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Optometry & Vision Science - Published Ahead-of-Print
Tue, 09 Feb 2010 00:30:30 -0600
The corneal endothelium maintains stromal deturgescence, which is a prerequisite for corneal transparency. The principal challenge to stromal deturgescence is the swelling pressure associated with the hydrophilic glycosaminoglycans in the stroma. This negative pressure induces fluid leak into the stroma from the anterior chamber, but the rate of leak is restrained by the tight junctions of the endothelium. This role of the endothelium represents its barrier function. In healthy cornea, the fluid leak is counterbalanced by an active fluid pump mechanism associated with the endothelium itself. Although this pump-leak hypothesis was postulated several decades ago, the mechanisms underlying regulation of the balance between the pump and leak functions remain largely unknown. In the last couple of decades, the ion transport systems that support the fluid pump activity have been discovered. In contrast, despite significant evidence for corneal edema secondary to endothelial barrier dysfunction, the molecular aspects underlying its regulation are relatively unknown. Recent findings in our laboratory, however, indicate that barrier integrity (i.e., structural and functional integrity of the tight junctions) of the endothelium is sensitive to remodeling of its peri-junctional actomyosin ring, which is located at the apical junctional complex. This review provides a focused perspective on dynamic regulation of the barrier integrity of endothelium vis-a-vis plasticity of the peri-junctional actomyosin ring and its association with cell signaling downstream of small GTPases of the Rho family. Based on findings to date, it appears that development of specific pharmacological strategies to treat corneal edema in response to inflammatory stress would be possible in the near future. (C) 2010 American Academy of Optometry
Purpose. Patient-reported outcomes are traditionally measured with questionnaires and many have been developed to measure Vision-Related Activity Limitation (VRAL; visual disability or visual functioning), Symptoms, and Quality Of Life (QOL). These vary in quality and can be classified as First or Second Generation instruments. First generation instruments are characterized by simple summary scoring of ordinal responses, which precludes interval measurement. This problem is solved in second generation instruments where Rasch analysis is used to optimize psychometric properties. However, second generation instruments retain limitations; difficulties in comparing scores across instruments, limited applicability to populations and inability to adapt to change. A third generation approach to patient-reported outcomes measurement, item banking, can solve these problems. The aim of this project was to use Rasch analysis to calibrate all items from all instruments to form VRAL, Symptoms, and QOL Item Banks. Methods. Six hundred twenty-four people on the waiting list for cataract surgery were recruited. Each participant completed, by self-administration, a number of the 19 instruments. A total of 353 items were calibrated using Rasch analysis (Winsteps v3.67). The psychometric properties of each item bank were optimized; items fitting the Rasch model were retained (Infit and Outfit range, 0.50 to 1.50). Results. Items were sorted into the three traits; 226 tapped VRAL, 22 symptoms, and 60 QOL. Satisfactory measurement of each latent trait occurred with person separation of 8.11 for VRAL, 2.33 for Symptoms, and 3.20 for QOL. Rasch estimates of item difficulty were highly stable with an average standard error of 0.11 logits. Conclusions. Item banks for the measurement of the latent traits of VRAL, symptoms, and QOL have been formed. New items can be added to enable evolution of measurement. Item banking facilitates accurate and precise measurement through computer adaptive testing. This approach provides common measurement scales, facilitating worldwide comparison of results. (C) 2010 American Academy of Optometry
Purpose. Seven existing and three new image quality metrics were evaluated in terms of their effectiveness in predicting subjective cycloplegic refraction. Methods. Monochromatic wavefront aberrations (WA) were measured in 70 eyes using a Shack-Hartmann based device (Complete Ophthalmic Analysis System; Wavefront Sciences). Subjective cycloplegic spherocylindrical correction was obtained using a standard manifest refraction procedure. The dioptric amount required to optimize each metric was calculated and compared with the subjective refraction result. Metrics included monochromatic and polychromatic variants, as well as variants taking into consideration the Stiles and Crawford effect (SCE). WA measurements were performed using infrared light and converted to visible before all calculations. Results. The mean difference between subjective cycloplegic and WA-derived spherical refraction ranged from 0.17 to 0.36 diopters (D), while paraxial curvature resulted in a difference of 0.68 D. Monochromatic metrics exhibited smaller mean differences between subjective cycloplegic and objective refraction. Consideration of the SCE reduced the standard deviation (SD) of the difference between subjective and objective refraction. Conclusions. All metrics exhibited similar performance in terms of accuracy and precision. We hypothesize that errors pertaining to the conversion between infrared and visible wavelengths rather than calculation method may be the limiting factor in determining objective best focus from near infrared WA measurements. (C) 2010 American Academy of Optometry
Purpose. To use psychophysical scaling to investigate if the inclusion of reference anchors affected the perceived redness of the reference images of four bulbar redness grading scales and to convert grades between scales. Methods. Ten participants were asked to arrange printed copies of the McMonnies/Chapman-Davies (6), IER (4), and Efron (5) grading scale images relative to each other, using the stationary but unlabeled 10, 30, 50, 70, and 90 reference images of the validated bulbar redness scale as additional anchors within a given 0 (minimum) to 100 (maximum) redness range (anchored scaling). The position of each image was averaged across observers to represent its perceived redness within this range. Anchored scaling data were then compared with data from a previous study, where the images of all four grading scales had been scaled for the same experimental setup, but with no reference anchors provided (non-anchored scaling). Averaged perceived redness as determined with anchored scaling was used to cross-calibrate grades between scales. Results. Overall, perceived redness of the reference images was significantly different within each scale (repeated measures analysis of variance, all scales p <0.001). There were differences in perceived redness range and when comparing reference levels between scales. Anchored scaling resulted in an apparent shift to lower perceived redness for all but one reference image compared with non-anchored scaling, with the rank order of the 20 images for both procedures remaining fairly constant (Spearman's [rho] = 0.99). Conclusions. The re-scaling of the reference images in the anchored scaling experiment suggests that redness was assessed based on within-scale characteristics and not using absolute redness scores, a mechanism that can be referred to as clinical scale constancy. The perceived redness data allow practitioners to modify the grades of the scale they commonly use for comparison of their grading estimates with grades obtained with another calibrated scale. (C) 2010 American Academy of Optometry
Purpose. To study the usefulness of the Waveform Score from the ocular response analyzer (ORA). Methods. Both eyes of sixty-four normal Chinese adults were measured by the ORA. An experienced practitioner who was masked to the score evaluated the waveforms. Four measurements were obtained from each eye, and the average was considered as the gold standard. Agreement was compared for the mean of different multiple measurements to the gold standard. Results. There was no significant difference between the gold standard and the mean of different multiple measurements for all ORA parameters. The Waveform Score of 512 signals (four measurements from each eye of 64 subjects) ranged from 1.58 to 9.06. When the best signal value of four measured signals from each eye was considered, the lowest score was 3.60 from 128 eyes. The lower 10th percentile from all signals had Waveform Scores <3.48. Conclusions. If the Waveform Score provides information on the reliability of the signals, a score <3.50 may indicate an unreliable signal, and the signal should be discarded. We also recommend taking three measurements with all the signals having a Waveform Score of 3.50 or above to increase the precision. (C) 2010 American Academy of Optometry
Purpose. To compare the repeatability of the alternate cover test between experienced and inexperienced examiners and the effects of dissociation time and examiner bias. Methods. Two sites each had an experienced examiner train 10 subjects (inexperienced examiners) to perform short and long dissociation time alternate cover test protocols at near. Each site conducted testing sessions with an examiner triad (experienced examiner and two inexperienced examiners) who were masked to each other's results. Each triad performed the alternate cover test on 24 patients using both dissociation protocols. In an attempt to introduce bias, each of the paired inexperienced examiners was given a different graph of phoria distribution for the general population. Analysis techniques that adjust for correlations introduced when multiple measurements are obtained on the same patient were used to investigate the effect of examiner and dissociation time on each outcome. Results. The range of measured deviations spanned 27.5 prism diopters ([DELTA]) base-in to 17.5[DELTA] base-out. The absolute mean difference between experienced and inexperienced examiners was 2.28 +/- 2.4[DELTA] and at least 60% of differences were <=2[DELTA]. Larger deviations were measured with the long dissociation protocol for both experienced and inexperienced examiners (mean difference range = 1.17 to 2.14[DELTA], p < 0.0001). The percentage of measured small deviations (2[DELTA] base-out to 2[DELTA] base-in) did not differ between inexperienced examiners biased with the narrow vs. wide theoretical distributions (p = 0.41). The magnitude and direction of the deviation had no effect on the size of the differences obtained with different examiners or dissociation times. Conclusions. Although inexperienced examiners differed significantly from experienced examiners, most differences were <2[DELTA] suggesting good reliability of inexperienced examiners' measurements. Examiner bias did not have a substantial effect on inexperienced examiner measurements; however, increased dissociation resulted in larger measured deviations for all examiners. (C) 2010 American Academy of Optometry
Purpose. To describe features associated with the development and resolution of peripapillary retinoschisis with an underlying serous detachment in a patient with primary open angle glaucoma. This presentation occurred in the absence of an observed optic nerve coloboma, congenital, or acquired optic nerve head pit. Case Report. A patient with advanced glaucomatous optic nerve cupping developed a temporally localized peripapillary serous detachment in the right eye which spontaneously resolved. Results. Optical coherence tomography demonstrated an area of retinoschisis with underlying serous detachment contiguous with the temporal disc margin. Although fluorescein angiography was not performed and the presence of a peripapillary subretinal neovascular membrane could not be ruled out, an atypical coloboma, optic nerve head pit, or peripapillary subretinal neovascular membrane was not observed during biomicroscopy or scanning laser ophthalmoscopy. The retinoschisis and detachment resolved without intervention. Conclusion. Peripapillary retinoschisis with an underlying serous detachment may develop in subjects with advanced glaucoma. Although the occurrence of the findings in this case may be unrelated to glaucomatous optic neuropathy, the likelihood that a pathogenic mechanism linked to advanced glaucoma may be responsible for the development of peripapillary schisis and serous detachment should alternatively be taken into consideration. This case documents its spontaneous resolution without intervention. (C) 2010 American Academy of Optometry
Twenty years of investigation into emmetropization and the development of myopia has led to several recent insights. Accommodation appears to be an important visual signal for emmetropization. Lens thinning during emmetropization and its cessation at the onset of myopia suggest that interruption of lens stretch during growth is an important part of the process of developing myopia. The ciliary muscle may play a greater role in emmetropization and myopia than previously thought. Time spent outdoors, not near work, may be the more important environmental variable in myopia. The effect of time outdoors shows an important interaction with a substantial genetic contribution to the risk of myopia. (C) 2010 American Academy of Optometry
Purpose. To evaluate the frequency level and profile of contact lens storage case contamination in asymptomatic contact lens wearers and to examine whether different areas of the same lens case may show a different rate and profile of contamination. The relationship between lens storage case contamination and the age of the lens storage case was also examined. Methods. Sixty-four lens cases and case age information were collected from asymptomatic contact lens wearers. Lens cases were sampled at two locations, the upper rim and the lower base. The samples underwent microbiological investigation for recovery of bacteria and fungi. Contamination rate between the two sampling locations and the relationship between the contamination levels and the age of the lens case were analyzed. Results. Contamination occurred in 58% (37 of 64) of lens cases. The most frequently recovered microorganisms were coagulase-negative Staphylococci (51%, 19 of 37), Bacillus spp. (43%,16 of 37), and fungi (27%,10 of 37). For flat-well lens cases, higher numbers of microorganisms were recovered from the upper rim than that from the lower base (p = 0.02), and a greater variety of Gram-negative bacteria were recovered from the upper rim. A higher recovery rate of Micrococcus spp. (p = 0.02; in flat cases) and coagulase-negative Staphylococci (p = 0.01; for both flat and basket type cases) was found from the base of the case well compared with the upper rim. For stand-up cases, higher numbers of microorganisms were recovered from the lens basket compared to the upper hinge (p = 0.047). Lens cases that were <9 months of age had lower levels of contamination (p = 0.013) than older cases. Conclusions. Frequent replacement of lens cases may reduce microbial contamination. Future studies should specify the areas swabbed in the lens case. Better lens storage case design and additional hygiene attention need to be introduced to reduce contamination in these "risky" areas. (C) 2010 American Academy of Optometry
A significant factor in the continuing development and maturation of professional optometry in the early twentieth century was book and journal literature. Some of the prominent optometric writers of that era do not seem to be remembered today. Two examples are Robert Minturn Lockwood (1857-1920) and George A. Rogers (1852-1935). This article provides biographical sketches of each of them and brief descriptions of the contents of the books they published. (C) 2010 American Academy of Optometry
Purpose. This observational case series investigated the occurrence and distribution of proptosis in Japanese patients with dysthyroid ophthalmopathy (DO). The relationship among lid retraction, lid swelling, and enlargement of extraocular muscles was also analyzed. Methods. From 1993 to 2002, 10 931 patients (2240 men and 8691 women, average age; 39.9 +/- 14.0 years) with abnormal thyroid function were examined for proptosis. Proptosis was measured using a Hertel exophthalmometer, and lid swelling and retraction were classified. Orbital magnetic resonance imaging or computed tomography was used to quantify enlargement of the extraocular muscles. Results. Clinically significant proptosis (>=15 mm) was present in 74.2% patients and was classified as mild (15-17 mm, 39.1%), moderate (18-20 mm, 25.9%), or severe (>20 mm, 9.2%). The average exophthalmometer reading was 17.2 +/- 3.2 mm, with proptosis less pronounced with age (p < 0.001) and more pronounced in men than women (18.2 +/- 3.4 mm vs. 17.0 +/- 3.1 mm; p < 0.001). Lid retraction was present in 57.7% of patients, lid swelling in 46.9%, and muscle enlargement in 40.8% of patients. Multiple regression analysis revealed proptosis was strongly correlated with a young age and the male gender, followed by extraocular muscle enlargement and lid retraction and swelling (p < 0.001). Conclusions. This study assessed the measurable features of proptosis in Japanese patients with DO and contributes to the understanding by correlating symptoms and signs of DO. (C) 2010 American Academy of Optometry
Purpose. In the developing world, refractive error is a common untreated cause of visual impairment. Lay people may use portable tools to overcome this issue. This study compares three methods of measuring spherical refractive error (SE) performed by a lay technician to a subjective refraction (SR) in a controlled clinical setting and a field trial. Methods. Fifty subjects from Boston, MA (mean age, 24.3 y +/- 1.5) and 50 from Nicaragua (mean age, 40 y +/- 13.7) were recruited. Measures (performed on right eye only) included (1) AdSpecs, adjustable spectacles; (2) Focometer, focusable telescope; (3) Predetermined Lens Refraction (PLR), prescripted lens choices; (4) SR. Examiners were masked and techniques randomized. Student t-test compared mean SE determined by each method (95% confidence intervals). AdSpecs repeatability was evaluated by repeating measures of SE and visual acuity (VA). Results. Mean (SD) SE for Boston subjects determined by SR was -2.46 D (3.2). Mean (SD) SE for AdSpecs, Focometer -2.41 D (2.69), -2.80 D (2.82). Among the 30 Boston subjects considered in analyses of PLR data (see Methods), PLR and SR obtained mean (SD) values of -0.65 D (1.36) and -0.41 D (1.67), respectively, a statistically significant difference of -0.24 D (p = 0.046, t = 2.09). Mean PLR SE had greatest deviation from SR, 0.67 D. 20/20 VA was achieved by SR, AdSpecs, Focometer, and PLR in 98, 88, 84, 96% of subjects. Mean (SD) SE for Nicaragua subjects determined by SR was +0.51 D (0.71). Mean (SD) SE for AdSpecs, Focometer, and PLR was +0.68 D (0.83), +0.42 D (1.13), +0.27 D (0.79). Mean PLR SE had the greatest deviation from the SR by 0.24 D, which was a statistically significant difference. 20/20 VA was achieved by SR, AdSpecs, Focometer, and PLR in 78, 66, 66, 88% of subjects. Repeated measures by AdSpecs were highly correlated. Conclusions. Although the mean value obtained by each technique may be similar to that obtained by SR, substantial and clinically meaningful differences may exist in some individuals; however, where SR is unavailable they could be a feasible alternative. (C) 2010 American Academy of Optometry
The development of treatments that slow photoreceptor death could profoundly improve patient wellbeing in those with inherited retinal degenerations. Over recent years, it has emerged that extracellular adenosine-tri-phosphate (ATP) regulates the function of photoreceptors in rodents and primates. Moreover, when the retina is exposed to high levels of ATP, rapid death of photoreceptors occurs, which can be blocked by pretreatment with antagonists to P2X receptors. Compounds that inhibit the action of extracellular ATP slow photoreceptor loss in an animal model of inherited retinal degeneration. In this article, I provide an overview of our work in relation to other research in this area and suggest a model by which ATP contributes to photoreceptor death in inherited retinal degenerations. (C) 2010 American Academy of Optometry
People with central vision loss must use peripheral vision for visual tasks. It is well known that performance for almost all spatial tasks is worse in the normal periphery than in the normal fovea. The primary goal of my ongoing research is to understand the limiting factors and the potential for enhancing vision for people with central vision loss. Here I review my previous work related to understanding the limiting factors on reading, a task that is the primary complaint of many patients with age-related macular degeneration, the leading cause of visual impairment in the elderly. I also review my work related to enhancing visual functions in the normal periphery and how it may be applied to people with central vision loss. (C) 2010 American Academy of Optometry
A devastating consequence of autoimmune-mediated, aqueous tear deficiency is pathological keratinization of the ocular surface. It is setoff by an aberrant immune response that promotes a program of altered mucosal epithelial cell differentiation. The management of keratinizing ocular surface disease is challenging. Topical therapies are largely inadequate for acute exacerbations, and progressive disease often requires systemic immunosuppression. A combination of translational and basic science research is necessary to understand the link between aberrant immunity and pathological keratinization. I review recent research and future directions aimed to develop targeted therapies that control or prevent ocular surface keratinization. (C) 2010 American Academy of Optometry

Published monthly, Optometry and Vision Science (OVS) is the official journal of the American Academy of Optometry. It is an authoritative source for current developments in optometry, physiological optics, and vision science. Ranked 19th, and the top ranked optometry journal internationally of the top 45 journals in the Ophthalmology (eye/vision research, ophthalmology, optometry) category (JCR, 2007) with an Impact Factor of 1.638, this frequently cited scientific journal has served primary eye care practitioners for almost 80 years, promoting vital interdisciplinary exchange among optometrists, ophthalmologists and vision scientists worldwide. Anthony J. Adams, OD, PhD, FAAO is the Editor-in-Chief, Optometry and Vision Science.


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This is a PDF document list of all of the Program Numbers for Academy 2005 San Diego. The format of the program numbers is described below.

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The Academy's scientific papers and posters can be cited using a program number in which the first two digits are the year (i.e. "05", for 2005). The next digit is either "0" (for papers), or "5" (for posters). The next three digits are the placement of the papers or posters in the meeting. The 2005 meeting includes the numbers 001 to 103 for papers, and 001 to 436 for posters.


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Before 2005:
Omlor RA, Mutti DO. Differences in axial length using A-scan ultrasonography and IOL Master: effects of anterior chamber depth. Optom Vis Sci 2003;80(suppl.):120.

Beginning 2005:
Author, VS. The effect of all-work and no-play on peripheral vision. Optom Vis Sci 2005;82:E-abstract 050437.
[The OVS volume changes each year with year 2005 being 82; hence "Optom Vis Sci 2005;82" in the citation.]

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