National Blindness & Visual Impairment Survey 2015-2019
West Delhi (Delhi)

Cataract surgery- Coverage, Outcomes and Barriers

Cataract surgical coverage among people with pin hole visual acuity < 3/60, <6/60 and <6/18 were 97%, 94.7% and 84.4% respectively. However cataract surgical coverage among eyes having cataract and pin hole visual acuity as < 3/60, <6/60 and <6/18 were 88.9%, 84.7% and 70.1% respectively.

Most of cataract surgeries in West Delhi, Delhi 94.9% were surgeries with intra-ocular lens implantation.

Majority visual outcome after cataract surgery were very good, 62.6% people had presenting visual acuity >6/12 in operated eye. However 23.3% had visual acuity <6/18 in operated eye and 10.5% had PVA < 6/60. Among those whose visual acuity was better than 6/60, the most important cause was Uncorrected refractive error 42.6%. Those patients whose post-operative PVA < 6/60, the most important cause was existing pre-operative Surgical complications 40.4% Other causes of poor outcomes were Ocular comorbidity 36.2%.

Out of all people having bilateral pinhole visual acuity <3/60 due to cataract, in people aged ≥ 50 years most important barriers for cataract surgery were Fear (38.5%), Cost (23.1%), Treatment denied by provider (15.4%) and Need not felt (15.3%).

Definition of various categories of visual impairment
Blindness

Presenting visual acuity < 3/60 in better eye

Severe Visual Impairment (SVI)

Presenting visual acuity < 6/60 – 3/60 in better eye

Moderate Visual Impairment (MVI)

Presenting visual acuity < 6/18 – 6/60 in better eye

Early Visual Impairment (EVI)

Presenting visual acuity < 6/12 – 6/18 in better eye

Moderate Severe Visual Impairment (MSVI)

Presenting visual acuity <6/18-3/60 in better eye

Visual Impairment

Presenting visual acuity < 6/18 in better eye

Functional Low Vision

A person with impairment of visual functioning even after treatment and/or standard refractive correction, and a visual acuity of less than 6/18 to light perception, or a visual field of less than 10 degree from the point of fixation.

Cataract Surgical Coverage (Person) indicates how many persons received cataract surgery (one or both eyes) among all who were bilaterally pinhole blind due to cataract.
The numerator includes persons with one operated and one pinhole blind eye and persons with bilateral (pseudo) aphakia. The denominator includes the numerator, plus persons bilaterally pinhole blind due to cataract. Besides this, the indicator can also be calculated separately for PinVA <6/60 and <6/18.

Cataract Surgical Coverage (Eye) measures the proportions of eyes pinhole blind due to cataract, which have been operated so far.
The numerator includes all (pseudo) aphakic eyes. The denominator includes the numerator, plus eyes pinhole blind due to cataract. Besides this, the indicator can also be calculated separately for PinVA <6/60 and <6/18.


Table: Barriers to cataract surgery in population aged ≥ 50 years with bilateral pinhole VA<3/60 due to cataract in West Delhi, Delhi

 Males (%)Females (%) Total (%)
Need not felt 50.00.015.3
Fear 25.044.438.5
Cost25.022.223.1
Treatment denied by provider 0.022.215.4
Unaware treatment is possible 0.011.17.7
Cannot access treatment 0.00.00.0
Local reason 0.00.10.0

Table: Cataract surgical coverage in population aged ≥ 50 years in West Delhi, Delhi.

 Males (%) Females (%) Total (%)
Cataract Surgical Coverage (persons) - percentage
Pin hole VA < 3/60 97.996.497.0
Pin hole VA < 6/60 95.094.594.7
Pin hole VA < 6/18 83.784.984.4
Cataract Surgical Coverage (eyes) - percentage
Pin hole VA < 3/60 90.487.688.9
Pin hole VA < 6/60 85.484.184.7
Pin hole VA < 6/18 69.071.070.1