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Item Open Access Investigating contrast sensitivity as part of the assessment of visual requirements for driving(University of the Free State, 2023) Myburgh, Liani; Oberholzer, M.𝗕𝗮𝗰𝗸𝗴𝗿𝗼𝘂𝗻𝗱: The visual environment around a driver is altered by many factors such as weather, sun or light. Motor vehicle drivers need to be adaptable to different conditions and environments. Ninety percent of a driver’s sensory stimuli is interpreted by the visual system and a healthy functioning visual system is of utmost importance for a driver. Visual requirements for driving, currently, have no known global regulatory body and different visual requirements for drivers are found across the globe. In South Africa, two of the International Council of Ophthalmology (ICO) recommended visual requirements, are included (ICO, 2006). Current requirements include visual acuity (VA) and visual fields (VFs), but contrast sensitivity (CS) has been neglected from the requirements of vision for driving. The addition of CS is a valuable contributor to visual function, especially where different environmental conditions are concerned. Contrast sensitivity provides supplementary information about high contrast VA measurements, which may provide a better representation a driver’s vision in low light conditions such as dusk or dawn. 𝗣𝘂𝗿𝗽𝗼𝘀𝗲: The main aim of the study was to determine if motor vehicle drivers, who obtained their driver’s licences legally by passing the visual requirements for driving in South Africa (SA), would also be able to pass the criteria of a minimum CS requirement of 1.25 Log for each eye, as per Owsley et al. (2001) and Spreng et al. (2018). The importance of a driver requiring an optimal functioning visual system, representative under all types of light and contrast conditions, becomes evident in the constantly changing environmental conditions a driver faces during the act of driving. While VA is representative of vision during high contrast conditions, CS may better represent vision in low contrast conditions. 𝗠𝗲𝘁𝗵𝗼𝗱𝗼𝗹𝗼𝗴𝘆: This descriptive research study design recruited 110 participants, using a convenience sampling method. All participants were in possession of a valid South African driver’s license. To investigate whether additional visual requirements, such as CS should be included in the requirements for driving in SA, the current visual requirements (VA and VFs) as well as CS as an additional requirement, were investigated for possible associations with five variables (licence type, age, gender, known/diagnosed pathology, and previous ocular surgery). 𝗥𝗲𝘀𝘂𝗹𝘁𝘀: Thirteen point six percent of valid licenced drivers of the study population did not fulfil the visual requirements for their specific licence type at the time of data collection. Contrast sensitivity indicated statistically significant associations (p-value = ≤ 0.05) with age (p-value = 0.00 both eyes), licence type (p-value = right eyes 0.01, left eyes 0.00), known/diagnosed pathology (p-value = 0.00 both eyes), and previous ocular surgeries (p-value = 0.00 both eyes). Thus, CS measurements may be influenced by different licence types, age, known/previously diagnosed pathology, and previous ocular surgery. Arguably, if all participants were corrected to obtain a pass criterion for their specific visual requirements for driving (VA and VFs), 7.3% of these participants would still have failed the requirements if an additional minimum requirement of 1.25 Log for CS was included. 𝗖𝗼𝗻𝗰𝗹𝘂𝘀𝗶𝗼𝗻: Contrast sensitivity is an important and underrated visual function, especially in changing light conditions, not currently evaluated in the requirements for driving in South Africa. Contrast sensitivity is of clinical significance and may affect safe driving behaviour. The quality of vision of a driver may be compromised in the presence of reduced CS, even in the presence of good clinical VA and acceptable VFs.Item Open Access Myopia control: knowledge and attitude of newly qualified optometrists in South Africa(University of the Free State, 2023) Rawat, Nasrin; Naicker, NashuaInterest in myopia control has intensified due to increasing myopia prevalence globally. Due to the critical role of the optometrist in myopia control and the importance of undergraduate education in clinical decision-making, it is vital to explore the knowledge and attitude of newly qualified optometrists. This study aimed to describe the knowledge and attitude of new optometry graduates toward myopia control and their attitude toward the undergraduate education and training on the topic. The study utilised a cross-sectional, descriptive design where quantitative data was collected using a self-administered questionnaire. New graduates who qualified from an undergraduate optometry program in South Africa within the past 24 months were included in the study. An advertisement and a link to the study were circulated via social media and higher education institutions. The questionnaire contained a demographics section, three sections measuring the myopia control knowledge of participants, one section measuring attitude toward myopia control, and one section measuring attitude toward undergraduate education and training of myopia control. The closed-ended questions were scored, and Bloom’s cutoff point was used to grade the levels of knowledge and attitude measured. Validity of the instrument was ensured through face and content validity pre-data collection while factor analysis was conducted post-data collection. Internal consistency of the instrument was measured using Cronbach’s alpha post-data collection. The Department of Biostatistics, University of the Free State, supported the analysis of data and further analysis was performed using Statistical Package for Social Sciences Version 28. Frequencies and percentages were calculated for categorical data while interquartile ranges and medians were determined for numerical data. The Chi-square goodness of fit test was used to determine how representative the sample was of the population, and the Chi-square test of associations was used to determine if associations existed between the level of knowledge and levels of attitude found. A response rate of 57.6% (n=170) was reached within the data collection period. Most participants (58.2%) showed poor overall knowledge. Less than a quarter of participants were able to identify conditions that are associated with high myopia, such as posterior subcapsular cataract (24.12%), posterior staphyloma (18.82%), and choroidal neovascularisation (13.53%). The lowest performing section tested participants’ knowledge of myopia control strategies where a sizeable percentage of participants per question indicated that they were unsure about the success of the myopia control strategy presented (24.71-44.12%). While the attitude toward myopia control was largely neutral (68.82%), participants believed in the effectiveness of myopia control (85.88%) and acknowledged the need for myopia control (86.67%). Most participants (90%) also believed that myopia control belonged in optometric clinical practice. A majority of participants (82.35%) displayed a neutral attitude toward undergraduate education and training of myopia control. Clinical training of myopia control was deemed less adequate than the theoretical knowledge received at undergraduate level. Participants believed that undergraduate education required more lectures (89.41%), clinical training (87.06%), and emphasis (91.98%) on the topic of myopia control. An association between the knowledge and attitude of myopia control among participants was found to be statistically significant (p<.001). Although participants did believe in the effectiveness of myopia control and recognised its role in combatting increasing myopia prevalence, poor knowledge was predominant among participants. The knowledge gaps identified related to outdated information, poor interpretation, and poor knowledge of strategies used in myopia control. The neutral attitude toward myopia control found in this study could be improved by increased knowledge on the topic.Item Open Access The knowledge and attitudes of Grade R school teachers regarding the psychosocial impact of strabismus amongst school children(University of the Free State, 2020) Venter Jansen, Liza-Marie; Rasengane, T. A.; Van Rooyen, C.BACKGROUND: Negative social bias due to strabismus affects the self-esteem and learning process of a child. Social and educational milestones are already prioritised as early at a pre-primary school level. A Grade R teacher’s interaction with a child with strabismus can steer their functional development and influence their future quality of life. A lack of knowledge and an erroneous attitude ultimately contributes to the negative social stigma about strabismus. PURPOSE: The study aimed to determine the knowledge and attitudes of Grade R school teachers regarding the psychosocial impact of strabismus among school children. METHODS: A descriptive study was carried out from March to June 2018, through a structured questionnaire. RESULTS: Thirty-one female Grade R teachers, ages ranging between 24 and 62 years participated in the research study. The majority of the teachers (87.10%) were able to correctly identify a child with strabismus and refer them to treatment. Children with strabismus were thought of being at risk of struggling with areas of mathematics, language and life skills (64.52%). Nevertheless, the teachers had an overall positive attitude towards a photograph of a child with strabismus depicted in the questionnaire. The teachers described the strabismic child as happy, cute, healthy and intelligent. The teachers also suggested that a child with strabismus will be able to be a class representative (83.87%). The teachers were also aware that a child with strabismus may be at risk for developing a low self-esteem (identified by 83.87%) and to experience social anxiety (identified by 45.16%). CONCLUSION: The negative social biases towards strabismus are clearly defined in previous research. This study, however, contradicts previous findings. Not only did the Grade R teachers demonstrate a good understanding of the clinical aspects related to strabismus, but they also had an overall positive attitude towards strabismus in general.Item Open Access Perilimbal conjunctival pigmentation and its association with vernal keratoconjunctivitis in children from the West Rand(University of the Free State, 2021-02) Van Vuuren, Chandre; Kempen, E.Vernal keratoconjunctivitis (VKC) is a recurrent inflammatory disorder which affects the anterior ocular structures of pre-pubertal children resulting in preventable vision loss. Certain risk factors such as gender, warm and dry climates as well as systemic allergies, have been identified to increase the onset of VKC. Recently, perilimbal conjunctival pigmentation has been found to be a consistent and early indication of the development of VKC. Aim: The study aimed to evaluate the presence of perilimbal conjunctival pigmentation and its association with VKC in children from the West Rand, South Africa. Not only is there limited information regarding VKC in South Africa, but a gap has been identified in the literature concerning perilimbal conjunctival pigmentation in VKC and its association with ocular allergic responses and racial factors such as varying skin tones. This study was designed to provide a better understanding of these features and highlight the clinical relevance of the presenting pigmentation. With this knowledge, the appropriate ocular treatment of VKC can be provided, which may promote childhood eye care, especially in the West Rand. Methods: This study consisted of an observational quantitative study design employing cross sectional sampling. The sampling method consisted of non-probability convenience sampling. The data was collected through structured interviews and clinical examinations, which were performed to measure selected variables during a given period. The presence of VKC and perilimbal conjunctival pigmentation was determined through the symptoms reported by the participants during structured interviews. Furthermore, anterior and posterior ocular health examinations were performed with a slit lamp to identify VKC and perilimbal conjunctival pigmentation, based on a diagnostic criterion. The findings of the participants were divided into groups for the purpose of analytical non-parametric comparison to determine significant associations. Results: This study consisted of 125 participants between the age group of 6 and 12 years. The sample predominantly consisted of 68 female participants. The larger part of the sample population, being 75 participants, were of Black African race. Furthermore, most of the sample, 80 participants, resided in Krugersdorp. The findings of this study determined a VKC prevalence of 28% as well as a perilimbal conjunctival pigmentation prevalence of 28% in the sample population. Ocular pigmentation in the absence of VKC was found in 6.40% of the sample. More female participants displayed VKC (62.50%) while more male participants displayed both VKC and the perilimbal pigmentation (55.56%). Both VKC and perilimbal conjunctival pigmentation was identified more frequently in participants of 8 to 11 years of age. Furthermore, it was recognised that all the participants who displayed VKC and perilimbal conjunctival pigmentation were of the Black African ethnicity. The data also indicated that 62.96% of these affected participants resided in Kagiso, a local township settlement in the West Rand. Moreover, most of the participants displaying both VKC and the perilimbal pigmentation experienced ocular allergic responses in the form of symptoms such as ocular itching (96.30%) and clinical signs such as conjunctival hyperaemia (88.89%) and tarsal conjunctival papillae (88.89%). Conclusion: The results of this study has identified that age, gender, ethnicity and residential distribution affects the prevalence of VKC and perilimbal conjunctival pigmentation. Considering that all the affected participants were of the Black African race, a conclusion was made that a darker skin tone may increase the presence of perilimbal conjunctival pigmentation found in VKC. Most of the participants displaying both VKC and perilimbal conjunctival pigmentation experienced ocular inflammatory reactions in the form of ocular symptoms and signs. This identification signifies that the presence of allergic responses may intensify perilimbal conjunctival pigmentation. The study has determined that the presence of perilimbal pigmentation, which is found in VKC, is not only produced by the darker skin tones of an individual. The pigmentation is also induced by ocular allergic responses linked to this ocular disorder. Therefore, eye care practitioners may use this clinical sign to identify the early development of VKC to provide prompt treatment and encourage the promotion of ocular health amongst childrenItem Open Access Amplitude of accommodation in 9 to 13 year old school children of Mankweng circuit, Limpopo province(University of the Free State, 2020-09) Mafeo, M. E.; Oberholzer, M.; Rasengane, T. A.Background: Amplitude of accommodation (AA) is the function of accommodation referred to as the dioptric difference between the far point (the eye is at rest) and near point (when the eye is fully accommodated) and is known to reduce with increase in age. To determine if an individual has low, normal or high amplitude of accommodation (AA) for his / her age, norms calculated from Hofstetter’s formulae are still used as reference all over the world. However, these norms were found to be irrelevant to Ghanaian and Swedish children. Out of the few accommodation studies conducted in South Africa, none of the studies documented the AA of learners from the Mankweng circuit, Limpopo province in South Africa. Aim of the study: The aim of this study was to investigate the AA in 9 to 13 year old school children of Mankweng circuit, Limpopo province. Method: A cross - sectional, analytical, descriptive study was conducted on 291 learners aged 9 to 13 years of age (median age = 11.3 years). Learners were conveniently selected but schools were randomised. Learners who passed visual screening tests consisting of habitual visual acuity at 6 m and 40 cm right eye and left eye (RE and LE), +2.50 D lens test at 6 m (RE and LE), prism cover test at 40 cm and direct ophthalmoscopy (RE and LE), were included in this study. One hundred and eighty - five (185) learners met the inclusion criteria and proceeded to the measurements of AA which were determined subjectively using the push - up (PU) to - blur (first data set) and pull - away (PA) to - clear (second data set) techniques, and objectively using the dynamic retinoscopy (DR) (fourth data set). The PU and the PA results were thereafter used to determine the average AA for each participant, which were regarded as the third AA measurement data set for the current participants. Results: The subjective and objective techniques of measuring AA yielded different results among the same participants aged 9 to 13 years. Dynamic retinoscopy (DR) technique measured the highest AA (median = 19.7 D), with PU (median = 14.3 D), PA (median = 13.4 D) and the average results of PU / PA techniques (median = 13.8 D) measuring lower. The median AA were reducing from 21.2 D to 18.3 D as age increased in 9 to 13 year old participants when measured with DR; from 15.5 D to 12.9 D with PU; from 14.4 D to 12.2 D with PA and from 15.0 D to 12.5 D when using the average results of PU / PA measurements. The rate at which AA changed between different age groups was found to be inconsistent. Furthermore, a significant difference existed between the AA of groups of 2 years or more apart. There was no statistical significant difference between the AA in female and male participants. The results further showed that the type of technique used to collect AA measurements, may have influenced the prevalence rate of a LOW AA. The results showed a high prevalence of LOW AA with PA technique 18.4% (CI of [13.5% to 24.6%]), followed by the average results of PU / PA techniques 12.4% (CI of [8.4% to 18.0%]) and lastly PU technique 7.6% (CI of [4.6% to 12.3%]). For the same participants, the DR technique did not measure LOW AA amongst any of the age groups. In each technique, there were outliers reported, with the majority in the 9 - year - old age group. Conclusion: The measured AA decreased with increasing age with all the techniques used, although the rate of reduction was not constant between the age groups. Furthermore, the AA between the age groups 12 and 13 years was statistically significantly different and also between the age groups of two or more years apart (e.g. 9 and 11 years). The AA in female and male participants showed no statistical significant difference. The prevalence of LOW AA determined, was higher with the PA technique as compared to the PU technique. The objective measurements were statistically significantly higher to the subjective measurements.Item Open Access A vision checklist as a vision screening tool by Grade R to Grade 3 teachers in Quintile 1 schools(University of the Free State, 2020-08) Ramantsi, Boitumelo Monica Loraincia; Rasengane, T.A.; Jita, T.Background: Vision screening in schools has been shown to identify children with visual disorders who are thereafter referred for a comprehensive eye examination with an optometrist and or ophthalmologist. In South Africa, the government has introduced an integrated school health policy that includes vision screening which is conducted by few school health nurses, who cannot screen all school children. Teachers spend most of the time with children in their classrooms and thus, educating them on common vision disorders and training them to screen the learners in their classrooms can help identify children with vision disorders. Aim: This research aimed to investigate the use of a vision checklist as a screening tool by Grade R to Grade 3 teachers to detect visual disorders among learners in Bloemfontein. Methods: The study population comprised of 41 teachers and 1360 learners from the 11 Quintile 1 schools. Convenience sampling was done to enrol 36 teachers from 11 Quintile 1 schools and 1360 Grade R to Grade 3 learners aged between five and thirteen years around the Bloemfontein area in the study. The study was done in three phases. In the first phase of the research study, the researcher administered the first questionnaire with nine items to evaluate baseline teachers' knowledge and thereafter an educational session was done covering the most common visual disorders in children. A second questionnaire with nine items was administered after the educational session to assess the acquired knowledge of visual disorders and their management. The teachers were classified as having good knowledge if they obtain seven or more correct answers. The teachers were also trained on how to use the vision checklist in their classrooms as a vision screening tool. In the second phase of the study, the teachers screened the learners in their classrooms using the vision checklist. The learner would fail the screening if the teacher recorded any "no" response. In the last phase of the study, the research team screened learners from the two randomly selected schools (School A and School B) using the basic optometric vision screening tests to validate the screening results of the teachers. The two schools had 8 teachers and 261 learners from Grade R to Grade 3. The learner would fail the screening if any of the tests conducted were recorded as “fail”. The descriptive statistics and diagnostic tests were calculated per group. A p -value of less than 0.05 was considered to indicate statistical significance. Results: Phase 1: All 36 teachers who participated in this study were female whose ages ranged between 27 and 36 years. Most of the participants (n=16, 44.44 %) had been teaching for more than 10 years. The highest qualification attained by the participants was Bachelor of Education Honours (n=2, 5.56%), and most participants (n=10, 27.78 %) had an Advanced Certificate in Education. Thirty-four participants (94.44%) obtained a score of seven and higher in the first educational questionnaire. The second questionnaire results showed that all participants obtained a score of seven and higher. Twenty-one participants (58.33%) showed improvement in knowledge, while two participants (5.56%) regressed. Overall, there was a statistically significant difference ( p <0.0001) between the scores of participants before and after the educational. Phase 2 : A total number of 1360 Grade R to Grade 3 learners whose ages ranged from five to thirteen years old were screened by the 36 teachers using the vision checklist, five hundred and forty learners (39.7%) failed the screening. Phase 3 : The total number of children tested by both the teachers and the research team was 221; this was (84.67%) of the total amount of 261 learners in those schools. The research team found that 102 learners failed the vision screening, as a result the prevalence of the vision disorders in learners was 46% (95% CI: 39% – 53%). The teachers only identified 20 learners out of 102 to have vision disorders therefore, missed 82 learners with vision disorders. The sensitivity of the screening with a vision checklist was 19.61% (95% CI: 12% – 29%) and specificity of 83.19% (95% CI: 75% – 89%). Conclusion: The current study showed that teachers had adequate knowledge of common vision disorders in children which was improved through the educational session. However, the teachers missed 80% of the learners who had vision disorders when using the vision checklist as a screening tool. Thus, the results showed that the vision checklist used in this study was not a sensitive screening tool as it could only identify 19.61% of learners with vision disorders. It can be speculated that teachers’ current workload, large numbers of learners in classes and lack of motivation could have resulted in the high false-negative rate found in the study.Item Open Access Optimal time for post-operative refraction after uneventful cataract surgery(University of the Free State, 2020-09) Biddulph, Cara; Oberholzer, M.; Kempen, E.Item Open Access Use of diagnostic techniques by private practising optometrists in South Africa(University of the Free State, 2020-09) Fraser, Johanna Antoinette; Naicker, N.; Rasengane, T. A.Introduction: In South Africa, the optometric profession has seen two expansions of the scope of practice within the last two decades. The first of the two allowed optometrists to make use of techniques that required the use of diagnostic pharmaceutical agents. Aim: The purpose of the study was to establish the extent to which the four specific diagnostic techniques are utilised and if there exist barriers to their utilisation. Methods: A cross-sectional study was conducted to ascertain the utilisation of diagnostic techniques. The data was collected through a self-administered online questionnaire. The questionnaire contained questions on demographics, practice trends, utilisation of diagnostic techniques, as well as the registration status of the optometrists. Results: A total of 141 responses were received, and 118 were included for data analysis. There were 46 (39.0%) male participants and 72 (61.0%) were female. Ninety-eight (83.1%) of the participants had a diagnostic qualification, of which 49 (50.0%) were correctly registered with the HPCSA for diagnostic practice. Only 13.4% participants indicated that they performed contact tonometry at every visit, while slit-lamp fundus examinations was performed at every visit by 18.6% of the participants. BIO was only performed on indication by 20.8% of participants and gonioscopy was similarly only performed on indication by 34.7% of participants. Diagnostic techniques and procedures were mostly underutilised as many did not perform applanation tonometry (67.0%), binocular indirect ophthalmoscopy (79.2%), slit-lamp fundus examination (41.2%) and gonioscopy (64.3%). While optometrists were more confident in performing applanation tonometry (52.0%) and slit-lamp fundus examination (64.3%), confidence was considered a barrier for binocular indirect ophthalmoscopy (62.3%) and gonioscopy (54.1%). The lack of reimbursement was regarded as a significant barrier for 63.3% of participants, and 82.5% of respondents indicated the cost of acquiring the specific equipment was prohibitive. Most participants (92.8%) agreed that diagnostic privileges were appropriate for optometrists as well as the therapeutic scope of practice expansion (96.9%). Of those participants who were not correctly registered for diagnostic practice with the HPCSA, the majority (69.4%) were aware of the process to amend their registration status. The administrative process being too cumbersome and time-consuming was the most commonly stated barrier to amending the registration status of participants who were incorrectly registered. Conclusion: The study indicates that diagnostic techniques are mostly underutilised and optometrists prefer non-invasive alternative techniques over methods that are considered to be the gold standard. Another finding of the study is that there exists a discrepancy between the number of optometrists who are registered for diagnostic practice and the number of optometrists who have acquired a diagnostic qualification. It is recommended that an audit be done on the registration status of optometrists as to ascertain the correctness of the register and to have it amended if needed. It is further recommended that further studies should be done to ascertain the compliance of optometrists concerning their registrations and scope of practice. The reimbursement models need to be revisited, as well as the training of optometrists to ensure appropriate levels of confidence in diagnostic techniques amongst practitioners. These models should be geared towards professional services, emphasising the diagnosis and management of ocular diseases to motivate optometrists to practice more extensively within their full scope of practice.Item Open Access The prevalence of aniridia and associated visual and ocular complications among learners in schools for the visually impaired in central South Africa(University of the Free State, 2020-07) Hatia, Sherazadh; Rasengane, T. A.; Henderson, B. D.Introduction Aniridia is a rare, sight-threatening ocular disorder characterised by partial or complete absence of the iris. It can affect multiple ocular structures and lead to visual complications. According to our knowledge, there is currently no recent published research on aniridia in the South African population, thus it would be beneficial to investigate the prevalence of aniridia and describe the ocular and visual complications in South Africa. Therefore, the aim of this research was to determine the prevalence of aniridia among learners in visually impaired schools in central South Africa (Free State and North West) and to describe its visual and ocular complications. In order to achieve the aim, the number of participants that had partial and complete aniridia was determined using an ophthalmoscope. Thereafter, the visual and ocular complications in participants with aniridia were determined. Methods A prospective descriptive study was conducted on learners in three visually impaired schools in central South Africa. A total of 117 consenting learners were screened with an ophthalmoscope to determine the presence or absence of aniridia and only the participants identified with aniridia were further examined. The visual acuity of the participants with aniridia was determined using a logMAR visual acuity chart, the refractive error was determined using an autorefractor, the intraocular pressure was measured using an iCare tonometer to determine the risk for glaucoma and the anterior and posterior segment of the eye was examined using a slit lamp, 90D lens and gonioscopy lens to determine the complications associated with aniridia. Results for each participant were recorded and participants who required further management were referred to the local Ophthalmology clinic. Data analysis was performed by the Department of Biostatistics (University of the Free State). Prevalence was calculated by dividing the number of participants with aniridia by the total number participants included in the study. Results Four participants were identified as having aniridia and thus the prevalence of aniridia was found to be 3,4% (4 out of 117). The ages of these participants were 10, 13, 17 and 20 years. Visual acuity for each eye individually ranged from no light perception to 0.86 logMAR (6/38). Corneal complications such as pannus, opacification and vascularisation were seen in all of the participants. Some form of cataract was seen in all four participants. The IOP ranged between 11mmHg and 19mmHg in 3 of the participants and was outside of the normal range (7mmHg – 21mmHg) in the 4th participant. Gonioscopy showed 75% of participants with grade 4 angles and the remaining participant with grade 2 angles. Cup-to-disc ratios varied between 0.5 and 0.8 with no glaucomatous changes. Foveal hypoplasia was present in 75% of participants and nystagmus was present in all of the participants. One participant presented with membrane-like structures in the posterior chamber of both eyes, making a view of the fundus unobtainable. Conclusion The prevalence found (3,4%) is representative of one school (Christiana School for the Blind in the North West) from the three that were included, not the whole of South Africa. Cataracts and nystagmus were the most prevalent ocular complications found in this group. The foveal hypoplasia and corneal abnormalities in conjunction with some form of cataract and nystagmus are all contributors to the reduced visual acuity observed in these participants. The findings from this study contribute to new information regarding aniridia in regions of central South Africa and enables the comparison of results with research conducted in other parts of the world. This research also provides information about the most recent prevalence of aniridia in this part of South Africa. Further research can be done in other parts of the country to support and add to these results.Item Open Access A situational analysis of visual ergonomics and ocular symtoms among call centre agents: city of Tshwane call centres(University of the Free State, 2017-01) Tamenti, Gloria Tsholofelo; Rasengane, T. A.; Chikobvu, P.Introduction: The large municipalities or metros in South Africa are currently using call centres as a tool to deliver public services and provide access to public information. These call centres utilise computers, which are visually demanding. The aim of the study was to investigate the visual ergonomics of call centres and describe the working conditions in call centres, as well as estimate the prevalence of ocular symptoms associated with computer vision syndrome among call centre agents in the City of Tshwane call centres. Method: A cross-sectional, quantitative survey and observational study design was used to collect data among call centre agents. Data on demographics, occupation and ergonomics, visual information, as well as messages on symptoms experienced during and after computer work and ergonomics were gathered. Workstation measurements were taken, which consisted of viewing distances between computer screens and the eyes of the call centre agents as well as calculated viewing angles. Results A total of 175 call centre agents, aged between 21 and 63 years, participated in this study. The call centre agents were predominantly female (69%). About 62% of participants worked more than 8 hours per day and 38% worked 7-8 hours per day. All participants used desktop computers. Most participants (58%) spent more than 8 hours per day working on their computers during their working shift. Sixty three percent (63%) worked in a room with windows and 37% in a room without windows. The participants (90.29%) took breaks of 8.2 minutes on average in between work other than meal breaks. Most participants (61.7%) worked at further viewing distances from their computers than the recommended distance of 50-70cm. The examiner observed that 58% of participants had the centre of the computer at eye level. The mean viewing angle was 18.17 degrees. The mean room illumination for the three (3) call centres was 90.04 lux, which is notably below the recommended average of 350 lux. The most common ocular symptoms reported by the participants were tired, strained eyes (95.43%), increased sensitivity to light (83.43%), burning eyes (82.86%) and itchy eyes (82.86%). Musculoskeletal symptoms were reported, such as backache (89%), shoulder ache (87%), neck pain (84%) and neck stiffness (84%). The prevalence of ocular symptoms associated with computer vision syndrome was 69.66%. A higher prevalence of ocular and musculoskeletal symptoms occurred among participants who worked more than 8 hours and those who worked at a viewing distance of 71-90cm. Conclusion There is a need for appropriate lighting and the redesigning of workstations in the call centres of the City of Tshwane. This will help to reduce the prevalence of ocular and musculoskeletal symptoms associated with computer vision syndrome.