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https://www.readbyqxmd.com/read/29331294/-study-of-the-results-scleral-fixated-intraocular-lenses-in-the-absence-of-capsular-support
#1
A Benarous, A Drimbea, S Milazzo
INTRODUCTION: In the absence of sufficient capsular support, scleral fixation of the intraocular lens is an interesting alternative. The goal is to evaluate this implantation technique when traditional implantation is impossible. PATIENTS AND METHODS: This is an observational, retrospective, monocentric study at the Amiens university medical center between August 2013 and March 2016. Patients all underwent scleral fixation of a three-piece implant without suturing of the haptics, after posterior vitrectomy...
January 10, 2018: Journal Français D'ophtalmologie
https://www.readbyqxmd.com/read/29331293/toric-lens-implantation-in-cataract-surgery-automated-versus-manual-horizontal-axis-marking-analysis-of-50%C3%A2-cases
#2
M Raucau, H El Chehab, E Agard, C Lagenaite, C Dot
SUBJECT: The main objective of our study was to evaluate the contribution of automated conjunctival registration in the alignment of toric intraocular lenses by comparing automated registration optimized with Callisto® to manual marking of the horizontal axis. MATERIALS AND METHODS: We performed a prospective, descriptive, monocentric study on patients undergoing cataract surgery with a toric intraocular lens (Asphina 709 Zeiss), performed by a surgeon with good experience in toric implants, between September 2016 and March 2017...
January 10, 2018: Journal Français D'ophtalmologie
https://www.readbyqxmd.com/read/29328285/astigmatic-laser-beams-with-a-large-orbital-angular-momentum
#3
Victor V Kotlyar, Alexey A Kovalev, Alexey P Porfirev
We show that an elliptic Gaussian beam, focused by a cylindrical lens, can be represented as a linear combination of a countable number of only even angular harmonics with both positive and negative topological charge. For the orbital angular momentum (OAM) of the astigmatic Gaussian beam, an exact expression is obtained in a form of a converging series of the Legendre functions of the second kind. It is shown that at some conditions only the terms with the positive or negative topological charge are remained in this series...
January 8, 2018: Optics Express
https://www.readbyqxmd.com/read/29328231/aberration-accounting-calibration-for-3d-single-molecule-localization-microscopy
#4
Clément Cabriel, Nicolas Bourg, Guillaume Dupuis, Sandrine Lévêque-Fort
We propose a straightforward sample-based technique to calibrate the axial detection in 3D single-molecule localization microscopy. Using microspheres coated with fluorescent molecules, the calibration curves of point spread function-shaping or intensity-based measurements can be obtained over the imaging depth range. This experimental method takes into account the effect of the spherical aberration without requiring computational correction. We demonstrate its efficiency for astigmatic imaging in a 1.2 μm range above the coverslip...
January 15, 2018: Optics Letters
https://www.readbyqxmd.com/read/29328088/determination-of-the-optimum-double-pass-image-through-focus-operators
#5
Anibal G de Paul, Roberto F Sanchez, Luis A Issolio
A set of autofocus operators (AFO) are assessed for their ability to determine the optimal double-pass image as well as their potential to detect the focus lines and the disc of least confusion in astigmatic eyes. Eight AFO and three optical quality parameters (OQP) often used to analyze double-pass aerial images were considered. To quantify the discriminative power of each AFO and OQP, a maximum discrimination (MD) parameter was proposed. Double-pass images were obtained from an artificial eye with an induced astigmatism (Cylinder: -1  D, -0...
January 1, 2018: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/29327252/compared-vulnerabilities-to-small-cardiac-motions-between-different-cameras-used-for-myocardial-perfusion-imaging
#6
Julien Salvadori, Yolande Petegnief, Remi Sabbah, Olivier Morel, Hatem Boulahdour, Gilles Karcher, Pierre-Yves Marie, Laetitia Imbert
This phantom-based study was aimed to determine whether cardiac CZT-cameras, which provide an enhanced spatial resolution and image contrast compared to Anger cameras, are similarly affected by small cardiac motions. Translations of a left ventricular (LV) insert at half-SPECT acquisitions through six possible orthogonal directions and with 5- or 10-mm amplitude were simulated on the Discovery NM-530c and DSPECT CZT-cameras and on an Anger Symbia T2 camera equipped with an astigmatic (IQ.SPECT) or conventional parallel-hole collimator (Conv...
January 11, 2018: Journal of Nuclear Cardiology: Official Publication of the American Society of Nuclear Cardiology
https://www.readbyqxmd.com/read/29323426/vision-in-children-with-autism-spectrum-disorder-a-critical-review
#7
REVIEW
Julie-Anne Little
Autism spectrum disorder (ASD) is a common neurodevelopmental condition with approximately 1-2 per cent prevalence in the population. The condition has lifelong effects for the individual and family, and early intervention and management helps maximise quality of life and outcomes. Many studies of vision in ASD have attempted to link the behavioural and sensory deficits in ASD with underlying visual processing. From this work, it is clear that individuals with ASD 'see' and process the world differently, but there remain gaps in our understanding...
January 11, 2018: Clinical & Experimental Optometry: Journal of the Australian Optometrical Association
https://www.readbyqxmd.com/read/29321616/defocus-and-magnification-dependent-variation-of-tem-image-astigmatism
#8
Rui Yan, Kunpeng Li, Wen Jiang
Daily alignment of the microscope is a prerequisite to reaching optimal lens conditions for high resolution imaging in cryo-EM. In this study, we have investigated how image astigmatism varies with the imaging conditions (e.g. defocus, magnification). We have found that the large change of defocus/magnification between visual correction of astigmatism and subsequent data collection tasks, or during data collection, will inevitably result in undesirable astigmatism in the final images. The dependence of astigmatism on the imaging conditions varies significantly from time to time, so that it cannot be reliably compensated by pre-calibration of the microscope...
January 10, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29319597/repeated-same-day-versus-single-tomography-measurements-of-keratoconic-eyes-for-analysis-of-disease-progression
#9
Wolf Wonneberger, Bertil Sterner, Ulrika MacLean, Margareta Claesson, Madeleine Zetterberg
PURPOSE: Corneal tomography is used to assess progression of keratoconus and to direct clinical decisions regarding corneal cross-linking. The purpose of this study was to analyze the variability of repeated Scheimpflug-tomography (Pentacam Classic; Oculus, Wetzlar, Germany) measurements of keratoconic eyes in a clinical setting and to assess the validity of such measurements as a clinical decision-making tool. METHODS: Eighty keratoconic eyes of 45 patients (age range 16-32 years) were examined at baseline and after follow-up periods of 3 to 6 months using 3 consecutive tomography measurements at each visit...
January 9, 2018: Cornea
https://www.readbyqxmd.com/read/29315444/unusual-internal-astigmatism-due-to-severe-capsule-contraction-syndrome
#10
Pierre Zéboulon, Damien Gatinel
PURPOSE: To describe a case of severe capsule contraction syndrome causing significant astigmatism due to intraocular lens (IOL) folding. METHODS: Case report. RESULTS: Capsule fibrosis and contraction resulted in bending of the hydrophilic IOL along its long axis. Anterior Nd:YAG capsulotomy resolved the situation and restored the patient's visual acuity. CONCLUSIONS: Hydrophilic IOLs are more susceptible to capsule contraction due to the increased flexibility of highly hydrated materials...
January 1, 2018: Journal of Refractive Surgery
https://www.readbyqxmd.com/read/29315436/energy-setting-and-visual-outcomes-in-smile-a-retrospective-cohort-study
#11
Liuyang Li, Julie M Schallhorn, Jiaonan Ma, Tong Cui, Yan Wang
PURPOSE: To assess the independent effect of energy setting on postoperative uncorrected distance visual acuity (UDVA) in small incision lenticule extraction (SMILE) and further investigate an optimal energy setting for the 4.5-μm spot-track-distance, which is in wide clinical use. METHODS: A total of 1,130 eyes were included in a retrospective cohort study from Tianjin Eye Hospital, Tianjin Medical University from April 2015 to July 2016. Energy settings and baseline characteristics were recorded and 3-month UDVA was tested by a nurse blinded to the energy settings used...
January 1, 2018: Journal of Refractive Surgery
https://www.readbyqxmd.com/read/29315401/development-of-a-real-time-wave-field-reconstruction-tem-system-ii-correction-of-coma-aberration-and-3-fold-astigmatism-and-real-time-correction-of-2-fold-astigmatism
#12
Takahiro Tamura, Yoshihide Kimura, Yoshizo Takai
In this study, a function for the correction of coma aberration, 3-fold astigmatism and real-time correction of 2-fold astigmatism was newly incorporated into a recently developed real-time wave field reconstruction TEM system. The aberration correction function was developed by modifying the image-processing software previously designed for auto focus tracking, as described in the first article of this series. Using the newly developed system, the coma aberration and 3-fold astigmatism were corrected using the aberration coefficients obtained experimentally before the processing was carried out...
January 5, 2018: Microscopy
https://www.readbyqxmd.com/read/29308773/evaluation-of-visual-outcomes-after-toric-intraocular-lens-implantation
#13
H R Ng, C H Goh, Y S Ngim, J Juliana
PURPOSE: To evaluate postoperative visual acuity, refractive status and rotational stability of toric intraocular lens (IOL) in correcting pre-existing corneal astigmatism. METHODS: A total of 69 patients with topographic corneal astigmatism of 1.0 Diopter (D) and above who underwent cataract surgery between June 2015 and December 2016 were included in this retrospective observational study. All preoperative toric IOL calculations were performed using immersion biometry...
December 2017: Medical Journal of Malaysia
https://www.readbyqxmd.com/read/29296551/surgical-outcome-of-deep-anterior-lamellar-keratoplasty-with-air-assisted-manual-dissection-for-corneas-with-previous-inflammation-or-fibrosis
#14
Yi-Ju Ho, Cheng-Hsiu Wu, Hung-Chi Chen, Chin-Shi Hsiao, Yi-Jen Hsueh, David Hui-Kang Ma
PURPOSE: To report our experience in air-assisted manual dissection deep anterior lamellar keratoplasty (DALK) for the treatment of corneal scar with previous inflammation and fibrosis. MATERIALS AND METHODS: We retrospectively reviewed the medical history of 21 patients (male:female = 13:8 mean age 41.9 years old) with corneal pathology from previous infection and inflammation. Trephination diameter ranged from 7.0 to 8.0 mm, and the graft was oversized by 0.25-0...
October 2017: Taiwan Journal of Ophthalmology
https://www.readbyqxmd.com/read/29296550/comparison-of-transepithelial-corneal-crosslinking-with-epithelium-off-crosslinking-epithelium-off-cxl-in-adult-pakistani-population-with-progressive-keratoconus
#15
Bushra Akbar, Rana Intisar-Ul-Haq, Mazhar Ishaq, Ayesha Fawad, Sabahat Arzoo, Kashif Siddique
PURPOSE: The purpose of this study is to compare the safety and efficacy of transepithelial corneal crosslinking (CXL) with epithelium-off crosslinking (epithelium-off CXL) in the treatment of progressive keratoconus in adult Pakistani population. MATERIALS AND METHODS: Sixty-four eyes of 64 consecutive patients of progressive keratoconus were included in this quasi-experimental study. Thirty-two eyes received transepithelial CXL with Peschke TE (0.25% riboflavin (Vitamin B2), 1...
October 2017: Taiwan Journal of Ophthalmology
https://www.readbyqxmd.com/read/29289167/optimal-design-of-a-%C3%AE-760-mm-lightweight-sic-mirror-and-the-flexural-mount-for-a-space-telescope
#16
Zongxuan Li, Xue Chen, Shaoju Wang, Guang Jin
A flexural support technique for lightweighted Primary Mirror Assembly (PMA) of a space telescope is presented in this article. The proposed three-point flexural mount based on a cartwheel flexure can maintain the surface figure of the PMA in a horizontal optical testing layout. The on-orbit surface error of the PMA causes significant degradation in image quality. On-ground optical testing cannot determine the zero-gravity figure of the PMA due to surface distortion by gravity. We unveiled the crucial fact that through a delicate mounting structure design, the surface figure can remain constant precisely without inducing distinguishable astigmatism when PMA rotates with respect to the optical axis, and the figure can be considered as the zero-gravity surface figure on the orbit...
December 2017: Review of Scientific Instruments
https://www.readbyqxmd.com/read/29288835/evaluation-of-anterior-segment-parameters-in-patients-with-turner-syndrome-using-scheimpflug-imaging
#17
Merve Inanc, Kemal Tekin, Erdal Kurnaz, Mehmet Citirik, Gülsah Altas, Zehra Aycan
PURPOSE: To compare the anterior segment parameters in patients with Turner syndrome (TS) as measured by the Pentacam HR-Scheimpflug imaging system with those of healthy control subjects. METHODS: This cross-sectional prospective study included 35 patients with TS and 30 age-matched controls. Corneal topographic analysis was performed using the Pentacam HR-Scheimpflug imaging system (Oculus, Wetzlar, Germany). The power of the corneal astigmatism, mean keratometry (Km) values for the both front and back surfaces of the cornea, maximum keratometry (Kmax), central corneal thickness (CCT), corneal volume (CoV), white-to-white diameter (WTW), chamber volume (CaV), angle and anterior chamber depth (ACD) values were recorded...
December 27, 2017: Journal of AAPOS: the Official Publication of the American Association for Pediatric Ophthalmology and Strabismus
https://www.readbyqxmd.com/read/29284444/comparison-of-efficacy-between-coaxial-microincision-and-standard-incision-phacoemulsification-in-patients-with-age-related-cataracts-a-meta-analysis
#18
Lijun Wang, Xiao Xiao, Lin Zhao, Yi Zhang, Jianming Wang, Aiyi Zhou, Jianchao Wang, Qian Wu
BACKGROUND: Incision size plays a critical role in the efficacy of cataract surgery, but the available evidence on ideal incision size is inconsistent. In this study, we conducted a meta-analysis to evaluate the efficacy of coaxial microincisional phacoemulsification surgery (MICS) compared with that of standard-incision phacoemulsification surgery (SICS) in patients with age-related cataracts. METHODS: The Cochrane Library (Wiley Online Library), PubMed, Medline, National Knowledge Infrastructure (CNKI), and VIP databases were searched to identify reports of clinical randomized controlled trials (RCTs) comparing MICS to SICS for the treatment of age-related cataracts...
December 29, 2017: BMC Ophthalmology
https://www.readbyqxmd.com/read/29283949/changes-in-corneal-curvature-after-epiblepharon-surgery-in-children
#19
Dong Hyun Lee, Jae Ho Jung, Jung Hyo Ahn
PURPOSE: We aimed to determine the change in corneal topography for 2-different corneal zones and 4-quadrants after epiblepharon correction in children. METHODS: We retrospectively reviewed 39 patients (74 eyes) who underwent epiblepharon surgery. Keratometry measurements of corneal curvature were performed for 2 optical zones defined as circular areas with a radius of 3 and 5 mm from the corneal apex. Each optical zone was divided into quadrants (nasal, superior, temporal, and inferior)...
December 27, 2017: Journal of Craniofacial Surgery
https://www.readbyqxmd.com/read/29283679/influence-of-short-term-orthokeratology-to-corneal-tangent-modulus-a-randomized-study
#20
Andrew Kc Lam, Stanley Yy Leung, Ying Hon, Lu Shu-Ho, Kit-Ying Wong, Pui-Kwan Tiu, David Cc Lam
PURPOSE: Influence of orthokeratology on corneal biomechanics is equivocal using Ocular Response Analyzer, ORA. Implementing indentation method, corneal tangent modulus was measured and monitored in short-term orthokeratology. MATERIALS AND METHODS: Sixteen young subjects with refractive errors between -4D to -5D sphere and astigmatism within -1.50D were recruited. One randomly selected eye wore orthokeratology lens (treatment), and the fellow eye wore conventional rigid gas permeable lens (control)...
December 28, 2017: Current Eye Research
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