bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent highlights from Cluster, the first 3-D magnetospheric mission
Authors: Escoubet C. P. , Masson A. , Laakso H. , Goldstein M. L.
Published: October 2015

Abstract. The Cluster mission has been operated successfully for 14 years. During this time period, the evolution of the orbit has enabled Cluster to sample many more magnetospheric regions than was initially anticipated. So far, the separation of the Cluster spacecraft has been changed more than 30 times and has ranged from a few kilometres up to 36 000 km. These orbital changes have enabled the science team to address a wide variety of scientific objectives in key regions of Earth's geospace environment: the solar wind and bow shock, the magnetopause, polar cusps, magnetotail, plasmasphere and the auroral acceleration region. Recent results have shed new light on solar wind turbulence. They showed that the magnetosheath can be asymmetric under low Mach number and that it can contain density enhancement that may affect the magnetosphere. The magnetopause was found to be thinner and to have a higher current density on the duskside than on the dawnside. New methods have been used to obtain characteristic of the magnetotail current sheet and high-temporal-resolution measurements of electron pitch angle within flux transfer events (FTEs). Plasmaspheric wind has been discovered, and the refilling of the plasmasphere was observed for the first time over a very wide range of L shells. New models of global electric and magnetic fields of the magnetosphere have been obtained where Cluster, due to its polar orbit, has been essential. Finally, magnetic reconnection was viewed for the first time with high-resolution wave and electron measurements and acceleration of plasma was observed during times of varying rate of magnetic reconnection. The analysis of Cluster data was facilitated by the creation of the Cluster Science Data System (CSDS) and the Cluster Science Archive (CSA). Those systems were implemented to provide, for the first time for a plasma physics mission, a long-term public archive of all calibrated high-resolution data from all instruments.
The large-scale anisotropy with the PAMELA calorimeter
Authors: Karelin A. , Adriani O. , Barbarino G. , Bazilevskaya G. , Bellotti R. , Boezio M. , Bogomolov E. , Bongi M. , Bonvicini V. , Bottai S. , Bruno A. , Cafagna F. , Campana D. , Carbone R. , Carlson P. , Casolino M. , Castellini G. , De Donato C. , De Santis C. , De Simone N. , Di Felice V. , Formato V. , Galper A. , Koldashov S. , Koldobskiy S. , Krut'kov S. , Kvashnin A. , Leonov A. , Malakhov V. , Marcelli L. , Martucci M. , Mayorov A. , Menn W. , Mergé M. , Mikhailov V. , Mocchiutti E. , Monaco A. , Mori N. , Munini R. , Osteria G. , Palma F. , Panico B. , Papini P. , Pearce M. , Picozza P. , Ricci M. , Ricciarini S. , Sarkar R. , Simon M. , Scotti V. , Sparvoli R. , Spillantini P. , Stozhkov Y. , Vacchi A. , Vannuccini E. , Vasilyev G. , Voronov S. , Yurkin Y. , Zampa G. , Zampa N.
Published: October 2015

Abstract. The large-scale anisotropy (or the so-called star-diurnal wave) has been studied using the calorimeter of the space-born experiment PAMELA. The cosmic ray anisotropy has been obtained for the Southern and Northern hemispheres simultaneously in the equatorial coordinate system for the time period 2006–2014. The dipole amplitude and phase have been measured for energies 1–20 TeV n-1.
Recent decline of the Black Sea oxygen inventory
Authors: Capet A. , Stanev E. V. , Beckers J.-M. , Murray J. W. , Grégoire M.
Published: October 2015

Abstract. We show that from 1955 to 2013, the inventory of oxygen in the Black Sea has decreased by 36 % and the basin-averaged oxygen penetration depth has decreased from 140 m in 1955 to 90 m in 2013, which is the shallowest annual value recorded during that period. The oxygenated Black Sea surface layer separates the world's largest reservoir of toxic hydrogen sulphide from the atmosphere. The threat of chemocline excursion events led to hot debates in the past decades arguing on the vertical stability of the Black Sea oxic/suboxic interface. In the 1970s and 1980s the Black Sea faced severe eutrophication. Enhanced respiration rates reduced the thickness of the oxygenated layer. The consecutive increase of oxygen inventory in 1985–1995 supported arguments in favor of the stability of the oxic layer. Concomitant with a reduction of nutrient loads, this increase also supported the perception of a Black Sea recovering from eutrophication. More recently, atmospheric warming was shown to reduce the ventilation of the lower oxic layer by lowering Cold Intermediate Layer (CIL) formation rates. The debate on the vertical migration of the oxic interface also addressed the natural spatial variability affecting Black Sea properties when expressed in terms of depth. Here we show that using isopycnal coordinates does not free from a significant spatial variability of oxygen penetration depths. Considering this spatial variability, the analysis of a composite historical set of oxygen profiles evidenced a significant shoaling of the oxic layer, and showed that the transient "recovery" of the 1990s was mainly a result of increased CIL formation rates during that period. As both atmospheric warming and eutrophication are expected to increase in the near future, monitoring the dynamics of the Black Sea oxic layer is required to assess the threat of further shoaling.
Composition of ammonia-oxidizing archaea and their contribution to nitrification in a high-temperature hot spring
Authors: Chen S. , Peng X.-T. , Xu H.-C. , Ta K.-W.
Published: October 2015

Abstract. The oxidation of ammonia by microbes and associated organisms has been shown to occur in diverse natural environments. However, the contribution of ammonia-oxidizing archaea to nitrification in high-temperature environments remains unclear. Here, we studied in situ ammonia oxidation rates and the abundance of ammonia-oxidizing archaea (AOA) in surface and bottom sediments at 77 °C in the Gongxiaoshe hot spring, Tengchong, Yunnan, China. The in situ ammonia oxidation rates measured by the 15N–NO3- pool dilution technique in the surface sinter and bottom sediments were 4.8 and 5.3 nmol N g−1 h−1, respectively. Relative abundances of Crenarchaea in both samples were determined by fluorescence in situ hybridization (FISH). Phylogenetic analysis of 16S rRNA genes showed high sequence similarity to thermophilic "Candidatus Nitrosocaldus yellowstonii", which represented the most abundant operation taxonomic units (OTU) in both sediments. Furthermore, bacterial amoA was not detected in this study. Quantitative PCR (qPCR) indicated that AOA and 16S rRNA genes were present in the range of 2.75 to 9.80 × 105 and 0.128 to 1.96 × 108 gene copies g−1 sediment. The cell-specific nitrification rates were estimated to be in the range of 0.41 to 0.79 fmol N archaeal cell−1 h−1, which is consistent with earlier estimates in estuary environments. This study demonstrated that AOA were widely involved in nitrification in this hot spring. It further indicated the importance of archaea rather than bacteria in driving the nitrogen cycle in terrestrial geothermal environments.
The climate reconstruction in Shandong Peninsula, North China during the last millennia based on stalagmite laminae
Authors: Wang Q. , Zhou H. , Cheng K. , Chi H. , Shen C. , Wang C. , Ma Q.
Published: October 2015

Abstract. Stalagmite ky1 was collected from Kaiyuan Cave in coastal areas of Shandong Peninsula, northern China, located at warm temperate zone and East Asia monsoon area, it was 75 mm in length, and the top 42.77 mm developed 678 laminae. Based on high precision dating with U-230Th technique, by continuous laminae counting, it can be confirmed that the 1st and 678th layer were 1217 and 1892 AD from top to bottom respectively. By the measurement of layer thickness and δ18O values, we got the layer thickness data and δ18O value time series data from 1217 to 1892 AD, analyzed the climatic significance of layer thickness variation on the basis of comparison. The result show that, in the 678 years from 1217 to 1892 AD, both the layer thickness variation of stalagmite ky1 and the variation of layer thickness fluctuation degree have obvious staged characteristic, and completely synchronized with the contemporaneous summer monsoon intensity/precipitation in time. Among, the thickness of layer and summer monsoon intensity/precipitation have negative correlation themselves. On the other hand, the layer thickness and the fluctuation degree of summer monsoon intensity/precipitation have positive correlation themselves. Therefore, Kaiyuan Cave, in the coastal area of warm temperate zone and East Asia monsoon area, the variation of layer thickness are relate to climatic factors variation themselves, and relate to climate stability degree in addition. For to achieve this, in the coastal area of warm temperate zone and East Asia monsoon area, the climate change between LIA and MWP, in addition to presented like less precipitation and low temperature that is to say dry and cold, also showed the climate stability degree obvious decreased.
A soil diffusion–reaction model for surface COS flux: COSSM v1
Authors: Sun W. , Maseyk K. , Lett C. , Seibt U.
Published: October 2015

Abstract. Soil exchange of carbonyl sulfide (COS) is the second largest COS flux in terrestrial ecosystems. A novel application of COS is the separation of gross primary productivity (GPP) from concomitant respiration. This method requires that soil COS exchange is relatively small and can be well quantified. Existing models for soil COS flux have incorporated empirical temperature and moisture functions derived from laboratory experiments but not explicitly resolved diffusion in the soil column. We developed a mechanistic diffusion–reaction model for soil COS exchange that accounts for COS uptake and production, relates source–sink terms to environmental variables, and has an option to enable surface litter layers. We evaluated the model with field data from a wheat field (Southern Great Plains (SGP), OK, USA) and an oak woodland (Stunt Ranch Reserve, CA, USA). The model was able to reproduce all observed features of soil COS exchange such as diurnal variations and sink–source transitions. We found that soil COS uptake is strongly diffusion controlled and limited by low COS concentrations in the soil if there is COS uptake in the litter layer. The model provides novel insights into the balance between soil COS uptake and production: a higher COS production capacity was required despite lower COS emissions during the growing season compared to the post-senescence period at SGP, and unchanged COS uptake capacity despite the dominant role of COS emissions after senescence. Once there is a database of soil COS parameters for key biomes, we expect the model will also be useful to simulate soil COS exchange at regional to global scales.
The improvement of soil thermodynamics and its effects on land surface meteorology in the IPSL climate model
Authors: Wang F. , Cheruy F. , Dufresne J.-L.
Published: October 2015

Abstract. This paper describes the implementation of an improved soil thermodynamics in the hydrological module of Earth System Model (ESM) developed at the Institut Pierre Simon Laplace (IPSL) and its effects on land surface meteorology in the IPSL climate model. A common vertical discretization scheme for the soil moisture and for the soil temperature is adopted. In addition to the heat conduction process, the heat transported by liquid water into the soil is modeled. The thermal conductivity and the heat capacity are parameterized as a function of the soil moisture and the texture. Preliminary tests are performed in an idealized 1-D framework and the full model is then evaluated in the coupled land/atmospheric module of the IPSL ESM. A nudging approach is used in order to avoid the time-consuming long-term simulations required to account for the natural variability of the climate. Thanks to this nudging approach, the effects of the modified parameterizations can be modeled. The dependence of the soil thermal properties on moisture and texture lead to the most significant changes in the surface energy budget and in the surface temperature, with the strongest effects on the surface energy budget taking place over dry areas and during the night. This has important consequences on the mean surface temperature over dry areas and during the night and on its short-term variability. The parameterization of the soil thermal properties could therefore explain some of the temperature biases and part of the dispersion over dry areas in simulations of extreme events such as heat waves in state-of-the-art climate models.
Impact of climate change on groundwater in a confined Mediterranean aquifer
Authors: Caballero Y. , Ladouche B.
Published: October 2015

Abstract. This paper presents an inverse modeling method based on wavelet analysis, devoted to assessment of the impacts of climate change on the groundwater resources of a confined coastal multi-layer aquifer, located in the south of France (Pyrénées-Orientales). The hydraulic behavior of the aquifer is described based on the results of a model calibrated to simulate the groundwater dynamics observed on two representative piezometers. The relative contributions of the climate and pumping forcings to the piezometric variations are quantified. The results illustrate in quantitative terms the dominant influence of pumping on the temporal variations of the hydraulic head of the aquifer. Based on this specific behavior simulation, we show the moderate vulnerability of such confined aquifers to climate change. Some insights regarding pumping strategies for confined coastal aquifers that could contribute towards preserving their good status in future are also provided.
Effect of Intracameral Triamcinolone Acetonide on Postoperative Intraocular Inflammation in Pediatric Traumatic Cataract
Authors: Mohamed Tarek A. , Soliman Wael , Fathalla Ahmed M.
Published: October 2015

Purpose

To study the effect of a single intracameral injection of triamcinolone acetonide at the end of pediatric traumatic cataract surgery on postoperative inflammation.

Methods

This prospective interventional study comprised 40 eyes of children with unilateral traumatic cataract. Patients were classified into 2 groups: the study group, in which intraoperative intracameral triamcinolone acetonide (2 mg) was used at the end of surgery; and a control group, which did not receive intracameral triamcinolone acetonide.

Results

The study group included 20 eyes of patients with an average age of 6 ± 2.8 years. The control group included 20 eyes of patients with an average age of 6 ± 2.1 years. No serious intraoperative complications occurred. In the immediate postoperative period, 3 eyes of the control group (15.0%) developed a fibrinous anterior chamber reaction. None of the study group eyes developed a similar reaction. There were no cases of endophthalmitis. In addition, 3 eyes (15%) in the control group had obscuration of the visual axis at the last follow-up. This complication was not encountered in the study group. Posterior synechiae and cellular deposits were observed in 4 eyes (20%) in the study group and 8 eyes (40%) in the control group at 1 month and at the last follow-up.

Conclusions

The use of intracameral triamcinolone decreased anterior segment inflammation postoperatively in children who had surgery for traumatic cataract.
Grooved and Nongrooved Clear Corneal Incisions in Phacoemulsification: Permeability Study
Authors: Bergamasco Victor D. , Antunes Victor A.C. , Hida Richard Y. , Malavazzi Gustavo R.
Published: October 2015

Purpose

To detect the inflow of trypan blue through grooved and nongrooved sutureless self-sealing clear corneal incisions at the end of phacoemulsification as compared to a control group.

Methods

A prospective randomized masked trial considered 52 eyes randomized into 3 groups in which phacoemulsification was performed: group A, nongrooved incisions; group B, grooved incisions; and group C, controls. By the end of each surgery, trypan blue was instilled on the ocular surface in groups A and B and rinsed out after 2 minutes. A sample of the anterior chamber content was collected and analyzed by high-performance liquid chromatography to identify and quantify the trypan blue concentration. The presence of trypan blue was expressed as a specific single peak graphic image. The mean areas of these peaks were used to assess the groups using a nonparametric Mann-Whitney test.

Results

There was a statistically significant difference between the nongrooved incisions group and the control group (p = 0.0448). No significant difference was observed between group B (grooved incision) and controls (p = 0.1800).

Conclusions

Trypan blue was detected in the anterior chamber when nongrooved clear corneal incision was used. There was no trypan blue detection in the group with grooved clear corneal main incisions.
Cataract Surgery in Patients with Nanophthalmos: Results and Complications
Authors: Lemos José A. , Rodrigues Pedro , Resende Rui A. , Menezes Carlos , Gonçalves Rita S. , Coelho Pedro
Published: October 2015

Purpose

To evaluate phacoemulsification surgery results and complications in patients with nanophthalmos.

Methods

The records of 9 patients with nanophthalmos who had cataract surgery from January 2011 through January 2015 were retrospectively reviewed. Nanophthalmos was diagnosed by the presence of an eye with an axial length (AL) less than 20.5 mm. The records were reviewed for ocular diagnosis, keratometry, anterior chamber depth (ACD), AL, ocular surgeries, visual acuity, and complications.

Results

A total of 14 eyes of 9 patients (8 women, 1 man) with a mean age of 72 years (range 48-86) were reviewed. Mean AL was 18.72 mm and mean ACD was 2.30 mm. Mean preoperative spherical equivalent (+8.55 ± 6.44 diopters (D)) was reduced to +0.30 ± 2.17 D at last follow-up visit. Mean best-corrected visual acuity (BCVA) was +0.68 ± 0.55 logarithm of the minimum angle of resolution (logMAR) preoperatively and improved to +0.55 ± 0.73 logMAR at last follow-up visit. Visual acuity remained stable or improved in 11 eyes. Five eyes did not achieve final BCVA ≥+0.3 logMAR. Complications occurred in 3 eyes (21.4%) and included 1 case of posterior capsule rupture, 1 case of severe iritis and rhegmatogenous retinal detachment 2 weeks postoperatively, and 1 other case of iritis. No postoperative uveal effusion was seen.

Conclusions

Although phacoemulsification seems to be relatively safe in nanophthalmic eyes, surgeons need to be aware of the challenges of this procedure in these high-risk eyes. Nevertheless, with careful preoperative evaluation and planning, most cases were uncomplicated and resulted in improvement of BCVA.
Improved Outcome after Primary Vitrectomy in Diabetic Patients Treated with Statins
Authors: Tuuminen Raimo , Sahanne Sari , Haukka Jari , Loukovaara Sirpa
Published: October 2015

Purpose

To evaluate the effect of preoperative statin treatment on the outcome of primary vitrectomy in type 1 and 2 diabetic patients.

Methods

In this open, observational institutional study, a total of 192 eyes of 171 type 1 and 2 adult diabetic patients admitted for primary vitrectomy for management of sight-threatening forms of diabetic retinopathy were divided according to the use of lipid-lowering therapy: those with statin treatment (79 eyes of 73 patients) and those taking no statin medication (113 eyes of 98 patients). One-month best-corrected visual acuity (BCVA) gain and cumulative 12-month revitrectomy frequency were analyzed.

Results

In multivariate linear regression, diabetic patients with statin treatment had a better 1-month BCVA improvement than did those without statin treatment (absolute difference 0.26, 95% confidence interval [CI] 0.02-0.50, p = 0.028). Subgroup analysis revealed that diabetic patients on statin had better postoperative BCVA improvement when preoperative status included partial or panretinal laser photocoagulation (p = 0.042 and p = 0.049) and anti-vascular endothelial growth factor therapy (p = 0.011). Moreover, diabetic patients with preoperative macular edema (p = 0.009), vitreous hemorrhage (p<0.001), proliferative retinopathy (p<0.001), or tractional retinal detachment (p = 0.010) had better BCVA recovery if receiving statin. In Cox proportional hazards regression model, revitrectomies in our 12-month follow-up were less frequent in diabetic patients on statin treatment (hazard ratio 0.28, 95% CI 0.08-0.93, p = 0.037).

Conclusions

These data provide novel insight into the potential clinical benefit for patients with sight-threatening diabetic retinopathy undergoing vitrectomy treated with statin.
A Case of Severe Corneal Flattening after Descemet Stripping Endothelial Keratoplasty
Authors: Fernández-López Ester , Miron Alina , Pogorelova Svetlana , Oganesyan Oganes , Baydoun Lamis , Melles Gerrit R.J.
Published: October 2015

Purpose

To report a case of extreme corneal flattening after initially uneventful Descemet stripping endothelial keratoplasty (DSEK).

Methods

A 76-year-old man underwent uneventful DSEK for pseudophakic bullous keratopathy (PBK) in his left eye. Postoperative evaluations were performed using anterior segment optical coherence tomography and biomicroscopy.

Results

The DSEK graft showed full adherence to the host stroma. Two weeks after surgery, the transplanted cornea developed pronounced flattening of the central corneal curvature accompanied by graft folds and remained unchanged until the most recent follow-up 20 weeks after surgery.

Conclusions

Severe corneal flattening may be an undescribed complication occurring after uneventful DSEK, without any concomitant ocular pathology or detectable cause.
Smartphone-Based Fundus Camera Device (MII Ret Cam) and Technique with Ability to Image Peripheral Retina
Authors: Sharma Ashish , Subramaniam Saranya Devi , Ramachandran KI , Lakshmikanthan Chinnasamy , Krishna Soujanya , Sundaramoorthy Selva K.
Published: October 2015

Purpose

To demonstrate an inexpensive smartphone-based fundus camera device (MII Ret Cam) and technique with ability to capture peripheral retinal pictures.

Methods

A fundus camera was designed in the form of a device that has slots to fit a smartphone (built-in camera and flash) and 20-D lens. With the help of the device and an innovative imaging technique, high-quality fundus videos were taken with easy extraction of images.

Results

The MII Ret Cam and innovative imaging technique was able to capture high-quality images of peripheral retina such as ora serrata and pars plana apart from central fundus pictures.

Conclusions

Our smartphone-based fundus camera can help clinicians to monitor diseases affecting both central and peripheral retina. It can help patients understand their disease and clinicians convincing their patients regarding need of treatment especially in cases of peripheral lesions. Imaging peripheral retina has not been demonstrated in existing smartphone-based fundus imaging techniques. The device can also be an inexpensive tool for mass screening.
Study of Spectral-Domain Optical Coherence Tomography in Children: Normal Values and Influence of Age, Sex, and Refractive Status
Authors: Pérez-García Diana , Ibañez-Alperte Juan , Remón León , Cristóbal José Ángel , Sanchez-Cano Ana , Pinilla Isabel
Published: October 2015

Purpose

To establish normal values for retinal nerve fiber layer (RNFL), macular thickness, and macular volume in children using spectral-domain optical coherence tomography (OCT).

Methods

A descriptive cross-sectional study was performed in healthy children between 3 and 14 years of age. Each child underwent a comprehensive ophthalmic examination that included 3 OCT scans with Spectralis (Heidelberg Engineering, Heidelberg, Germany). All measurements were performed by the same operator, and one eye was randomly selected. The influence of age, sex, and refraction on OCT measurements was analyzed.

Results

The sample consisted of 162 Caucasian subjects, mean age 8.1 ± 3.03 years. The spherical equivalent was 0.03 ± 0.19 D (range ±4 D, astigmatism <1 D). The average values were 263.69 ± 4.54 µm for central macular thickness, 0.21 ± 0.01 mm3 for central macular volume, and 100.45 ± 1.98 µm for RNFL. A significant correlation between RNFL and spherical equivalent was found for the nasal (p = 0.001), inferior (p = 0.009), and inferior nasal (p = 0.005) sectors. No differences were found with regard to sex (p>0.05). However, central macular thickness and central macular volume were correlated with age (p = 0.027, p = 0.02).

Conclusions

This study provides reference values for macular thickness, macular volume, and RNFL in healthy children.
Mobile Phones for Retinopathy of Prematurity Screening in Lagos, Nigeria, Sub-Saharan Africa
Authors: Oluleye Tunji S. , Rotimi-Samuel Adekunle , Adenekan Adetunji
Published: October 2015

Purpose

Retinopathy of prematurity (ROP), thought to be rare in Nigeria, sub-Saharan Africa, has been reported in recent studies. Developing cost-effective screening is crucial for detecting retinal changes amenable to treatment. This study describes the use of an iPhone combined with a 20-D lens in screening for ROP in Lagos, Nigeria.

Methods

The ROP screening program was approved by the Lagos University Teaching Hospital Ethical Committee. Preterm infants with birthweight of less than 1.5 kg or gestational age of less than 32 weeks were screened. In conjunction with the neonatologist, topical tropicamide (0.5%) and phenylephrine (2.5%) was used to dilate the pupils. A pediatric lid speculum was used. Indirect ophthalmoscopy was used to examine the fundus to ensure there were no missed diagnoses. An iPhone 5 with 20-D lens was used to examine the fundus. The App Filmic Pro was launched in the video mode. The camera flash served as the source of illumination. Its intensity was controlled by the app. The 20-D lens was used to capture the image of the retina, which was picked up by the camera system of the mobile phone. Another app, Aviary, was used to edit the picture.

Results

The images captured by the system were satisfactory for staging and determining the need for treatment.

Conclusions

An iPhone combined with a 20-D lens appear to be useful in screening for ROP in resource-poor settings. More studies are needed in this area.
Phacoemulsification using a Chisel-Shaped Illuminator: Enhanced Depth Trench, One-Shot Crack, and Phaco Cut
Authors: Wi Jaemin , Seo Hyejin , Lee Jong Yeon , Nam Dong Heun
Published: October 2015

Purpose

To evaluate the efficacy and outcomes of intracameral illuminator-assisted nucleofractis technique in cataract surgery.

Methods

Since June 2012, this novel technique has been performed in all cataract cases by one surgeon (approximately 300 cases of various densities). Trenching continues until the posterior plate white reflex between an endonucleus and an epinucleus is identified (enhanced depth trench). After trenching, cracking is initiated with minimal separation force, and completion of cracking is confirmed by posterior capsule reflex (one-shot crack). With followability enhanced by an elliptical phaco mode, the divided nucleus is efficiently cut into small fragments by a chisel-shaped illuminator (phaco cut).

Results

We have not experienced any capsular bag or zonular complications, and the effective phacoemulsification time seemed to be shorter than that with the conventional technique.

Conclusions

This technique simplifies the complete division of the nucleus, which is the most challenging step in safe and efficient phacoemulsification.
A Novel Technique to Release Sticking Haptic of a Single-Piece Hydrophobic Acrylic IOL using Irrigation-Aspiration Probe
Authors: Khokhar Sudarshan Kumar , Midha Neha , Patil Bharat , Nayak Bhagabat , Simakurthy Sriram
Published: October 2015

Purpose

To describe a novel technique to release sticking haptic of a single-piece hydrophobic acrylic intraocular lens (IOL) using irrigation-aspiration (I/A) probe.

Methods

In our technique, the I/A probe is introduced into the anterior chamber on Visco mode. Using the aspiration port of the I/A probe, the sticking haptic is held at its tip and suction force is built up until occlusion is noted. Then the haptic is nudged towards the center of the IOL along its curve. After the haptic is free from optic, the suction is released.

Results

Several techniques have been described to release the sticking haptic such as squeezing the haptic at the site where it sticks to the IOL or using Sinskey hook for releasing the adhesion. These techniques require extra manipulation of the IOL by introduction of surgical instruments. In our technique, we used the I/A probe itself for separating the sticky haptic successfully.

Conclusions

This technique allows separation of sticking haptic without any extra instrumentation, thus reducing intraocular maneuvering and total surgery time.
Ophthalmic Artery Blood Flow Parameters in Pseudoexfoliation Glaucoma
Authors: Kocaturk Tolga , Isikligil Isil , Uz Burcin , Dayanir Volkan , Dayanir Yelda O.
Published: October 2015

Purpose

To investigate orbital flow parameters of ophthalmic artery (OA) in patients with pseudoexfoliation glaucoma (XFG) by ultrasonography.

Methods

This case-control study included 38 patients with XFG and 32 healthy control subjects. Color Doppler imaging was performed to evaluate orbital flow parameters of OA. Receiver operating characteristic analyses were performed to define the best cutoff value.

Results

In the XFG group, decreased peak systolic velocity (p = 0.114), end diastolic velocity (p = 0.002), and increased resistivity index (RI) (p<0.001) at OA compared to healthy controls were observed. A cutoff value 0.72 for OA RI was found to have a sensitivity of 66% and specificity of 94%.

Conclusions

The results support the findings of increased vascular resistance in OA XFG. High sensitivity and specificity obtained for OA RI may be useful in evaluation of future therapeutic vascular agents.
A Therapeutic Trial of Valganciclovir in Patients with Uveitis and Positive Epstein-Barr virus Early Antigen D IgG Titers
Authors: Boonsopon Sutasinee , Maghsoudlou Armin , Kombo Ninani E. , Foster C. Stephen
Published: October 2015

Purpose

To evaluate the effectiveness of a therapeutic trial of valganciclovir in patients with uveitis with positive Epstein-Barr virus early antigen D immunoglobulin G titers (EBV EA-D).

Methods

We performed a retrospective chart review of 14 patients at the Massachusetts Eye Research and Surgery Institution who had uveitis with positive EBV EA-D but negative studies for all other causes of uveitis and were treated with valganciclovir 450 mg twice a day or valganciclovir 900 mg twice a day between January 2010 and August 2014.

Results

Nine of 14 patients, who had presumed EBV reactivation with associated intraocular inflammation, were successfully treated with valganciclovir: 3 of these were treated with valganciclovir 450 mg twice a day and 6 were treated with valganciclovir 900 mg twice a day. Five of 14 patients failed to respond to valganciclovir with persistent inflammation after at least 2 weeks of valganciclovir therapy, and were subsequently treated with immunomodulatory therapy to control inflammation.

Conclusions

Uveitis can be caused by EBV infection/reactivation. A therapeutic trial with valganciclovir 450 mg twice a day for 1 month in patients with uveitis with positive EBV EA antibody may be beneficial.
Choroidal Thickness in Systemic Arterial Hypertension
Authors: Akay Fahrettin , Gundogan Fatih Cakir , Yolcu Umit , Toyran Sami , Uzun Salih
Published: October 2015

Purpose

To assess choroidal thickness changes in young adults with systemic arterial hypertension.

Methods

This prospective study comprised 80 hypertensive patients and 80 healthy control subjects. Choroidal thickness was measured with spectral-domain optical coherence tomography (SD-OCT) (RS-3000, Nidek). Choroidal thickness was obtained at the subfovea, 500 µm, 1000 µm, and 1500 µm nasal to the fovea (N500, N1000, N1500) and 500 µm, 1000 µm, and 1500 µm temporal to the fovea (T500, T1000, T1500). Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were measured with a mercury sphygmomanometer. Only the right eye values were used for statistical comparisons between the groups.

Results

Mean age was 23.8 ± 2.8 years in hypertensive subjects and 23.5 ± 2.1 years in the control group (p = 0.945). All choroidal thickness measurements (mean choroidal thickness, subfoveal choroidal thickness, all nasal and all temporal choroidal thicknesses) were significantly lower in hypertensive subjects (p<0.001 for subfoveal, N500, T500, T1000, T1500; p = 0.001 for N1000; and p = 0.012 for N1500). The correlations between choroidal thickness measurements and blood pressure (SBP, DBP, MAP) were insignificant (p>0.05 for all correlations). Choroidal thickness measurements were also insignificantly correlated with disease duration (p>0.05 for all correlations).

Conclusions

The results of this study demonstrated that choroidal thickness decreases in patients with systemic arterial hypertension. This may be caused by arteriolar sclerosis and vascular contraction caused by high intravascular pressure in the choroid.
Changes in Choroidal Thickness and Corneal Parameters in Diabetic Eyes
Authors: Galgauskas Saulius , Laurinavičiūtė Guoda , Norvydaitė Dovilė , Stech Simona , Ašoklis Rimvydas
Published: October 2015

Purpose

To evaluate the effect of diabetes mellitus (DM) on central corneal thickness (CCT), corneal endothelial parameters (endothelial cell density [ECD], average size [AVE], hexagonality [A6], polymegathism [SD]), and subfoveal choroidal thickness (SFCT), and to determine whether these parameters depend on the duration of DM and hemoglobin A1c (HbA1c) level.

Methods

A total of 62 patients with type 2 DM and 65 healthy subjects were examined using a noncontact specular microscope, A-scan ultrasound, and spectral-domain optical coherence tomography. The study parameters included medical history, age, eye axial length, CCT, ECD, AVE, A6, SD, and SFCT. The duration of DM and HbA1c level of the 2 latest tests were noted.

Results

The SFCT (258.0 ± 74.4 µm) and ECD (2721.8 ± 264.1 cells/mm2) were significantly lower, and the CCT (566.7 ± 35.7 µm) higher, in diabetic patients than in the control group (313.1 ± 88.5 µm, 2967.3 ± 220.6 cells/mm2, 550.0 ± 56.4 µm, respectively) (p<0.05). There were no differences in age, sex, or axial length between the diabetic and control groups (p>0.05). Diabetic retinopathy and macular edema did not influence SFCT significantly (p>0.05). No differences in endothelial parameters between groups and no correlations among HbA1c, duration of DM, and any of the examined parameters were found (p>0.05).

Conclusions

Diabetic patients have thicker corneas, lower ECD, and thinner subfoveal choroid than healthy subjects.
The Clinical Utility of Measuring the Macular Outer Retinal Thickness in Patients with Glaucoma
Authors: Kita Yoshiyuki , Anraku Ayako , Kita Ritsuko , Goldberg Ivan
Published: October 2015

Purpose

Few optical coherence tomography (OCT) studies have investigated outer retinal thickness including the photoreceptor layer in glaucoma. We measured changes in the macular outer retinal thicknesses using OCT in patients with glaucoma with an average follow-up of 2.9 ± 0.8 years.

Methods

A total of 39 eyes of 39 patients with primary open-angle glaucoma were analyzed. The RTVue-100 was used to measure the macular outer retinal, macular ganglion cell complex, and circumpapillary retinal nerve fiber layer thicknesses, global loss volume, and focal loss volume. Using the paired t test, baseline parameters were compared with those at the last follow-up.

Results

The average baseline mean deviation value in the Humphrey Field Analyzer was −2.13 dB. The ganglion cell complex thickness significantly decreased over the follow-up period (baseline thickness, 79.66 ± 7.71 μm; final thickness, 76.79 ± 7.39 μm; p<0.001). There were significant differences between baseline and final visit measurements for circumpapillary retinal nerve fiber layer thickness, global loss volume, and focal loss volume (p<0.001, p<0.001, and p = 0.004, respectively). However, there was no significant change in outer retinal thickness (baseline thickness, 167.56 ± 7.26 μm; final thickness, 167.25 ± 7.93 μm; p = 0.540).

Conclusions

Outer retinal thickness was not altered during the follow-up period. The stability of outer retinal thickness may indicate the reliability of OCT analysis for glaucoma follow-up.
Sudden Occurrence of Roth Spots and Retinal Hemorrhages following Endoscopic Adhesiolysis: An SD-OCT Evaluation
Authors: Dell'Arti Laura , Barteselli Giulio , Pinna Valentina , Invernizzi Alessandro , Mapelli Chiara , Viola Francesco
Published: October 2015

Purpose

To document the occurrence of Roth spots and retinal hemorrhages by spectral-domain optical coherence tomography (SD-OCT) following endoscopic adhesiolysis for failed back surgery syndrome.

Methods

Case report.

Results

A 47-year-old patient noted progressive and bilateral visual loss immediately after epidural endoscopy and endoscopic adhesiolysis. Funduscopic examination showed multiple Roth spots and retinal hemorrhages at the posterior pole and the retinal midperiphery in both eyes. Spectral-domain optical coherence tomography demonstrated that Roth spots involved the inner retina, while dot hemorrhages involved the outer retina. Most retinal hemorrhages and Roth spots resolved over 6 weeks, with complete functional recovery in both eyes. However, SD-OCT revealed multiple areas of disruption of the outer retinal layers in the left eye.

Conclusions

Roth spots and retinal hemorrhages can occur after endoscopic spinal surgery. Although hemorrhages resolve quickly over few weeks, SD-OCT can demonstrate that retinal damage might persist, especially in the outer retina. This finding may explain cases of incomplete recovery of visual function after complicated endoscopic adhesiolysis.
Intravitreal Injection of Recombinant Tissue Plasminogen Activator in Submacular Hemorrhage: Case Series
Authors: Araújo Joana , Sousa Cristina , Faria Pedro Alves , Carneiro Ângela , Rocha-Sousa Amândio , Falcão-Reis Fernando
Published: October 2015

Purpose

To report the safety and efficacy of intravitreal recombinant tissue plasminogen activator (rtPA) with gas for managing submacular hemorrhage.

Methods

Patients with submacular hemorrhage centered in or close to the fovea underwent hemorrhage displacement with intravitreal injection of rtPA (50 μg/0.05 mL) followed by gas injection (0.3 mL SF6). Anatomic and visual outcomes are described.

Results

Exudative age-related macular degeneration (AMD) (n = 4) and blunt trauma (n = 2) were the etiologies of submacular hemorrhage in this sample. Intravitreal injection of rtPA decreased the extent of submacular hemorrhage in all eyes, with complete hemorrhage displacement in 2 and partial displacement in 4. Visual acuity remained stable (n = 4) or improved (n = 2) after the procedure. Improvements in anatomic and visual outcomes were less evident in exudative AMD cases, which also had longer hemorrhage duration. Recurrence occurred only in 1 eye. No evident rtPA-associated retinal toxicity was observed.

Conclusions

Untreated submacular hemorrhage has poor visual prognosis. Our results suggest that rtPA injection is a minimally invasive, simple, inexpensive procedure with few related complications. Cost-benefit of this injection seems acceptable.
Receiver Operating Characteristic Curve to Predict Anti-VEGF Resistance in Retinal Vein Occlusions and Efficacy of Ozurdex
Authors: Wolfe Jeremy D. , Shah Ankoor R. , Yonekawa Yoshihiro , Faran Abdulrahman Al , Franklin Michael S. , Abbey Ashkan M. , Capone Antonio
Published: October 2015

Purpose

Current treatment paradigms for macular edema associated with retinal vein occlusions (RVO) often involve initial treatment with anti-vascular endothelial growth factor (VEGF) agents, then switching to intravitreal dexamethasone implant (IDI; Ozurdex, Allergan, Parsippany, NJ) for poor responders. However, many patients undergo multiple injections prior to being declared a nonresponder. We devised a method for prediction of poor anti-VEGF response after one injection, and show that these patients subsequently respond well to IDI.

Methods

This study is a retrospective consecutive interventional case series of patients with RVO receiving anti-VEGF agents that were switched to IDI. Patients were categorized as nonresponders to anti-VEGF agents (edema did not improve) or responders (edema improved, but switched to IDI for longer treatment duration). Receiver operating characteristics (ROC) curve analysis was used to determine cutoffs of reduction in central retinal thickness (CRT) to predict poor response to anti-VEGF treatment.

Results

Twenty-three patients met inclusion criteria. There were 14 nonresponders and 9 responders. The ROC curve analysis found that the maximal sensitivity and specificity in correctly identifying responders to anti-VEGF therapy was those with >25% reduction in CRT 1 month after 1 anti-VEGF treatment (sensitivity 0.89, specificity 0.79, area under the curve 0.93). After IDI placement, anti-VEGF nonresponders showed significant improvement in visual acuity (VA) (p = 0.02) and CRT (p = 0.01).

Conclusions

In patients with macular edema secondary to RVOs, a reduction in CRT by ≤25%, 1 month after 1 anti-VEGF injection, is predictive of poor response to anti-VEGF treatment. These patients may benefit from earlier conversion to IDI treatment, which in our study, resulted in improved VA and CRT.
Metal Ion Levels in Ceramic-on-Ceramic THR with Modular Necks: Analysis of Cobalt and Chromium Serum Levels in 30 Healthy Hip Patients
Authors: Somers Jan F.A.
Published: October 2015

Background

Modular necks in total hip replacement (THR) can be a source of metal ion release. There are no data to date on the level of cobalt and chromium ions in the serum of patients with a cobalt-chrome stem and a titanium modular neck.

Methods

Serum ion levels were measured in healthy volunteers with a well-functioning ceramic-on-ceramic THR.

Results

Average cobalt in serum was 1.21 µg/l for unilateral THR and 2.2 µg/l for bilateral THR. No patient had cobalt levels higher than 2.4 µg/l. No patient had measurable chromium levels. There were no differences in cobalt levels for hips with short necks versus hips with long necks.

Conclusions

The hybrid THR Profemur® Xm – Procotyl® L with a titanium modular neck on a cobalt-chrome stem design shows no signs of abnormal toxic ion levels (cobalt or chromium) in a randomly selected group of well-functioning hip patients.
Patients’ Perception of Leg Length Discrepancy Post Total Hip Arthroplasty
Authors: Sykes Alice , Hill Janet , Orr John , Humphreys Patricia , Rooney Aidan , Morrow Esther , Beverland David
Published: October 2015

Perception of a leg length discrepancy post total hip arthroplasty (THA) is one of the most common sources of patient dissatisfaction and can have a direct influence on the considered success of the operation.

This research examined postoperative perception of imposed limb discrepancies in a group of THA patients compared to a group of participants with no previous hip surgery. Two subgroups of THA patients were involved: those who did not perceive a difference in limb length following THA and those that did.

Discrepancies were imposed in 2.5 mm increments. For discrepancies ≥5 mm, a significant number of participants were aware of a difference (74%). There was no significant difference in perception of imposed discrepancies between THA patients and participants with no previous hip surgery. THA patients who perceived a difference in their limb lengths postoperatively had significantly worse pain and oxford scores when compared to THA patients who perceived their limb lengths to be equal.

Knowing the boundaries between LLDs that go undetected and those that patients are aware of could guide surgeons when evaluating the balance between correct soft tissue tension and the resulting unequal leg length. From these findings, discrepancies >5 mm are likely to be perceived. Whether this perception would lead directly to a negative outcome score and patient dissatisfaction is more complex to project and likely to be patient specific. Intraoperative methods to aid the controlled positioning of implanted components could help maintain and restore leg length to within an acceptable amount that patients cannot perceive.
Late Complications and Long-Term Outcomes following Aseptic Revision of a Hip Arthroplasty Performed for Oncological Resection
Authors: Houdek Matthew T. , Wagner Eric R. , Wilke Benjamin K. , Wyles Cody C. , Taunton Michael J. , Sim Franklin H.
Published: October 2015

Purpose

In order to achieve an oncological margin during limb salvage surgery for tumours around the hip, part or the entire hip joint is frequently sacrificed. Hip arthroplasty restores a functional extremity and achieves limb salvage. Currently there is a paucity of data concerning the late complications, long-term survival, and the risks of re-revision following aseptic revision of a total hip arthroplasty (THA) performed following an oncological resection.

Methods

We identified 78 patients who underwent aseptic revision of a THA which was performed for an oncological process involving the hip from 1972 to 2006. All patients had a minimum 5 years of follow-up with a mean of 13 years. Outcomes were compared to 1,378 patients undergoing aseptic revision of a THA that was performed for a diagnosis of osteoarthritis.

Results

The mean 5-, 10-, 15-, and 20-year re-revision-free survival for an oncologic process of the hip was 100%, 85%, 69%, and 57%. Within this cohort, younger patients were at an increased risk of revision surgery. There was no difference in survivorship of the revision implant at any of the aforementioned time points between the oncologic and osteoarthritis cohorts. Patients with an oncologic diagnosis had a higher rate of dislocations, component wear, and loosening compared to the osteoarthritis group.

Conclusion

Late complications following revision surgery of THA performed for an oncologic resection are common. The results of this study provide information for counselling patients on implant survivorship and complications following aseptic revision THA after index surgery for an oncologic indication.
Vulvar Necrosis after Surgical Treatment of Femoral Neck Fracture: A Case Report and Investigation of the Mechanism of Injury
Authors: Chantalat Elodie , Debonnecaze Guillaume , Cavaignac Etienne , Chaynes Patrick , Vidal Fabien
Published: October 2015

We report the case of a young patient, presenting with total bilateral vulvar necrosis after reduction of a femoral neck fracture. This report describes the management of this complication, its mechanism of injury and the associated means of prevention.

We present an investigation of the vulvar vasculature in order to understand the mechanism of injury.

The study of the vulvar vasculature rejects the anatomical hypothesis of selective damage to the internal and external arteries. Instead, it suggests intraoperative impingement of the terminal blood vessels caused by compression against the perineal post prompting discussion on the use of moulded countertraction posts during orthopaedic surgery.