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Canaloplasty in the Treatment of Open-Angle Glaucoma: A Review of Patient Selection and Outcomes.
Canaloplasty is a relatively new non-penetrating surgery for the reduction of intraocular pressure in patients affected by glaucoma. The technique uses a microcatheter to perform a 360 º cannulation of Schlemm's canal and leaves in place a tension suture providing an inward distension. It aims to restore the physiological outflow pathways of the aqueous humour and is independent of external wound healing. Several studies have shown that canaloplasty is effective in reducing intraocular pressure and has a low rate of complications, especially compared with trabeculectomy, the gold standard for glaucoma surgery. Currently, canaloplasty is indicated in patients with open-angle glaucoma, having a mild to moderate disease, and the combination with cataract phacoemulsification may provide further intraocular pressure reduction. This article reviews canaloplasty indications, results and complications and analyses its outcomes compared with traditional penetrating and non-penetrating techniques
CCD Washington photometry of four poorly studied open clusters in the two inner quadrants of the galactic plane
Complementing our Washington photometric studies on Galactic open clusters
(OCs), we now focus on four poorly studied OCs located in the first and fourth
Galactic quadrants, namely BH 84, NGC 5381, BH 211 and Czernik 37. We have
obtained CCD photometry in the Washington system and passbands down
to 18.5 magnitudes for these four clusters. Their positions and
sizes were determined using the stellar density radial profiles. We derived
reddening, distance, age and metallicity of the clusters from extracted
color-magnitude diagrams (CMDs), using theoretical isochrones
computed for the Washington system. There are no previous photometric data in
the optical band for BH 84, NGC 5381 and BH 211. The CMDs of the observed
clusters show relatively well defined main sequences, except for Czernik 37,
wherein significant differential reddening seems to be present. The red giant
clump is clearly seen only in BH 211. For this cluster, we estimated the age in
(1000) Myr, assuming a metallicity of = 0.019. BH 84 was
found to be much older than it was previously believed, while NGC 5381 happened
to be much younger than previously reported. The heliocentric distances to
these clusters are found to range between 1.4 and 3.4 kpc. BH 84 appears to be
located at the solar galactocentric distance, while NGC 5381, BH 211 and
Czernik 37 are situated inside the solar ring.Comment: 30 pages, 9 figures, 10 table
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Vision-related quality of life and symptom perception change over time in newly-diagnosed primary open angle glaucoma patients.
To evaluate the change over time of vision-related quality of life (QoL) and glaucoma symptoms in a population of newly-diagnosed primary open angle glaucoma (POAG) patients. Multicenter, prospective study. Consecutive newly-diagnosed POAG patients were enrolled and followed-up for one year. Follow-up visits were scheduled at 6 and 12 months from baseline. At each visit, vision-related QoL and glaucoma-related symptoms were assessed by the means of the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and the Glaucoma Symptom Scale (GSS), respectively. Trends over time for NEI-VFQ-25 and GSS scores were evaluated with longitudinal linear mixed models. One-hundred seventy-eight patients were included in the analysis. At baseline, early to moderate glaucoma stages were associated with higher scores for most GSS and NEI-VFQ-25 items, while lower best-corrected visual acuity was associated with lower scores for 4 of the 12 NEI-VFQ-25 items. During the follow-up, all the GSS scores, the NEI-VFQ-25 total score, and 7 of the 12 NEI-VFQ-25 scores significantly improved (p < 0.05). In multivariate model, higher increases of most GSS and NEI-VFQ-25 scores were modeled in patients with low scores at baseline. Vision-related QoL and glaucoma-related symptom perception significantly improved during the one-year follow-up in this population of newly diagnosed POAG patients
Visual field loss and vision-related quality of life in the Italian Primary Open Angle Glaucoma Study.
The aim of this study was to examine the relationship between visual field (VF) loss, vision-related quality of life (QoL) and glaucoma-related symptoms in a large cohort of primary open angle glaucoma (POAG) patients. POAG patients with or without VF defects or "glaucoma suspect" patients were considered eligible. QoL was assessed using the validated versions of the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and glaucoma-related symptoms were assessed using the Glaucoma Symptom Scale (GSS). Patients were classified as having VF damage in one eye (VFD-1), both eyes (VFD-2), or neither eye (VFD-0). 3227 patients were enrolled and 2940 were eligible for the analysis. 13.4% of patients were classified in the VFD-0, 23.7% in the VFD-1, and 62.9% in the VFD-2 group. GSS visual symptoms domain (Func-4) and GSS non-visual symptoms domain (Symp-6) scores were similar for the VFD-0 and VFD-1 groups (p = 0.133 and p = 0.834 for Func-4 and Symp-6, respectively). VFD-0 group had higher scores than VFD-2 both in Func-4 (p < 0.001) and Symp-6 domains (p = 0.035). Regarding the NEI-VFQ-25, our data demonstrated that bilateral VF defects are associated with vision-related QoL deterioration, irrespective of visual acuity
Learning effect of humphrey matrix frequency doubling technology perimetry in patients with ocular hypertension
Aim: To evaluate the learning effect of Frequency Doubling Technology (FDT) perimetry using the Humphrey Matrix-FDT perimetry (Matrix) 24-2 full-threshold program on patients with 7 ocular hypertension experienced with standard automated perimetry. Methods: Twenty-four patients with Ocular hypertension underwent 5 full-threshold Matrix tests at intervals of 5 2 days. Learning effect was defined as an improvement at results for duration, perimetric indices, foveal sensitivity, Glaucoma Hemifield Test, and the number of points with a P < 5% and < 1% in the total and pattern deviation maps. Eccentricity, hemifield, and quadrant sensitivities were also addressed as Sources of differences in learning effect. Test-retest variability was also calculated for each repetition as the mean of the point-to-point interindividual standard deviations. Results: A learning effect was demonstrated for mean defect (P = 0.031, analysis of variance) and foveal sensitivity (P = 0.009) and it only affected the first test for both parameters. All the other parameters did not show any significant learning effect. The effect was independent From eccentricity and quadrant or hemifield sensitivities. Conclusions: The results of this study demonstrate that the learning effect for Matrix-FDT is mild and it may affect only the first test. Caution is needed in the analysis of the first Matrix-FDT examination and retest may be advisable in the presence of low mean defect
Commercial farming and agribusiness in South Africa and their changing roles in Africa’s agro-food system
Our paper is on commercial farming and agribusiness in South Africa and their changing roles in Africa’s agro-food system, as a response to debates and theoretical propositions about internal agrarian change in BRICS countries and their relations with other middle-income
countries and the old hubs of capital.
South Africa is of course an outlier among the BRICS group of countries, given its far smaller economy, and was included only in 2010, as the only candidate that could be seen as economically and politically dominant in Africa – though by last year, Nigeria had overtaken South Africa as the largest economy in Africa
Double nucleus in M83
M 83 is one of the nearest galaxies with an enhanced nuclear star formation
and it presents one of the best opportunities to study the kinematics and
physical properties of a circumnuclear starburst. Our three-dimensional
spectroscopy data in R band confirm the presence of a secondary nucleus or mass
concentration (previously suggested by Thatte and coworkers). We determine the
position of this hidden nucleus, which would be more massive than the visible
one, and was not detected in the optical HST images due, probably, to the
strong dust extinction. The optical nucleus has a mass of 5 x 10^6 M_Sun / sin
i (r < 1''.5), and the hidden nucleus, located 3''.9 +/- 0''.5 at the NW (PA
271 +/- 15 deg) of the optical nucleus, would have a mass of 1 x 10^7 M_Sun /
sin i (r < 1''.5). The emission line ratio map also unveils the presence of a
second circumnuclear ring structure, previously discovered by IR imaging
(Elmegreen and coworkers). The data allow us to resolve the behavior of the
interstellar medium inside the circumnuclear ring and around the binary mass
concentration.Comment: 28 pages, 11 figures. Discussion updated. Published versio
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Author Correction: Visual field loss and vision-related quality of life in the Italian Primary Open Angle Glaucoma Study.
An amendment to this paper has been published and can be accessed via a link at the top of the paper
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