1. Cataract Surgical Burden in Ghana
Presentation at OSG CPD Programme

2. Our Cataract Challenge
Estimated for 2017
159,456 Cataract Blind

3. Cataract Control Strategies
Cataract Output
How many surgeries?
How can we increase?
Cataract Outcomes
Are surgery results best quality at all times
Cataract Outlay
Cost?
Can services be made sustainable?

4. Cataract Output Cataract Backlog (Prevalence) Incidence
All untreated cases of cataract at present
Incidence
New cases developing
Estimated to be 20% of backlog
To reduce backlog number of cataract op performed each year must be a least equal to number of new cases of cataract (incidence)

5. Cataract output New cases (incidence) Cataract backlog Mortality
We can use the analogy of a leaky can to help us analyse the cataract output situation for a population of one million.
Within the can is the cataract backlog – these are all the untreated cases of cataract at present (known as the prevalence).
There are two exits from the can for the individuals with cataract. One is to receive treatment, the other option sadly is to die blind without ever seeing an eye health worker. As health workers it is our ambition that no one has to experience this fate.
We need to remember that the population is not static and that new cataract cases will develop over time. These are constantly entering into the backlog - shown here as new cases pouring into the leaky can. This is known as the incidence of cataract.
To reduce the cataract backlog, the number of cataract operations that need to be performed each year must be at least equal to the number of new cases, or incidence, of cataract.
Mortality
Treatment

6. 1 million population 1,000 new cases
Prevalence of blindness 1% =10,000 people blind
Cataract is main cause of blindness
Cataract backlog
= 5,000 people
or 10,000 eyes
Let’s put some numbers into our leaky can! A 1 million population with a prevalence of blindness of 1% means there are 10,000 people with a visual acuity of less than 3/60 in the better eye. If cataract is the main cause of blindness in half these people then the cataract backlog is 5,000 people or 10,000 eyes.
It has been calculated that cataract incidence is about 20% of the backlog so we can expect about another 1,000 people to have cataract by next year. If no treatment is carried out, and there is no mortality, by next year there will be 6,000 people in the backlog.

7. 1,000 = minimum number of surgeries next year to keep backlog in check
1,000 new cases
Cataract backlog
= 5,000 people
or 10,000 eyes
If we are to have any cataract control the minimum number of surgeries that must be done in the next year is 1,000 to keep the backlog in check.

8. Cataract Surgical Rate (CSR)
Number of cataract surgeries carried out per million pop per year CSR = Cataract operations per year/Populations in millions Minimum CSR needs to be equal to new cases (incidence) for it to begin to have any impact on the cataract backlog

9. Targets for cataract surgical rate
Africa target: 2,000
Asia target: 3,000
The global initiative, VISION 2020: the Right to Sight, set targets for cataract surgical rates to help address and reduce the backlog.
For Africa the rate is 2,000
For Asia the rate is 3,000
These targets are based on the availability of human resources to facilitate surgery.

11. Cataract Surgical Coverage (CSC)
How much of the need for cataract surgery has been met in a population CSC = Number who have had surgery/Number who have had surgery + Number still waiting Needs a RAAB survey for this

12. Cataract Surgical Burden in Ghana
Estimated population (2017) = 28,956,587
Prevalence of Blindness in Ghana = 0.74%
Proportion of cataract = 54.8%

13. Cataract Surgical Burden
Pop = 29 million
Number blind (VA = or < 3/60) = 0.74% of 29 million = 214,600
Number Blind from Cataract = 55% of 214,600 = 132,880 (Prevalence)
New cases = 20% of 132,880 = 26,576 (Incidence)
Total Estimate = 159,456