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1 1 PREVALENCE OF EYE DISEASES AMONG SCHOOL CHILDREN IN A RURAL SOUTH EASTERN 2 NIGERIAN COMMUNITY. (Original Research) 3 Dr Obiekwe Okoye*, FMCOph 4 University of Nigeria Teaching Hospital, Enugu, Nigeria 5 Mobile phone +2348037007163 6 7 8 9 10 11 E- mail: [email protected] 12 Professor (Mrs) Rich Umeh, FMCOph 13 University of Nigeria Teaching Hospital, Enugu, Nigeria 14 Mobile phone +2348033324691 15 16 17 18 19 20 E- mail: [email protected] 21 Professor Felix Ezepue, FMCOph 22 University of Nigeria Teaching Hospital, Enugu, Nigeria 23 Mobile phone +2348036766673 24 25 26 27 28 29 30 31 32 E- mail: [email protected] Contribution to manuscript: concept, data collection, data analysis, literature search, writing of manuscript. A registered member of Rural and Remote Health Journal Contribution to manuscript: literature search, data analysis, writing of manuscript, review of manuscript Not registered with Rural Remote Health Journal Contribution to manuscript: literature search, data analysis, writing of manuscript, review of manuscript Not registered with Rural Remote Health Journal * Corresponding Author This research was funded by the Federal Ministry of Health Of Nigeria. 2 33 ABSTRACT 34 Introduction 35 Vision plays an essential role in development and visual deficit constitutes a risk factor not only 36 for visio-sensory development, but also for overall socio-economic enhancement. Timely 37 screening for the early detection of eye and vision problems in children is vital to avoid lifelong 38 visual impairment. Early detection provides the best opportunity for effective treatment. There 39 is paucity of data regarding causes of eye diseases among rural children in Nigeria. The aim of 40 this study is to determine the prevalence and causes of eye diseases among children residing in 41 rural communities in Nigeria. 42 Methods 43 A cross sectional survey to determine the prevalence and common causes of ocular morbidities 44 in primary school children in Abagana - a rural community in Njikoka Local Government Area of 45 Anambra State South East of Nigeria. The available children in all the 8 existing primary schools 46 in the community who are aged between 6 and 16 years were registered, interviewed and their 47 eyes examined. Data were analyzed for age, sex, types of ocular disorders and causes of visual 48 impairment. Frequency and 49 parametric method. 50 Results 51 The 52 females, a male female ratio of 1.07/1 .Ocular disorders were found in 127(6.1%) of the 53 population. The most common ocular disorder in this community were vernal conjunctivitis 54 61(2.9%) followed by refractive error 14(0.7%)(. percentages were calculated with univariate analysis and census population consisted of 2092 children, 1081(51.7%) males and 1011(48.3%) 3 55 56 Conclusion 57 The commonest cause of eye disease among rural children surveyed is vernal conjunctivitis 58 followed by refractive error. Findings in this study indicate that most of the causes of visual 59 impairment were due to amblyiopia which is avoidable. Early detection through early eye 60 screening, health education and provision of access to adequate eye care facility will reduce the 61 burden of eye disease and blindness among rural Nigerian children. 62 Key Words; Children, Eye disease, Nigeria, Rural, school. 63 4 64 Introduction 65 66 67 The prevalence of blindness in children varies from approximately 0.3/1,000 children in wealthy regions of the world, to 1.2/1,000 in the poorer countries/regions[1]. 68 Blindness among children is more common in the poor region of the world for three 69 main reasons[2]: First, there are diseases which can lead to blindness from causes which are no 70 longer prevalent in industrialized countries but are still prevalent in poor regions of the world, 71 such as measles, vitamin A deficiency, and ophthalmia neonatorum. Second, there are fewer 72 well equipped facilities and personnel trained in managing treatable causes of blindness in the 73 poorer countries. Third, is the contribution of ignorance, poverty and superstition to the 74 disease causation, propagation, treatment and prevention in the rural areas. These factors 75 collectively impact negatively on perception of eye diseases and encourages use of harmful 76 traditional eye medications which in turn can result to avoidable blindness. 77 Incidence data are very difficult to obtain, but it has been estimated that there are 8 new 78 blind children for every 100,000 children each year in industrialized countries[2].In the 79 developing countries, approximately 500,000 children become blind every year – one every 80 minute and about half of them die within one or two years of becoming blind[3]. Available data 81 indicate that the prevalence of childhood blindness varies from 1.2/1000 children in very low 82 income region of the world to 0.3/1000 children in high income region[4]. 83 84 The high number of blind years resulting from blindness during childhood is one of the 85 reasons why the control of childhood blindness is a priority of the World Health 5 86 Organization/International Agency for Prevention of Blindness (WHO/IAPB) Vision 2020: The 87 Right to Sight Programme[5]. 88 Children who are blind have to overcome a lifetime of emotional, social and economic 89 difficulties, which affect the child, the family and the society[6]. Loss of vision in children 90 influences their education, employment and social life[6]. Childhood blindness is second only to 91 adult cataract as a cause of blind-person years. Approximately 70 million blind-person years 92 are caused by childhood blindness worldwide[7]. 93 Vision plays an essential role in development and visual deficit constitutes a risk factor 94 not only for visio-sensory development, but also for overall development[8]. Timely screening 95 for the early detection of eye and vision problems in children is vital to avoid lifelong visual 96 impairment. Early detection provides the best opportunity for effective treatment[9]. 97 98 It has been recognized world wide even in developed economies that there is great vision 99 benefit from regular eye screening of children. This should include a comprehensive eye 100 examination. Depending on the findings, early institution of corrective measures will go a long 101 way in reducing the current magnitude of childhood blindness and morbidity. In a study among 102 school children in Oman[10], 28,765 (6.9%) of the 416,157 children examined were found to 103 have defective vision. Abdul Rasheed Qamar advocated for a regular eye screening of 104 children[11]. Out of total of 38575 schoolchildren examined 2065 (5.3%) were found to have 105 refractive errors. Early treatment will reduce the incidence of avoidable childhood visual 106 impairment and blindness. 107 6 108 School-age children (6 –15 years) represent 20 – 30% of the total population of most 109 third world countries[12]. For Nigeria this translates to an estimated 20 – 30 million children. 110 In some states in southern Nigeria, 80% of the children are in school and can best be reached 111 there for any health care program[13]. 112 target group, which could be screened adequately for early detection of eye diseases and 113 prevention of blindness[14]. Therefore, school children form an important large 114 Not all ocular conditions result in visual impairment. In Pakistan, the prevalence of non- 115 vision-impairing conditions (NVIC) is 14.6%[15]. Although NVIC are non-vision impairing, 116 affected individuals may have need for frequent clinic visit with the attendant impact on their 117 academic performance. Sufferers of allergic conjunctivitis tend to experience quality of life 118 reduction in general health[16]. More worrisome in the rural setting is the potential use of 119 harmful traditional eye medication and improper use of proprietary medications such as 120 steroids for vernal keratoconjuctivitis and the like, which may result in vision impairing 121 complications. 122 There is paucity of data regarding causes of ocular morbidity in children residing in rural 123 communities in Nigeria. This study targets primary school children in a rural community of 124 Anambra state of Nigeria. The aim is to determine the prevalence of ocular disorders and their 125 common causes in order to propose a modality for applying the findings in the prevention of 126 blindness programmes. 127 Abagana is one of the rural communities of Anambra state of Nigeria. It has 8 primary schools 128 with 2,336 pupils and 128 teaching staff. 7 129 There is one community health center and a comprehensive health center of the University of 130 Nigeria Teaching Hospital with only a nurse with ophthalmic training. There is no 131 ophthalmologist or optometrist in the entire community. However, there are 25 consultant 132 ophthalmologists and 10 optometrists practicing at both private and public hospital in the 133 urban city of Enugu about 100 kilometers from rural Abagana. Jones et al[17] observed that 134 following work force and work load issues, financial factors emerge as the biggest threat to 135 rural practice viability. This is same in Nigeria as no financial incentives are currently offered to 136 healthcare personnel working in rural areas. While there is currently no policy in place in 137 Nigeria, several studies[11,18] effectively utilized the teachers for purpose of initial eye 138 screening of school children as a way of solving the personnel shortage challenges. In a study in 139 Tanzania[18], simple screening by teachers correctly identified 80% of the pupils who were 140 found to have bilateral poor eyesight by the eye team, with 91% specificity. Currently in Nigeria 141 school health services provide immunization services through the National immunization 142 scheme, general health education and minimal routine eye screening programme. 143 8 144 Methods 145 146 This was a cross sectional study. After obtaining verbal informed consent from parents and 147 school heads all the available and eligible children in the 8 primary schools in Abagana, aged 6 148 years but below 16 years totaling 2092 were interviewed and examined. 149 The visual acuity was measured outdoors for each child by an ophthalmic assistant using 150 the standard Snellens’ chart placed at 6 meters. When visual acuity was less than 6/9, a pinhole 151 was used to test again. Recorded visual acuities were further crosschecked by the author to 152 ensure validity of findings. 153 Using the Modified WHO/PBL eye examination record, a trained assistant collected the 154 required information on personal data and ophthalmic history. The section on visual 155 assessment and ocular examination were completed by the author. 156 157 The external eye examination was done with the aid of a pen torch and a simple 158 magnifying head loupe. A direct ophthalmoscope was used to examine the posterior segment 159 and where necessary for example if the visual acuity was less than 6/18 and did not improve 160 with pin hole, with no obvious identifiable causative factor, dilated fundoscopy was done using 161 short acting dilating eye drops (0.5% Tropicamide). Ocular alignment was evaluated with 162 corneal reflex text and cover-uncover tests. 163 Refractive error was considered when subnormal visual acuity improved with a pin hole test. 164 Amblyopia was also considered in a child with subnormal visual acuity in the absence of 165 external eye, anterior and posterior segment pathology. 9 166 Children with minor eye problems were treated while those with major eye conditions were 167 referred to the University of Nigeria Teaching Hospital for further evaluation and management. 168 The data were analyzed using the statistical package for social sciences (SPSS-11 IBM, Armonk, 169 New York, USA). Univariate analysis and the parametric method were used to calculate 170 frequency, percentage, and 95% confidence intervals (CI). Comparison of percentages was done 171 using Chi- square test. 172 Ethics approval 173 Ethical clearance for the study was obtained from the Health Research Ethics committee 174 (HREC) of the University of Nigeria Teaching Hospital, Enugu. Study was adequately explained 175 and refusal of participation by the parents, teachers and the children were allowed. 176 10 177 Results 178 Out of 2336 primary school pupils, 2092 aged 6 - 16 years were examined. Out of the 179 244 not examined 62 though eligible were absent from school on the day of visit, while 182 180 were excluded because of ineligibility due to age. More males 1081(51.7%) than females 181 1011(48.3%) constituted the census population giving a male/female ratio of 1.07 to 1. 182 183 In table 1 the 6 - 10 years age group constitutes 52.7% of the subject population 184 Refractive error and corneal scar were the main causes of subnormal vision (Table 2). Bilateral 185 low vision was seen in 6/2092 (0.3%) caused mainly by amblyopia which was diagnosed in 3 out 186 of the 6 children who have low vision. No child was found to be blind according to WHO 187 classification. However, monocular blindness was found in 4/2092 (0.2%) of children. These 188 were due to chorioretinal scars, congenital glaucoma, traumatic cataract and traumatic optic 189 neuropathy respectively and hence contribute 25% each of causes of monocular blindness. 190 Of the 2092 school children seen a total of 6.1 %(CI 0.03-0.13) had ocular disorders of various 191 types (Table3) some occurring bilaterally. Vernal conjunctivitis was the commonest disorder 192 making up 48.0% of all ocular disorders followed by refractive error 11.01% and subconjuctival 193 haemorhage, 7.1%. 194 195 11 196 Discussion 197 198 Most of the children were found to have normal vision in this study. This may be 199 attributed to the absence of environmental factors known to cause blindness in children for 200 example vitamin A deficiency and the positive impact of the sustained rural immunization 201 program against measles by the federal ministry of health. 202 The age group with the lowest number of school children was 14 to 16 years comprising 203 3.7% of the population studied. In a similar study by Oragwu[19], this age group constituted the 204 lowest number of the children studied making up 5.2% of the census population studied. 205 However these numbers are high because this age group ought to be in the secondary school. 206 This could be as a result of the fact that both studies were carried out in rural setting where 207 poverty, ignorance and altered priorities may result in late entry of the children into formal 208 schools. There is slight male preponderance of the total number of children studied. Though 209 there are more females than males at the entry age group level of 6-9 years, more males tends 210 to dominate as age group increased with academic class level. This a reflection of the socio- 211 cultural gender bias of the Igbo tribe that make up the south eastern Nigeria where this study 212 was done[20]. The male gender is preferred and most parents prefer to give education to the 213 male child in the face of limited financial resources. The result is gender inequality of access to 214 formal education and consequent socio-economic limitation of the girl child. Massive education 215 aimed at encouraging the education of the girl child and provision of free education especially 216 in rural areas is highly indicated. 217 12 218 219 220 The 0.5% prevalence of visual impairment found in this study is lower than findings in 221 other studies by Nkanga[21] (0.72%), Yoloye[22] (7.4%), Onyekwe[23] (4.1%), Mohammed 222 (18%)[24]. The different results from the various studies mentioned may be due to the different 223 study areas, different age groups and the definition of visual impairment in each study. 224 Onyekwe combined both primary and secondary school subjects in their study while Yoloye’s 225 definition of visual impairment as visual acuity of 6/9 to 3/60 will tend to produce a higher 226 prevalence of visual impairment when compared with this study. 227 By World Health Organization definition, no case of blindness was found in this study as 228 in a similar study in Ethiopia[24]. In Nkanga”s[12] study, the prevalence of blindness was 229 0.05%. This low prevalence is in keeping with the global low prevalence of blindness in 230 children[25]. Other possible reason for the absence of blind children in this study is the fact that 231 most blind children will be in schools for the blind. Also some of the blind children may be 232 hidden at home as a result of stigma and ignorance of the fact that the child can be helped. 233 However, in this study 4(0.2%) out of the 2092 children examined had visual acuity of 234 <3/60 in one eye, which corresponds to monocular blindness. These were caused by congenital 235 glaucoma, traumatic cataract, optic neuropathy resulting from blunt trauma to the brow, and 236 macular chorioretinal scar, each contributing a case. In Oragwu’s[19] study, 3(0.18%) cases of 237 monocular blindness were due to traumatic cataract, phthisis bulbi and squint. Trauma was 238 responsible for 50% of the cases in this study and 100% of the cases in Oragwu’s[19] study. This 13 239 suggests that simple preventive measures that reduce the occurrence of ocular injuries may 240 significantly reduce the prevalence of monocular blindness in childhood in the area studied. 241 242 This study found ocular disorders to have a prevalence of 6.1%. The prevalence of ocular 243 disorders found in this study is lower than that obtained in the previous studies by Nkanga[12], 244 Yoloye[22], Bhar and Abiose[26]. This may be due to the difference in study areas and the 245 period of study as some ocular disorders have seasonal variability. It may also be a reflection of 246 improved health care delivery over time. 247 The commonest ocular disorders identified were vernal conjunctivitis, followed by 248 refractive error. Refractive error was the commonest in a similar study[12] in Enugu Nigeria, 249 while trachoma ranked the highest in similar studies in Ethiopia[24], and India[27]. This 250 variation may be attributed to the difference in study areas and study population. The 251 Ethiopian and Indian studies were done in trachoma endemic communities. Though vernal 252 conjunctivitis is the major cause of morbidity in this study, it rarely causes visual impairment 253 except in cases of use of harmful traditional eye medication as may be seen in a rural setting in 254 Nigeria. However, in this study refractive was the cause of subnormal vision in 70% of the 255 children presenting with reduced visual acuity. This is slightly higher than that found in a study 256 by Naidoo et al[28] where refractive error accounted for 63.4% of causes of reduced vision in 257 191 eyes. While this study was school based involving 2092 children, the study by Naidoo et al 258 was community based involving a total of 5,599 children. In addition in this study subnormal 259 vision was defined as visual acuity less than 6/9 while Naidoo et al used a visual acuity of less 260 than 6/12 as subnormal vision. This will tend to result in higher number of children with 14 261 subnormal vision in this study. Overall, this underscores the importance of regular eye 262 screening of children as early vision correction is necessary to prevent amblyopia. 263 264 Most of the curable and preventable ocular disorders were due to factors for which 265 interventional programmes could be applied. For instance the monocular blindness from 266 traumatic cataract, is curable surgically (if the lens is the only structure affected) while 267 amblyopia could be prevented by early detection and treatment. This could be made possible 268 by regular vision screening of children, intensive eye health education of children, parents and 269 teachers, and provision of human and infrastructural resources to cater for eye health 270 especially in rural areas. 271 272 A major limitation of this study is its being a school-based study which may not totally reflect 273 the real clinical condition in the community as a significant number of children in the 274 community may not be in school due to poverty. 275 15 276 Conclusion 277 278 This study found a prevalence of 6.1% of ocular disorders amongst the primary school 279 children in Abagana and also showed that most cases of visual impairment are avoidable being 280 either curable or preventable. The commonest cause of visual impairment was amblyopia, 281 which is preventable. Vernal conjuctivities was the commonest ocular disorder found followed 282 by refractive error. None of these contributed to visual impairment. 283 284 Infective disorders did not feature as important causes of ocular morbidity in this area. 285 Since most of the disorders could be attributable to preventable and curable causes, effective 286 preventable measures put in place as well as prompt and appropriate attention to curable 287 causes will drastically reduce ocular morbidity and blindness in children in rural Nigeria. There 288 should be in place a system that encourages eye care workers to work in rural areas with 289 provision of modern facilities to guarantee the viability of rural practice. This will ensure 290 equitable access to quality eye care services which in turn will significantly reduce the burden of 291 eye diseases and blindness among the rural Nigerian children. 292 293 Acknowledgement: 294 The education secretary of Njikoka local government area and the school heads of the 8 295 primary schools in Abagana are hereby thanked for their cooperation and permission to 296 undertake this study. Many thanks to the Federal Ministry of Health Nigeria which funded this 297 research through the management of University of Nigeria Teaching Hospital, Enugu. 16 298 299 300 References 1. Gilbert C. Childhood blindness in the context of vision 2020. The Right to sight. Bulletin WHO 2004; 79:227-232. 301 302 303 2. Gilbert C. New issues in childhood Blindness. Community Eye Health Journal, 2001 ; (14) 40: 53 – 56. 304 305 306 3. Community Eye Health Journal 1999; 12 (31):44-45. 307 308 David Y. The Global Initiative VISION 2020: The Right to sight. Childhood Blindness. 4. Gilbert C. Changing challenges in the control of blindness in children. Eye, 2007; 21(10): 1338-1343. 309 310 311 5. WHO, Geneva. Global Initiative for the Elimination of Avoidable Blindness. Geneva. WHO/PBL/97. 312 313 314 6. Gilbert C, Foster A. Childhood blindness in the context of Vision 2020: The Right to sight. Bulletin WHO 2001; 79;227-232 315 316 317 318 319 7. Shamanna B, Muralikrishnan R. Childhood cataract: Magnitude, management, Economics and Impact. Communit Eye Health Journal 2004, (17) 50: 17 – 18. 17 320 8. Fazzi E, Signorini S, Bova S, Ondei P, Bianchi PE. Early intervention in visually impaired children. International congress series 2005; 1282: 117 – 121. 321 322 323 9. 324 10. Khandekar RB, Abdu-Helmi S. Magnitude and determinats of refractive error in Oman school children. Saudi Medical Journal 2004; 25: 1388-1393. 325 326 Ottar-Pfeifer W. Insight 2005 Apr – Jun, 30(2): 17-20. 11. Qamar AR. Eye screening in school children: A rapid way. Pakistan Journal of Ophthalmology 2006;22(2):79-81 327 328 329 12. Nkanga D.N. Dolin P. School Vision Screening programme in Enugu, Nigeria: 330 Assessment of referral criteria for error of refraction. 331 Ophthalmology. 1997; 5(I): 34 – 40. Nigerian journal of 332 333 13. Abubakar S, Ajaiyeoba A.I Screening for Eye disease in Nigerian school children. Nigerian journal of Ophthalmology: 2000; 9(1): 6-9. 334 335 336 337 14. Desai S, Desai R, Desai N, Lohiya S. School eye health appraisal. Indian Journal of Ophthalmology, 1989 ; 37(4): 173-175. 338 339 15. Hussain A, Awam H, khan MD. Prevalence of non-vision impairing condition in a village 340 in Chekwal district, Punjab, Pakistan. Ophthalmic epidemiology. 2004; 11(5): 413- 341 426. 18 342 343 16. Smith A, Rodruiguez A, Alio J, Marti N, Teus M, Guillen S, Bavenes J. The economic and 344 quality of life impact of seasonal allergic conjuctivities in a Spanish setting. 345 Strabismus, 2000;8(4):283-285. 346 17. Jones JA, Humphreys JS, Adena MA. Doctors’ perspectives on the viability of rural 347 practice. 348 http://www.rrh.org.au 349 18. Rural and Remote Health 4:305. (On line) 2004. Available: Wedner SH, Ross DA, Balira R, Kaji L, Foster A. Prevalence of eye diseases in primary 350 school children in a rural area of Tanzania. British Journal of Ophthalmology 351 2000;84:1291-1297. 352 353 19. Oragwu UCI. Survey of Eye Health Status of Primary School children in Nkanu West 354 local Government Area of Enugu State of Nigeria. Dissertation for the award of a 355 fellowship diploma of National Postgraduate Medical College in Ophthalmology 356 2002. 357 20. Ndu AC, Uzuchukwu BSC. Child gender preference in an urban and rural community in Enugu, Eastern Nigeria. Journal of College of Medicine 2011; 16(1):24-29. 358 359 360 361 362 21. Nkanga DG, Dolin P. Blindness and visual impairment in primary school children in Enugu State, Nigeria. East African Medical Journal 1998,75(8);478-481. 19 363 22. Yoloye MO: Patterns of visual defects and eye disease among primary school 364 children in Ibadan. Dissertation for award of a fellowship diploma of the National 365 Postgraduate Medical College in Ophthalmology 1990 366 367 23. Onyekwe LO, Ajaiyeoba AI, Malu K.N. Visual impairment amongst school-children and 368 adolescents in Jos, Nigeria. Nigerian Jornal of Ophthalmology. 1998; 6(1); 1-5 369 370 24. Mohammed S, Abebe B. Common eye diseases in children of rural community in Goro 371 district, Central Ethiopia. Ethiopian Journal of Health Development.2005; 19(2):148- 372 152. 373 374 25. Foster A: World wide blindness increasing but avoidable. Seminars in Ophthalmology 1993; 8: 166 – 170. 375 376 377 26. Abiose A. Bhar L S. The ocular health status of Post Primary Schools in Kaduna. Journal of Paediatric Ophthalmology and strabismus. 1980; 17:337- 340. 378 379 380 27. Nazia U, Santhosh K, Khaja BM, Mohammed AZ, Reddy DV. A comparative clinical 381 survey of the prevalence of refractive errors and eye diseases in urban and rural 382 school children. Canadian Journal of Ophthalmology 2009; 44:328-333 20 383 28. Naidoo KS, Ragbunandan A, Mashige PK, Govender P, Holden BA, Pokharel GP et al. 384 Refractive error and visual impairment in African Children in South Africa. 385 Investigative Ophthalmology and Visual Sciences 2003;44(9): 3764-3770. 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 21 405 406 Table 1. Age and Sex Distribution of the study subject (n=2092) Age group(years) Sex Male 500 533 48 1081 6-9 10-13 14-16 Total Total Female 600 382 29 1011 1100 915 77 2092 407 408 409 410 411 412 413 414 (n = 2092) 700 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 Number of pupils 600 Male 500 Female 400 300 200 100 0 6 to 9 10 to 13 14 to 16 22 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 Table 2 Causes of bilateral subnormal, low vision and unilateral blindness among school children aged 6-16 years old. Causes Subnormal vision Visual Unilateral % Total cases (%) (VA <6/9-6/18) impairment(VA blindness(VA<3/60) (n=2092) <6/18->3/60) Refractive error 14(70%) 14 (0.7%) Corneal scar 3(15%) 3 (0.1%) Amblyopia 3(15%) 3 (50%) 6 (0.3%) Macular scar 1 (16.7%) 1 (25%) 2 (0.1%) Albinism 1 (16.7%) 1 (0.05%) Congenital glaucoma 1 (16.7%) 1 (25%) 2 (0.1%) Traumatic cataract 1 (25%) 1 (0.05%) Traumatic Optic 1 (25%) 1 (0.05%) neuropathy Total 20 (100%) 6 (100%) 4 (100%) 27 (1.5%) 23 467 Table 3 Distribution of ocular disorders (n = 127) Age Total (%) 6 – 9(%) 10 –13(%) 27 (21.3) 31 (24.4) 3 (2.4) 61(48.1) Refractive error 6(4.7) 6(4.7) 2(1.5) 14(11.0) Subconjunctival haemorrhage 7(5.6) 2(1.5) - 9(7.1) Amblyopia 5(3.9) 1(0.8) 2(1.5) 8(6.2) Hordeolum externa 1(0.8) 5(3.9) - 6(4.7) Miscellaneous 4(3.1) 1(0.8) - 5(3.9) 8(6.2) 15(11.8) 1(0.8) 24(18.9) 58(45.8) 61(48) 8(6.2) 127(100) Ocular disorders Vernal conjunctivitis 14 -16(% Ptosis Total 468 469 470