Corneal Astigmatism Measurements Comparison among Ray-Tracing Aberrometry, Partial Coherence Interferometry, and Scheimpflug Imaging System.

Purpose: To investigate interdevice agreement among corneal topography/ray-tracing aberrometry (iTrace), partial coherence interferometry (IOLMaster), and Scheimpflug imaging (Pentacam) for the measurement of corneal astigmatism.

Methods: The analysis included 90 eyes of 90 subjects without ocular disease. The main outcome measures were corneal cylinder power and axis of astigmatism.

Comparison of Corneal Power and Corneal Astigmatism of Different Diameter Zones Centered on the Pupil and Corneal Apex Using Scheimpflug Tomography.

Purpose: Using Scheimpflug tomography to investigate the difference in corneal power and corneal astigmatism between 3- and 4-mm diameter zones centered on the pupil and corneal apex.

Methods: A total of 90 eyes were included in this study. Axial keratometry, total refractive power, and true net power centered on the pupil and corneal apex in 3- and 4-mm diameter zones were assessed.

Effect of pupil dilation on biometric measurements and intraocular lens power calculations in schoolchildren.

Purpose: To investigate the effect of pupil dilation on ocular biometric parameters and intraocular lens (IOL) power calculation in schoolchildren using the Lenstar LS 900.

Methods: One hundred forty eyes of 140 healthy schoolchildren were included in the analysis. Axial length (AL), central corneal thickness (CCT), aqueous depth (AD), anterior chamber depth (ACD), lens thickness (LT), flat keratometry (K), steep K, astigmatism, white-to-white (WTW), and iris/pupil barycenter distance were measured, before and after pupil dilation.

Light scattering measurements in electron-beam sterilized corneas stored in recombinant human serum albumin.

Irradiated corneal tissues have been used for a variety of ophthalmic procedures including glaucoma drainage device covers and lamellar grafts. The maintenance of corneal clarity is important, as light obstructions resulting from processing or long-term storage of irradiated corneas may negatively affect vision and postoperative cosmesis. It has been reported that corneal tissues can be preserved in human serum albumin (HSA), however, the clarity of corneas after long-term storage in HSA has not been well described.

Guiding flying-spot laser transepithelial phototherapeutic keratectomy with optical coherence tomography.

Purpose: To analyze transepithelial phototherapeutic keratectomy (PTK) results using optical coherence tomography (OCT) and develop a model to guide the laser dioptric and depth settings.

Setting: Casey Eye Institute, Portland, Oregon, USA.

Design: Prospective nonrandomized case series.

Distinguishing between contact lens warpage and ectasia: Usefulness of optical coherence tomography epithelial thickness mapping.

Purpose: To distinguish between corneal ectasia and contact lens-related warpage by characteristic patterns on corneal topography and optical coherence tomography (OCT) epithelial thickness maps.

Setting: Casey Eye Institute, Portland, Oregon, USA.

Design: Prospective and retrospective case series.

Differentiating Keratoconus and Corneal Warpage by Analyzing Focal Change Patterns in Corneal Topography, Pachymetry, and Epithelial Thickness Maps.

Purpose: To differentiate between keratoconus and contact lens-related corneal warpage by combining focal change patterns in anterior corneal topography, pachymetry, and epithelial thickness maps.

Methods: Pachymetry and epithelial thickness maps of normal, keratoconus, and warpage, and forme fruste keratoconus (FFK) eyes were obtained from a Fourier-domain optical coherence tomography (OCT). Epithelial pattern standard deviation (PSD) was calculated and combined with two novel indices, the Warpage Index and the Anterior Ectasia Index, to differentiate between normal, keratoconus, and warpage eyes.

Deep Laser-Assisted Lamellar Anterior Keratoplasty With Microkeratome-Cut Grafts.

Purpose: The goals of this laboratory study were to evaluate the interface quality in laser-assisted lamellar anterior keratoplasty (LALAK) with microkeratome-cut grafts and achieve good graft-host apposition.

Methods: Simulated LALAK surgeries were performed on 6 pairs of eye-bank corneoscleral discs. Anterior lamellar grafts were precut with microkeratomes.

Origins of polarization-dependent anisotropic X-ray scattering from organic thin films.

Organic thin films that have no overall in-plane directional ordering often nonetheless produce anisotropic scattering patterns that rotate with the polarization of incident resonant X-rays. Isotropic symmetry is broken by local correlations between molecular orientation and domain structure. Such examples of molecular alignment at domain interfaces and within the bulk of domains, which are both critical to fields such as organic electronics, are simulated and compared with experimental scattering.

Imaging the anterior eye with dynamic-focus swept-source optical coherence tomography.

A custom-built dynamic-focus swept-source optical coherence tomography (SS-OCT) system with a central wavelength of 1310 nm was used to image the anterior eye from the cornea to the lens. An electrically tunable lens was utilized to dynamically control the positions of focusing planes over the imaging range of 10 mm. The B-scan images were acquired consecutively at the same position but with different focus settings.

Comparison of Anterior Segment Biometric Measurements between Pentacam HR and IOLMaster in Normal and High Myopic Eyes.

Purpose: To compare the anterior chamber depth (ACD), keratometry (K) and astigmatism measurements taken by IOLMaster and Pentacam HR in normal and high myopic (HM) eyes.

Design: A prospective observational case series.

Methods: Sixty-six normal eyes and 59 HM eyes underwent ACD, keratometry and astigmatism measurements with both devices.

Comparison of Newer Intraocular Lens Power Calculation Methods for Eyes after Corneal Refractive Surgery.

Purpose: To compare the newer formulae, the optical coherence tomography (OCT)-based intraocular lens (IOL) power formula (OCT formula) and the Barrett True-K formula (True-K), with the methods on the American Society of Cataract and Refractive Surgery (ASCRS) calculator in eyes with previous myopic LASIK/photorefractive keratectomy (PRK).

Design: Prospective case series.

Participants: A total of 104 eyes of 80 patients who had previous myopic LASIK/PRK and subsequent cataract surgery and IOL implantation.

Laboratory Evaluation of Femtosecond Laser Lamellar Cuts in Gamma-Irradiated Corneas.

Purpose: To evaluate the stromal interface quality after femtosecond laser full lamellar cuts in gamma-irradiated corneas (VisionGraft sterile cornea) and to determine the limits of the cut depth using the VisionGraft as donor corneas for laser-assisted lamellar anterior keratoplasty.

Methods: Fourteen VisionGraft corneas underwent full lamellar cuts using the femtosecond laser. The percent cut depth was 17% to 21% (100 μm, n = 2), 31% to 35% (n = 3), 38% to 40% (n = 3), 45% to 48% (n = 3), and 50% (n = 3) of the total stromal thickness (not including the epithelium).

Corneal Epithelial Remodeling after LASIK Measured by Fourier-Domain Optical Coherence Tomography.

Purpose. To quantify corneal epithelial thickness changes after myopic LASIK by OCT. Methods.

Interface quality of different corneal lamellar-cut depths for femtosecond laser-assisted lamellar anterior keratoplasty.

Purpose: To evaluate the interface quality of different corneal lamellar-cut depths with the femtosecond laser and determine a feasible range of depth for femtosecond laser-assisted lamellar anterior keratoplasty.

Setting: Casey Eye Institute, Portland, Oregon, USA.

Design: Experimental study.

Predicting transepithelial phototherapeutic keratectomy outcomes using Fourier domain optical coherence tomography.

Purpose: The aim of this study was to use Fourier domain optical coherence tomography to predict transepithelial phototherapeutic keratectomy outcomes.

Methods: This is a prospective case series. Subjects with anterior stromal corneal opacities underwent an excimer laser phototherapeutic keratectomy (PTK) combined with a photorefractive keratectomy using the VISX S4 excimer laser (AMO, Inc, Santa Ana, CA).

Keratoconus diagnosis with optical coherence tomography–based pachymetric scoring system.

Purpose: To develop an optical coherence tomography (OCT) pachymetry map–based keratoconus risk scoring system.

Settings: Doheny Eye Institute, University of Southern California, Los Angeles, California, and Brass Eye Center, New York, New York, USA; Department of Ophthalmology, Affiliated Eye Hospital of Wenzhou Medical College, Wenzhou, China.

Design: Cross-sectional study.

Optical coherence tomography-based corneal power measurement and intraocular lens power calculation following laser vision correction (an American Ophthalmological Society thesis).

Purpose: To use optical coherence tomography (OCT) to measure corneal power and improve the selection of intraocular lens (IOL) power in cataract surgeries after laser vision correction.

Methods: Patients with previous myopic laser vision corrections were enrolled in this prospective study from two eye centers. Corneal thickness and power were measured by Fourier-domain OCT.

Use of fourier-domain optical coherence tomography to evaluate anterior stromal opacities in donor corneas.

Purpose. To evaluate Fourier-domain optical coherence tomography (FD-OCT) as an adjunct to traditional slit lamp examination of donor corneas with suspected Anterior Stromal Opacities. Methods.

Evaluating DSAEK graft deturgescence in preservation medium after microkeratome cut with optical coherence tomography.

Purpose: To evaluate the Descemet stripping automated endothelial keratoplasty (DSAEK) graft deturgescence in preservation medium after microkeratome cut using Fourier domain optical coherence tomography.

Methods: The central and peripheral thickness of DSAEK grafts was measured by Fourier domain optical coherence tomography immediately after microkeratome cuts and 1, 2, 3, and 4 hours afterward. All measurements were taken when the grafts were stored in 4°C preservation medium.

Pilot Study for OCT Guided Design and Fit of a Prosthetic Device for Treatment of Corneal Disease.

Purpose. To assess optical coherence tomography (OCT) for guiding design and fit of a prosthetic device for corneal disease. Methods.

Beveled femtosecond laser astigmatic keratotomy for the treatment of high astigmatism post-penetrating keratoplasty.

Purpose: To use beveled femtosecond laser astigmatic keratotomy (FLAK) incisions to treat high astigmatism after penetrating keratoplasty.

Methods: Paired FLAK incisions at a bevel angle of 135 degrees, 65% to 75% depth, and arc lengths of 60 to 90 degrees were performed using a femtosecond laser. One case of perpendicular FLAK was presented for comparison.

Anterior chamber angle measurements using Schwalbe's line with high-resolution fourier-domain optical coherence tomography.

Purpose: To use Fourier-domain optical coherence tomography (OCT) to measure the angle opening distance at Schwalbe's line (AOD-SL) and determine its value in anterior chamber angle assessment.

Methods: Horizontal scans of the nasal and temporal anterior chamber angles in glaucoma subjects were performed at 830 nm wavelength Fourier-domain OCT. Images were graded by 2 ophthalmologists who assessed the visibility of Schwalbe's line (SL), anterior limbus (AL), scleral spur (SS), and angle recess (AR).

Intraocular lens power calculation after previous myopic laser vision correction based on corneal power measured by Fourier-domain optical coherence tomography.

Purpose: To use Fourier-domain optical coherence tomography (OCT) to measure corneal power and calculate intraocular lens (IOL) power in cataract surgeries after laser vision correction.

Setting: Doheny Eye Institute, Los Angeles, California, and Cullen Eye Institute, Houston, Texas, USA.

Design: Prospective comparative case series.