Article

Refractive errors, visual impairment, and the use of low-vision devices in albinism in Malawi

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Abstract

Background This study focuses onthe refractiveimplications of albinism in Malawi, which is mostly associated with the burden of visual impairment. The main goal was to describe the refractive errors and to analyze whether patients with albinism in Malawi, Sub-Saharan Africa, benefit from refraction. Methods Age, sex, refractive data, uncorrected and bestcorrected visual acuity (UCVA, BCVA), colour vision, contrast sensitivity, and the prescription of sunglasses and low vision devices were collected for a group of 120 albino individuals with oculocutaneous albinism (OCA). Refractive errors were evaluated objectively and subjectively by retinoscopy, and followed by cycloplegic refraction to reconfirm the results. Best-corrected visual acuity (BCVA) was also assessed binocularly. Results One hundred and twenty albino subjects were examined, ranging in age from 4 to 25 years (median 12 years), 71 (59 %) boys and 49 (41 %) girls. All exhibited horizontal pendular nystagmus. Mean visual acuity improved from 0.98 (0.33) logMAR to 0.77 (0.15) logMAR after refraction (p<0.001). The best improvement of VAwas achieved in patients with mild to moderate myopia. Patients with albinism who were hyperopic more than +1.5 D hardly improved from refraction. With the rule(WTR)astigmatismwasmorepresent (37.5 %) than against the rule (ATR) astigmatism (3.8 %). Patients with astigmatism less than 1.5 D improved in 15/32 of cases (47 %) by 2 lines or more. Patients with astigmatism equal to or more than 1.5 D in any axis improved in 26/54 of cases (48 %) by 2 lines or more. Conclusions Refraction improves visual acuity of children with oculocutaneous albinism in a Sub-Saharan African population in Malawi. The mean improvement was 2 logMAR units.

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... Udeh et al. [15] and Ajose et al., [24] in other parts of Nigeria. Other developing countries with similar socioeconomic status such as Nepal, [13] Malawi [25] and Cameroun [26] also had similar findings. It is said that the subnormal presenting visual acuity seen in persons with albinism may be due to delayed visual maturation, foveal hypoplasia, nystagmus, strabismus and iris trans-illumination. ...
... This is not surprising as activities associated with contrast sensitivity such as driving at night or in the rain and navigation in unfamiliar surroundings (during business activities) are commonly undertaken by adults. Similar findings of impaired mean contrast sensitivity was noted in Chicago [21], Malawi [25] and Egypt [28]. Factors thought to be responsible for the degradation in contrast sensitivity include increased central retinal cone spacing, abnormal decussation of the visual pathway and glare from iris hypopigmentation, nystagmus and foveal hypoplasia. ...
... This higher percentage of nystagmus in Udeh's study may not be unconnected with the inclusion criteria for nystagmus which included minimal nystagmus detectable by slit lamp examination unlike this study where only those with obvious nystagmus were considered. Other differing studies [25,29] with similar methodology as Udeh's also reported universal presence of nystagmus. Underdevelopment of the fovea and delayed visual maturation seen in PWA is often considered to be responsible for the development of nystagmus. ...
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Aim: To determine the pattern of ocular disorders in persons with albinism and how they affect visual function. Methods: This was a descriptive cross-sectional study conducted over a five-month period on persons living with albinism in Southern Nigeria. The study participants were randomly selected during the monthly meetings of a support group known as The Albinism Foundation (TAF).Visual acuity and contrast sensitivity were assessed using the ETDRS visual acuity chart and Pelli Robson contrast sensitivity test chart. A comprehensive eye examination including dilated fundoscopy was also carried out to determine other ocular disorders. Data was analyzed using SPSS version 22 and statistical significance was set at a p-value ≤ 0.05. Results: A total of 116 PWA (232 eyes) were examined. There were 44 (37.9%) males and 72 (62.1%) females. The age of the study subjects ranged from 5 to 56 years. Most eyes were visually impaired for both distance (n=228; 98.3%) and near vision (n= 224; 96.6%). Contrast sensitivity in most eyes (n=138; 59.5%) was subnormal. With refraction and Low Vision Aid (LVA), there was significant improvement of the mean VA by 2-3 acuity lines and 6 acuity lines respectively (p=0.000). All the examined eyes had fundus hypo-pigmentation, 91.4% (n=212) had iris trans-illumination, 86.2% (n=200) had nystagmus, and 34.4% (n=80) had strabismus. Nystagmus, strabismus and iris trans-illumination significantly (p=0.00) reduced visual acuity and contrast sensitivity. Conclusion: Most study participants had reduced distance visual acuity and contrast sensitivity but with correction there was a significant improvement in vision. The presence of nystagmus, strabismus and iris trans-illumination were observed to contribute to the poor vision experienced by most persons living with albinism. Hence, early optical intervention and counselling is important in improving the quality of living of persons with albinism.
... [6,7] People with OCA also have a wider range of refractive errors including high with-the-rule astigmatism. [7,8] As compare to the normal pigmented retinas, the photoreceptor outer segment of the retina of people with albinism does not develop normally. [9] In addition, the lack of pigment in people with OCA also results in the abnormal decussation and misrouting of the optic nerve fibers during the development resulting in poor vision. ...
... Similar improvement in functional vision with low vision aids in people with OCA has been reported in the literature. [8,19,20] As identified in the literature, [8,16,18] this study also showed that higher spherical and astigmatic refractive errors and with-the-rule astigmatism are associated with OCA. The distributions of spherical-equivalent and astigmatic refractive errors are broader in our participants with OCA. ...
... Similar improvement in functional vision with low vision aids in people with OCA has been reported in the literature. [8,19,20] As identified in the literature, [8,16,18] this study also showed that higher spherical and astigmatic refractive errors and with-the-rule astigmatism are associated with OCA. The distributions of spherical-equivalent and astigmatic refractive errors are broader in our participants with OCA. ...
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Purpose: All people with oculocutaneous albinism (OCA) have reduced vision. This study aimed to assess the benefits of low vision aids for people with OCA. Methods: Seventy-seven consecutive people with OCA age 4 years and above examined in a low vision clinic were included in the study. Uncorrected and best-corrected visual acuity (VA), VA with low vision devices, types of low vision aids, and refractive errors data were analyzed. Results: Of the 77 people with OCA, 57% were in the age group between 4 and 15 years and 43% in the age group of 16 years and above. At the time of presentation, the percentages of visually impaired, severe visually impaired, and blind (using WHO low vision criteria) were 52%, 22%, and 25%. Among them, 39% has near VA of 1 M or better. Difference in the means of the spherical equivalent refractive error in the right eyes and left eyes was -0.494 diopters (-01.686, 0.699; 95% confidence interval). VA improved significantly after adequate refractive correction by more than one log MAR lines in 38.6% (P < 0.01). With low vision devices, in 85.7% (n = 66) participants, VA was enhanced to normal level (6/18 or better) in the better eye while 7.8% still remained in the blind category. Telescopes were prescribed to 61% people for the enhancement of distance VA and hand hold magnifiers were prescribed to 22% people to meet their needs. Conclusion: Low vision aids can be successfully used in visual rehabilitation of people with OCA to meet their needs.
... An understanding of the visual function in adolescents with OCA and their QoL in terms of their visual ability will assist in the holistic management of these individuals. In this study, the mean best-corrected VA was approximately 0.81 logMAR in each eye and is similar to the results of other studies that included only individuals with OCA (Schwering et al., 2015;Wildsoet et al., 2000). This is noteworthy as individuals with OCA have poor VA as a result of foveal hypoplasia, retinal hypopigmentation, and degradation of the retinal image due to iris transillumination and nystagmus (Healey et al., 2010). ...
... In the present study, the refractive error findings showed interesting trends. In contrast to previous studies, only 40% of participants required spectacles, which is unexpected as OCA is usually associated with high refractive errors (Healey et al., 2010;Jhetam & Mashige, 2019;Schwering et al., 2015;Udeh et al., 2014). Although less than half of the participants had refractive errors, the presence thereof underscores the need for routine eye examinations in the management of VI. ...
... This is supported by a previous study that reported that although the etiology of VI in albinism is multifactorial, refractive anomalies contribute significantly to the vision loss experienced by these individuals (Udeh et al., 2014). A mean myopic refractive error was found in both eyes, and is similar to the results reported in other studies (Khanal et al., 2016;Sampath & Bedell, 2002;Schwering et al., 2015). In this study, WTR astigmatism was most common followed by oblique astigmatism. ...
Article
Individuals with ocular and oculocutaneous albinism (OCA) have significantly reduced visual acuity (VA) resulting in visual impairment (VI). The aim is to report on the visual function of adolescents with OCA and their quality of life (QoL) in terms of their visual ability. A total of 28 adolescents with OCA participated in this study. Tests of visual function included distance VA, refractive error, contrast sensitivity (CS), and colour vision. The Cardiff Visual Ability Questionnaire for Children (CVAQC) was used to assess visual ability. All participants presented with cutaneous hypopigmentation and nystagmus, while only two had strabismus. A mean myopic refractive error was found, and with-the-rule (WTR) astigmatism was most common. The mean best-corrected VA was 0.81 ± 0.17 logMAR and 0.81 ± 0.18 logMAR in the right and left eyes, respectively. The mean CS with the best refractive correction was 1.23 ± 0.33 log CS in the right eye and 1.29 ± 0.33 log CS in the left eye. The mean Cardiff visual ability score was −0.37 ± 0.79 log units. The variation of refractive errors and the magnitude thereof underscores the need for regular eye examinations in individuals with OCA. The majority of participants had moderate VI, and these participants had a better mean Cardiff visual ability score than those with severe VI. Similarly, participants with normal binocular CS had a better Cardiff visual ability score than those with a loss of CS.
... 4 The prevalence of OCA in Southern Africa has been reported to range between 0.02% and 0.1%, with a male to female ratio ranging from 0.8 to 1.4:1. 5,6,7,8,9,10,11 Several eye and vision problems including ocular hypopigmentation, reduced VA, nystagmus, strabismus and photophobia are associated with albinism. 12 Refractive error changes have also been reported to be prevalent in albinism. ...
... 8,13,14,15,23,24 Reduced vision may result from refractive error, misalignment of the eyes, reduced pigments in the macula, misrouting of optic nerve fibres, amblyopia and nystagmus, 15 The results of uncorrected VA obtained in the current study also agree with findings reported in other studies. 11,26,27 Optical correction improved distance logMAR VA up to a range of 0.40 logMAR -1.10 logMAR. Raliavhegwa 8 also reported an improvement in distance logMAR VA following optical correction in a study conducted in the Limpopo province of South Africa among children with OCA. ...
... In addition, Sacharowitz 14 reported significant improvements with optical correction in distance vision of 60% (n = 40) of patients with albinism presenting at a low vision clinic at the university. Other studies 11,27 reported similar improvements in the mean logMAR distance VA following optical correction. Clinically, the improvement of distance vision ranged from 4 letters (0.08 logMAR) to 9 letters (0.18 logMAR). ...
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Background: Oculocutaneous albinism results in defects of the visual pathway and ocular structures. Aim: To determine the ocular findings and vision status of learners with oculocutaneous albinism (OCA) as well as to establish the level of visual acuity, contrast sensitivity and reading rate improvements following optical correction. Setting: Three special education schools in KwaZulu-Natal, South Africa. Methods: A total of 81 learners with OCA participated in this study. Testing procedures included logMAR distance and near visual acuity (VA) measurements, cover tests, retinoscopy (dry), subjective refraction, tangent screen, ophthalmoscopy, contrast sensitivity and reading rate determination. Results: The majority of participants (96.3%) had wheat straw coloured hair and 95.1% had grey irides. All the learners presented with iris-transillumination and an absent foveal reflex and all but one exhibited nystagmus. Esophoria and esotropia represented 72.8% of binocular vision anomalies. Myopic astigmatism was noted in 41.4% of the learners while with the rule astigmatism was predominant (64%). Following optical correction, VA significantly improved from a range of 0.50 to 1.40 logMAR to a range of 0.5 to 1.06 logMAR for distance (p < 0.05) and from a range of 0.40 to 1.30 logMAR to a range of 0.30 to 1.08 logMAR) for near (p < 0.05). In addition, contrast sensitivity improved from a range of 0.48 to 1.92 logCS to a range of 0.88 to 1.92 logCS (p < 0.05). However, the reading rate did not show any significant improvement following optical correction (p> 0.05). Conclusion: Learners with OCA exhibited various ocular and vision defects which impair visual functions. Their VA and contrast sensitivity could be significantly improved with optical correction; however, their reading rate was not improved.
... Visual function in patients with OCA1 is affected by unpredictable combinations of ocular motor (eccentric null zones, damping with convergence, monocular intensity changes, periodicity, strabismus, poor smooth pursuit and OKN and attentional changes) and sensory system defects (ammetropia, amblyopia, photosensitivity, loss of contrast sensitivity, poor motion perception, decreased temporal luminance, impaired contour interaction, light interference and pre-chiasmal, chiasmal, and post-chiasmal, maldevelopment) [1,2,4,7,11,21,22,38- 40]. Visual functions directly affected include high spatial acuity vision, contrast sensitivity, motion detection, visual recognition time, gaze and time dependent vision, depth and stereopsis, smooth pursuit, and vestibular and proprioceptive functions [1,2,4,7,11,21,22,[38][39][40]. ...
... Despite these public interventions, the plight of persons with albinism in Malawi is still a major concern. Scholars such as Braathen and Ingstad (2006), Lynch et al. (2014), and Schwering et al. (2015) have conducted albinism research in Malawi (2015). Despite the fact that such studies have been conducted, little is known about the challenges faced by PWAs in Malawi. ...
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Background Albinism is a genetic condition caused by a deficit in the production of the pigment called melanin, which protects the skin against ultraviolet light and provides the skin with its color production. The condition may predispose persons with albinism (PWAs) to lifelong physical and health problems, such as visual impairment and ultra-violet induced skin damage. Due to this condition, we explored the challenges faced by persons living with albinism as they socialize in Lilongwe District, Malawi. Method The study adopted an interpretative phenomenological approach and included 30 participants comprising 13 females and 14 males with albinism and three key informants from Association of People with Albinism in the Lilongwe district in Malawi. Data were collected through in-depth interviews and focus group discussions. Van Manen's (2014) six steps of phenomenological analysis was used to analyze all data. Results People with albinism face a variety of problems, the most common of which are financial constraints, health complications due to a lack of adequate medical care, a lack of community support leading to stigma and discrimination, and superstitious beliefs. Conclusions People with albinism suffer socially as a result of misconceptions, behaviours, social isolation, labelling, and beliefs that are negatively correlated with their disorder. PWAs face these problems as a result of public misunderstanding about albinism.
... This relationship can also be clearly seen independently in males and females (Fig E in S1 File). The link between corneal astigmatism and deficiency in melanin production has been previously reported for albinism [33]. Our data suggests that darker skin and hence possibly increased melanin production appears protective for corneal astigmatism. ...
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Purpose To describe corneal astigmatism in the UK Biobank population and to look for associations with other biometric variables and socio-demographic factors. Methods This analysis included a subsample of 107,452 participants of the UK Biobank study who underwent an enhanced ophthalmic examination including autorefractor keratometry (Tomey RC 5000, Tomey Corp., Nagoya, Japan). Participants were recruited from across the United Kingdom between 2006 and 2010, and all were between 40 to 69 years. After quality control and applying relevant exclusions, data on corneal astigmatism on 83,751 participants were included for analysis. Potential associations were tested through univariable regression and significant parameters carried forward for multivariable analysis. Results In univariable analysis, the characteristics significantly associated with higher corneal astigmatism (P<0.001), by order of magnitude were, female gender, white ethnicity, lighter skin colour, use of UV protection, lower alcohol intake, lower corneal-compensated intraocular pressure (ccIOP), older age at completion of education, younger age, higher Townsend deprivation index, lower height and lower systolic blood pressure. After inclusion in the multivariable analysis, gender, skin colour, alcohol intake, age at completion of full-time education, ccIOP, age and Townsend deprivation score remained significant (all P<0.001). Increased corneal astigmatism was also found to be significantly associated with amblyopia or strabismus. Conclusions This analysis confirms previous associations with astigmatism such as younger age and female gender, and identified novel risk factors including lighter skin colour, lower alcohol intake, later age having completed full time education later, lower ccIOP and higher Townsend deprivation index. Further research is needed to investigate these novel associations.
... Our observations in this study is similar to the results reported by Udeh., et al. and Ajose., et al. in other parts of Nigeria[11,13]. Other developing countries with similar socioeconomic status such as Nepal, Cameroun and Malawi also had similar findings[17][18][19]. It has been postulated that the subnormal presenting visual acuity may be due to delayed visual maturation, foveal hypoplasia, nystagmus, strabismus and iris trans-illumination.Anderson., et al. in the United States of America however, reported a better mean uncorrected distance and near visual acuity of 0.73 logMAR (6/32 Snellen) and 0.31 logMAR (N6) respectively [20]. ...
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Purpose To describe corneal astigmatism in the UK Biobank population, to look for associations with other biometric variables and socio-demographic factors, and to report the proportion with abnormal keratometry and irregular astigmatism suggestive of pathological corneal ectasias such as keratoconus. Methods Cross-sectional data were obtained from UK Biobank (www.ukbiobank.ac.uk/). A subsample of 107,452 participants from UK communities had undergone an enhanced ophthalmic examination including autorefractor keratometry (Tomey RC 5000, Tomey Corp., Nagoya, Japan). After quality control and applying relevant exclusions, data on corneal astigmatism on 83,751 participants was available for analysis. Potential associations were tested through univariable regression and significant parameters carried forward for multivariable analysis. Results In a univariable analysis, the characteristics significantly protective against corneal astigmatism were gender (male), older age, darker skin colour and increased alcohol intake (all p<0.001). The parameters significantly associated with increased corneal astigmatism were older age at completion of full time education, use of UV protection and lower corrected visual acuity. After inclusion in the multivariable analysis, age, gender, age at completion of full time education, corrected visual acuity and skin colour remained significant (all p<0.001). Increased corneal astigmatism was also found to be significantly associated with amblyopia or strabismus. No individuals with abnormal keratometry or irregular astigmatism were reported. Conclusions This analysis of associations with astigmatism in a large cohort of volunteers confirms previous associations including adverse associations with younger age and female gender, and identified novel associations including darker skin colour and frequency of alcohol intake. The highest risk group for corneal astigmatism were younger females of lighter skin colour, having completed full time education later, with higher logMAR corrected visual acuity. We also confirmed that corneal astigmatism is a high risk factor for amblyopia and strabismus. Finally since no cases of keratoconus were identified, this would suggest that simple keratometry indices may not be sufficient for population screening of keratoconus.
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• The eyes of a 13-year-old leukemic boy with the attributes of tyrosinase-negative oculocutaneous albinism were obtained for light and electron microscopic study. Repeated examinations had failed to reveal WBCs with giant oxidase-positive granules, and leukemic involvement of the fundus never occurred. Light microscopic examination of horizontal and vertical sections through the retina confirms earlier reports that the fovea is absent in albinos. The synaptic apparatus of the photoreceptor terminals appears abnormal. The rough endoplasmic reticulum of the retinal pigment epithelial cells is sparse though the presence of phagosomes suggests that phagocytic function is intact. Suggestions as to the importance that the morphological findings may have on albino visual function are made.
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To evaluate the prevalence of refractive errors in different subtypes of oculocutaneous albinism, and to see if there is any correlation between refractive errors and final visual outcome in this population. This is a retrospective study of 132 albino patients, ranging in age from 0.5 to 35 years. They were divided into four subtypes: OCA1A, OCA1B and OCA1C, and OCA2. Refractive errors were evaluated objectively by cycloplegic refraction and subjectively in cooperative patients. Best corrected visual acuity was assessed binocularly. Refractive errors were divided into three groups--hypermetropia, myopia and astigmatism--to avoid the use of spherical equivalent. Refractive errors were mainly astigmatism and hypermetropia. The OCA1A group showed high hypermetropia (≥ 5 dioptres) in 43.4% of patients, reaching significantly higher levels than in other subgroups (p=0.007). Mean visual acuity in logMAR was: OCA1A=0.81, OCA1B=0.64, OCA1C=0.61 and OCA2=0.48. Astigmatism averaged 2.1 dioptres (consistently with-the-rule), and it was homogeneously distributed between all subgroups (53%). The poorest visual acuity was found in those with OCA1A, which was associated with the highest rate of high hypermetropia (statistically significant different from other subgroups). Astigmatism was the most common visually significant refractive error across all subtypes of albinism. These results may help to clarify the prevalence of refractive errors in albino patients and aid the prediction of visual outcome in this heterogeneous population.
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The eyes of a 13-year-old leukemic boy with the attributes of tyrosinase-negative oculocutaneous albinism were obtained for light and electron microscopic study. Repeated examinations had failed to reveal WBCs with giant oxidase-positive granules, and leukemic involvement of the fundus never occurred. Light microscopic examination of horizontal and vertical sections through the retina confirms earlier reports that the fovea is absent in albinos. The synaptic apparatus of the photoreceptor terminals appears abnormal. The rough endoplasmic reticulum of the retinal pigment epithelial cells is sparse though the presence of phagosomes suggests that phagocytic function is intact. Suggestions as to the importance that the morphological findings may have on albino visual function are made.
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The eye of a 47 year old man with tyrosinase-positive oculocutaneous albinism, photophobia, nystagmus and visual acuity 0, 4-0, 5 was histologically examined after orbital exenteration for neoplasia. Histologic serial sections of the centre of the retina showed a continuous 6-8 cell-layer of ganglion cells, without any suggestion of a foveolar pit. The outer layers of the macular retina were altered secondarily by tumor-impression-folds; they were unremarkable at the periphery as were the acid mucopolysaccharides in the receptor region. Electron microscopy of the uvea and the retinal pigment epithelium showed a normal number of pigment granules but a deficiency of melanin, as well as structural anomalies. The absence of the foveolar pit and the decrease of visual acuity in tyrosinase-positive albinism is caused by definite morphologic alteration in the arrangement of ganglion cells in the macular region in the sense of a foveolar aplasia. The etiology is discussed. An identic anomaly has been described in aniridia, similar ones in other congenital ocular diseases.
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This paper reviews some studies done on the psychological aspects of albinism. Studies on the intellectual ability of albinos produce equivocal results. Results from personality studies seem more consistent and show albinos to be more emotionally unstable than non-albinos. This paper also reports a study by the author which examines the phenomenon of albinism from the albino's viewpoint. It examined the responses of three undergraduate albino subjects--one female and two males--to the author's request for each to write an essay on the merits and demerits of being an albino based on personal experiences. All consider being an albino to be more of a demerit than a merit. The demerits include conspicuous colour, delicate skin which blisters under the sun, defective sight, interpersonal, especially heterosexual, problems and society's unkind attitude. The paper ends with a discussion of possible future research in the area and a recommendation of the need for psychological rehabilitation as part of the management programme for albinos.
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Albinism involves the mutation of one or more of the genes associated with melanin synthesis and has many ramifications for vision. This study focuses on the refractive implications of albinism in the context of emmetropization. Refractive, biometric, and visual acuity data were collected for a group of 25 albino individuals that included the following: 18 oculocutaneous (13 tyrosine positive, 5 tyrosine negative); 7 ocular (2 autosomal recessive, 5 sex-linked recessive). Their age range was 3 to 51 years. All exhibited horizontal pendular nystagmus. There were no statistically significant differences relating to albino subtype for any of the measured parameters. All the subjects had reduced visual acuity (mean: 0.90, logMAR) and overall, there was a bias toward hyperopia in their refractive errors (mean: + 1.07 D). However the refractive errors of the group covered a broad range (SD: 4.67 D) and included both high myopia and high hyperopia. An axial origin to the refractive errors is implied by the high correlation between refractive errors and axial lengths. Refractive astigmatism averaged 2.37 D and was consistently with-the-rule and highly correlated with corneal astigmatism, which was also with-the-rule. Meridional analysis of the refractive data indicated that the vertical meridian for hyperopic subjects was consistently nearer emmetropia compared to their horizontal meridian. Myopic subjects showed the opposite trend. The overall refractive profile of the subjects is consistent with emmetropization being impaired in albinism. However, the refractive errors of hyperopic subjects also can be explained in terms of "meridional emmetropization." The contrasting refractive profiles of myopic subjects may reflect operational constraints of the emmetropization process.
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We compared retrospectively the distribution of refractive errors in a sample of adolescent and adult albinos (n = 19) with that in persons with idiopathic congenital nystagmus (CN) (n = 46), whose eye movements are similar to those of albinos but whose visual acuity is better. The distribution of spherical-equivalent refractive errors is more broadly distributed and slightly less myopic in albinos than in persons with idiopathic CN. On average, albinos also have more astigmatism (primarily with-the-rule), than persons with idiopathic CN. Unlike the leptokurtic distribution of refractive error that characterizes the normal adolescent and adult population, the distributions of refractive error for albinos and for persons with idiopathic CN exhibit no significant kurtosis. Moreover, neither group of subjects exhibits significant kurtosis for refractive errors in the vertical meridian, which corresponds to the retinal-image orientation with the least motion smear during horizontal nystagmus. The absence of significant leptokurtosis in the refractive-error distributions of young-adult albinos and persons with idiopathic CN suggests that the presence of nystagmus may interfere with normal refractive development.
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Patients with albinism have varying degrees of reduced vision, strabismus, iris transillumination, nystagmus, fundus hypopigmentation, and foveal hypoplasia. High refractive errors are common, but reduced vision persists due to nonrefractive factors, causing reluctance by some clinicians to prescribe spectacles. We sought to evaluate the effect of spectacle correction of refractive error on clinical findings and recorded compliance with refractive corrections, as little detailed data exist. We prospectively examined 35 consecutive patients with albinism for whom glasses had been prescribed to determine if objective improvement in recognition visual acuity (VA), strabismus, anomalous head posture (AHP), fusion, or stereoacuity occurred with refractive correction. Parents or patients reported compliance with glasses wear (excellent: >75% of awake hours; good: 50-75% of awake hours; fair: 26-50% of awake hours; poor: <25%). Median age was 9.5 years (range: 3 to 30). Median refractive correction was 1.875 D spherical equivalent (range: -9.75 to +8.88 D). Glasses wear was initiated at a median age of 14 months (range: 3 months to 14 years). Mean binocular VA at distance was 20/80.9 corrected and 20/107.6 uncorrected ( P < 0.001). Mean VA at near was 20/28.4 corrected and 20/41 uncorrected ( P < 0.001). Mean strabismic deviation was 7.2 PD with glasses and 10.0 PD without glasses at distance ( P = 0.006) and 10.8 PD with glasses and 14 PD without glasses at near ( P = 0.042). Mean AHP at distance was 8.3 degrees with glasses and 7.3 degrees without glasses at distance ( P = 0.327) and 4.7 degrees both with and without glasses at near ( P = 0.308). Twenty-one patients had fusion with or without glasses, two had fusion only with glasses, and one patient had fusion only without glasses. The other patients did not have any detectable degree of fusion. Twenty-seven individuals had no stereoacuity with or without glasses, five had gross stereoacuity of 3000 seconds of arc both with and without glasses, and three had gross stereoacuity only while wearing glasses. Compliance was excellent in 29 patients, fair in four, and poor in two. This prospective study showed a significant improvement in corrected VA and alignment in persons with albinism, despite overall subnormal acuity. Some individuals also experienced improvement in binocular alignment and AHP. Compliance with spectacles was generally good. Therefore, refractive correction should be encouraged in persons with albinism as improvement in visual function is likely to occur.
Education of children and young people with albinism in Malawi
  • P Lynch
  • P Lund
Lynch P, Lund P (2011) Education of children and young people with albinism in Malawi. Ministry of Education, Science, and Technology Malawi. Final report. Commonwealth Secretariat, London, pp. 5-6