found
Refractory full thickness macular hole: current surgical management
No full textThis review aims to collect the proposed surgical techniques for treating full thickness macular hole (FTMH) refractory to pars plana vitrectomy and internal limiting membrane (ILM) peeling and to analyse and compare anatomical and functional outcomes in order to evaluate their efficacy. The articles were grouped according to the surgical techniques used. Refractory FTMH closure rate and best-corrected visual acuity (BCVA) gain were the two analysed parameters. Thirty-six articles were selected. Ten surgical technique subgroups were defined: autologous platelet concentrate (APC); lens capsular flap transplantation (LCFT); autologous free ILM flap transplantation (free ILM flap); enlargement of ILM peeling, macular hole hydrodissection (MHH), autologous retinal graft (ARG), silicon oil (SO), human amniotic membrane (hAM), perifoveal relaxing retinotomy, arcuate temporal retinotomy. Refractory FTMH closure rate was similar among subgroups, not significant heterogeneity emerged (p = 0.176). BCVA gain showed a significant dependence on surgical technique (p < 0.0001), significant heterogeneity among subgroups emerged (p < 0.0001). Three sets of surgical technique subgroups with a homogeneous BCVA gain were defined: high BCVA gain (hAM); intermediate BCVA gain (APC, ARG, LCFT, MHH, SO); low BCVA gain (free ILM flap, enlargement of peeling, arcuate temporal retinotomy). In terms of visual recovery, the most efficient technique for treating refractory FTMH is hAM, lens capsular flap and APC that allow to obtain better functional outcomes than free ILM flap. MHH, ARG, perifoveal relaxing and arcuate temporal retinotomy require complex and unjustified surgical manoeuvres in view of the surgical alternatives with overlapping anatomical and functional results
Novel approaches to the assessment and treatment of lamellar macular hole
No full textPurpose: To analyse morpho-functional foveal changes in eyes with lamellar macular hole (LMH) by an integrated assessment of short-wavelength fundus autofluorescence (SW-FAF) and microperimetry (SW-FAF/microperimetry integrated assessment) before and after treatment with a technique of double-inverted flaps of epiretinal proliferation (EP) and internal limiting membrane (ILM). Methods: Clinical and tomographic parameters were best-corrected visual acuity (BCVA), LMH size, central retinal thickness (CRT) and outer retinal layer integrity. SW-FAF/microperimetry integrated assessment allowed to analyse retinal sensitivity (RS) and FAF status of the fovea by an overlay of RS map on SW-FAF image. Follow-up was at baseline, 1, 3, 6 and 12 postoperative months. Results: Forty pseudophakic eyes. Hyper-FAF area was associated with larger LMH size (p = 0.0073) and inversely correlated with CRT (p = 0.021). Lower preoperative RS was observed in hyper-FAF than normo-FAF areas (p = 0.0117). External limiting membrane (ELM) defect was associated with worse BCVA (p = 0.0004). After surgery, BCVA improved (p = 0.001) and it was related to ELM recovery (p = 0.00483), hyper-FAF area decreased (p = 0.001), and RS increased (p = 0.440). Hyper-FAF points that normalized their FAF were associated with higher RS improvement compared to unchanged points. Conclusion: Short-wavelength fundus autofluorescence/microperimetry integrated assessment provides important information on the entity of damage of LMH and on postoperative recovery. Double-inverted EP and ILM flap technique is safe and effective for LMH treatment
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
A possible strategic role of air during pars plana vitrectomy for macula-involving rhegmatogenous retinal detachment
No full textAim: To evaluate the advantages and safety of vitrectomy under air for treating macula-involving rhegmatogenous retinal detachment (RRD). Methods: Consecutive patients with macula-involving RRD who underwent vitrectomy under air were recruited. Demographic and clinical data were: age, gender, eye, lens status, best corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution (logMAR), axial length, intraocular pressure (IOP). RRD parameters were: RRD extent, retinal breaks number. Surgical data were: cataract surgery, tamponade used. Postoperative parameters were: BCVA, IOP at first, third, sixth month, recurrent RD, incidence of retinal folds, subretinal fluid (SRF) persistence, macular displacement. Results: Seventy-one eyes (71 patients) were recruited. Cataract surgery was performed in 32 of 45 phakic patients. The tamponade used was: sulfur hexafluoride 18% (41), silicon oil (SO) (26), high-density SO (4). BCVA improved significantly from baseline (1.2 ± 0.4 logMAR) to the last control (0.8 ± 0.7 logMAR) (P = 0.03285). Recurrent RD incidence was 14.1%. Postoperative complications were: retinal folds (2), SRF persistence (3), macular displacement (2). Conclusion: Vitrectomy under air is a safe alternative technique for treating macula-involving RRD. Vitrectomy under air allows surgeon to remove accurately the vitreous from the peripheral retina and facilitates the removal of SRF reducing the complications related to its postoperative persistence
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
Reper intraocular lens with artificial iris: implantation techniques and outcomes
No full textThe authors describe the surgical techniques to implant a novel intraocular lens with artificial iris (Reper) in patients affected by traumatic aphakia and aniridia. Two surgical approaches are proposed: implantation by suture-loaded cartridge and “open sky” implantation combined with penetrating keratoplasty. The method of establishing the exact position of the scleral fixation points and the pre-assembly of the suture of Reper before its implantation are the main novel proposed surgical procedures. The rationale is to minimize surgical procedures in the anterior chamber and to prevent knot loosening and lens tilting. The simultaneous treatment of aphakia and aniridia with a single prosthesis, the stability of the Reper and the functional, anatomical and aesthetic outcomes obtained are the highlighted advantages in this study
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
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