For treating advanced cataracts in the Developing World

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Cataract Surgery
in the
Developing World
Dr Brad Townend
BSc(Med), MBBS, MPH, MMED, FRANZCO
A Blinding Problem…
• Cataract is the leading cause of blindness in the world
– Defined as VA <6/120
• More than 20 million people in the world ‘blind’ due to cataract
• 1999: International Agency for the Prevention of Blindness (IAPB)
and the World Health Organization (WHO)
 “Vision 2020: The Right to Sight” initiative.
• Mission: sustainable provision of high-quality cataract surgical
services throughout the underdeveloped world.
• At the start: number of people blinded by cataract projected to
double by year 2020 if no improvements in global eye care delivery
• Significant progress has been made in quantity and quality of
cataract surgery provided in Developing World
Q1: What is the leading cause
of blindness in the world?
A
B
C
D
Cataract
Glaucoma
AMD
Infection / Uveitis
Intracapsular Surgery
•
•
•
•
•
No IOL technology
Large wound
Zonule dissolving solution, cryo probe
Time consuming surgery
Ocular complications significant
– RD, CMO, expulsive haemorrhage, infection
• Significant morbidity (weeks in hospital)
• Remain aphakic with spectacle correction
Harold Ridley
• WWII Royal Air Force casualties
• Splinters of plastic (acrylic) from
shattered aircraft cockpit canopies
became lodged in the eyes of wounded
pilots
• Inert (did not trigger rejection or
inflammation)
•  artificial lenses for cataract surgery
• Much opposition from the medical
community initially
• Finally approved by FDA as ‘safe and
effective’ for human use in 1981
Q2: Harold Ridley implanted the first
IOL in 1950 made of what material?
A
B
C
D
Glass
Silicon
Quartz
Acrylic / Perspex
Extracapsular Surgery
– Preserve capsule for IOL insertion
– 10 mm limbal incision (astigmatism)
– 8-10 sutures
• Astigmatism, time, suture removal, complications
– Slow visual rehabilitation
Phaco-Emulsification
•
•
•
•
Better refractive and visual outcomes
Quicker surgical time (sutureless)
Fewer complications
Fast rehabilitation
BUT
•
•
•
•
High cost of equipment
Maintenance
Consumables
Most blind people live in developing world
Q3: Which of the following is a
disadvantage of phaco-emulsification
over traditional extracapsular surgery?
A
B
C
D
Faster rehabilitation time
Astigmatism
Cost
No need for sutures
SICS
Small Incision Cataract Surgery
• Good quality outcomes
• Cheap ($20 AUD per case)
–
–
–
–
•
•
•
•
Cheap tools
Cheap lenses
No phaco machine
Few consumables (except blades)
Efficient surgical times (5 minutes) and turnaround times (3 minutes)
Sutureless
Much easier and quicker to learn than phaco
More forgiving than phaco when complications
– Particularly for difficult dense cataracts
• Can’t do SICS on soft Western cataracts!
• Much fewer post-op visits than ECCE
• Better VA outcomes than ECCE, and almost as good phaco
Q4: Which of the following is a
limitation of SICS surgery?
A
B
C
D
Cheap
Difficult to perform on soft
Western cataracts
Efficient surgical times
Astigmatism
OUTCOMES: SICS vs Phaco in
Developing World
•
•
•
•
•
•
•
3 RCT’s
Phaco: more corneal oedema on day 1 post-op with worse VA on day 1
No significant difference in endothelial cell loss between techniques at 6 weeks
Phaco had higher rates of UCVA >6/9 and BCVA >6/6 compared to SICS
At 6 months: rate of BCVA and UCVA >6/18 similar between phaco and SICS
Phaco took 15.5 mins on average, SICS took 9 mins
PCO rate significantly higher in SICS group at 6 months (but VA not worse!)
– Needs longer follow-up
• Complication rates (including endophthalmitis) similar
• BUT:
– SICS more efficient and economical
– SICS faster visual rehabilitation
(For treating advanced cataracts in the Developing World)
Q5: Which of the following is true for
treating advanced cataracts in the
Developing World?
A
B
C
D
SICS is more efficient, economical and has
outcomes that are just as good as phaco
SICS causes more corneal oedema than phaco
Phaco has quicker post-op rehabilitation
SICS has more complications
References
• Gogate P, Deshpande M, Nirmalan PK. Why do phacoemulsification?
Manual small-incision cataract surgery is almost as effective, but less
expensive. Ophthalmology. 2007;114:965–968.
• Gogate PM, Kulkarni SR, Krishnaiah S, et al. Safety and efficacy of
phacoemulsification compared with manual small-incision cataract
surgery by randomized controlled clinical trial. Ophthalmology.
2005;112:869–874.
• Ruit S, Tabin G, Chang D, et al. A prospective randomized clinical trial of
phacoemulsification vs manual sutureless small-incision extracapsular
cataract surgery in Nepal. Am J Ophthalmol. 2007;143:32–38.
• Ruit S, Tabin GC, Nissman SA, Paudyal G, Gurung R. Low-cost high-volume
extracapsular cataract extraction with posterior chamber intraocular lens
implantation in Nepal. Ophthalmology. 1999;106:1887–1892.
• Tabin G, Chen M, Espandar L. Cataract surgery for the developing world.
Curr Opin Ophthalmol. 2008;19:55–59.
FIJI
NEPAL
ALICE SPRINGS
EYE CHART:
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