Habitual higher order aberrations affect Landolt but not Vernier acuity.

To assess whether the eye's optical imperfections are relevant for hyperacute vision, we measured ocular wave aberrations, visual hyperacuity, and acuity thresholds in 31 eyes of young adults. Although there was a significant positive correlation between the subjects' performance in Vernier- and Landolt-optotype acuity tasks, we found clear differences in how far both acuity measures correlate with the eyes' optics. Landolt acuity thresholds were significantly better in eyes with low higher order aberrations and high visual Strehl ratios (r2 = 0.

Corneal endothelial cell loss after Baerveldt glaucoma drainage device implantation in the anterior chamber.

Purpose: To investigate central and peripheral corneal endothelial cell density (ECD) in relation to Baerveldt (BV) glaucoma drainage device (GDD) tube corneal (TC) distance.

Methods: Prospective study of all patients scheduled for glaucoma tube surgery with 36 months follow-up. A BV GDD was inserted into the anterior chamber (AC).

Phakic intraocular lens: Two-year results and comparison of endothelial cell loss with iris-fixated intraocular lenses.

Purpose: To evaluate the efficacy, safety, and stability of a foldable angle-supported Acrysof Cachet phakic intraocular lens (pIOL) to correct moderate to high myopia and compare endothelial cell loss after iris-fixated Artisan and Artiflex pIOL implantation.

Setting: University Eye Clinic Maastricht, the Netherlands.

Design: Retrospective observational study.

Reproducibility of anterior chamber angle analyses with the swept-source optical coherence tomography in young, healthy Caucasians.

Purpose: To assess the reproducibility of iridocorneal angle (ICA) analysis in young, healthy Caucasian subjects using swept-source optical coherence tomography (SS-OCT) by determining variability and interobserver agreement between expert and nonexpert observers.

Methods: Thirty-one healthy volunteers (nonexperts) acquired three consecutive SS-OCT images of the right eyes of their peer nonexperts. Images were analyzed by 31 nonexperts and additionally by three experts, whereby the angle opening distance (AOD) and the trabecular iris space area (TISA) at 500 and 750 μm were calculated.

Baerveldt drainage tube motility in the anterior chamber.

Purpose: To investigate the stability in position of the Baerveldt glaucoma drainage tube over time and to study movement of the drainage tube in the anterior chamber (AC) under varying light conditions.

Methods: This prospective study included 70 eyes with implantation of a Baerveldt glaucoma drainage tube in the anterior chamber. Anterior segment optical coherence tomography (AS-OCT) images were made preoperatively to quantify AC depth.

Consensus on recording of gas permeable contact lens fit.

Purpose: To develop a new schematic scheme for efficiently recording the key parameters of gas permeable contact lens (GP) fits based on current consensus.

Methods: Over 100 established GP fitters and educators met to discuss the parameters proposed in educational material for evaluating GP fit and concluded on the key parameters that should be recorded. The accuracy and variability of evaluating the fluorescein pattern of GP fit was determined by having 35 experienced contact lens practitioners from across the world, grading 5 images of a range of fits and the topographer simulation of the same fits, in random, order using the proposed scheme.

Comparability and repeatability of corneal astigmatism measurements using different measurement technologies.

Purpose: To determine the comparability and repeatability of corneal astigmatism measurements obtained with different devices and determine the interobserver variability of a new automated keratometer.

Setting: University Eye Clinic Maastricht, the Netherlands.

Design: Prospective cohort study.

Detection of Raman spectra in ocular drugs for potential in vivo application of Raman spectroscopy.

Purpose: Raman spectroscopy holds potential for the assessment of intraocular pharmacokinetics. Raman spectra of ocular drugs were acquired, to determine the drug-specific Raman signature. The ability of the Raman technique to quantify drug concentrations was also investigated.

Dissatisfaction after implantation of multifocal intraocular lenses.

Purpose: To analyze the symptoms, etiology, and treatment of patient dissatisfaction after multifocal intraocular lens (IOL) implantation.

Setting: Department of Ophthalmology, Maastricht University Medical Center, The Netherlands.

Design: Case series.

Evaluation of the comparability and repeatability of four wavefront aberrometers.

Purpose: To compare total ocular aberrations and corneal aberrations identified with four different aberrometers and to determine the repeatability and interobserver variability.

Methods: In this prospective comparative study, 23 healthy subjects underwent bilateral examination with four aberrometers: the Irx3 (Hartmann-Shack; Imagine Eyes, Orsay, France), Keratron (Hartmann-Shack; Optikon, Rome Italy), iTrace (ray-tracing; Tracey Technologies, Houston, TX), and OPD-Scan (Automated Retinoscopy; Nidek, Gamagori, Japan). Six images per eye were obtained.

Visual outcome and patient satisfaction after multifocal intraocular lens implantation: aspheric versus spherical design.

Purpose: To evaluate visual outcomes and patient satisfaction after implantation of an aspheric apodized diffractive intraocular lens (IOL) or a spherical apodized diffractive IOL in cataract surgery.

Setting: Maastricht University Medical Center, The Netherlands.

Design: Nonrandomized clinical trial.

Reproducibility of anterior chamber angle measurements with anterior segment optical coherence tomography.

Purpose: To study the reproducibility and variability of iridocorneal angle (ICA) measurements by using anterior segment optical coherence tomography (AS-OCT) by expert and nonexpert observers.

Methods: Twenty-three healthy volunteers (nonexperts with a basic knowledge of ophthalmology) acquired five consecutive AS-OCT images in the enhanced anterior segment single mode in the 180° to 0° meridian of the right eyes of their peers. Two experts and the 23 nonexperts analyzed the images.

Value of optical coherence tomography for anterior segment surgery.

Unlabelled: Anterior segment optical coherence tomography (AS-OCT) is an important new noncontact imaging technology that uses a 1310 nm super luminescent diode. It can be used to assess anterior chamber biometry, corneal thickness, lens thickness, and angle configuration; to visualize pathological processes; to evaluate postsurgical anatomy and posttraumatic eyes; and to image phakic intraocular lenses and intracorneal ring segments. Because it is a noncontact technique, it can also be used intraoperatively, which could be useful during trabeculectomy and after deep anterior lamellar keratoplasty to detect abnormalities in the cornea and interface.

Iris-fixated anterior chamber phakic intraocular lens for myopia moves posteriorly with mydriasis.

Purpose: To elucidate the physiological characteristics of eyes implanted with iris-fixated anterior chamber phakic intraocular lenses (pIOLs), which are increasingly being used for the correction of higher myopic and hyperopic refractive errors.

Methods: In a case series of 20 patients (39 eyes), the position of the pIOL to the natural lens and the cornea was evaluated under photopic (135 lux) and low mesopic (< 1 lux) circumstances with anterior segment optical coherence tomography.

Results: The distance between the pIOL and the natural lens decreased, and congruently, the distance from the pIOL to the corneal endothelium increased under low mesopic circumstances.

Prevalence of habitual refractive errors and anisometropia among Dutch schoolchildren and hospital employees.

Purpose: Refractive error (RE) is suggested to cause not only visual impairment, but also functional problems such as aspecific health complaints and lower levels of school achievement. During the last few decades the prevalence of myopia has increased worldwide, especially in Asia. We investigated the prevalence of habitual RE and anisometropia in a Dutch population of children and employees.

Comparison of central corneal thickness and anterior chamber depth measurements using three imaging technologies in normal eyes and after phakic intraocular lens implantation.

Background: The repeatability and interchangeability of imaging devices measuring central corneal thickness (CCT) and anterior chamber depth (ACD) are important in the assessment of patients considering refractive surgery. The purpose of this study was to investigate the agreement of CCT and ACD measurements using three imaging technologies in healthy eyes and in eyes after phakic intraocular lens implantation (pIOL).

Methods: In this comparative study, CCT and ACD were measured using anterior segment optical coherence tomography (AS-OCT), Orbscan II, and Pentacam in 33 healthy volunteers (66 eyes) and 22 patients (42 eyes) after pIOL implantation.

Evaluation of signs and symptoms in 3- and 9-o'clock staining.

Purpose: This study evaluates the relationship between bulbar hyperemia, conjunctival staining, lens comfort and 3- and 9-o'clock corneal staining in rigid gas permeable (GP) contact lens wear.

Methods: The study involved 55 GP contact lens wearers (with and without 3- and 9-o'clock staining) and 26 non-lens wearers. Corneal staining was graded based on a specially designed image grading scale developed at the University of Maastricht.

Influence of anterior chamber morphometrics on endothelial cell changes after phakic intraocular lens implantation.

Purpose: To analyze the position of iris-fixated phakic intraocular lenses (pIOLs) using anterior segment optical coherence tomography (AS-OCT) and evaluate the effect of anterior chamber morphometrics on endothelial cell changes.

Setting: Department of Ophthalmology, Academic Hospital Maastricht, The Netherlands.

Methods: In this cross-sectional study, AS-OCT was used to measure the distances from the center and the edges of the pIOL to the corneal endothelium in 242 eyes with various models of myopic pIOLs.

Eyeblink frequency and type in relation to 3- and 9-o'clock staining and gas permeable contact lens variables.

Purpose: The primary goal of this study was to evaluate if there is a difference in frequency and in completeness of eyeblinks (type of eyeblink) in rigid gas permeable (GP) lens wearers experiencing 3- and 9-o'clock staining compared with GP lens wearers without substantial staining and nonlens wearers.

Methods: The study involved 26 nonlens wearers and 55 GP contact lens wearers, with and without 3- and 9-o'clock staining. Every eyeblink over a 5-min period was categorized as a complete eyeblink, incomplete eyeblink, or an eyeblink attempt.

Long-term follow-up of a multifocal apodized diffractive intraocular lens after cataract surgery.

Purpose: To report the long-term performance of the AcrySof ReSTOR SA60D3 intraocular lens (IOL) after cataract surgery.

Setting: University Hospital Maastricht, Maastricht, The Netherlands.

Methods: This prospective clinical trial comprised 44 eyes (22 consecutive patients) having cataract surgery with implantation of the ReSTOR IOL.

Comparison of two pupillometers in determining pupil size for refractive surgery.

Purpose: To compare a handheld and a digital pupillometer in determining pupil size in a population of refractive surgery candidates (group 1) and after implantation of an Artisan phakic intraocular lens (PIOL) for correction of myopia (group 2).

Methods: Pupil size was measured with the Colvard and Procyon pupillometers in 121 eyes in group 1 and 83 eyes in group 2. Pupil sizes measured with the Colvard device were compared with the scotopic, mesopic-low and mesopic-high measurements taken with the Procyon pupillometer in both groups.

Relationship between habitual refractive errors and headache complaints in schoolchildren.

Purpose: Refractive error (RE) is considered to be a possible cause for headaches. We aimed to gain insight into the relation between habitual RE (sphere and astigmatism) and headache complaints.

Methods: In a cross-sectional study the habitual refractive state of 487 children, aged between 11 and 13 years, was measured using an autorefractometer (Topcon, RM-8000B).

Evaluation of pupil dynamics after implantation of artisan phakic intraocular lenses.

Purpose: To compare pre- and postoperative horizontal and vertical pupil diameters after horizontal Artisan phakic intraocular lens (PIOL) (Ophtec BV, Groningen, The Netherlands) implantation for correction of myopia.

Methods: The pre- and postoperative scotopic pupil diameters measured by the Colvard pupillometer (Oasis Medical, Glendora, Calif) were compared in 71 eyes after Artisan PIOL implantation (Artisan Colvard group). Analysis of pupil shape (vertical vs horizontal diameter, V/H ratio) after horizontal Artisan PIOL implantation was performed with the Procyon pupillometer (Procyon Instruments Ltd, London, United Kingdom) in 121 eyes (Artisan Procyon group) under scotopic, mesopic-low, and mesopic-high conditions and compared to an age- and refraction-matched control group of 121 eyes of refractive surgery candidates (Procyon control group).

Optimising RGP lens fitting in normal eyes using 3D topographic data.

Purpose: To analyse, retrospectively, the effect of fitting characteristics on comfort of wear and the role that 3D topographic data can play in attaining an optimal lens fit with rigid gas permeable (RGP) contact lenses in normal eyes.

Methods: Included were 60 normal myopic eyes (1.00-5.

Effectiveness of multifocal intraocular lenses to correct presbyopia after cataract surgery: a randomized controlled trial.

Purpose: Although monofocal intraocular lenses (IOLs) are effective in improving vision after cataract surgery, the loss of accommodation is not restored by implantation of these IOLs. Because multifocal IOLs may improve uncorrected distance and near vision, we compared the clinical outcome and patient satisfaction after implantation of monofocal and multifocal IOLs. Sociodemographics, eagerness for spectacle independence (ESI), and neuroticism were tested as predictors of satisfaction.