IN THIS ISSUE:
• New Clinical Test of Amblyopia for Infants and Toddlers
Amblyopia is considered a visual cortex anomaly. Vernier acuity tasks, which depend on intact visual cortex, are candidates for screening amblyopia. The authors developed vernier acuity cards specifically for infants and toddlers and evaluated their screening validity by testing children old enough to complete optotype acuity testing. The result? Their vernier acuity cards gave good sensitivity, specificity, and accuracy as a tool to detect amblyopia in young children. (p. 806)
• Can Quality of Life be Measured for Young Children with Refractive Errors?
Perhaps! But, our authors, from a number of different regions of the world, found that the Pediatric Quality of Life Inventory (PedsQL 4.0) was not a valid psychometric scale to evaluate the impact of refractive errors in preschool children at the site of their study (Singapore). (p. 813)
• Distinguishing Theories of Juvenile-Onset Myopia
The baseline data, of a 2-year larger study, suggest that there is a relative refraction asymmetry between the horizontal meridian (relative hyperopic defocus) and vertical meridian (relative myopic defocus) of uncorrected eyes of myopic children. Because myopic defocus is believed to be an ocular growth “stop” signal, this finding has implications regarding the role that peripheral defocus might play in myopia onset and progression. (p. 823)
• Postoperative Accommodation Problems may be Permanent after Photorefractive Keratectomy (PRK) in Myopic Eyes
Some of the PRK postoperative near vision problems in myopic patients younger than 30 are probably due to a decrease in amplitude of accommodation (AA) and facility of accommodation (FA). The authors report that AA and FA eventually increase after 3 months. However, in older patients, despite increase in FA, AA does not change after surgery. (p. 833)
• How Do Lens Care Products Impact Conjunctiva and Comfort of Silicone Hydrogel Lenses?
Contact lenses soaked in either multipurpose solution containing PHMB or Polyquad/Aldox were worn for 1 day and corneal and conjunctival clinical variables, as well as symptomatology, were compared with lenses worn direct from the packaging. The authors found that lens care products can change corneal staining and comfort responses during wear. These changes may be associated with release of material soaked into lenses or changes to the lens surface composition. (p. 839)
• Risk Factors for 30-Night Extended Wear in India
This large-scale interventional study, conducted in Hyderabad, India, investigated the risk factors for corneal inflammatory and mechanical events in wearers of silicone hydrogel lenses on a 30-night extended wear schedule. The study found that a multitude of factors, including job/environment, lens contamination, vascularization, and lens movement, contribute to the development of adverse events. (p. 847)
• Proteomic Analysis and Protein Extraction from Tears and Contact Lenses
Four protein extraction and precipitation methods commonly used in proteomic analyses were compared for optimal yield of available tear protein. Tear samples subjected to any of the four chemical treatments provided significantly less protein than untreated samples. For contact lenses, trifluoroacetic acid/acetonitrile extraction provided the highest yield of available protein of the four treatments evaluated. (p. 854)
• An Error of “Clinical Wisdom” Revealed with LASIK Outcomes of Acuity
The authors tested the clinical wisdom regarding custom (wavefront-guided) laser in situ keratomileusis (LASIK) that individuals with better-than-average best-corrected visual acuity (BCVA) before surgery have a greater risk of losing BCVA postoperatively than do individuals with worse-than-average BCVA before surgery. However, the authors conclude that this clinical observation is due to a statistical artifact (regression to the mean) and is not attributable to the surgery. (p. 861)
• Reliably Measuring Choroidal Thickness
Our authors find good repeatability and reproducibility of the subfoveal choroidal thickness calculations performed manually using spectral-domain optical coherence tomography (OCT) Copernicus (SOCT) in healthy Caucasian eyes. Interestingly, their preliminary results suggest a negative correlation between subfoveal choroidal thickness and axial length so that choroidal thickness decreases with increasing axial length but not with refractive error. (p. 867)
• New Instrument Allows Dynamic and Static Accommodation Measures in Presbyopic “Restoration” Treatments
Reliable and practical clinical methods of objective accommodation measurement for presbyopic “restoration” treatments are needed to evaluate the efficacy of these procedures. Although accommodation is a dynamic process, objective clinical accommodation measurement has typically been static. A new version of the Grand Seiko autorefractor (WAM-5500) can perform static and dynamic refraction measurements. The authors provide a simple protocol that can be used for reliable and repeatable static and dynamic clinical accommodative measurements. (p. 873)
• Can Aniseikonia be Measured Accurately and Reliably in Children?
Residual amblyopia is a significant problem and aniseikonia, a perception of unequal image size, may be one factor that limits visual improvement. The authors claim that, to date, no instrument to measure aniseikonia in children has been shown to be accurate and reliable. Here, they report that children as young as 6 years can make the instrument adjustments to measure aniseikonia under dissociated conditions. They do this with sufficient accuracy and reliability to make the Aniseikonia Inspector software (version 1) clinically useful. (p. 883)
• How Vulnerable are Higher Order Aberrations of the Eye to Blur?
Our authors studied the effects of blur on the optical aberrations of the eye for a range of higher order aberrations while subjects viewed a high contrast visual acuity chart. They found that subjective blur limits increase more quickly for the higher order aberrations than for simple defocus as the criterion changed from “just noticeable” to “just troublesome” and then to “just objectionable.” (p. 890)
• Visual Impairment: a New Measure of a Patient's Adaptation to Life
A patients' adaptation to life with visual impairment is an outcome measure for assessing the success of interventions. Here, the authors refine, using Rasch analysis, an existing selfreport questionnaire (“Nottingham Adjustment Scale”) to produce a 19-item instrument named the Acceptance and Self-Worth Adjustment Scale (AS-WAS). Performance of the revised instrument as an interval scale measure of adjustment to visual impairment shows promise. (p. 899)
• New Successes in Tackling Bacterial Resistance in Conjunctivitis
Bacterial conjunctivitis can be effectively treated with a range of topical ocular antibiotics by reducing the time course of the disease, preventing the spread of infection, and helping patients return to school or work. However, increasing antibiotic resistance by the bacteria that cause eye infections has recently begun narrowing treatment options. In this review, the authors note that fluoroquinolones, especially newer fluoroquinolones introduced in the past few years, are less likely to be affected by bacterial resistance. (p. 908)