bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental application of high‐frequency electric welding of biological tissues for iridoplasty and trabeculectomy
Authors: ZADOROZHNYY O , PASYECHNIKOVA N , NAUMENKO V , LAZAR Y 
Published: August 2012

AbstractPurpose To estimate the possibility of using of high‐frequency electric welding of biological tissues for iridoplasty and trabeculectomy in the experiment.Methods In experiment we used devices and instruments made by the original method in the E.O.Paton Electric Welding Institute. Experimental studies in vitro were performed on the isolated porcine eye. After dissection of the iris edges of the cut combined with a bipolar instrument. In the second phase studied the possibility of using the method of high‐frequency electric welding (frequency ‐ 66 kHz ‐ 440 kHz) for trabeculectomy with monopolar electrode, which was injected into the anterior chamber through the corneal incision. The second electrode was fixed to the sclera with special clip. For experiment in vivo we used 10 chinchilla rabbits. Morphological studies of the samples were performed.Results We have observed the formation of solid welded connection of cut edges of the iris. In vitro trabecular tissue of the anterior chamber angle was removed using different settings. In vivo during iridoplasty observed minimal changes in the surrounding tissues in the area of electrical effects. It was also noted the formation of solid welded connection of iris edges. In vivo were removed structures of the anterior chamber angle of the rabbit without bleeding complications.Conclusion These results indicate the possibility of using the method of high‐frequency electric welding of biological tissues for microsurgery of the eye trabecular apparatus and iris. Requires further study of the characteristics of the developed method for working out the optimal parameters of exposure.
Ultrasonic circular cyclo coagulation in patients with primary open‐angle glaucoma: preliminary results of a multicenter clinical trial
Authors: APTEL F , DENIS P , ROULAND JF , NORDMANN JP , LACHKAR Y , RENARD JP , SELLEM E , BAUDOUIN C , BRON A 
Published: August 2012

AbstractPurpose To evaluate the efficacy and safety of the Ultrasonic Circular Cyclo Coagulation (UC3) procedure in patients with primary open‐angle glaucoma (POAG).Methods Prospective multicenter clinical trial. 39 eyes of 39 patients with POAG, intraocular pressure (IOP) > 21 mmHg, an average of 1.65 failed previous surgeries and an average of 3.2 hypotensive medications were insonified with a probe comprising 6 piezoelectric transducers. 18 patients (group 1) were treated with a 4 seconds exposure time for each shot and 21 patients (group 2) with a 6 seconds exposure time. Follow‐up visits were performed at 1 day, 1 week, 1, 2, 3, 6 and 12 months after.Results IOP was significantly reduced in both groups (p<0.05), from a mean preoperative value of 28.9 ± 6.8 mmHg in group 1 and 29.2 ± 6.9 mmHg in group 2 to a mean value of 18.1 ± 4.4 mmHg in group 1 and 16.1 ± 8,5 mmHg in group 2 at last follow‐up. Success (IOP reduction >20%) was achieved in 15 of 18 (83%) eyes of the group 1 with an average of IOP decrease of 42% and in 19 of 21 (90%) eyes of the group 2 with an average of IOP decrease of 49%. No major intra‐ or post‐operative complications occurred.Conclusion UC3 seems to be an effective and well‐tolerated method to reduce intraocular pressure in patients with POAG.
Commercial interest
Efficacy of pneumatic trabeculoplasty in patients with primary open angle glaucoma and ocular hypertension in combination with prostaglandin monotherapy
Authors: MARTY A , BECCAT S , AMARI E , NORDMANN JP , DENIS P 
Published: August 2012

AbstractPurpose To evaluate the safety and efficacy of pneumatic trabeculoplasty (PNT), a non invasive treatment to lower intraocular pressure (IOP), in patients with primary open angle glaucoma or ocular hypertension under prostaglandin monotherapy.Methods 38 patients were enrolled from may 2009 to october 2010 to determine the IOP lowering effects of PNT. All the eyes had been diagnosed primary open angle glaucoma (87%) or ocular hypertension. PNT was performed in one or both eyes at day 0, 7, 90 and 180. Assessments were peformed at day 0,7, 45, 90 and 180 including visual acuity, IOP by goldmann tonometer, slit lamp examination and optic disc evaluation. Safety was adressed at all visits. A 15% reduction of IOP defined responder patients.Results Mean IOP before PNT was 23.21 +/‐ 2,92 mmHg. 57 eyes were treated and analysed. All patients completed 6 months of follow up. After PNT, a statistically significant reduction of IOP occured at all visits: at days 7, 45, 90, 180, IOP was 19,92+/‐5,05, 19,32+/‐5,22, 18,89+/‐5,00, 17,76+/‐4,81 mmHg (p<0,05). The IOP decrease was up to 23,4% at day 180. The rate of responder patients was 54,4% after one week and 76,4% at day 180. After 6 months, 76% patients had IOP reduction more than 15%, 69% more than 20%, 51% more than 25% and 46% more than 30%. Side effects such as conjunctival hyperhaemia, subconjunctival hemorrhage and corneal epithelium disorder occured. No significant complications were observed.Conclusion PNT seems to be a safe technique allowing a significant IOP reduction with prostaglandin monotherapy. It could be helpful especially in patients having troubles in following their local treatment correctly.
Experimental glaucoma model using polyurethane microbeads in rats
Authors: KIM C , RHO S , LEE N , LEE C , KIM N , PARK S , CHOI B 
Published: August 2012

AbstractPurpose To establish a new experimental glaucoma model using intracameral injection with various microbeads of different sizes and materials.Methods Chronic elevation of intraocular pressure (IOP) was induced by unilateral microbeads injection into the anterior chamber of Sprague‐Dawley (SD) rats. The effectiveness of different materials (polymethylmethacrylate (PMMA, 7 and 15 µm), polyurethane (PU, 7 and 17 µm), Silica (13 µm)) on IOP elevation was compared. Reinjection of the microbeads was performed at post‐injection day 7. Difference of IOP between both eyes was observed for 4 weeks. Axonal degeneration was assessed by the analysis of light microscopic and transmission electron microscopic photos.Results Total 54 SD rats weighing 250~300g initially were included in this study. After a single injection, the ratio of increased IOPs (mean value) at post‐injection day 3 were 56.6 %, 24.1 %, 23.8 %, 98.1 %, and 153.0 % in PMMA 7 µm, PMMA 15 µm, PU 7 µm, PU 17 µm, and Silica 13 µm, respectively. Since inter‐animal variability of PU 17 µm injected group was smaller than others, so that it was more adequate to produce constant IOP elevation with good repeatability (whereas Silica injected eyes showed severe inflammation). Sustained elevation of IOP by twice of PU 17 µm injection for at least 4 weeks resulted in approximately a 25.5 % loss of axon density (p=0.023, Mann‐Whitney U test). No axonal damage was noted in safety study group.Conclusion These data supports that the polyurethane microbeads injection is an applicable and versatile model for high tension glaucoma in rats. Among several biomaterials, PU showed more stable IOP elevation with safety. Future studies about suitable size and biomaterial of microbeads are more needed to secure this novel model.
Experimental glaucoma model in two lines of rats using polystyren microspheres (Bead Model)
Authors: SMEDOWSKI A , PIETRUCHA‐DUTCZAK M , WYLEGALA E , LEWIN‐KOWALIK J 
Published: August 2012

AbstractPurpose The purpose of this study is to develop a method to get simple and reproducible rodent glaucoma model in rats of Wistar and Long‐Evans line. The intraocular pressure (IOP) and loss of number of retinal ganglion cells (RGCs) were measured to evaluate the success of model.Methods 20 male rats were used in this study. 7 of them were excluded because of incidence of eye inflammation. Finally 13 rats (6 Wistar rats and 7 of Long‐Evans lines with a mass about 200 g) were included. IOP was elevated by injection of polystyrene microbeads into the anterior chamber and measured by Icare TonoLab. For each rat, the right eye was treated with different combinations of polystyrene microspheres with a diameter of 6 and 1 um separately and the left eye was treated as a control. RGCs were labeled retrogradely with a fluorescent marker “FluoroGold” 5 days before euthanasia and after harvested and made slices for a counting of surviving ganglion cells.Results Mean intraocular pressure (IOP) of examined group was 24 mmHg ± 5,4. The highest IOP appeared after injection on 3rd day, and rose a bit lasting till 21st day. The mean IOP in contralateral eyes during experiment was 10,8 mmHg ± 0,5. Mean number of RGCs in eyes with elevated IOP was 3014±655 cells (semiquantitative method was used). In control group it was 4106±852 cells. In examined group values of IOP were significantly higher and number of RGCs was significantly lower according to control eyes.Conclusion“Bead model” method could be used to create rat model of glaucoma with stable increasd IOP. The different size microspheres could provide the IOP with the desired values.
Controlled pupilar miosis to improve mesopic visual function in drivers over 40 years old
Authors: NAVARRO VALLS J , RAMIREZ‐MERCADO G , PEREZ‐CARRASCO MJ , LOBATO‐RINCON LL , CHAMORRO E , SANCHEZ‐RAMOS C 
Published: August 2012

AbstractPurpose To evaluate the influence of a diffuse illumination device located outside the field of vision that provokes a controlled pupillar miosis, on the visual acuity and contrast sensitivity in drivers tested in mesopic conditionsMethods Cross‐sectional prospective observational study in which visual Acuity 100% and 20% contrast by ETDRS Test (VA100 and VA20) and Contrast Sensitivity by Pelli‐Robson Test (CS) were evaluated in 39 drivers individuals under 40 years old and 30 drivers over 40. The study was carried out in a simulated setting for night driving with and without the interposition of the diffuse illumination deviceResults In individuals aged over 40 years, an statistically significant improvement of visual function was exhibit. Baseline visual acuity and contrast sensitivity scores were: VA100=0.02±0.18logMAR, VA20=0.21±0.2logMAR, and CS=0.62±0.32, whereas values for the interposition of diffuse illumination device were: VA100=‐0.03±0.14logMAR(p=0.02), VA20=0.19±0.17logMAR(p=0.3), and CS=0.76±0.33(p=0.0003). On the other hand, in drivers aged under 40, statistically significance was not found. In this condition, baseline visual function was: VA100=‐0.1±0.11logMAR, VA20=0.13±0.19logMAR, and CS=1.06±0.2, whereas the interposition of the mentioned system showed the following values: VA100=0.01±0.09logMAR(p=0.9), VA20=0.09±0.14logMAR(p=0.3), and CS=1.08±0.16(p=0.6)Conclusion Using diffuse illumination device in the interior of the vehicle, provides significant improvement in both high contrast visual acuity and contrast sensitivity in the group older than 40 years
Changes in contrast sensitivity perception due to protector screens for welding tasks: conventional protective optical filter vs novel protective optical filter of selective absorbance
Authors: BONNIN ARIAS C , AGUIRRE‐VILACORO V , CHAMORRO E , LOBATO‐RINCON LL , LANGA‐MORAGA A , NAVARRO‐VALLS J , SANCHEZ‐RAMOS C 
Published: August 2012

AbstractPurpose To evaluate differences in contrast sensitivity perception in central visual field using protective optic filters for welding tasks. Two interposed filters are compared: a conventional protective optical filter and a new protective optical filter with selective absorption designed by University Complutense of Madrid (UCM).Methods 36 people of working‐age were included in a cross‐sectional prospective observational study. Contrast sensitivity threshold in central visual field was evaluated using FDT Perimeter, C‐20 procedure (Humphrey systems, USA). Three conditions were set: a) without optical filters; b) with an interposition of conventional protective optical filter for welding (shade 2.5) and c) with an interposition of a novel protective optical filter of selective absorbance that fully blocks the short wavelength light and minimally attenuates the remaining bands of the visible spectrum.Results Contrast sensitivity in all visual field areas evaluated diminished 91‐98% with the conventional protective optical filters. UCM optical filters provoked a low‐level decrease in contrast sensitivity (9‐19%). Mean contrast sensitivity thresholds were 29.5±5dB, 25.5±4dB, 1.8±2dB in conditions a, b and c respectivelyConclusion Conventional optical filters resulted in drastically diminished contrast sensitivity. UCM optical filter minimally diminish the visual function, allowing a suitable visibility and also maintaining an appropriate level of protection against phototoxic damage.
Morphometrical indices in acquired myopia
Authors: BOYCHUK IRYNA , GORBATUK TL 
Published: August 2012

AbstractPurpose On an etiology myopia can be congenital and acquired (school myopia), and on character of development – stable and progressing. According to experimental works (Ai L, Li J, Guan H, Wildsoet CF,2009, Nickla DL, Wildsoet CF, Troilo D., 2002) it is known, that the thickness of a retina varies at eyeball growth, and also at defocus change. The probability of myopia growth in each patient remains difficult to predict. The purpose was to reveal differences in patients with acquired myopia and divide them on studied indicesMethods A child of 7‐15 years old (53) with myopia were observed, a criterion of inclusion in research was acquired myopia. Parameters which were studied: visual acuity, refraction, axis length of an eye, accommodation reserves, intraocular pressure, retina layer thickness and peripapillary fiber layer thickness, optic nerve disk indices by optical coherent tomography under standard protocols by SOCT Copernicus, Optopol Technology Sp.z o.o., PolandResults Optimum points of division of acquired myopia on stable and progressing were established by ROC analysis. The discriminate analysis with high reliability has shown, that the progressing form of myopia will be observed in children with average thickness in a zone 3mm more than 246,3mk , with a refraction more than 4,5 dptr and axes more than 25,3mm (Р=0,0001). Fisher's discriminating functions are defined and the equations for definition of the stable and progressing forms of acquired myopia are offered. Effect of classification is 80,3%.Conclusion Results have allowed to offer model of classification for the stable and progressing forms of myopia on morfometric indices, axis length and refraction in patients with acquired myopia
Spatial tuning affects diagnostic efficacy of pseudoisochromatic plates
Authors: KRASTEL H , KALTAKJI F , LEERS S , JERCHEL N , JONAS JB 
Published: August 2012

AbstractPurpose To demonstrate that the diagnostic efficacy of pseudoisochromatic plates is reduced by oversized and by undersized angles of observation.Methods Pseudoisochromatic “C” and “E” plates accounting for equal demands on color vision in repeated exams were presented to 7 daltonian and 10 normal observers. An illuminant D 65 source (Unity Color Light2go) rendered 170 cd/m2 of luminance. The standard viewing time was 3 s, the viewing angles were 33.4°, 7.4° and 1.8°.Results Daltonians failed to recognize the plates at 7.4° of visual angle which correspondes to the recommended standard viewing distance. At a viewing angle of 33.4° the plates were recognized by 4 of 7 Daltonians. At a viewing angle of 1.8° the plates were recognized by 3 of 7 Daltonians. With 1.8° of viewing angle, normal observers claimed fusion of i) those various pseudoisochromatic picture elements which are on the red side of yellow, and of ii) those various elements which are on the green side.Conclusion A standardized observation distance (0,7 m) is necessary for pseudoisochromatic plates, as recommended by Ishihara and Velhagen. At small viewing angle, antagonistic processing of colored picture elements is impaired, causing loss of optotype camouflage. At large viewing angle, individual elements may activate weak color opponent mechanisms in a daltonian retina where green cones or red cones are scarce but not entirely lacking. Poster visitors may observe spatial tuning within their own color vision.
Commercial interest
Vision in subjects with hyperawareness of afterimages and “visual snow”
Authors: ALISSA R , BI W , BESSERO AC , PLANT G , BARBUR JL 
Published: August 2012

AbstractPurpose Some patients complain of persisting visual noise, often described as “visual snow” (VS) and / or prolonged afterimages, but show no obvious clinical abnormalities. The purpose of this study was to examine the extent to which the processing of different stimulus attributes remains normal in VS patients.Methods Seven VS patients and nine control subjects were examined. Advanced vision and optometric tests were used to assess visual acuity (VA), red / green (RG) and yellow / blue (YB) colour sensitivity, rapid flicker sensitivity, chromatic afterimage strength and duration and pupil response amplitudes and latencies to chromatic stimuli.Results The VS patients exhibited normal VA, colour and rapid flicker sensitivity and chromatic afterimage strength. Both controls and four of the VS patients exhibited pupil constrictions to the onset of the coloured stimulus, followed by recovery during the stimulus and a further constriction at stimulus offset, normally attributed to perception of chromatic afterimages (Prog.Brain Res. 144:243‐259, 2004). The pupil responses in three of the VS patients lacked the rapid recovery phase following the initial constriction to stimulus onset.Conclusion The absence of recovery following the initial constriction of the pupil in three of the VS patients deviates from normal responses and suggests the presence of a more sustained retinal afferent signal that drives the pupil response. The latter may be linked to differences in retinal processing of visual signals that cause the perception of visual snow when the coloured stimulus is viewed against a uniform background.
Detection of colour signals in objects defined by luminance contrast
Authors: HICKEY J , RODRIGUEZ‐CARMONA M , BARBUR JL 
Published: August 2012

AbstractPurpose The aim was to compare chromatic detection thresholds using two methods that are often employed to isolate the use of colour signals: a. Colour thresholds measured in dynamic luminance contrast (LC) noise when a spatially structured object is defined only by colour signals b. Thresholds for detection of colour changes in objects defined by luminance contrast (i.e., the luminance pedestal (LP) technique that is often used in visual psychophysics to isolate the use of colour signals) Earlier findings in patients with cerebral achromatopsia (Proc.R.Soc.Lond.B. 258 :327‐334 (1994)) suggest that different neural mechanisms handle the use of colour signals in the two conditions. It is therefore of interest to establish whether the corresponding colour thresholds in (a) and (b) are also different in normal subjects.Methods Colour detection thresholds were measured using both LP and LC noise methods for discrete LP contrast levels and background luminances. The same four‐alternative, forced‐choice staircase procedure was used to measure thresholds for every combination of target and background luminance.Results The amplitude of dynamic LC noise does not affect colour thresholds. In general, technique (a) yields smaller thresholds when compared to the LP technique (b) for all pedestal LC levels and background luminances. Negative luminance contrast pedestals yield increased colour thresholds for both the red/green and yellow/blue axes.Conclusion When chromatic signals are added to objects defined by negative luminance contrast, the corresponding colour thresholds are no longer processed independently and increase monotonically with luminance contrast.
Normal range of Cambridge low contrast grating test: a population based study
Authors: OSTADIMOGHADDAM H , YEKTA AA , HERAVIAN J , AZIMI A , KHABAZKHOOB M , MOHAMMADIAN M 
Published: August 2012

AbstractPurpose To determine the normal range of contrast sensitivity in a representative sample of the population of Mashhad, Iran, and its determinantsMethods In this report, Contrast Sensitivity (CS)c data of 2449 out of 3213 selected individuals was analyzed. CS was determined using Cambridge low contrast squarewave grating and to evaluate its determinants, age, gender, Visual Acuity (VA) and Spherical Equivalent (SE) were analyzed.Results The mean age of the participants was 29.1±17.3 years (range: 4‐89 years) and 66.4% of them were female. The score of CS for the right and the left eye and its binocular score were 239.6±233.3, 234.6±228.6 and 310.9±249.0 cps, respectively. Multiple linear regression showed that CS significantly correlated with age (β=‐1.1,P<0.001), gender (β=‐40.1, P<0.001), LogMAR BCVA (β=‐165.4, P<0.001) and SE(β=10.2, P<0.001)Conclusion Since our study was population‐based, normal range of Cambridge low contrast grating test can be used as a reference guide in a general population. Our findings can be used in both research and clinic, especially evaluation of the results of refractive surgeries. However, in clinical evaluations, it should be noted that the mean CS is lower in older, myopic individuals who have a lower BCVA.
Evidence of neuroplasticity in the human visual cortex following beneficial anti‐VEGF treatment in exudative age‐related macular degeneration
Authors: VOTTONEN P , PÄÄKKÖNEN A , TARKKA I , KAARNIRANTA K 
Published: August 2012

AbstractPurpose Anti‐vascular endothelial growth factor (VEGF) agents have been shown to improve visual acuity and prevent vision loss in exudative age‐related macular degeneration (AMD). As the vision improves relatively quickly in response to intravitreal injections, we wanted to know whether this improvement is reflected in electrophysiolocal markers of visual cortical processing.Methods Our interventional case series included 6 elderly patients who underwent injection treatment to the affected eye. Their visual acuity, tomographic images of retinal thickness and visual evoked potentials (VEP) were assessed before of the treatment and six weeks after the last injection.Results All patients showed improved visual acuity and reduced retinal fluid after the treatment. All but one patient showed increased VEP P100 component amplitudes and/or shortened latencies in the treated eye. These VEP changes were consistent with improved vision while the untreated eyes showed no changes.Conclusion Our results indicate that anti‐VEGF injections improved visual function of the treated eyes both in the level of the retina and in level of visual cortical processing.