advancing education in optometry · the improvement of vs by amblyopia treatment improves...

AdvancingEducationinOptometryScientificPapersSessions

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Improvement of visual sensitivity by amblyopia treatment also improves ocular functions Jae-Do Kim1, Jeong-Sik Son1, Dong-Sik Yu1, Jung Ho Yoon2,3 1Department of Optometry and Vision Science, Kyungwoon University, 2Carl Zeiss Vision Korea, Seoul,3Department of Optometry, Konyang University, Daejeon, Korea Purpose: Amblyopia is an uncorrectable decrease in vision in one or both eyes with no apparent structural abnormality and occurs due to a delay in the development of visual sensitivity. This study is to investigate whether improvement of visual sensitivity (VS) by amblyopia treatment affects ocular functions or not. Methods: 20 subjects (31 eyes) (mean age of 10.7 ± 2.9 years) who treated for amblyopia were enrolled for this study. Refractive errors, accommodative errors, and distance and near phoria were compared for before and after treatments of amblyopia. Refractive errors were measured using open-field auto-refractor (NVision-5001, Shin Nippon, Japan). Accommodative errors at 40 cm were determined using monocular estimated method (MEM). Phoria was determined at 3m for distance and at 40 cm for near using Howell phoria card, cover test or Maddox rod. Results: Mean corrected visual acuity (CVA) significantly increased by 0.46 ± 0.11(decimal notation) for before amblyopia treatment to a level of 1.03 ± 0.13 for after amblyopia treatment (paired t-test, p 0.05). Accommodative error significantly decreased from accommodative lag of +1.1 ± 0.75D to a level of +0.5 ± 0.59D (accommodative lag) (paired t-test: p < 0.05). Distance phoria significantly changed from eso 2.9 ± 6.17PD (prism dioptres) to a level of eso 0.2 ± 3.49 PD (pair t-test: p < 0.05), and near phoria also significantly changed from eso 0.4 ± 2.32PD to level of exo 2 ± 4.9PD (pair t-test: p < 0.05). Discussion: Hyperopic refractive error decreases with improvement of CVA or VS in amblyopia treatment. The improvement of VS by amblyopia treatment improves accommodative response and changes phoria affected accommodation. The effects of stereoscopic 3-dimensional display on visual and physical discomfort Yu-Chi Tai, James Sheedy, James Kundart, Sowjanya Gowrisankaran, Andrew Reder Vision Performance Institute, Pacific University, Oregon, USA Purpose: Accommodation and vergence responses in real world are behaviourally coupled to maintain clarity and singularity for the object of interest. However, stereoscopic three-dimensional (S3D) create non-normal coupling that may cause accommodation-vergence discord and motion-induced visual-vestibular abnormalities and possibly induce discomfort and dizziness. The present study examined the effects of stationary (static) and dynamic (moving in depth) stimuli on reported symptoms of S3D symptomatic and non-symptomatic subjects and correlate with their clinical profile. Methods: Twenty self-reported S3D-symptomatic subjects with previous experiences of visual and/or general physical symptoms in S3D viewing and twenty age/gender-matching subjects without discomfort experience served as control. Visual/physical discomfort response in a 3D gaming task was recorded to confirm the group assignment. Subjects read still S3D text at various amount of disparity and viewed a random-dot motion film in 2D and S3D separately. Stereoacuity and binocular vision was assessed by a clinician blind to the group assignment.

Scientific Papers Session I

2 October 2013 (Wednesday) 11:15 – 12:30

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Stereoacuity is related to academic and visual-motor performance in children with developmental disorders Tomohito Okumura1, Tomoko Miura2, Makoto Nakanishi3, Eiji Wakamiya3, Hiroshi Tamai1,4 1Learning Disability Centre, Osaka Medical College, Takatsuki, 2Palm Children's Clinic, Ritto, 3Graduate School of Psychology, Kansai University, Suita, 4 Department of Paediatrics, Osaka Medical College, Takatsuki, Japan Purpose: Binocular dysfunctions are common problems that can potentially reduce academic and visual-motor performance. Children with developmental disorders, such as learning disability, attention deficit and hyperactivity disorder, pervasive development disorder, could experience more difficulty in academic and visual-motor activities when they are also suffering from visual skills problems including binocular dysfunctions. However, few scientific researchers have conducted to investigate the relationship between binocular dysfunction and academic and visual-motor performance at school in children with developmental disorders. The current study investigated the relationship between stereopsis at near, one of the major parameters of binocular function, and academic and visual-motor performance at school. Methods: 142 1st to 6th grade school-children with developmental disorders between the age 7 and 12 were retrospectively reviewed and separated into two groups; those with low stereoacuity at near (LS) and those with normal binocular vision (NBV). Vision-related symptom checklist for children (VSCL; Okumura, 2013) and near and far number copying test (n/f NCT; Okumura, 2008) were analyzed to investigate academic and visual-motor performance. Results: Compared to NBV group, more symptoms and lower academic and visual-motor performance were found for LS group on VSCL (p

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(2 clinical signs) (23.42%) and definite CI (3 or more clinical signs) (14.42%). The mean CISS scores for the 818 subjects in the study was 12±8.4. The mean NPC was 6.8cms ± 2.2 (break value).The mean near PFV (step vergence with horizontal prism bar) was break 24ΔBO± 10.87 and recovery 20ΔBO±9.69. The mean exophoria was 3Δ ± 2.1. Discussion: The findings suggest that CI (defined as suspect and definite CI) is frequent (37.89%) among 12-16 year old school children and tests for CI should be routinely carried out in this age group to rule out CI. There was a steady increase in prevalence of CI with increasing age and no gender prediction in our study. The performance of questionnaire, stereoacuity and visual acuity test as vision screening tools for children with learning disabilities in primary schools Nurul Farhana Abu Bakar1, Ai Hong Chen2 1Optometry Unit, Hospital Sri Aman, Sri Aman, Sarawak, 2Department of Optometry, Faculty of Health Sciences, Universiti Teknologi MARA Puncak Alam, Selangor, Malaysia Purpose: The purpose of this study was to evaluate the performance of the modified COVD-QOL questionnaire (MCQL), Cambridge Crowding Cards (CCC) and Lang II Stereotest as vision screening tools for children with learning disabilities in government primary schools in Malaysia. Methods: Sixty-five children with learning disabilities were recruited from 6 schools in Kuala Lumpur. Information regarding their visual symptoms was obtained by interviewing their parents or teachers using the MCQL. Then, all children were screened using the CCC and Lang II Stereotest. The performance of the vision tests was evaluated based on the sensitivity and specificity to identify 3 categories of vision disorders: reduce visual acuity, accommodative response anomaly and convergence insufficiency. Results: The proportion of the children who have reduced visual acuity, accommodative response anomaly and convergence insufficiency was 66%, 40% and 9% respectively. The MCQL questionnaire showed high sensitivity (82%) to detect any of the targeted conditions in the first level of screening. The sensitivity and specificity of combined CCC and Lang II Stereotest in the second level of screening was 84% and 100% respectively. Discussion: The new approach of combining a questionnaire and child-friendly vision tests with two levels of screening was found to be adequate as a vision screening approach for children with learning disabilities in schools due to its ability to detect important vision disorders while maintaining simplicity and cost effectiveness.

Scientific Papers Session I

2 October 2013 (Wednesday) 11:15 – 12:30

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A novel insight on clinical applications of pinhole test David Pei-Cheng Lin, Li-Chien Yang, Yu-Shuo Chang, Bo-Yie Chen, Han-Hsin Chang School of Optometry and Core Laboratory of Vision Protection and Biotechnology, Chung Shan Medical University, Taichung, Taiwan Purpose: Many efforts have been endeavoured by optometrists to push the best corrected visual acuity to the maximum. Pinhole test is the most popular method used by optometrists for this purpose and is regarded as one of the easiest methods for retinal health evaluation. Nevertheless, there has been no sufficient information regarding the effects of illumination, optotypes, age, and gender on pinhole measurements. This study aims to clarify the influence of these complication factors and seek the best application for pinhole test. Methods: We recruited 30 volunteers, aged between 20 – 50 years, and measured their visual acuity under light (500 lux) and dark (5 lux) environments, using either black or white optotypes. The results were compared, according to age, gender, optotype, and illumination, for significance using student’s t test or paired-t test. Results: We found that visual acuity can be affected by illumination, optotypes, age, and gender when pinhole tests were applied. Discussion: Appropriate pinhole test conditions should be applied to different patients. Based on our findings, we propose a novel strategy to assess whether the prescribed lenses have helped to achieve best corrected visual acuity. Whole-surface prism distribution in progressive addition lenses Ching-Yao Huang Department of Optometry, Shu Zen Junior College of Medicine and Management, Taiwan Purpose: The prismatic effects (prism) of progressive addition lenses (PALs) have been investigated previously. However, only the PALs with low distance powers ranging from -2.00 D to +2.00 D with a single add power were examined. No systematic comparisons of whole-surface prism in PALs were reported. This study is to evaluate the prism characteristic in PALs with various distances and add powers. Methods: A Hartmann wavefront aberrometer was used to measure the whole-surface prism distribution in PALs with five distance powers (-5.00 D, -2.00 D, 0.00 D, +2.00 D, and +5.00 D) and five add powers (+1.00 D, +1.50 D, +2.00 D, +2.50 D, and +3.00 D) in each distance power. All PALs were lenses made of plastic materials with refractive index 1.60 and had similar progressive corridor length for comparison. The contour plots of prism in 40-mm diameter were generated with custom MATLAB programs. Results: The results show that the prism distribution is apparently different among the PALs with different distance powers and varies with adds powers in PALs with the same distance power. The prism at distance area in PALs with the same distance power looks similar, but tends to increase at progressive corridor and near areas in PALs with positive distance powers and to decrease in PALs with negative distance powers. The measured prism data are also in agreement with the theoretical calculation based on the Prentice’s rule for all PALs. Discussion: The importance of the results demonstrates that prismatic effects of PALs depend on the total power contribution of distance and add powers as well as the distance away from the prism reference point.

Scientific Papers Session II

2 October 2013 (Wednesday) 14:30 - 15:30

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One limitation could be the fact that lenses were evaluated laterally (no rotation and no tilt), which would less accurately represent the prism compared that as worn by the patient. Dynamic contour tonometry over contact lens Andrew KC Lam, Jimmy Tse School of Optometry, The Hong Kong Polytechnic University, Hong Kong Purpose: Dynamic contour tonometry (DCT) is less affected by corneal characteristics. However, DCT requires topical anaesthesia. This study explored the feasibility of performing DCT over silicone hydrogel contact lenses. Methods: Forty-seven young adults had DCT performed over two types of silicone hydrogel contact lenses, with different lens moduli. Each eye wore one type followed by another, randomly assigned, and then the lenses switched over. Conventional DCT was performed finally. Difference and agreement of DCT results with and without silicone hydrogel contact lens were studied. Results: Both eyes had similar corneal curvatures and central corneal thicknesses. There was a greater IOP difference (agreement: 2.73 mmHg) compared with no lens when it was measured over high modulus silicone hydrogel lenses. Agreement improved over silicone hydrogel lenses of low lens modulus (agreement: 2.2 to 2.4 mmHg). Agreement was within 1.0 mmHg for ocular pulse amplitude. Conclusions: With no topical anaesthesia, DCT can be performed with reasonable clinical acceptance. However, patients are not advised to be wearing silicone hydrogel lens of high lens modulus. Diagnosis and management of normal tension glaucoma: the next generation Mark Eltis School of Optometry and Vision Science, University of Waterloo, Waterloo, Canada Presenting Signs and Symptoms: A 68-year-old woman presented to our office for a routine exam. She was not taking any medication and had no history of health problems either in general or specifically of the eye. Investigations: Subjective refraction was OD +2.25 -2.00 X 061 20/25 and OS +3.25 – 2.00 X 120 20/20 with a +2.50 add OU. Intraocular pressure was 16 mmHg in both eyes at 3:30 p.m. using Perkins applanation tonometry. Cup-to-disc ratios were 0.8/0.8 OD and 0.7/0.7 OS. Gonioscopy (Goldmann) was performed and did not reveal any pathology. Scleral spur was identified in all four quadrants of both eyes. Central corneal thickness was measured to be 510 microns OD and 515 microns OS. Visual field testing showed a large inferior arcuate defect OU which corresponded to the NFL superior defect on both the OCT and HRT. The visual field test was very reliable and GHT was outside normal limits in both eyes. The damage was bilateral and consistent with glaucomatous loss.



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Case Management Plan: Following an evaluation by a glaucoma specialist, Travatan Z: 1 drop once per day OU was prescribed. At follow up, the patient’s IOP was noted as 12 mmHg in both eyes at 3pm and an appointment was scheduled for 6 months. The patient was subsequently lost to follow up. Discussion: The definition, diagnosis and management of glaucoma have changed radically over the last decade. This presentation reviews recent advances in glaucoma and how they were applied to the case of a 68-year-old patient. This case highlights the importance of non-IOP‒related factors and the application of modern technology and therapy in the management of this disease.



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Simple way to measure a change in refraction at night Mitsuhisa Hayashi1, Taeko Horino2, Yuichiro Kanazawa2, Yoshihiro Ozaki2, Hiroshisa Terabe2 1Tokyo Optometric College, Tokyo, 2Product Development, Optometry R&D Department, Nidek Co. Ltd., Aichi, Japan Purpose: There are people who experience difficulty in seeing at night or dusk. The phenomenon is called night myopia, and has been studied for many years. Recently, a new visual acuity chart SSC-350CG type L has been developed from Nidek Co. Ltd. It has two sets of chart brightness; the normal daylight level (180 cd/m2) and the night level (10 cd/m2). Using this chart, the change in refraction between day and night, and the visibility is studied. Methods: 127 subjects (240 eyes)(aged 24 to 59 years) are screened with Auto Corneal Topographer and Refractor, OPD-Scan III (Nidek) to find those who have a large difference in objective refraction through 4 mm and 6 mm pupil area. The cases, where there are differences in sphere power over ±0.50, or in cylinder power over ±0.50, or change in cylinder axis over 10 degrees where there is more than 0.25 dioptres of cylinder power, are screened out and received a subjective refraction with SSC-350CG type L, and see if there is subjective difference in vision. Results: 56 out of 240 eyes are screened objectively and 23 out of 56 subjects have experienced the better vision through the refractive data under the low illumination. The Log MAR visual acuity with correction for normal light level with low illumination chart is 0.10 ± 0.14, and that for low illumination level is 0.03 ± 0.11. There is statistically significant difference. (p

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beam without participant’s fixation, 3.92mm for low beam with participant’s fixation and 4.38mm for low beam without participant’s fixation on the headlight. Discussion: Pupil size dynamics varied substantially according to different road lighting and in response to the headlight beams of on-coming vehicle at night-time. These differences in pupil size will potentially impact on the visual performance for patients who wear multifocal contact lenses, intraocular lenses, orthokeratology and those post-surgery following refractive surgery. Vision, optical correction and night driving performance Michael Collins School of Optometry & Vision Science, Queensland University of Technology, Brisbane, Australia Purpose: To investigate the effect of different levels of refractive blur on driving performance measured under day and night-time conditions. Methods: Participants included 12 young adults (mean age=25.6 ± 5.2 years) with normal vision who drove a research vehicle around a 4 km closed road circuit with 3 different levels of binocular spherical refractive blur (0.00 DS, +0.50 DS, +1.00 DS, +2.00 DS). The subjects wore optimal sphero-cylinder correction for the control condition and the order of testing of the blur conditions was randomized. Driving performance was assessed in two different sessions under day and night-time conditions and measured road signs recognized, hazard detection and avoidance, gap detection, lane-keeping, sign recognition distance, speed, and time to complete the course. Results: Both blur and time of day had significant effects on driving performance (p

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Dry eye in patients with contact lens microbial keratitis Lili Asma Ismail1, Azrin Esmady Ariffin1, Karunakar, TVN2, Mohd. Hafidz Ithnin3 1Faculty of Optometry and Vision Sciences, SEGi University, Petaling Jaya, 2Department of Ophthalmology, Hospital Kuala Lumpur, 3Kulliyah of Allied Health Sciences, International Islamic Universiti Malaysia, Kuantan, Malaysia Purpose: To investigate the quality and quantity of tears in patients with previous episodes of contact lens microbial keratitis (CLMK). Contact lens microbial keratitis is a complication of contact lens wear. Dry eye is an abnormality of the tear film and has been associated with CLMK in previous studies. Methods: This is a cross sectional study conducted in an eye care facility from June 2012 until December 2012. Two groups were recruited for the study. Cases recruited were patients who had previous histories of CLMK of at least 6 months from date of recruitment and have since discontinued lens use. The second group were controls which comprised non-contact lens wearers. Both groups had no other anterior segment or systemic disease. Subjects were required to answer questionnaires on demographic, medical history and Ocular Surface Disease Index (OSDI). Clinical examination which included slit lamp, tear ferning, fluorescein tear breakup time (FTBUT), Schirmer’s test 1 and Schirmer’s test with anaesthetic was done. Results: There were 14 subjects in the case group and 16 subjects in the control group. Subjects did not differ significantly in age (p=0.084). The OSDI scores were statistically significant between groups (ҳ2=35.97, df=3, p

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resolved and she was instructed never to sleep in her contact lenses and informed of the risks of noncompliance. Discussion: CLMK is a potentially blinding complication most often involving overnight contact lens wear. This case report reviews the management of a patient with CLMK and discusses the aetiology, differential diagnosis and risk factors associated with the condition. This case demonstrated how rapid diagnosis and effective management in the initial stages of the condition resulted in quick resolution and prevented vision loss. The influence of pupil size and decentration of simultaneous vision multifocal contact lenses on visual acuity Jungmi Kim, Kichoong Mah Department of Health Science, Graduate School of Eulji University, Daejeon, Korea Purpose: To evaluate the influence of different factors - based pupil size (mm), decentration (mm) and three different add powers of a multifocal contact lens (CLs) on visual performance. Methods: 53 presbyopic patients were evaluated using multifocal CLs (Air Optix multifocal, CIBA Vision) with low, medium and high additions. After one month of daily wear, high contrast distance visual acuity was measured with the PVVAT™ (Precision-Vision, USA). Near visual acuity and stereoacuity were measured by ETDRS chart (New EDTRS 2000, Precision-Vision, USA) and Titmus (The Vision Assessment Corporation Fly Stereo Acuity Test with Lea Symbol P/N 1000) respectively, under approximately 85cd/m2 luminance setting at 40cm. Photopic and mesopic pupil size and decentration of multifocal CLs were measured with the OPD- SCAN II (NIDEK Co.). Subjective satisfaction was assessed and measured by questionnaire. Results: The respective photopic and mesopic pupil size (mm) were 4.45±0.56 and 6.02±0.68. Binocular corrected visual acuity (logMAR) was 0.05±0.05 and 0.15±0.05 for high and low contrast distance VA, 0.17±0.08 and 0.26±0.08 for high and low contrast near VA respectively. The mean of near steroacuity (sec of arc) was 52.03±42.70. There was a statistically significant correlation between photopic pupil size and high contrast near VA(r=0.26, p=0.04). The mean of decentration (mm) was 0.42±0.15mm. High add was rated significantly lower for satisfaction of near vision, near stereoacuity and symptom of halo and glare than for low and medium add, but no significant difference in subjective satisfaction related to distance and intermediate vision was observed. Conclusions: The pupil size and decentration plays an important role in centre-near design of multifocal CLs. Pupil size was found to be significantly correlated with near visual acuity. The low and medium adds of the multifocal CLs used in this study produced better optical performance than did the high add under real life conditions. As a result of our findings, simultaneous vision multifocal contact lenses can be considered a good option to correct both distance and near vision while preserving stereopsis.

Scientific Papers Session IV

3 October 2013 (Thursday) 11:30 - 12:30

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AFM and SEM analysis of limbal ring contact lenses Michael Mayers, Katherine Osborn Lorenz, Joseph Kakkassery Johnson & Johnson Vision Care Inc., Jacksonville, FL, USA Purpose: Limbal Ring (also known as “circle-tinted”) contact lenses have received negative press in the past few years. All limbal ring lenses, however, are not the same. The pigment particles can be found on the front or back surface of the contact lens or ‘enclosed’ within the lens matrix, which may lead to differences in on-eye performance. The purpose of this study was to evaluate the pigment location and surface roughness of ‘circle’ contact lenses from seven manufacturers. Methods: Scanning Electron Microscopy (SEM) was completed by an ISO-certified laboratory to discern the placement of pigment, whether on top of or enclosed within the contact lens material, to a sub-micron level. Atomic Force Microscopy (AFM) was used to measure the surface roughness of both pigmented and non-pigmented regions of the front surface and back surface of the contact lenses. Results: SEM cross-section images at 500x and 2,000x magnification showed pigment on the surface of 6 of the 7 lens types tested. The mean depth of pigment for 1-DAY ACUVUE DEFINE (1DAD) (JJVCI) lenses was 8.1 um below the front surface of the lens, while the remaining lens types tested had pigment particles on the front surface or back surface of the lens. Results of AFM analysis indicated that 1DAD lenses had lower RMS roughness values than the other lens types tested (1DAD RMS roughness pigmented area mean = 6 um vs 35-61 um). Conclusion: SEM and AFM testing revealed pigment on the surface of the lens for all types tested with the exception of 1DAD. Further research is required to determine if the difference in pigment location influences on-eye performance.

Scientific Papers Session IV


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Orthokeratology and myopia control: a long term study for effectiveness with different corneal conditions and design formats Edward Chow Private practice, Toronto, Canada Purpose: Although orthokeratology has been proven to be an effective mean of myopia control in young children, recent publications only report a 50% reduction. The present study allows us to determine a lens design format to achieve better results based on the peripheral defocus theory. This is important to provide a better understanding of the mechanisms underlying the higher failure rate. Methods: Under a 12 years study period, 500 children in both genders from age 10 to 14 go through the evaluation wearing night-wear OrthK lenses. Variables such as initial Rx, corneal curvature, eccentricity value, pupil size and central corneal thickness are identified & evaluated for different design options to achieve results. Axial lengths are measured pre-treatment and in 6 months interval as an indication to assess the myopia control results. Control group results are compared. Results: A higher percentage of myopia control can be achieved using the more effective design. As high as a 90% reduction rate is secured, adverse corneal conditions are identified for fitting options. Discussion: Most of the traditional designs are not as effective especially for low myopia & specific corneal conditions that fail to observe the defocus theory. Various new concepts that are capable to generate the proper forces to satisfy the theory can be employed for results. This study also serves to identify the various adverse corneal conditions. By applying the proper design, these can be overcome. Lens design formats will be discussed and illustrated with tear film diagrams. Advanced orthokeratology: how toric and high myopia work Bruce T. Williams Seattle Vision Care Centre, Inc., Seattle, WA, USA Background: A review of the theory and practice of fitting patients with specialty reverse geometry overnight orthokeratology lenses which have refractive powers of over -1.50 dioptres of astigmatism and myopia of over -6.00 dioptres. Case study: The presentation includes before and after topographies, standard design lenses, computer assisted designs and commercially available specialty designs. Case Management: Strategies on management of high myopia and astigmatism with orthokeratology will be discussed.

Scientific Papers Session V


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Orthokeratology on 11 year old girl with systemic Scleroderma Set Fee Leong, Bridgette Yeoh Y K Leong Optometry Ctr, Petaling Jaya, Malaysia Presenting Signs and Symptoms: 11 year old girl with the condition of scleroderma presented for orthokeratology treatment. She was under regular care by her doctor and now on weekly medication (immunesuppresant) for her condition (off steroids past 3 years). Investigations: Her refractive error was: OD -3.75DS OS -3.50DS; normal range corneal curvature along the flattest meridian OD 7.55 OS 7.50; tangential and axial topomap normal; biomicroscopy showed no abnormalities on the cornea, conjunctiva and eye adnexa. Her eyelids stretched with palpebral aperture R 8.75mm L 9.0mm but she has no problems with lens insertion and removal digitally. Tear characteristics were within the Asian norms for TBUT 6.6+/-2.5s and McMonnies Dry Eye Survey score was 15. Case Management Plan: She was fitted with orthoK lenses (Hiline, Boston XO). Care and maintenance with Boston range of solutions. VA outcomes were good, 6/6 in both eyes within a week. Biomicroscopy on cornea, conjunctiva and eye adnexa revealed no abnormalities; there was no change in tear characteristics; subtractive tangential topomap revealed good central bullseye. Discussion: Two studies by the Scleroderma Care Foundation reported that patients with Scleroderma may not exhibit increased corneal thickness and short-term effects of overnight orthokeratology on corneal cell morphology and corneal thickness (Nieto-Bona et al 2011). Their findings suggested that the corneal epithelium is the principal structure affected by the mechanical forces exerted by the orthoK lenses. Her central corneal thickness is within norm. For the past 23 months since getting on the orthoK programme, there have been no incidences that required further referral. She is seen on a 3 to 6 months follow up basis. She is very happy to have the freedom from daytime spectacles wear and myopia control. The girl has good family support and motivation for this orthoK programme, thus her compliance was good. Posterior corneal shape changes with overnight corneal edema and physical model of corneal shape change in myopic overnight orthokeratology lens wear Jeong Ho Yoon1,2, Jae-Do, Kim3, HA Swarbrick4 1Carl Zeiss Vision Korea, Seoul, 2Department of Optometry, Konyang University, Daejeon, 3School of Optometry, Kyungwoon University, Kyunbuk, 4School of Optometry and Vision Science, University of New South Wales, Sydney, Australia Purpose: To evaluate the influence of overnight corneal edema on posterior corneal shape during sleep, and conventional and orthokeratology (OK) rigid gas-permeable (RGP) lens wear; to develop a physical model of anterior and posterior corneal changes in overnight OK. Methods: Eighteen adult subjects (19-32 yrs) with low myopia (

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and within 1 hour of eye opening and in the evening (8 ~ 10 hours after lens removal). Repeated measures ANOVA with planned comparisons were used to compare changes from baseline, with a critical p-value of 0.05. Results: In the conventional RGP lens-wearing eyes, there was significant flattening of posterior Ro (p=0.001) and significant increases (towards oblate) in posterior Q (p=0.001) after overnight lens wear. In the OK lens-wearing eyes, myopia reduced from -2.65 ± 0.96D (mean ± SD) to -0.04 ± 0.38D over 14 days of overnight OK. There was significant steepening of posterior Ro in the morning on days 7 and 14 (p

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Role of optometry educators in developing human resources and establishing low vision care services in India Prema K Chande1, Rajesh Kapse2, Sabitra Kundu2 1Lotus College of Optometry, Lotus Eye Hospital, Mumbai, 2Sightsavers, India Purpose: Lack of adequate low vision (LV) services in India has always been a public health issue, 50% of children in schools for the blind, have LV and are trained in Braille and further rehabilitated as blind individuals. The reasons for lack of services were due to lack of skill among eye care practitioners. Situation analysis of infrastructure in optometry schools revealed, that there were no LV clinics in almost 50% of the schools of optometry. Hence a project was developed to incorporate LV training in optometry schools and implemented to develop (and sustain) LV services in India. Methods: Optometry educators were identified for training of LV competencies to undergraduates in their schools. A program with theory and hands on evaluation of LV patients was developed and delivered. A primary LV kit was designed and distributed to various optometry schools. In turn, the optometry educators had to commit that with the given kit, they had to evaluate patients with low vision with the help of their students and send a monthly report on the same. By doing this, they would render services as well as develop human resources for rendering further services. Results: Two such training programs have been held so far and about 32 optometry educators across India have been trained in LV. 20 primary LV clinics have been established in optometry schools to date. Over 150 patients have been examined and 200 optometry students have been trained by these educators in LV care to date. Conclusions: Optometry schools and educators can play a vital role in public health, by not only developing human resources, but also by rendering services. Educators can make sure that besides theory, students' competencies are also well developed which shall lead to better facilities for people seeking services. A survey of intervention programme among visually-impaired students enrolled in Philippine National School for the Blind (PNSB): impact to quality of life Christine S. Rodriguez, Kleidi Dl. Verdote College of Optometry, Manila Central University, Philippines Purpose: The study aims to determine the most effective intervention program for the visually impaired (VI) students enabling them attain fullest potential in life. It sought the demographic profile of respondents from the Philippine National School for the Blind and type of visual impairment. Methods: A survey among 50 VI students enrolled in PNSB was conducted to evaluate the effectiveness of the intervention given and its impact to their quality of life. The null hypothesis is that there is no significant effect of the low vision intervention and services to the quality of life of visually impaired students. Results: The study revealed the following: 1. Respondents were 6-23 years old, 54% in grade school, 42% in high school and 2% in pre-school; 2. Male respondents comprise 56% and female, 44%; 3. 64% of students have low vision, while 36% are totally blind; 4. Braille is predominantly used for reading and writing, less than 10% use low vision optical aids such as magnifiers and telescopes; 5.The following were widely utilized: Braille, mobility cane, talking devices, large-printed materials and electronic devices; 6.The devices and services were rated excellent, as they are used independently and conveniently; 7. Interventions were

Scientific Papers Session VI


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rated effective as they address specific needs, as Braille and cane to totally blind and low vision aids to those with residual vision; 8. Visual impairment has major impact on quality of life, activities of daily living were managed with the help of LVA and services which restored their independence and confidence. Discussion: Majority of the students considered the devices and services as contributory factors for enhancing their quality of life. They were able to pursue their studies and gain hope that they will continue to be productive members of the community, as they search for their perfect place in the mainstream of the social spectrum. Use and efficacy of modified flashing technique in treating patients with nystagmus, cortical visual impairment and delayed visual maturation Aditya Goyal1, Sunita Agarwal2, Ravindra Pandey3 1Sankara College of Optometry, Sankara Eye Hospital, Bangalore, 2Child Development Centre, Apollo Gleneagles Hospitals, Kolkata, 3Vision Therapy Centre, Vision Aid, Chennai, India Purpose: No specific treatment guidelines are available for treating patients with nystagmus. Often, prisms are being incorporated to attain null point. This however does not dampen nystagmus completely and permanently. Traditionally serial lights are being used to stimulate visual process in cortical visual impairment (CVI) and delayed visual maturation (DVM). This is a retrospective study to analyze the use and efficacy of treating patients suffering from the above disorders with a unique modified flashing technique developed for this purpose. Methods: Flash light was modified to provide flashes of variable intensities and also provide single and multiple flashes with variable latencies. 46 children (average age being 5.5 years) suffering from nystagmus, CVI or DVM were treated with this flash using a specific technique for a period ranging from 2 months to 8 months. Of these 19 had nystagmus and the rest had either CVI or DVM. Results: Of the 19 children with nystagmus, it was dampened completely in 15 and was considerably reduced in amplitude and frequency in the rest. Further, the visual acuity also improved in these cases. In children with CVI/DVM, all the children attained functional vision which included form sense, colour recognition, pattern recognition, eye hand coordination, face recognition at variable distances. Discussion: The flashing technique using the modified flash light has shown great promise in treating patients with nystagmus, CVI and DVM. The recovery has been constant and much faster than traditional methods which are being used at present. There have been no deleterious or side effects of this technique. We have been provided with highly positive feedbacks about the outcomes of this procedure by the parents of the children who are being treated. Further studies incorporating electro physiological and other objective methods are being undertaken to establish the efficacy of this technique objectively. Measurement of needed dioptre for near low vision aids with telescope Tadaaki Tanabe1, Hiroshi Uozato2 1Nippon Optometrical College, Osaka, 2Graduate School of Medical Science, Kitasato University, Kanagawa, Japan Purpose: Equivalent viewing power (EVP) of the adjustable focus telescope for near vision varies according to the length of the telescope. If a person with low vision can read the target letters through the telescope,



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the EVP of the telescope should indicate the proper dioptre for a near low vision aid. We investigate the dioptre measured with the telescope, compared with a dioptre which was calculated using the reading chart. Methods: To measure the EVP with the telescope, we put the calibration of the dioptre and the working space on the tube of the telescope and the optical bench. The target letters which denoted 1.0M in the MNREADJ reading chart and the telescope were set on the optical bench. Six normal sighted subjects simulated low vision. The dioptre calculated in relation to the critical size of the MNRADJ was compared with the dioptre measured with the telescope. Results: The mean corrected visual acuity for distance vision of 6 subjects was logMAR -0.09±0.07. When they simulated low vision, the mean visual acuity for distance vision reduced to logMAR 0.47±0.16, and the mean visual acuity for near vision was logMAR 0.54±0.12. The mean critical size of MNREADJ was logMAR 0.68±0.04, which could be converted to 6.4±0.5D of the dioptre that was needed for near low vision aid. The mean needed dioptre for near low vision aids measured with the telescope was 7.0±0.8D. There was no significant difference between MNREADJ and the telescope to estimate the needed dioptre for near low vision aids. Discussion: The measurement with the telescope was as useful as MNREADJ. The needed dioptre for near low vision aids was easily estimated with the calibration using the adjustable focus telescope for near vision without requiring any calculations using MNREADJ. A comparison between different age groups for the follow up of low vision rehabilitation in Mumbai Yogita L Rajgandhi Premila Vithaldas Polytechnic-SNDT University, Mumbai, India Purpose: To evaluate the importance of follow up for low vision rehabilitation in specific age groups in Mumbai. Methods: The data was collected from different primary and secondary eye care centres. The retrospective studies were analyzed from data of 94 patients recorded from M.N.B.I. Home for the blind Mumbai. The data collected included age, gender, requirement of low vision devices, various rehabilitation approach, and acceptance of loss of sight, vocational training, and visual rehabilitation. The data was then segregated into 3 groups of paediatric, adult and geriatric age group. Adult age group was the highest potential for low vision rehabilitation follow-up followed by paediatric group. Results: The total number of visually impaired patients analyzed was 94. Adult (Age 17-45 yrs) 72% were highly motivated, self-decision making, great confidence, well acceptance of loss of sight and understanding the outcome of rehabilitation were the reason to be follow up regularly than paediatric (3-16 yrs) 17% and geriatric (55-82 yrs) 11% . Paediatrics were dependent on parents and family to take further follow up and geriatrics had lower interest in daily activity, psycho-social factors were responsible for poor follow up. Conclusion: Paediatric age group was poor in follow up although they were the best candidates for rehabilitation. Education is required for follow up of low vision rehabilitation. If all the centres in Mumbai had a multidisciplinary approach then follow up would have been much stronger.



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Validity of teacher-based vision screening and factors associated with the accuracy of vision screening in Vietnamese children Prakash Paudel1, Vilas Kovai1, Thomas Naduvilath1, Ha Thanh Phuong1, Suit May Ho1, Nguyen Viet Giap2 1Brien Holden Vision Institute, Sydney, Australia, 2Ba Ria-Vung Tau Provincial Eye Centre, BRVT Province, Vietnam Purpose: To assess the validity of teacher-based vision screening and factors associated with the accuracy of vision screening in Vietnamese children. Methods: After brief training by an optometrist and an ophthalmologist, teachers independently measured visual acuity in 555 children aged 12 to 15 years in Ba Ria–Vung Tau province. Visual acuity measurements by teachers were compared to those measured by experienced refractionists. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) with 95% confidence intervals were calculated for uncorrected visual acuity (UVA) and presenting visual acuity (PVA) of 20/40 or worse in either eye. Chi-square, Fisher’s exact test and multivariate logistic regression were used to assess factors associated with the accuracy of vision screening. Level of significance was set at 5%. Results: Trained teachers in Vietnam demonstrated 86.7% sensitivity, 95.7% specificity, 86.7% PPV and 95.7% NPV in identifying children with vision impairment using the UVA measures. When screening was based on PVA, teachers demonstrated relatively low accuracy (75.3% sensitivity, 93.0% specificity, 69.5% PPV and 94.7% NPV) and this was significantly associated with child’s age, gender, spectacle wear and myopic status. However, none of the factors was associated with the UVA measurement accuracy. Conclusions: School teachers in Vietnam achieved better accuracy in the measurement of visual acuity and identification of children with vision impairment using UVA measures compared to PVA. The UVA measure is thus recommended for a teacher-based vision screening program.



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The use of rigid gas permeable contact lens in the management of congenital nystagmus – case report Lian Buck Koh Private Practitioner, Singapore Case History: A 33 years old female Caucasian presents with congenital idiopathic nystagmus. She has no other systemic condition and was an adapted soft toric contact lens wearer. She was referred to my practice for refitting of contact lenses as she had been complaining of fluctuating vision. The fluctuation in vision was due to the rotation of the toric lens, thereby causing off axis astigmatic blur. The nystagmus is also compounding the problem. Management Plan: She was refitted with RGP lenses (Boston EO) after a thorough discussion. Although she experienced the usual discomfort, the one week post fit review was particularly encouraging. While her visual acuity improved by only 1 line to 6/7.5 in each eye, her functional visual acuity has gained considerably. She did not complain of any fluctuating vision and was able to drive with confidence. Lens discomfort had become more bearable and she was able to wear the lenses for 12 hours a day every day. Discussion: By the fourth week, the patient had fully adapted to the RGP lens. Not only herself, but her husband commented that her eyes no longer move as much as before. She also expressed that her self-confidence and esteem has become much higher. Although our objective findings showed slight improvement in her measured visual acuity, the emotional and psychological joy shown by the patient supports the notion suggested by previous investigators that contact lens is a valid choice of correction for nystagmoid patients. The oscillations of the eyes do not appear to cause any more discomfort than normal eyes when fitted with RGP lenses. In fact the sensory feedback of the lens on lids may result in lesser oscillations of the eyes. Comparison of various contact lenses for visual rehabilitation of keratoconus and irregular cornea Mohammed Kazi, Jatin Ashar L V Prasad Eye Institute, Mumbai Eye Care, Cornea and LASIK Centre, India Purpose: To evaluate and compare the various types of contact lenses (RGP, Rose K2, Rose K NC, Rose K PG, Rose K IC, Kerasoft, Clearkone hybrid lenses, semi scleral and scleral contact lenses) in terms of their ease of fitting, number of trial lenses, visual outcome and fitting parameters. Methods: Retrospective analysis of patients presenting to the contact lens clinic of a single centre from January to June 2013. Patients with irregular cornea due to keratoconus, pellucid marginal degeneration, post corneal transplant, ocular surface disorders were fitted with contact lenses such as RGP, Rose K (Rose K 2, Rose K NC, Rose K PG, Rose K IC) hybrid, semi sclera or scleral based on the corneal topographic features, indications and/ or patient comfort. Number of trial lenses needed for the final fit, BCVA with final fit and patient comfort were analyzed. Results: 9 eyes were fitted with RGP lenses, 22 were fitted with Rose K 2, 5 were fitted with Rose K NC, 9 with Rose K PG, 2 with Rose K IC, Kerasoft lenses in 2, Hybrid contact lenses in 7, miniscleral in 6, 12 with sclera contact lenses. Final fit for Rose K lenses was achieved in mean 3 trial lenses, for RGP lenses mean 5 trail lenses were required to achieve the final fit. Kerasoft lenses were fitted in 4 trial lens, miniscleral and sclera lenses were fitted in mean 4 trial lenses. Hybrid lens final fit was achieved in 3 trial lenses. Patient comfort was highest for Rose K2, Rose K NC and hybrid lenses. Time required learning insertion was shortest with hybrid, mini – scleral and sclera contact lenses.

Scientific Papers Session VII

4 October 2013 (Friday) 09:45 – 10:30

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Conclusion: Rose K and hybrid lenses provide better fitting in cases with corneal irregularity in fewer trials with good visual improvement. Scleral lens and Kerasoft though providing good visual outcomes needed multiple trial lenses to be used and longer chair time. Common symptoms of Nepalese soft contact lens wearers: a pilot study Kishor Sapkota1, Madalena Lira1, Raul Martin2, Sandra Franco1 1School of Science, Department of Physics, University of Minho, Portugal, 2IOBA Institute, University of Valladolid, Spain Purpose: Many patients discontinue contact lens (CL) wear due to different level of symptoms. No study has been done about the symptoms in Nepalese soft CL wearers. The aim of this study was to determine the common symptoms found in current soft CL wearers among Nepalese population. Methods: Two hundred and three current CL users who started to wear soft CL from Nepal Eye Hospital from July 2006 to June 2011 were asked to participate in this study and 129 participated. Frequency of ten common symptoms; which were divided into never, occasionally, frequently, consistent; and scored 0, 1, 2, 3 respectively, were determined. Subjects were classified into asymptomatic, mild, moderate or severe symptomatic depending upon the symptom score. Association between symptoms with other factors, e.g. age, gender, profession of the subjects were analyzed. Results: 96.9% of the subjects had at least one symptom during their CL wearing period. Discomfort was found in 88.4% of the total subjects. Other common symptoms found were foreign body sensation in 73.6%, redness in 65.9%, and reduced wearing time in 63.6% and dryness in 62.8% of the subjects. Majority of the symptoms were found occasionally in the subjects. One quarter (26%) of the subjects were asymptomatic while more than half (57%) were mild symptomatic. Symptoms were positively associated with passive cigarette smoking but not with age, gender, profession and duration of CL wear. Discussion: Almost all the Nepalese soft CL wearers had some types of symptoms. Discomfort was the most common symptom. Patients have been still wearing CL because most of the symptoms were occurred only occasionally. Symptoms may be reduced by the proper selection of lens material, design, care system which might help to reduce the lens discontinuation rate in Nepalese soft CL wearers.

Scientific Papers Session VII

4 October 2013 (Friday) 09:45 – 10:30

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Prescribing eye protection and refractive correction Stephen Dain Optics and Radiometry Laboratory, Australia Review: Optometrists are well versed in the selection of frames and lenses for optimal refractive correction. Increasingly there is a demand for prescription occupational eye protection. In occupational health and safety, the first priority is eye protection and this must drive the choice of lenses and frames. The options for providing both occupational eye protection and refractive correction will be reviewed. In particular, the selection of appropriate ophthalmic lens materials will be highlighted. Sharing of cases on the usefulness of spectral domain Optical Coherence Tomography (OCT) in optometric practice Liang-Hwee Koh Pearl's Optical Co. Pte Ltd, Singapore Purpose: Sharing of cases to show the usefulness of the spectral domain OCT in an optometric practice in Singapore. Methods: Spectral domain OCT has the following functions: (1) Non mydriatic retinal camera, (2) Retinal nerve fibre layer analysis, (3) A scan of the retinal, (4) Corneal thickness map, (5) Anterior chamber angles measurement, (6) Corneal curvature measurement. The non mydriatic retinal camera of the OCT was used on all patients that came to the optometric practice for optical aids. From the retinal images and/or at the end of a full eye examination if ocular pathologies were suspected, the OCT functions were used. Case presentation: The use of the OCT had helped the practice to pick up many cases of both anterior and posterior ocular pathologies. Interesting cases will be presented. Conclusion: OCT is the most useful piece of ophthalmic instrument for an optometric practice. It reduces eye examination time and extremely sensitive in picking up ocular pathologies. Clinical features of adenoviral keratoconjunctivitis – case report Jason Kimberly Specsavers, Australia Presenting Signs and Symptoms: A 20 year old girl presented to a practice with complaints of red eyes, pain, discomfort, watery discharge and a little photophobia on both eyes. She visited two years ago for monthly toric Si-Hy contact lenses fitting and came back 12 months later for regular check-up, then presented sectoral conjunctival redness on temporal right eye for 9 weeks ago. Objective Measurements: Her visual acuity was 6/5 for each eye. Anterior chamber and lenses were normal. All her posterior eyes seemed no abnormal detected. With fluorescein, corneal subepithelial infiltrates were observed, while no palpebral follicles found.

Scientific Papers Session VIII

4 October 2013 (Friday) 11:30 – 13:00

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Diagnosis: The patient presented with the typical signs and symptoms of keratoconjunctivitis from adenovirus (EKC). She had caught a cold a week ago and was observed with watery discharge, scattered nummular subepithelial corneal opacities. Microbial Keratitis, infected from bacteria, viruses may have large corneal infiltrates and PEDAL mnemomic (pain, epithelial defect, discharge, anterior chamber reaction and central location). Herpes simplex keratitis usually leads to corneal oedema, keratic precipitates, and dendritic ulcer. Typical symptoms of allergic conjunctivitis are itchiness and chemosis. Episcleritis (especially diffused form) shows dilated episcleral vessels, no discharges. Subconjunctival haemorrhage usually occurs in one eye with no discharge and clear ring around the limbus. Management Plan: Due to its highly contagious nature she was advised not to go to her school and discard contact lenses and cases. Lubricant eye drops for improving ocular comfort, cold compress and irrigation may be helpful. No antiviral agents are effective, while follow-up in 7-10 days is enough for checking any scarring on the cornea or conjunctiva. Discussion: Most red eyes would have self-limiting, while a few would have severe consequences to eyes. Proper questioning, systemic order of procedures and consultation room hygiene are very important as well as appropriate management plan.

The effect of accommodation and vergence functions to myopia progression Gyeongae Han, Kichoong Mah Department of Health Science, Graduate School of Eulji University, Daejeon, Korea Purpose: This study assessed the accommodation and vergence functions in children to predict the refractive error or the progression of myopia. Methods: 136 Healthy children (mean 10.33±2.24 yrs) were measured in subjective refraction and they were divided into emmetropia (57 counts) and myopia (33 counts) groups, and were observed over a 1 year period. Subjective refraction was performed, and accommodation and vergence functions were measured using an open-field autorefractor (NVision-K 5001, Shin-Nippon) and a modified Thorington phoria, the Bernell Muscle Imbalance Measure (MIM), test card at baseline and 1 year later. Results: Compared with emmetropes, PRA and accommodative response of myopes were lower, but the response AC/A ratio of myopes were higher and near phoria of myopes was more esophoric. Accommodative response of children with esophoria at near was lower than those with exophoria, and the response AC/A ratio of children with esophoria at near was higher than with exophoria. 0.37D or more myopic shift in refractive error during the 1 year follow-up period (mean -0.62±0.20D) was found in 57% of subjects. The response AC/A ratio has the highest correlation with myopia progression and 26.4% of emmetropes became myopic during the 1 year follow-up period, the response AC/A ratio has the highest correlation with the onset of myopia. The relative risk for the onset of myopia in emmetropes within 1 year with a response AC/A ratio of 7.42Δ/D or more was elevated.

Scientific Papers Session VIII

4 October 2013 (Friday) 11:30 – 13:00

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Conclusions: Response AC/A ratio were significantly correlated with change in refractive error in both myopes and emmetropes. An elevated response AC/A ratio in emmetropes were the important risk factor of myopia onset. Accordingly, it is considered that the response AC/A ratio should be assessed to predict myopia progression and onset of myopia in school-aged children for the best prescription and care of myopia. Accommodative responses in Down’s syndrome subjects using the WAM5500 binocular open field auto-refractometer Fakhruddin S. Barodawala, Trupti R. Khaladkar, Neepa Thacker Dave Lotus College of Optometry, Mumbai, India Purpose: Many studies have shown that subjects having Down’s syndrome exhibit high accommodative lag. This research was conducted to study the accommodative responses in subjects with Down’s syndrome using the WAM5500 binocular open field auto refractometer and to compare it with dynamic retinoscopy technique (monocular estimation method). Methods: A cross–sectional study was conducted at the tertiary eye care centre. Subjects diagnosed with Down’s syndrome were recruited. Informed consent was obtained from parents and school authorities. Subjects underwent a complete ocular examination including visual acuity in LogMAR, objective and subjective refraction. Accommodative response was measured by monocular estimation method (MEM) and WAM 5500 binocular open field auto-refractometer. Accommodative response more than +0.75D was considered as lag of accommodation. Statistical analysis was carried out using a paired t-test at a confidence interval of 95%. Results: 43 Down’s syndrome subjects (22 males and 21females) with a mean age of 19.01±8.87 years were included. The mean spherical equivalent refractive error in the right and left eye was -0.83 ± 3.27D and -0.80 ± 3.28D respectively. The mean lag of accommodation with MEM was +0.76D ± 0.35D and with WAM5500 was +1.49D± 0.65D which showed statistical significant difference (p

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years back with good post-operative prognosis. She did not present any history of trauma, foreign body or any kind of stress to the eye. Objective measurements: On visual assessment her aided visual acuity was OD finger counting at 1 foot,

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