According to a report by the International Agency for the Prevention and Treatment of Blindness’s Vision Atlas there are 43 million blind and 295 million with visual impairment in the world. Unfortunately, out of these, a huge 77% was found to be completely preventable or treatable. In India alone there are estimated to be 4.95 million blind with another 70 million visually impaired.1And a huge 82.3% of this blindness among adults and 35% in children has been found to be due to avoidable causes.2 This clearly states that there is an alarming proportion of blind or visually impaired due to avoidable causes which needs to be addressed to. A disability is any condition of the body or mind (impairment) that makes it more difficult for the person with the condition to do certain activities (activity limitation) and interact with the world around them (participation restrictions).3 Disability is part of being human and is integral to the human experience. It results from the interaction between health conditions such as dementia, blindness or spinal cord injury, and a range of environmental and personal factors. An estimated 1.3 billion people – or 16% of the global population – experience a significant disability today.4 Visual disability certificate is issued in India for visually impaired and blind, which is categorized as per the Gazette of India Extraordinary, 2001, given by a sub- committee constituted by the Ministry of Social Justice and Empowerment.5 UDID (Unique Disability Identity Card) sub scheme has been implemented with a view of creating a National Database for Persons with Disabilities across the country. Under the UDID project, certificates of disability and Unique Disability Identity Cards are issued to Persons with Disabilities through competent medical authorities notified by respective State Governments/Union Territories.6 These visual disability certificates which are a part of the rehabilitative service to the blind or visually impaired can serve as an important source of causes and severity of visual handicap, for the people presenting for the same if not representative of the entire population in general. These causes when analyzed will help us categorize them into avoidable (preventable or treatable) or non-avoidable. The avoidable causes can then be studied in detail and can help us formulate policies which in future can prevent this kind of visual impairment or blindness occurring in the first place, either by methods of prevention or prompt management. With this background the present study was designed to find out the various causes of visual impairment through the disability certificates issued at a District Hospital level. The analyzed data was then used to categorize the causes into avoidable (preventable or treatable) or non-avoidable causes for visual impairment and blindness.

The data of patients who were issued disability certificate at Zonal Hospital, Shimla from 1 April 2023 to 31 March 2024 via the Unique Disability Identification Database Portal was collected retrospectively and analyzed to study the various causes and severity of ocular disability. Here is the table issued by Government of India (MOHFW) for percentage disability to be issued according to the BCVA.7 A total of 100 patients were issued the UDID card. Their age, sex, vision in both eyes and disability percentage was retrieved and compiled on Excel sheet. The percentage of disability had been categorized as per the recent guidelines issued by the Gazette of India, Ministry of Health and Family welfare.8 The disability had been categorized as temporary or permanent, also classifying the handicap as mild, moderate, severe, or profound. The collected data was then analyzed to find out avoidable (preventable or treatable) or non-avoidable causes of visual disability. The data was collected in accordance with the declaration of Helsinki. As the data was collected from records and involved no direct patient interaction and the names of the patients were not recorded to protect anonymity, permission from the Ethical Committee was not required.

Distribution of patients according to age The age group of the patients varied from 2-99 years with the mean age being 41.9 years. Maximum patients, who were issued medical certificate were found to be in the age group of 40-60 years (33%) Out of 100 patients there were 65 males and 35 females with a male female ratio of 1.85 to 1. Table 1: Distribution of males and females according to age groups Age (in yrs) Males Females TOTAL 0-20 12 6 18 20-40 22 8 30 40-60 18 15 33 60-80 12 6 18 >80 1 1 Total 100 Profile of patients on the basis of percentage disability The visual acuity was categorized as shown below (as per the guidelines issued by Government of India MOHFW).6 Majority of patients had 40% disability (45%) Patients with profound visual disability were only 14%. Table 2: Profile of patients based on percentage disability S. No. Vision in Better eye Vision in Worst eye Disability Percentage Disability Grade Number of Patients Percentage of Patients 1 6/6 to 6/18 6/6 to 6/18 0 0 0 0% 6/24 to 6/60 10 0 0 0% <6 l60 to 3/60 20 I 0 0% <3/60 to no light perception 30 1 1% 2 6/24 to 6/60 6/24 to 6/60 40 III a 45 45% <6/60 to 3/60 50 III b 6 6% <3/60 to no light perception 60 IIIc 32 32% 3 <6/60 to 3/60 <6/60 to 3/60 70 III d 1 1% <3/60 to no light perception 80 III e 1 1% 4 <3/60 to 1/60 <3/60 to no light perception 90 IV a 6 6% 5 Only HMCF Or light perception No light perception Only HMCF Or light perception No light perception 100 IV b 8 8% Profile of patients based on low vision and blindness Majority of patients 84% were classified as low vision (Visual disability 40-80%). 15% were categorized as Blind (Visual disability 90-100%) Distribution of applicants according to cause Most common cause came out to be pathological myopia 26% followed by amblyopia 20% and trauma 15%. Glaucoma accounts for profound visual disability (80-90%) in 10% of individuals. S. No. CAUSE No. of patients 1. PATHOLOGICAL MYOPIA 26 (26%) 2. AMBLYOPIA 20 (20%) 3. PTHISIS BULBI 15 (15%) 4. CORNEAL CAUSES 12 (12%) 5. GLAUCOMA 10 (10%) 6. CONGENITAL CAUSES 9 (9%) 7. RETINAL DISORDERS 8 (8%) TOTAL 100

Severe visual impairment and blindness is a worldwide problem which has a significant socioeconomic impact. Around two-third of causes of blindness are avoidable. There have been many surveys in India and abroad regarding prevalence of blindness in the community. Unique Disability Identification card (UDID) has been created for a unified database at the national level for people with disability certification. The disability certificates issued to people with visual disability offer a lot of benefits like travel concessions, income tax benefits, disability allowances and reservation in jobs and colleges. In addition, they serve as an important source of information regarding the causes of blindness. Our study was done at Zonal hospital, Shimla over 100 applicants from April 2023 to March 2024 with an aim to study mostly the avoidable causes of blindness which in future could help when planning preventive strategies in addition to emphasis on prompt management. In our study it was found that there were more male applicants over females which can be attributed to the fact that of their traditional role of bread earners and more mobility in our society, and hence, more need for employment and other benefits. This gender bias was observed in other Indian studies such as that conducted by Ambastha et al in Bihar,9 Gosh et al in west Bengal10 and Joshi et al in central India.11 In our study age ranged 2-99 years, maximum applicants were in the range 40-60 years. The mean age was 41.9years. Patients in the age 20-60 years were significantly more as compared to above 60 and less than 20 years. This is because the benefits can be easily availed by people in this age group like free bus passes, income tax concessions, professional college admission and job reservations. This suggests that the driving force behind getting disability certification was more among the working age group. Another study conducted by RC Khanna et al the mean age was 35.5 years which is in consonance with our study. Amblyopia was also the major cause of blindness among 40-60years age group in a study conducted by Anita Ambastha et al.9 In our study the primary cause of visual disability was pathological myopia (26%), followed by amblyopia (20%). It suggests that screening of children in schools should be strengthened to detect refractive errors at the earliest and effective measures should be taken to prevent amblyopia which can be easily treated if detected early. Trauma leading to phthisis bulbi (15%) was the next important cause of blindness leading to visual disability. Early and efficient management of trauma by trained ophthalmologist at secondary and tertiary level can improve the prognosis. The next important cause was corneal blindness accounting for 12% of patients. Corneal injuries can be prevented by health education and by preventing occupational hazards. Corneal transplant can be encouraged by setting up more eye banks & eye donation centers. Promotion of eye donation can be encouraged by IEC activities, Special certificate of appreciation to persons who have pledged for eye donation and family members of eye donors should be given certificate of appreciation & commemorative medals to encourage other individuals as well. Glaucoma, was another important cause of irreversible blindness in our state which can be attributed to the fact that the awareness about eye diseases is still inadequate. Early diagnosis and treatment can prevent this dreaded cause of blindness. In advancing world, where all kind of treatment options are available, people of our state are suffering from profound visual loss due to glaucoma due to diagnosis in advanced stage. Starting from screening of all patients aged > 40, monitoring of IOP, family history, strict adherence to medications is the key to prevent progression of glaucoma. Congenital causes account for 9% of all causes out of which retinitis pigmentosa was the most important cause. This could be related to lack of genetic counselling and consanguinity in the area. A study done on RP patients in various states of India has shown an autosomal-recessive, predominant inheritance pattern, and more than 92% of cases in autosomal-recessive category had positive history of consanguinity12. Low vision aids can be given to needy patients. Retinal disorders account for only 8% of total causes out of which, Diabetic retinopathy was the most important cause. A fundus evaluation at regular intervals of all diabetic patients should be mandated to avoid this preventable cause of blindness. Facilities for diagnosis and management are present but the demographic and social factors could contribute to the delayed diagnosis of the condition. Regular eye check-up camps can be beneficial for early and prompt diagnosis and timely intervention. An overview of all the causes, suggests that majority (61%) of the causes were avoidable (either preventable or treatable). The importance of early diagnosis and treatment needs to be emphasized further to prevent blindness from avoidable causes like refractive errors, amblyopia, glaucomatous optic atrophy and diabetic retinopathy. LIMITATION The limitation of the present study was that it was a hospital-based study and not all needy of the disability certificate are not able to come to the hospital so the results cannot be generalized to the whole community.

The fact that refractive error and amblyopia account for the majority of the blindness burden in our state suggest that proper counseling, regular screening of eyes right from birth, and prompt management is the key to prevention of unnecessary blindness. Improving awareness regarding ocular trauma so as to reduce corneal scarring or phthisis is another milestone yet to be achieved. In addition, eye bank services need to be improved. Routine regular screening for forestalling treatable blindness conditions such as glaucomatous optic atrophy and diabetic retinopathy needs emphasis. For all of this to happen this our ophthalmic services need to be strengthened from the grass root level with co-operation of health care workers, refractionists and medical officers and not only ophthalmologists.

1. Orbis International. New global blindness data [Internet]. 2021 [cited 2025 May 1]. Available from: https://www.orbis.org/en/news/2021/new-global-blindness-data 2. Ministry of Social Justice and Empowerment. Guidelines for evaluation of various disabilities and procedure for certification: Notification dated 1st June, 2001. The Gazette of India Extraordinary. Part 1, Section 1, No. 154 [Internet]. [cited 2008 Nov 27]. Available from: http://www.ccdisabilities.nic.in/eval2/page6.htm 3. World Health Organization. International classification of functioning, disability and health (ICF). Geneva: WHO; 2001 [cited 2025 May 1]. 4. World Health Organization. WHO official website [Internet]. [cited 2025 May 1]. Available from: https://www.who.int. 5. Brennan ME, Knox EG. An investigation into the purposes, accuracy, and effective uses of the Blind Register in England. Br J Prev Soc Med. 1973;27(3):154–9. 6. Ministry of Law and Justice (Legislative Department), Government of India. The Rights of Persons with Disabilities Act, 2016. New Delhi: Government of India; 2016 [cited 2019 Mar 10]. Available from: http://www.disabilityaffairs.gov.in/upload/uploadfiles/files/RPWD%20ACT%202016 7. Ministry of Social Justice and Empowerment. Guidelines for evaluation of various disabilities and procedure for certification [Internet]. [cited 2025 May 1]. Available from: http://disabilityaffairs.gov.in/content/page/guidelines 8. Unique Disability ID (UDID). Know more about UDID [Internet]. [cited 2025 May 1]. Available from: https://www.swavlambancard.gov.in/know-more-about-udid 9. Ambastha A, Kusumesh R, Sinha S, Sinha BP, Bhasker G. Causes of visual impairment in applications for blindness certificates in a tertiary center of Bihar and its role in health planning. Indian J Ophthalmol. 2019 Feb;67(2):204–8. doi: 10.4103/ijo.IJO_837_18. PMID: 30672470; PMCID: PMC6376837. 10. Ghosh S, Mukhopadhyay S, Sarkar K. Evaluation of registered visually disabled individuals in a district of West Bengal, India. Indian J Community Med. 2008;33(3):168–71. 11. Joshi RS. Causes of visual handicap amongst patients attending outpatient department of a medical college for visual handicap certification in central India. J Clin Ophthalmol Res. 2013;1(1):17–9. 12. Vinchurkar MS, Sathye SM, Dikshit M. Retinitis pigmentosa genetics: A study in Indian population. Indian J Ophthalmol. 1996;44:77–82.