Herndon, VA, United States

Applied Visual Sciences

Herndon, VA, United States
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Sato T.,Applied Visual Sciences | Wada K.,Osaka University | Arahori H.,Osaka University | Kuno N.,Santen Pharmaceutical | And 4 more authors.
American Journal of Ophthalmology | Year: 2012

Purpose: To determine the serum concentrations of bevacizumab and vascular endothelial growth factor (VEGF) in infants with retinopathy of prematurity (ROP) who received intravitreal bevacizumab; and to determine whether the changes in the serum concentration of bevacizumab were significantly correlated with the serum concentration of VEGF after intravitreal bevacizumab. Design: Case series. Methods: Eleven infants (4 girls and 7 boys) with ROP were studied. They received 0.25 mg or 0.5 mg of intravitreal bevacizumab to either 1 eye (unilateral cases) or both eyes (bilateral cases) with vascularly active ROP. Serum samples were collected before and 1 day, 1 week, and 2 weeks after the intravitreal bevacizumab. The serum concentrations of bevacizumab and VEGF were measured by enzyme-linked immunosorbent assay, and the correlation in the serum levels between the 2 was determined. Results: The serum concentration of bevacizumab before and 1 day, 1week, and 2 weeks after a total of 0.5 mg of intravitreal bevacizumab was 0 ng/mL, 195 ± 324 ng/mL, 946 ± 680 ng/mL, and 1214 ± 351 ng/mL, respectively. The serum bevacizumab level before and 1 day and 1 week after a total 1.0 mg of intravitreal bevacizumab was 0 ng/mL, 248 ± 174 ng/mL, and 548 ± 89 ng/mL, respectively. The serum concentration of VEGF before and 1 day, 1 week, and 2 weeks after a total of 0.5 mg intravitreal bevacizumab was 1628 ± 929 pg/mL, 427 ± 140 pg/mL, 246 ± 110 pg/mL, and 269 ± 157 pg/mL, respectively. There was a significant negative correlation (r = -0.575, P =.0125) between the serum concentration of bevacizumab and VEGF when a total of 0.25 mg or 0.5 mg of bevacizumab was injected. Conclusions: These results indicate that bevacizumab can escape from the eye into the systemic circulation and reduce the serum level of VEGF in infants with ROP. Continued extensive evaluations of infants are warranted for possible effects after intravitreal bevacizumab in ROP patients. © 2012 Elsevier Inc. All rights reserved.

Polizzi S.,University of Florence | Fujikado T.,Applied Visual Sciences
Optometry and Vision Science | Year: 2016

Purpose To report a case of transient loss of accommodation after laser photocoagulation for peripheral retinal tear. Loss of accommodation is one of the lesser known and less common complications of peripheral retinal laser photocoagulation. In fact, only a few works concerning this issue have been published so far. Deficit of accommodation has been described only after extensive laser treatment of the peripheral retina. To the best of our knowledge, this is the first case that reports this complication after treatment limited to a small retinal area. We discuss the possible pathogenetic mechanism of this phenomenon. Case Report A 25-year-old healthy myopic woman came to the eye clinic for flashes and floaters in her right eye. Fundus evaluation revealed a small horseshoe retinal tear at the 6 o'clock position. She was treated with prophylactic retinal laser barrage in the right eye. Twelve days later, she returned to our Retinal Clinic because of difficulty with near vision. The problem started soon after the laser procedure. On examination, her distance visual acuity was 20/20 wearing her glasses. The patient could read J1+ at 33 cm with the left eye and required a +3.00D addition over her corrective lens to read J1+ with the right eye. The accommodative disturbance resolved itself spontaneously and gradually within 3 months of laser treatment. Conclusions We believe that transient loss of accommodation, although rare, should be included during pretreatment discussion with young patients regarding the possible side effects of laser photocoagulation, even if this is limited to a small area of the peripheral retina. © 2015 American Academy of Optometry.

Leahy C.,National University of Ireland | Leroux C.,National University of Ireland | Dainty C.,National University of Ireland | Diaz-Santana L.,Applied Visual Sciences
Optics Express | Year: 2010

Microfluctuations of accommodation have been the subject of many studies. New technological developments now permit us to study the dynamics of the microfluctuations with unprecedented resolution and accuracy. We aim to characterise their temporal statistics for different levels of accommodative effort, using a custom-built aberrometer. We conducted 46 s long measurements on the dominant eye of 9 young, healthy subjects. The ocular wavefront was sampled every 250 μm across the 3.9 mm measured pupil, at a frame rate of 173 Hz. This enabled us to obtain high resolution estimates of the Power Spectral Density (PSD). Results show that the shape of the estimated PSD for a 4 D effort is distinct from the shape for the two extrema of the accommodation range. The autocorrelation function of the increments of the accommodation signal is also affected by the level of effort, regardless of the refractive error of the subject. © 2010 Optical Society of America.

Morimoto T.,Applied Visual Sciences | Kanda H.,Applied Visual Sciences | Kondo M.,Mie University | Terasaki H.,Nagoya University | And 2 more authors.
Investigative Ophthalmology and Visual Science | Year: 2012

PURPOSE. To determine whether transcorneal electrical stimulation (TES) has neuroprotective effects on the photoreceptors, and whether it slows the rate of decrease of the electroretinogram (ERG) in rhodopsin P347L transgenic (Tg) rabbits. METHODS. Six-week-old Tg rabbits received TES through a contact lens electrode on the left eye weekly for 6 weeks. The right eyes received sham stimulation on the same days. Electroretinograms (ERGs) were recorded before and at 12 weeks after the TES. After the last ERG recordings, the animals were euthanized for morphologic analysis of the retinas. Immunohistochemical (IHC) analysis was performed to detect the immunostaining by peanut agglutinin (PNA) and rhodopsin antibodies in the retinas. RESULTS. The a- and b-wave amplitudes of the photopic ERGs and the b-wave amplitudes of the scotopic ERGs at higher stimulus intensities were significantly larger in the TES eyes than in the sham stimulated eyes (P < 0.05, respectively). Morphologic analyses showed that the mean thickness of the outer nuclear layer (ONL) in the visual streak at 12 weeks was significantly thicker in TES eyes than in sham-stimulated eyes (P < 0.05). IHC showed that the immunostaining by PNA and rhodopsin antibody in the TES-treated retinas was stronger than that in the sham-stimulated retinas. CONCLUSIONS. TES promotes the survival of photoreceptors and preserves the ERGs in Tg rabbits. Although further investigations are necessary before using TES on patients, these findings indicate that TES should be considered for therapeutic treatment for RP patients with a P347L mutation of rhodopsin.

Fujikado T.,Applied Visual Sciences
Clinical Ophthalmology | Year: 2014

Methods: Three types of IOL holders were prepared. The first was without decentration or tilt, the second had a decentration of 0.5 mm, and the third had a tilt of 5.0°. One spherical IOL and three aspherical IOLs, each with a power of +20 D, were set in the holders and their optical properties (wave front aberration, defocused modulation transfer function, defocused point spread function, and Landolt ring simulations) were compared.Results: Coma aberrations generated by misaligned IOLs were related to the spherical aberration corrective power of the IOLs. Landolt ring simulations show that the depth of focus increased as spherical aberration increased and that the retinal image quality was degraded by increases in coma aberration.Conclusion: Coma aberration was generated by IOLs with a large degree of spherical aberration correction, leading to reduced retinal image quality when the IOL was misaligned. This suggests that, in a clinical setting, the quality of vision might be improved by reducing the degree of coma aberration using IOLs that retain, or minimally correct, spherical aberration.Purpose: To examine the effect of misalignment (decentration and tilt) of intraocular lenses (IOLs) on retinal image quality using a water-immersed model eye with corneal spherical aberration adjusted to the values found in normal human eyes (spherical aberration 0.25 μm; pupil diameter 6 mm). © 2014 Fujikado and Saika.

Sato T.,Applied Visual Sciences | Shima C.,Osaka University | Kusaka S.,Applied Visual Sciences
American Journal of Ophthalmology | Year: 2011

Purpose To determine the vitreous levels of angiopoietin (Ang)-1 and Ang-2 in eyes with retinopathy of prematurity (ROP), and to determine the correlation between the 2 levels. Design Retrospective case-control study. Methods Forty-eight eyes with stage 4 ROP were studied. Six eyes with congenital cataract were used as controls. The ROP eyes were classified by the vascular activity into highly (n = 22), moderately (n = 15), and mildly (n = 11) vascular-active ROP. Eyes with highly vascular-active ROP initially received 0.5 mg of intravitreal bevacizumab (IVB) and underwent vitrectomy within 1 week. The others underwent vitrectomy without IVB. Vitreous samples were collected at the beginning of vitrectomy, and the vitreous levels of Angs were measured by enzyme-linked immunosorbent assay. Results The mean concentrations of Ang-1 and Ang-2 were 201.9 and 7832.1 pg/mL in highly vascular-active ROP eyes, 216.1 and 7731.2 pg/mL in moderately vascular-active ROP eyes, 533.8 and 1685.9 pg/mL in mildly vascular-active ROP eyes, and 0 and 41.5 pg/mL in control eyes. The vitreous Ang-1 level was significantly higher (P < .05) in highly, moderately, and mildly vascular-active ROP eyes than in control eyes. The vitreous Ang-2 level was significantly higher (P < .05) in highly and moderately vascular-active ROP eyes than in control eyes. There was a significant negative correlation (r = -0.406; P = .040) between the Ang-1 and Ang-2 levels in moderately and mildly vascular-active ROP eyes. Conclusions The balance of Ang-1 and Ang-2 in the vitreous may be important in the pathogenesis of ROP. © 2011 Elsevier Inc.

Morimoto T.,Applied Visual Sciences
International Review of Neurobiology | Year: 2012

Neurons of the central nervous system (CNS) of adult mammals can be damaged in a variety of ways. Most neurons rapidly die after injury. Even if the injured CNS neurons do not die in a short time, the neurons eventually die because they are not able to regenerate their axons to reconnect with their normal targets. In addition, neurons are normally not replaced. Therefore, much work has been directed toward understanding of the molecular regulation of the CNS degeneration following injury, and different experimental strategies are being used to try to protect the damaged neurons. Following axonal lesion, the neurons not only need to survive but also to reconnect to be functionally relevant, and efforts are directed toward not only survival but also axonal regeneration and proper rewiring of injured neurons. Recent experimental data suggest that electrical activity, endogenous or exogenous, can enhance neuronal survival and regeneration in vitro and in vivo. This chapter reviews the evidence that have been obtained on the role of neuronal electrical activity on neuroprotection. We will develop perspectives toward neuroprotection and regeneration of adult lesioned CNS neurons based on electrical activity-dependent cell survival that may be applicable to various diseases of the CNS. © 2012 Elsevier Inc.

Morimoto T.,Osaka University | Miyoshi T.,Osaka University | Sawai H.,Osaka University | Fujikado T.,Applied Visual Sciences
Experimental Eye Research | Year: 2010

We previously showed that transcorneal electrical stimulation (TES) promoted the survival of axotomized retinal ganglion cells (RGCs) of rats. However the relationship between the parameters of TES and the neuroprotective effect of TES on axotomized RGCs was unclear. In the present study, we determined whether the neuroprotective effect of TES is affected by the parameters of TES. Adult male Wistar rats received TES just after transection of the left optic nerve (ON). The pulse duration, current intensity, frequency, waveform, and numbers of sessions of the TES were changed systematically. The alterations of the retina were examined histologically seven days or fourteen days after the ON transection. The optimal neuroprotective parameters were pulse duration of 1 and 2 ms/phase (P < 0.001, each), current intensity of 100 and 200 μA (P < 0.05, each), and stimulation frequency of 1, 5, and 20 Hz (P < 0.001, respectively). More than 30 min of TES was necessary to have a neuroprotective effect (P < 0.001). Symmetric pulses without an inter-pulse interval were most effective (P < 0.001). Repeated TES was more neuroprotective than a single TES at 14 days after ON transection (P < 0.001). Our results indicate that there is a range of optimal neuroprotective parameters of TES for axotomized RGCs of rats. These values will provide a guideline for the use of TES in patients with different retinal and optic nerve diseases. © 2009 Elsevier Ltd.

A system and method for improved detection of objects of interest in image data using adaptive stepwise classification and hierarchical decision diagrams to manage false positives is provided. The present invention uses an adaptive stepwise classification approach, preferably based on a hierarchical binary decision diagram (BDD), to enable the efficient management of false positive objects to improve detection performance. The present invention is particularly suited for the reduction of false positives during the detection of acid fast bacilli associated with tuberculosis.

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