The Prevalence of Five Major Causes of Low Vision in Ahmedabad

Population and their Respective Management with Residual Visual

Function

ByDadhija Paritoshbhai Dave

Study Project for B.Optometry

AIM

• The Prevalence of Five Major Causes of Low Vision in Ahmedabad Population and their Respective Management with Residual Visual Function

REVIEW OF LITERATURE• S.A.Khan concluded that the main causes for Low Vision are

Retinitis Pigmentosa , Diabetic Retinopathy , Macular Diseases and Myopic Degeneration. This study was carried out in Tertiary Eye Care Hospitals of South India8

• As per Dandona R , the most frequent causes of Low Vision included Retinal Diseases , Amblyopia , Optic Atrophy , Glaucoma and Corneal Diseases in the southern part of India (Andhra Pradesh)9

• HB Thapa , S.Gurung , A.Sherchan , AS Karthikeyan and RP Kandel described in their study the leading causes are Lens Related Causes (Aphakia/Pseudophakia/Cataract) , Refractive Errors , Amblyopia , All Globe Abnormalities , Corneal Pathology , Retinal Diseases (Different Maculopathies ,Retinal scars , Retinal Hemorrhages , Vein Occlusion) and Other causes (Albinism , Nystagmus , Different Associated Syndromes) in Nepal Population10

MATERIAL AND METHODOLOGY• A prospective study was done to determine the Causes of Low Vision and

its Management in Ahmedabad City. Patients were conducted, at “BLIND SCHOOL”, Vastrapur, and “Nagari Eye Hospital”, Ellisbridge, Ahmedabad. Total of 350 Patients falling in Inclusion Criteria were examined

Inclusion criteria:• Patient falling in criteria of Low Vision Definition that is Better Eye seeing

≤ 6/18 to Perception of light after refraction and surgical correction• Patient with Other Physical and Mental Disability like Deaf , Intellectual

Disable etc

Exclusion criteria:• Patient not falling in criteria of Low Vision (Normal Patients)• Patient those are totally Blind or having no perception of light

METHODOLOGYHistory and Eye Examination• External eye examination• Anterior segment examination by torch and/or slit lamp biomicroscope• Fundus examination by direct and/or indirect ophthalmoscopeVisual Acuity• Distant visual acuity was assessed with Distance Snellen chart.• Near vision was assessed by N series near chart of continuous text.• Patients with visual acuity equal/less than 6/18 to perception of light in the

better eye, underwent tests for refraction and managementRefraction• Objective Refraction – Retinoscope.• Subjective Refraction – Trial Frame , Full Aperture Trial lenses • Patient were assessed using the optimal illumination of a 40 watt halogen

lamp, with the light source directed at an angle of 45° to the page, minimizing glare for near .As per subjective refraction spectacles were advised

Cont….Color Vision• Panel D-15 (Binocularly)Contrast Sensitivity• Peli Robson ChartVisual Field• Amslers Grid• Confrontation TestLow Vision Aids Optical Devices• For Distance – Telescopes• For Near – Different Magnifiers (Spectacle Magnifier , Stand

Magnifier , Bar Magnifier , Dome Magnifier , Hand Held Magnifier and Illuminated Stand Magnifier ) were tried with patients having less vision

Non-Optical Devices• Large Print Books, Bold Line Notebook , Felt tip pen ,

Typoscopes , Reading lamp , Reading Stand , Peaked Caps , Torch were advised.

Training• Orientation and Mobility Training, Rehabilitation Training

and Tactile Training. Braille and Talkative Instruments were advised to them.

• The Data Collected from the study was inputed in Excel Sheet and analysis was made with calculations to find out 5 major causes of Low Vision in Ahmedabad Population

RESULT

Other Causes founded in 19.44% were Aphakia , Pseudophakia , Cataract , Refractive Error associated with Amblyopia , Macular Dystrophy, Diabetic Retinopathy, Glaucoma, Retinopathy of Prematurity and Retinal Detachment

LOW VISION AIDS AIDS PATIENTS PERCENTAGE CAUSES DEVICES

Only Training 115 32.86% Advanced RP , Retinal Dystrophy , Severe Optic Atrophy , ARMD

Training Advise like Orientation and Mobility , Rehabilitation and Tactile Training.Along with it Braille and Talkative Instruments were advised.

Near Devices 86 24.57% Microcornea , Microophthalmos,Iris Coloboma , Retinal Coloboma with Nystagmus , High Hypermetropia

Spectacle Magnifier , Stand Magnifier , Bar Magnifier , Dome Magnifier , Hand Held Magnifier and Illuminated Stand Magnifier

Distance Devices

57 16.29% Myopic Degeneration , High Myopia

Telescopes

Near and Distance Devices

27 7.71% RP , Microcornea , Microophthalmos,Iris Coloboma,Retinal Coloboma with Nystagmus, Glaucoma , Albinism , Macular Dystrophy , Diabetic Retinopathy , Aphakia , Pseudoaphakia , Cataract

Spectacle Magnifier , Stand Magnifier , Bar Magnifier , Dome Magnifier , Hand Held Magnifier and Illuminated Stand Magnifier,Telescopes

Refraction + High Add

65 18.57% Refractive Error , Amblyopia , Aphakia , Pseudophakia , Cataract

Spectacle for Near and Distance Correction

Total 350 100%

DISCUSSIONThis study presents five major causes of Low Vision in Ahmedabad

Population.According to this study which was carried out in 350 Patients , 248 Patients (70.86%) were males.The major causes in Ahmedabad Population are :

• Microcornea , Microphthalmos, Retinal Coloboma and Nystagmus - 22.57%

• Optic Atrophy - 19.42%• Retinitis Pigmentosa – 17.43%• Myopic Degeneration – 14.85%• Albinism – 6.29%• Others – 19.44% (Aphakia , Pseudophakia , Cataract , Refractive Error

associated with Amblyopia , Macular Dystrophy, Diabetic Retinopathy, Glaucoma, Retinopathy of Prematurity and Retinal Detachment)

.

According to the study done by Mr.S.A.Khan in 450 Patients in Southern India , the leading causes were :

• Retinitis Pigmentosa – 19% , • Diabetic Retinopathy – 13% , • Macular Diseases – 17.7% , • Myopic Degeneration – 9%.• Out of 450 Patients , 297 (72%) were males

As per study of Mr.S.A.Khan , 72% of Patients were males. Similarly in this study the maximum patients that is 70.86% were males.

According to study of Mr.S.A Khan , Retinitis Pigmentosa was major cause with 19% where as in this study Retinitis Pigmentosa was third major cause with 17.43%.

As per study of Mr.S.A.Khan Myopic Degeneration was the fourth major cause in Southern India same as Myopic Degeneration is the fourth Major Cause in the Ahmedabad Population

But Diabetic Retionpathy and Macular Diseases are not the major causes in Ahmedabad Population where as they were one of the major causes in southern India as per study of Mr.S.A.Khan

According to study of Dandona R., the study which was carried out in Southern part of India that is Andhra Pradesh ,

• Retinal Diseases was major cause with 35.20% , followed by • Refractive Errors & Amblyopia – 25.70% , • Optic Atrophy – 14.30% , • Glaucoma – 11.04% , • Corneal Diseases – 8.60%.

This study was performed on 144 Patients. Relating this study to our , we found that the Optic Atrophy which was third major causes in Andhra

Pradesh which constituted to 14.30% , was the Second major cause in Ahmedabad Population with 19.42%.

R.Dandona studied that 11.04% people of Andhra Pradesh were having Glaucoma as there Low Vision Disorder which contributed to fourth major cause.However in this study , Glaucoma was not found to major cause of Low Vision.

Similarly Refractive Error and Amblyopia were not the major causes in Ahmedabad Population.

Microcornea which is one of the Corneal Dystrophy , associated with Microphthalmia , Retinal Coloboma and Nystagmus was the most leading cause in Ahmedabad Population.In Study of Dandona R different types of Corneal Diseases formed 8.60%.

HB Thapa , S.Gurung , A.Sherchan , AS Karthikeyan and RP Kandel studied that the leading causes of Low Vision were :

• Lens Related Causes (Aphakia / Pseudoaphakia / Cataract ) – 35.55% , followed by• Refractive Error and Amblyopia – 19.23% , • Retinitis Pigmentosa – 10.84% , • Whole Globe Abnormalities – 10.24% , • Corneal Pathologies – 7.24% , • Retinal Diseases – 6.64% and Others – 10.25% (Albinism , Nystagmus and Associated Different

Syndromes).

This study was carried out in 166 Nepali Patients.Out of these , 70% of Patients were malesAccording to our study , 70.86% Patients were males out of 350 patients which is similar to study of HB Thapa

and group which has 70% Patients as males.

In study of HB Thapa and Group Lens Related Causes was major cause with 35.55% whereas in Ahmedabad Population that is not the Major Cause.Similarly in study by Dandona R and S.A.Khan , Lens Related Causes were not Major Causes.

Refractive Error contributes to second major cause in Nepal with 19.23% but in Ahmedabad Population it was not major cause.

Retitinis Pigmentosa was third major cause with 10.84% in Nepal.Similarly in Ahmedabad Population it was third major cause with 17.43%.However in study of Mr.S.A.Khan , Retinitis Pigmentosa was the most major cause with 19%.

Corneal Pathologies contributed to fifth major cause in Nepal Population with 7.24%.Similarly in study of Dandona R , Corneal Diseases was fifth major cause with 8.60%.However in Ahmedabad Population Microcornea which is one of the Corneal Dystrophy , associated with Microphthalmia , Retinal Coloboma and Nystagmus was the most leading cause with 22.57% in Ahmedabad Population.

Albinism was found in very less people in Nepal as reason for causing low vision but in Ahmedabad Population it is the fifth leading cause of Low Vision with 6.29%

As per study by HB Thapa , S.Gurung , A.Sherchan , AS Karthikeyan and RP Kandel , Training was advised in 6.02% Patients , Near Magnification was given in 54.23% Patients , Spectacles as per Refraction were advised in 19.27% Patients , Distance Devices were given in 20.48% Patients.However, as per our study Training was advised in 32.86% Patients, Near Magnification was given in 24.57% Patients, Spectacles as per Refraction were advised in 18.57% Patients, Distance Devices were given in 16.29% Patients and Near and Distance Devices were advised in 7.71%.

This shows that severity of Low Vision was more in Ahmedabad Population as compared to Nepal Population

• There are so many studies done on different causes of Low Vision in the different regions of the world , but in Ahmedabad Population not a single study was done. So this study is about the leading five major causes of Low Vision in Ahmedabad Population

CONCLUSION

By this study we conclude the Five Major Causes of Low Vision in Ahmedabad Population and their respective management gives better lifestyle to low vision patient with their residual visual function.

REFRENCES1. World Health Organization. Global initiative for the elimination of avoidable blindness.

WHO/PBL/97.61. Geneva: WHO, 1997.

2. International Classification of Diseases ICD -10 2010;2 3. World Health Organization 1997

http://www.who.int/blindness/causes/priority/en/index5.html

4. A.K.Khurana Comprehensive Ophthalmology Fourth Edition

5. World Health Organization 2006 , Retrived December 16 2006 http://en.wikipedia.org/wiki/Blindness

6. World Health Organization Fact Sheet Number 282 June 2012 http://www.who.int/mediacentre/factsheets/fs282/en/

7. AO Oduntan Prevalence and Causes of Low Vision Worldwide S Afr Optom 2005;64:44-54

8. S.A.Khan To obtain data on the characteristics and causes of low-vision patients seen at a tertiary eye care hospital in India. Indian Journal of Ophthalmology 2000;48:201-207

9. Dandona R, Dandona L, Srinivas M, Giridhar P, Nutheti R, Rao GN .To assess the prevalence and causes of low vision in a population in southern India for planning low vision services. International Centre for Advancement of Rural Eye Care, L. V. Prasad Eye Institute, Hyderabad, India http://www.ncbi.nlm.nih.gov/pubmed/12359608

10. HB Thapa, S Gurung, A Sherchan, AS Karthikeyan, RP Kandel Hospital based study on causes of low vision and patient preference for different types of low vision devices Journal of Institute of Medicine 2007;29:2

11. Shah SP, Minto H, Jadoon Z, on behalf of the Pakistan National Eye Survey Study Groupet al. Prevalence and causes of functional low vision and implications for services: The Pakistan National Blindness and Visual Impairment Survey. Invest Ophthalmol Vis Sci. 2008;49:887–893.

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APPENDIXPATIENT PROFORMA

• DATE: _____/______/_______ • NAME OF PATIENT:

• ADDRESS:

• AGE: ____________ GENDER: __________________

• COMPLAIN: ________________________________________________________________ • HISTORY: __________________________________________________________________ • History of Eye Surgery:

____________________________________________________________________________ • History of Systemic illness:

____________________________________________________________________________

• Cause / Duration of Low Vision / Blindness: ____________________________________________________________________________

• Other Disability: ____________________________________________________________________________

• Family History: _______________________________________________________________

• Medical History: ______________________________________________________________

• Education: ___________________________________________________________________

• Financial Status: Sufficient / Non-Sufficient

• Use of glasses: Yes / No

Previous Glass Prescription Sph cyl axis VA• RE:• LE: • Previous Low Vision care: Yes / No

• Source of Low Vision Device: Prescribed / Self Purchased

• Low Vision Device: Local / Imported

• Currently being used: Yes / No

• If Yes then details of it: ________________________________________________________

• Distance Inspection: ___________________________________________________________ • External Examination: RE LE • Lids / Lacrimal Apparatus:• Conjunctiva:• Cornea:• Anterior Chamber:• Iris / Pupil:• Lens:• Cover Test:• Ocular Movement:• Fundus Evaluation:• Literacy: Print / Braille / Print + Braille / Not literate• Fixation: OD: Central / Eccentric• OS: Central / Eccentric

Unaided Vision : • Sph cyl axis VA • RE:• LE: Pinhole Vision: • • RE:• LE:

Objective Refraction: (Retinoscopy)• Sph cyl axis VA • RE:• LE: • Subjective correction with Visual Acuity:• Sph cyl axis VA• RE:• LE:• BE:

• Near Vision : Test used _________________________________________________________

• Unaided Near Visual Acuity:

• RE: N• LE: N• BE: N

• Aided Near Visual Acuity: • RE: N• LE: N

• At ____________ Working Distance

• With BE ___________________ N _____________ Working Distance

• Low Vision Device for Distance

• Telescope : _____ X

• Visual Acuity with Telescope • RE: _______• LE: _______

• Not Tried :

• Low Vision Device for Near:

• Magnifier: Prescribed / Not• Type: With ____ D

• Visual Acuity _____ in reduced Snellen N Notation

• Combination of 2 Devices for Near : ______________________________________________________________________

• Reading Speed with Low Vision Device: ______________________________________________

• Additional Illumination: Required / Not Required

• With Additional Illumination: Improved / Remain Same / Facing Difficulty

• Binocular Vision : Yes / No

• Visual Field : Done / Not Done

• Limitation of Visual Field : • RE:• LE:

• Contrast Sensitivity : ____________________________________________________________

• Test used _____________________________________________________________________

• Glare / Photophobia : Yes / No

• In Sunlight : No Problem / Uncomfortable / Can Hardly Seen

• Preferred Indoor light: Normal / Extralight / Reduced

• Orientation and Mobility Problem : Yes / No

• When : In Daytime / At night

• Colour vision : ______________________________________________________

• Non-Optical Devices : _______________________________________________________

• Rehabilitation Service or Training Required : Yes / No

• Advise: ______________________________________________________

• Follow up Date: ________________