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Background: The aim was to evaluate the effect of ocular topography on soft contact lens fit in Chinese and Caucasians., Method: This study evaluated 547 subjects from two ethnic groups, Caucasian (n = 250) and Chinese (n = 297), at investigational sites in three locations: Wenzhou, China, Melbourne, Australia and Jacksonville, USA. Subjects underwent measurement of a range of ocular topographic variables using identical equipment and protocols, including: apical corneal radius (CR), corneal shape factor (CSF) in the two principal meridians, horizontal visible iris diameter (HVID), vertical palpebral aperture (PA), upper lid angle (ULA) and inter-canthal angle (ICA). Subjects were fitted with a spherical lens in two base curves (BCs) (1·Day ACUVUE, 8.50, 9.00 mm) and a toric soft lens (Accelerated Stabilization Design)., Results: The steeper base curve (8.50 mm) spherical lenses gave an acceptable overall lens fit with 98 per cent or more of subjects in both groups, while the flatter lens (9.00 mm) was acceptable in a significantly higher proportion of the Chinese compared to Caucasian group (96 versus 82 per cent, p < 0.0001) . The main difference in fit between groups was for centration; there was significantly less decentration with the Chinese group (8.50 BC: 39 versus 72 per cent, p < 0.0001; 9.0 BC: 63 versus. 85 per cent, p = 0.02). The 8.5 mm base curve showed good centration (none or slight decentration) for 97 per cent of Caucasian eyes and 96 per cent of Chinese eyes. With both groups, there were some significant correlations between lens fit and ocular topographic variables, most notable between upper lid angle and toric lens orientation with the Chinese subjects. Regression analysis also showed key predictive values relating to lens fit., Conclusions: Detailed ocular measurements suggest anatomical differences between Chinese and Caucasian populations that should be considered in soft lens design. The spherical and toric lenses tested in this study fitted a large proportion of both Chinese and Caucasian eyes and are robust to the ocular differences noted., (© 2016 Optometry Australia.)

Introduction: This study aimed to compare facial morphologies of an adult African-American population to an adult Caucasian-American population using three-dimensional (3D) surface imaging., Materials and Methods: The images were captured using a stereophotogrammetric system (3dMDface(TM) system). Subjects were aged 19-30 years, with normal body mass index and no gross craniofacial anomalies. Images were aligned and combined using RF6 Plus Pack 2 software to produce a male and female facial average for each population. The averages were superimposed and the differences were assessed., Results: The most distinct differences were in the forehead, alar base and perioricular regions. The average difference between African-American and Caucasian-American females was 1·18±0·98 mm. The African-American females had a broader face, wider alar base and more protrusive lips. The Caucasian-American females had a more prominent chin, malar region and lower forehead. The average difference between African-American and Caucasian-American males was 1·11±1·04 mm. The African-American males had a more prominent upper forehead and periocular region, wider alar base and more protrusive lips. No notable difference occurred between chin points of the two male populations., Conclusions: Average faces were created from 3D photographs, and the facial morphological differences between populations and genders were compared. African-American males had a more prominent upper forehead and periocular region, wider alar base and more protrusive lips. Caucasian-American males showed a more prominent nasal tip and malar area. African-American females had broader face, wider alar base and more protrusive lips. Caucasian-American females showed a more prominent chin point, malar region and lower forehead.

Purpose: The normal distribution of exophthalmometry measurements in a U.S. pediatric population was determined as a reference for clinical practice., Methods: This was a cross-sectional study, in which 673 normal subjects, between 1 and 17 years of age, randomly selected from patients presenting to our institution, were measured with an exophthalmometer. Normal volunteers also participated at a booth at the annual state fair. Subjects were excluded for a prior history of orbital tumor, craniofacial anomaly, thyroid disease, orbital trauma, or inability to tolerate the measurement., Results: A total of 673 subjects (52% female) with a mean age of 9.6 years were studied. There was no difference in exophthalmometric measurements between male and female subjects. Mean exophthalmometric measurements increased with age: less than 4 years old (13.2 mm), 5-8 years old (14.4 mm), 9-12 years old (15.2 mm), and 13-17 years old (16.2 mm). Asymmetric measurements occurred in 100 (14.9%) subjects, with a 2-mm maximal difference in 2 subjects., Conclusion: Exophthalmometric measurements vary with age among the pediatric population. Reference data are presented for each age group in a U.S. cohort.

Background: Short palpebral fissure lengths (PFL) are one of three facial features that define the unique facial phenotype of fetal alcohol syndrome (FAS). Published PFL growth charts vary greatly in both rate and magnitude of growth, placing their accuracy and validity in question. New PFL growth charts were recently published to reflect a racial/ethnic cross section of Canadian girls and boys 6-16 years of age. PFLs were measured from digital facial photographs using the FAS Facial Photographic Analysis Software., Objectives: Assess the goodness of fit of two U.S. populations (healthy children and children with prenatal alcohol exposure) when plotted on the Canadian, Hall, and other published PFL charts., Methods: The PFLs of 106 healthy children and 822 children with prenatal alcohol exposure from Washington State were measured from digital facial photographs using the FAS Facial Photographic Analysis Software. Goodness of fit was assessed graphically and by computation of the mean PFL z-score., Results: Our predominantly Caucasian, healthy group of children scattered along the mean growth curve on the Canadian charts (mean PFL z-score +0.2), and fell 1.6 SDs below the mean on the Hall chart (mean PFL z-score -1.6). The mean PFL z-score for the children with FAS was 2.4 SDs below the mean on the Canadian charts and 3.9 SDs below the mean on the Hall chart. African Americans were not a good fit., Conclusion: The Canadian PFL charts were a good fit for our predominantly Caucasian populations of healthy U.S. school-aged children. Children with FAS continued to present with PFLs 2 or more SDs below the mean when plotted on the Canadian PFL charts, supporting the FAS PFL diagnostic criteria used by the FASD 4-Digit Diagnostic Code. Use of PFL charts normed for African Americans is recommended. Updated PFL charts for 0-6 years of age are vital to prevent an artificial over-estimation of short PFLs in this age group.

Purpose: This cross-sectional report includes ocular component data as a function of age, gender, and ethnicity from the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study., Methods: The ocular components of 4881 school-aged children were examined using cycloplegic autorefraction (refractive error), keratometry (corneal curvature), ultrasonography (axial dimensions), and videophakometry (lens curvature)., Results: The average age (+/-SD) was 8.8 +/- 2.3 years, and 2457 were girls (50.3%). Sixteen percent were African-American, 14.8% were Asian, 22.9% were Hispanic, 11.6% were Native American, and 34.9% were White. More myopic/less hyperopic refractive error was associated with greater age, especially in Asians, less in Whites and African Americans. Corneal power varied slightly with age, with girls showing a greater mean corneal power. Native-American children had greater corneal toricity with a markedly flatter horizontal corneal power. Anterior chambers were longer with age, and boys had deeper anterior chambers. Native-American children had the shallowest anterior chambers and Whites the deepest. Girls had higher Gullstrand and calculated lens powers than boys. Boys had longer vitreous chambers and axial lengths, and both were longer with age. Native Americans had the longest vitreous chambers and Whites the shortest., Conclusions: Most ocular components showed little clinically meaningful variation by ethnicity. The shallower anterior chambers and deeper vitreous chambers of Native-American children appeared to be offset by flatter corneas. The relatively deeper anterior chambers and shallower vitreous chambers of White children appeared to be offset by steeper corneas. Asian children had more myopic spherical equivalent refractive errors, but for a given refractive error the ocular parameters of Asian children were moderate in value compared with those of other ethnic groups. Asian children may develop longer, myopic eyes more often than other ethnic groups, but the eyes of Asian emmetropes do not appear to be innately longer.

Introduction: The international literature seldom refers to eye measurements of the black African patient. Therefore, the various patterns where biometry elements are used as constituents deserve reconsideration as they may not correspond to the eye of the black patient of our region. This study provides true measurements for the black African patient in Ivory Coast. It also establishes hypotheses by extrapolating the role of measurements in pathologies such as glaucoma., Material: and method: The study included 325 eyes of 217 male and female patients. All the patients underwent ocular keratometrics and echo biometrics to measure the depth of the anterior chamber, the width of the lens, and the total axial length with the ultrascan biometer using the contact method in A echometrics., Results: The mean keratometry in women was significantly higher than in men (43.99 +/- 1.62 diopters vs 43.46 +/- 1.45 diopters). The anterior chamber was deeper in men (2.69 mm +/- 0.54 vs 2.53 mm +/- 0.48). The men's eyes were significantly longer, with an axial length of 23.26 mm +/- 1.07 vs 22.56 mm +/- 0.90., Conclusion: Significant biometric differences between men's and women's eyes, on the one hand, and between black African and white patients' eyes, on the other hand, can be observed. The reasons for these differences are several: they are natural, socioeconomic, and technical. If standard implant of a different power for black and white patients can be imagined, can we also infer that the biometrics of a black African patient predisposes him to a disorder such as glaucoma more than a white patient? Further in-depth studies could provide an answer to this question.

It is possible that many patients avoid complete ophthalmic exams because pupil dilation is slow, reversal sluggish, and vision blurred. Others experience incomplete dilation during exams or prior to surgery when good dilation is essential to successful outcome. Iontophoresis, the application of low-level electrical current to promote traversal of desired molecules across a boundary, has been used for many years and has recently become common in transdermal drug delivery. We now investigate iontophoresis as a method of accelerating drug absorption into the ocular anterior segment. In vivo rabbit studies assessed iontophoresis effects on the performance of dilators and constrictors. 1-mA and 4-mA direct current levels applied for 2-minute durations yielded dilation time-history measurements. Subsequent in vitro tests at a wide range of current densities showed minimal chemical modifications in ocular pharmaceuticals. Drug samples processed through high-performance liquid chromatography (HPLC) pinpointed minimal structural changes. Detailed in vivo rabbit testing is under way. Using 2 dilators and constrictors in crossed testing with 0.5-mA to 1.25-mA current levels and 20-sec to 60-sec durations, we recorded dilation progress by digital photography. Initial studies showed faster, larger dilations and quicker reversal using iontophoresis. Drug testing showed chemical structures remaining constant for clinically useful current levels, < or = 1 mA (< or = 1.25 mA/cm2 current density). Drug pH and HPLC retention times were constant within this range, and resistivity varied linearly as expected for increasing current. Rabbit testing will quantify improved drug speed and efficacy, validate the charge delivery electrode design, and indicate iontophoretic current and duration for further use. Tested ocular drugs showed no degradation when exposed to clinically useful iontophoretic currents. Preliminary results indicate significant time reductions for dilation and reversal, plus increases in maximum dilation. This procedure may aid clinicians by allowing more rapid complete examinations and surgical preparations for patients. Making dilation more convenient will also improve patient acceptance of exams, aiding earlier detection and treatment of ocular disease.

It is the committee's recommendation that the ophthalmic community use the line of sight as the reference axis for the purposes of calculating and measuring the ocular optical aberrations.

Results of refractive component measurements have shown that eyes of Melanesian schoolchildren living in Vanuatu, almost all of whom are emmetropic, have relatively short axial lengths and relatively flat corneas in comparison to emmetropic eyes of children examined in England. Evidence is presented to suggest that the relation between the axial length of the eye and corneal radius--the axial length/corneal radius (AL/CR) ratio--may be a useful predictor of future refractive state. Mean axial length/corneal radius ratios for 6- to 19-year-old Melanesian school children were found to be 2.88 for boys and 2.86 for girls, as compared to mean AL/CR ratios for 6- to 19-year-old British schoolchildren of 3.05 for boys and 3.04 for girls. It is proposed that an eye having a high AL/CR ratio is at risk for the development of myopia, and that such an eye has maintained its state of emmetropia by virtue of a compensatory flattening of the crystalline lens. In order to test the proposition that an increase in axial length occurs as a precursor to the development of myopia, a prospective longitudinal study of a group of 6- to 7-year-old schoolchildren is proposed.