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https://www.readbyqxmd.com/read/29791391/effects-of-aberrations-on-effective-point-spread-function-in-sted-microscopy
#1
Yanghui Li, Hui Zhou, Xiaoyu Liu, Yuxue Li, Le Wang
Like other imaging techniques, stimulated emission depletion (STED) microscopy suffers from aberrations. While their effects on depletion patterns have been explicitly investigated, the study on how aberrations affect the effective point spread function (PSF) in STED microscopy is still missing. For STED researchers, however, this study is beneficial, as it directly bridges image qualities and aberrations. In this paper, we quantitatively analyze the effects of primary aberrations, including astigmatism, coma, trefoil, and spherical aberration, in two-dimensional (2D) and three-dimensional (3D) STED microscopy, and further discuss the corresponding aberration tolerance...
May 20, 2018: Applied Optics
https://www.readbyqxmd.com/read/29791378/design-of-an-adjustable-bipod-flexure-for-a-large-aperture-mirror-of-a-space-camera
#2
Bei Liu, Wei Wang, Yan-Jun Qu, Xu-Peng Li, Xiao Wang, Hui Zhao
An adjustable bipod flexure (ABF) technique for a large-aperture mirror of a space camera is presented. The proposed flexure mount can decrease the surface distortions caused by the machining error and the assembly error of the mirror assembly (MA) in a horizontal optical testing layout. Through the analysis of the compliance matrix of conventional bipod flexure, the positional relationship between the rotation center and the apex of the flexure is investigated. Then, the principle of the adjustable flexure, known as the trapezoidal switching principle, is proposed based on the analysis result...
May 20, 2018: Applied Optics
https://www.readbyqxmd.com/read/29787490/clinical-performance-of-a-new-bitangential-mini-scleral-lens
#3
Henny M Otten, Bart J J J van der Linden, Esther-Simone Visser
SIGNIFICANCE: New bitangential mini-scleral lens designs provide a highly precise fit, follow the scleral shape, are comfortable to wear, and can correct residual astigmatism. This new scleral lens design complements the arsenal of medical contact lenses available to eye care practitioners. PURPOSE: The aim of this study was to evaluate the subjective and objective performance of a new mini-scleral lens design with a bitangential periphery. METHODS: In this observational study, data were collected for up to 15 months (median, 84 days; interquartile range, 76 days) from the left eyes of 133 patients fitted with this newly designed lens...
May 21, 2018: Optometry and Vision Science: Official Publication of the American Academy of Optometry
https://www.readbyqxmd.com/read/29785083/treatment-of-high-myopia-myopic-astigmatism-with-a-combination-of-wavelight-contoura-with-lyra-protocol-and-wavefront-optimized-treatment
#4
Manoj Motwani
Purpose: The aim of this article was to demonstrate how WaveLight Contoura and wavefront optimization (WFO) can be used together to treat high myopia/myopic astigmatism corrections. Materials and methods: A retrospective analysis was conducted on 24 consecutive myopic/myopic astigmatism eyes that exceeded the Contoura labeling of -8.00 with -3.00 D of astigmatism. Residual correction after Contoura with Layer Yolked Reduction of Astigmatism protocol was treated with WFO Contoura LASIK correction...
2018: Clinical Ophthalmology
https://www.readbyqxmd.com/read/29784159/changes-in-corneal-biomechanical-properties-after-24-hours-of-continuous-intraocular-pressure-monitoring-using-a-contact-lens-sensor
#5
Laura Morales-Fernandez, Javier Garcia-Bella, Jose M Martinez-de-la-Casa, Rubén Sanchez-Jean, Federico Saenz-Frances, Pedro Arriola-Villalobos, Lucia Perucho, Enrique Santos-Bueso, Julian Garcia-Feijoo
OBJECTIVE: This study was designed to assess changes in corneal topography and biomechanics after intraocular pressure (IOP) monitoring using the Triggerfish contact lens sensor (CLS). METHODS: For this prospective study, 30 eyes of 30 subjects: 14 healthy subjects (G1) and 6 glaucoma patients (G2), were recruited for 24 hours of continuous IOP monitoring using the CLS. The following measurements were taken before CLS fitting and after lens removal: maximum keratometry (Kmax), mean keratometry (MK), and corneal astigmatism (Cyl) measured through Pentacam corneal topography, and the corneal biomechanical variables corneal hysteresis (CH) and corneal resistance factor (CRF) measured with the Ocular Response Analyzer (ORA)...
June 2018: Canadian Journal of Ophthalmology. Journal Canadien D'ophtalmologie
https://www.readbyqxmd.com/read/29783210/the-effectiveness-of-sphero-cylindrical-correction-at-a-short-distance-in-presbyopic-age-patients-with-the-first-detected-astigmatism
#6
Iryna M Bezkorovayna, Victoria V Ryadnova, Denys O Nakonechnyi, Anna O Bezkorovayna
OBJECTIVE: Introduction: The practical results of optical correction without considering the cylindrical component at close dictance do not always satisfy the patient in everyday visual activity. The aim: Compare the effect of sphero-cylindrical and spherical correction in presbyopic patients with the first detected astigmatism at a close distance work. PATIENTS AND METHODS: Materials and methods: The article presents the results of a survey of 43 patients (86 eyes) aged 38 to 59 years, on average 47 ± 0...
2018: Wiadomości Lekarskie: Organ Polskiego Towarzystwa Lekarskiego
https://www.readbyqxmd.com/read/29780931/case-of-progressive-hyperopia-due-to-flattening-of-cornea
#7
Hiromasa Hirai, Shinji Maruoka, Tadanobu Yoshikawa, Nahoko Ogata
Purpose: To report a case that had a progressive decrease in the visual acuity caused by a progressive increase in the hyperopia due to a flattening of the cornea. Observations: A 50-year-old woman complained of decreased vision in both eyes. Her decimal best-corrected visual acuity was 1.2 in the right and 0.5 in the left eyes, and the refractive error (spherical equivalent) was +3.75 diopters (D) for the right eye and +6.5 D for the left eye. Slit-lamp examinations showed clear corneas but Descemet's folds and fine pigmentations and opacities were present beneath the corneal epithelium in both eyes...
June 2018: American Journal of Ophthalmology Case Reports
https://www.readbyqxmd.com/read/29780908/rare-corneal-complication-following-selective-laser-trabeculoplasty
#8
Sarah Dougherty Wood, Angela Elam, Sayoko Moroi
Purpose: This case report describes two glaucoma patients who underwent selective laser trabeculoplasty (SLT) and developed a rare post-procedure corneal complication and subsequent permanent corneal distortions and reduced acuity. Observations: Both patients experienced early post-procedure corneal edema, reduced visual acuity, and pain. Each patient was treated with topical steroids with resolution of the edema, but each patient had irregular corneal astigmatism which was not present pre-operatively and did not resolve...
June 2018: American Journal of Ophthalmology Case Reports
https://www.readbyqxmd.com/read/29778108/rotation-of-a-toric-intraocular-lens-from-neodymium-yag-laser-posterior-capsulotomy
#9
Clemens Kaindlstorfer, Mario Kneifl, Peter Reinelt, Ulrich Schönherr
A 77-year-old man had cataract surgery in the left eye in March 2017. A toric intraocular lens (IOL) was implanted because of astigmatism. The postoperative meridian of the IOL was located nearly exactly in the planned meridian, which was controlled 1 week later with ray-tracing aberrometry (iTrace) and the smartphone application Axis Assistant. The referring ophthalmologist proceeded directly with a neodymium:YAG (Nd:YAG) laser posterior capsulotomy in his own office, after which the meridian of the implanted toric IOL was rotated more than 115 degrees...
April 2018: Journal of Cataract and Refractive Surgery
https://www.readbyqxmd.com/read/29777048/corneal-shape-changes-of-the-total-and-posterior-cornea-after-temporal-versus-nasal-clear-corneal-incision-cataract-surgery
#10
Ken Hayashi, Tatsuhiko Sato, Motoaki Yoshida, Koichi Yoshimura
AIM: To compare changes in the shape and astigmatism of the total and posterior cornea between eyes with a nasal clear corneal incision (CCI) and eyes with a temporal CCI in cataract surgery. METHODS: The left eyes of 100 patients undergoing phacoemulsification were randomly assigned to undergo a 2.4 mm nasal (nasal CCI group) or temporal CCI (temporal CCI group). Corneal astigmatic changes were compared between groups using power vector analysis, and corneal shape changes were compared using videokeratography maps at 2 days, and at 2, 4 and 8 weeks postoperatively...
May 18, 2018: British Journal of Ophthalmology
https://www.readbyqxmd.com/read/29776767/-visual-outcomes-5-years-after-small-incision-lenticule-extraction-smile-surgery-on-spherocylindrical-myopia-eyes-from-616-eyes
#11
J Burazovitch, H Ferguene, D Naguszewski
OBJECTIVE: Determine if the visual criteria of the technique of surgery refractive by Femtosecond Laser-assisted duckweed Extraction - Small Lenticule Extraction (FLEx-Smile® ), realized in the laser femtosecond VisuMax® (Carl Zeiss Meditec, Jena, Germany), are stable, secure, effective and predictable in the long term, to the nearsighted and astigmatic. MODEL OF THE STUDY: Retrospective study, monocentric with data collected between March 2012 and March 2017...
May 15, 2018: Journal Français D'ophtalmologie
https://www.readbyqxmd.com/read/29774172/moebius-syndrome-with-hypoglossal-palsy-syndactyly-brachydactyly-and-anisometropic-amblyopia
#12
Muhammad Hassaan Ali, Samreen Jamal, Muhammad Ather Rashid, Usman Javaid, Nadeem Hafeez Butt
Moebius syndrome is a rare cause of congenital facial and abducens palsy.  It is sometimes associated with musculoskeletal abnormalities and other cranial nerve palsies. Genetics and ischemic insults to the fetus are considered to be the cause of this syndrome. We report here a 12-year-old female patient who was presented to us with poor cosmesis of her face, with associated decreased vision and lagophthalmos in her left eye. She didn't have any signs of exposure keratopathy in the affected eye. Her best-corrected vision was 20/20 and 20/60 in right and left eyes respectively...
March 16, 2018: Curēus
https://www.readbyqxmd.com/read/29772222/outcomes-of-laser-in-situ-keratomileusis-and-photorefractive-keratectomy-in-patients-taking-isotretinoin
#13
Julio Ortega-Usobiaga, Fernando Llovet-Osuna, Mohammad Reza Djodeyre, Rafael Bilbao-Calabuig, Félix González-López, Andrea Llovet-Rausell, Vasyl Druchkiv
PURPOSE: To determine the functional outcomes of laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) in patients taking isotretinoin, which is contraindicated for these procedures. DESIGN: Multicentre, retrospective, interventional case series METHODS: All patients taking isotretinoin who underwent LASIK or PRK from January 2003 to September 2017 were included (group 1). Patients were compared with those undergoing LASIK or PRK who had taken isotretinoin previously but not in the previous 6 months (group 2)...
May 14, 2018: American Journal of Ophthalmology
https://www.readbyqxmd.com/read/29770640/comparison-of-anterior-posterior-and-total-corneal-astigmatism-measured-using-a-single-scheimpflug-camera-in-healthy-and-keratoconus-eyes
#14
Young Choi, Youngsub Eom, Jong Suk Song, Hyo Myung Kim
PURPOSE: To compare the effect of posterior corneal astigmatism on the estimation of total corneal astigmatism using anterior corneal measurements (simulated keratometry [K]) between eyes with keratoconus and healthy eyes. METHODS: Thirty-three eyes of 33 patients with keratoconus of grade I or II and 33 eyes of 33 age- and sex-matched healthy control subjects were enrolled. Anterior, posterior, and total corneal cylinder powers and flat meridians measured by a single Scheimpflug camera were analyzed...
May 15, 2018: Korean Journal of Ophthalmology: KJO
https://www.readbyqxmd.com/read/29766557/risk-factors-for-ocular-complications-in-periocular-infantile-hemangiomas
#15
Liat Samuelov, Michael Kinori, Karen Rychlik, Meghana Konanur, Sarah L Chamlin, Bahram Rahmani, Anthony J Mancini
BACKGROUND/OBJECTIVES: Infantile hemangiomas are the most common benign tumors of childhood. Although some children with periocular infantile hemangiomas do not require treatment, these lesions may result in amblyopia and visual impairment if not properly treated. We have attempted to characterize clinical features of periocular infantile hemangiomas that predict negative ocular outcomes and thus require prompt referral to an ophthalmologist and initiation of therapy. METHODS: This study included children with periocular infantile hemangiomas consecutively seen at Ann & Robert H...
May 15, 2018: Pediatric Dermatology
https://www.readbyqxmd.com/read/29765106/the-mitochondrial-genome-of-the-oribatid-mite-paraleius-leontonychus-new-insights-into-trna-evolution-and-phylogenetic-relationships-in-acariform-mites
#16
Sylvia Schäffer, Stephan Koblmüller, Ingeborg Klymiuk, Gerhard G Thallinger
Bilaterian mitochondrial (mt) genomes are circular molecules that typically contain 37 genes. To date, only a single complete mitogenome sequence is available for the species-rich sarcoptiform mite order Oribatida. We sequenced the mitogenome of Paraleius leontonychus, another species of this suborder. It is 14,186 bp long and contains 35 genes, including only 20 tRNAs, lacking tRNA Gly and tRNA Tyr . Re-annotation of the mitogenome of Steganacarus magnus increased the number of mt tRNAs for this species to 12...
May 15, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29757851/effect-of-posterior-corneal-vesicles-on-corneal-endothelial-cell-density-and-anisometropic-amblyopia
#17
Atsushi Noguchi, Naoki Okumura, Chie Sotozono, Shigeru Kinoshita
PURPOSE: To evaluate the effect of corneal vesicles in patients with posterior corneal vesicles (PCV) on corneal endothelial cell (CEC) density and the acquisition of amblyopia. METHODS: In this retrospective study of patients with PCV (18 eyes of 14 patients), CEC density was examined by noncontact specular microscopy during each follow-up examination. Best-corrected visual acuity and the objective refractive error were also examined. RESULTS: Of the 14 total patients, 10 were diagnosed with PCV and 4 were diagnosed with bilateral suspected PCV or posterior polymorphous corneal dystrophy (PPCD), and in all patients, no ocular abnormality other than corneal vesicles was observed...
May 1, 2018: Cornea
https://www.readbyqxmd.com/read/29757850/corneal-irregular-astigmatism-and-curvature-changes-after-small-incision-lenticule-extraction-three-year-follow-up
#18
Haris Sideroudi, Apostolos Lazaridis, Anke Messerschmidt-Roth, Georgios Labiris, Vassilios Kozobolis, Walter Sekundo
PURPOSE: To evaluate the long-term changes in anterior and posterior corneal irregular astigmatism and curvatures after small incision lenticule extraction (SMILE). METHODS: Fifty eyes of 28 patients underwent SMILE for myopic astigmatism. All procedures were performed using the VisuMax® femtosecond laser. A Scheimpflug camera was used for preoperative and 3-year postoperative tomography. Anterior and posterior corneal Fourier parameters (spherical component, regular astigmatism, asymmetry, and irregularity) and curvature data were evaluated and compared within 2 subgroups according to the magnitude of the refractive correction (low myopia group: spherical equivalent (SEQ) ≥ -6 D; high myopia group: (SEQ) < -6 D)...
April 27, 2018: Cornea
https://www.readbyqxmd.com/read/29750010/comparative-analysis-of-safety-and-efficacy-of-photorefractive-keratectomy-versus-photorefractive-keratectomy-combined-with-crosslinking
#19
Gitansha Shreyas Sachdev, Shreyas Ramamurthy, Ramamurthy Dandapani
Purpose: To assess the safety, efficacy, and refractive predictability of half-fluence accelerated corneal collagen crosslinking (CXL) applied concurrently with photorefractive keratectomy (PRK), and compare the results to standard PRK. Setting: Refractive Services, The Eye Foundation, Coimbatore, India. Design: Interventional comparative case series. Methods: Patients seeking refractive correction for myopia or myopic astigmatism were included in the study...
2018: Clinical Ophthalmology
https://www.readbyqxmd.com/read/29747366/-a-multicenter-study-of-the-effectiveness-and-safety-of-toric-intraocular-lens-implantation
#20
X D Song, Y S Hao, Y Z Bao, Z H Li, H Zhang, A Y Yu, M S Zhao, Y S Huang, J Fang, Y Liu, N L Wang
Objective: To evaluate the effectiveness and safety of Proming(®)Toric intraocular lens (IOL) in adults with cataract combined with corneal regular astigmatism. Methods: Multicentre, randomized, open and positive parallel controlled clinical study. A total of 121 patients (121 eyes) who had cataract combined with corneal regular astigmatism and met the inclusion criteria were enrolled in 9 hospitals from May 2014 to May 2016. There were 45 males and 76 females and the median age was 71 (42-88) years old. A total of 121 patients (121 eyes) were randomly assigned to the study group and the control group through the Central Randomization System...
May 11, 2018: [Zhonghua Yan Ke za Zhi] Chinese Journal of Ophthalmology
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