Clinical and Experimental Ophthalmology
Vgm*5a6t 2006;
V]zZb-m= 34
* +
T(i : 880–885
:82T! doi:10.1111/j.1442-9071.2006.01342.x
CE"/&I © 2006 Royal Australian and New Zealand College of Ophthalmologists
q9
Df`6+ l7QxngWw Correspondence:
')jItje| Dr Garry Brian, 5 Hazelmere Parade, Sherwood, Qld 4075, Australia. Email:
grbrian@tpg.com.au -Y_,
.'ex Received 11 April 2006; accepted 19 June 2006.
Us`=^\ Original Article
VMah3T! Cataract and its surgery in Papua New Guinea
lY,^ Jambi N Garap
u`|%qRt MMed(Ophthal)
^Iw$( ,
7.
F'1oEf 1,2
ZthT('"a Sethu Sheeladevi
~b_DFj MHM
12 p`ZD= ,
t}+/GSwT 3
:^7w Garry Brian
JxIJxhA> FRANZCO
"L3mW=!* ,
g Wtc3 2,4
0B.Gt&Oal BR Shamanna
tSHW"R MD
`n&:\Ib ,
R4p Pt 3
Tpl]\L1v- Praveen K Nirmalan
D:T]$<=9 MPH
&ijz'Sg3 3
_a$qsY and Carmel Williams
Y4k2=w:D MA
`2Pa{g-. 4
fZiAl7b! 1
01r%K@ xX\ The Fred Hollows Foundation – Papua New Guinea Eye Care Program,
TIGtX]` 2
vT?^# Department of Ophthalmology, School of Medicine and Health
b~aM=71 Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea;
rUI?{CV 3
ovKM;cRs/ International Center for Advancement of Rural Eye Care,
;wwc;wQ' L.V. Prasad Eye Institute, Hyderabad, India; and
4)gG_k 4
zj7ta[<tr The Fred Hollows Foundation (New Zealand), Auckland, New Zealand
p@jw)xI Key words:
M@ U>@x; blindness
3RaduN] ,
u`'"=Y_E cataract
$cSUB ,
`;85Mo:qJ Papua New Guinea
Mq\=pxC@ ,
D7hTn@I surgery
flCT]ZR ,
fl-J:`zyyZ vision impairment
;FqmZjm .
qHk{5O3 I
e"hfeNphz NTRODUCTION
gWr7^u&q@| Just north of Australia, tropical Papua New Guinea (PNG)
S>oEk3zlw has more than five million people spread across several major
pA!-spgX and hundreds of other smaller islands. Almost 50% of the
mG1~rI land area is mountainous, and 85% of inhabitants are rural
p]kEH\
sh dwellers. Forty per cent of the population is age 14 years or
lsax.uG5x younger, and 9% is 50 years or older.
X$!fR >Zc 1
HTL6;87w+] Papua New Guinea was administered by Australia until
H_?rbz} o 1975, when independence was granted. Since that time, governance,
!FgZI4?/Y= particularly budgetary, economic performance, law
s, Gl{ and justice, and development and management of basic
|.@!CqJ health and other services have declined. Today, 37% of the
uZld9u population is said to live below the poverty line, personal
Tf3CyH!k and property security are problematic, and health is poor.
"WKOlfPa There are significant and growing economic, health and education
"AagTFs(i disparities between urban and rural inhabitants.
"}3sL#|z Papua New Guinea has one referral hospital, in Port
&@6xu{o Moresby. This has an eye clinic with one part-time and two
y_9\07va< full-time consultant ophthalmologists, and several ophthalmology
[KA^
+n training registrars. There are also two private ophthalmologists
t~L4wr{B in the city. Elsewhere, four provincial hospitals
Q^ W,)% have eye clinics, each with one consultant ophthalmologist.
7{<v$g$ One of these, supported by Christian Blind Mission and
H8YwMhE7 based at Goroka, provides an extensive outreach service.
+mrLMbBiD Visiting Australian and New Zealand ophthalmology teams
N}5 and an outreach team from Port Moresby General Hospital
ykC3Z<pI. provide some 6 weeks of provincial service per year.
~R;/u")@e Cataract and its surgery account for a significant proportion
_WNbuk0 of ophthalmic resource allocation and services delivered
@K <Onh` in PNG. Although the National Department of Health keeps
\lg
^rfj some service-related statistics, and cataract has been considered
G
y[5'J` in three PNG publications of limited value (two district
K^!#;,0 service reports
V<
F&\ 2,3
;?{^LiD+F and a community assessment
%fg6',2 4
+=/j
+S` ), there has
e\X[\ve been no systematic assessment of cataract or its surgery.
Zd-qBOB2L A
1{M?_~g4 BSTRACT
L--
t(G Purpose:
,LwinjHA* To determine the prevalence of visually significant
~+{*KPiD cataract, unoperated blinding cataract, and cataract surgery
h
8$.m
Qr for those aged 50 years and over in Papua New Guinea.
"81'{\(I_ Also, to determine the characteristics, rate, coverage and
|"K%Tvxe outcome of cataract surgery, and barriers to its uptake.
'|gsmO Methods:
_1?u AQ3, Using the World Health Organization Rapid
B=*0 Assessment of Cataract Surgical Services protocol, a population-
<%.%
q based cross-sectional survey was conducted in
(LsVd2AbR 2005. By two-stage cluster random sampling, 39 clusters of
/\Nc6Z/ L 30 people were selected. Each eye with a presenting visual
X[Iy6q
t acuity worse than 6/18 and/or a history of cataract surgery
J t.<Z& was examined.
;q'-<O Results:
8\;, d Of the 1191 people enumerated, 98.6% were
!r.-7hR $ examined. The 50 years and older age-gender-adjusted
s2L]H prevalence of cataract-induced vision impairment (presenting
=xkaF)AW&v acuity less than 6/18 in the better eye) was 7.4% (95%
ue3 ].: confidence interval [CI]: 6.4, 10.2, design effect [deff]
A)~oD_ooQ =
.}F
39TS2 1.3).
kj2qX9Ms That for cataract-caused functional blindness (presenting
*[cCY!+Qy acuity less than 6/60 in the better eye) was 6.4% (95% CI:
]4B;M Ym* 5.1, 7.3, deff
ag8)^p'9 =
n]vCvmt 1.1). The latter was not associated with
#3ZAMV gender (
enxb
pq# P
tWl')^ =
_LgP 0.6). For the sample, Cataract Surgical Coverage
q/w5Dx|: at 6/60 was 34.5% for Eyes and 45.3% for Persons. The
z z]~IxQ Cataract Surgical Rate for Papua New Guinea was less than
[,st: Y 500 per million population per year. The age-genderadjusted
yLqhj7 prevalence of those having had cataract surgery
yU(}1ZID was 8.3% (95% CI: 6.6, 9.8, deff
"<Di =
$C=XSuPNK 1.3). Vision outcomes of
((AK7hb surgery did not meet World Health Organization guidelines.
1LFad>` Lack of awareness was the most common reason for not
3,Z;J5VL4! seeking and undergoing surgery.
$#%R_G] Conclusion:
x]Nx,tt Increasing the quantity and quality of cataract
VxOWv8}| surgery need to be priorities for Papua New Guinea eye
1Cc91 care services.
Q7`)&^
Hx Cataract and its surgery in Papua New Guinea 881
jB9~'>JY © 2006 Royal Australian and New Zealand College of Ophthalmologists
Xa-TNnws? This paper reports the cataract-related aspects of a population-
*Q2 oc:6 based cross-sectional rapid assessment survey of
Mx0~^l those 50 years and older in PNG.
vnf2Z,f% M
GGLSmfb) ETHODS
e7n0=U0 The National Ethical Clearance Committee of The Medical
?t}s3P!Q3w Research Advisory Committee granted ethics approval to
IrRe
6nf@K survey aspects of eye health and care in Papua New Guinea
!:xE
X~ (MRAC No. 05/13). This study was performed between
k!z.6di December 2004 and March 2005, and used the validated
s 7%iuP World Health Organization (WHO) Rapid Assessment of
E>#@
H Cataract Surgical Services
J7dHD(R8 5,6
L|D9+u L protocol. Characterization of
$AZ=;iP- cataract and its surgery in the 50 years and over age group
@b2?BSdUp was part of that study.
rT-.'aQ2t As reported elsewhere,
L>Ze*dt 7
toj5b;+4F the sample size required, using a
sAjUX.c prevalence of bilateral cataract functional blindness (presenting
GaJE(N visual acuity worse than 6/60 in both eyes) of 5% in the
f `b6E J target population, precision of
Dbx zqd ±
,\\=f#c= 20%, with 95% confidence
PxW
H
)4 intervals (CI), and a design effect (deff) of 1.3 (for a cluster
+|<bb8% size of 30 persons), was estimated as 1169 persons. The
2t0VbAO1{ sample frame used for the survey, based on logistics and
aWvC-vZk security considerations, included Koki wanigela settlement
.;U?%t_7 in the Port Moresby area (an urban population), and Rigo
9J_vvq`%` coastal district (a rural population, effectively isolated from
F}F{/
Port Moresby despite being only 2–4 h away by road). From
1o_Zw. this sample frame, 39 clusters (with probability proportionate
<Nloh+n= to population size) were chosen, using a systematic random
8
t7r^[T sampling strategy.
1Qjc*+JzO. Within each cluster, the supervisor chose households
TgLr4Ex using a random process. Residency was defined as living in
MCXt,`}[ that cluster household for 6 months or more over the past
RZ9_*Lq7+ year, and sharing meals from a common kitchen with other
)\W}&9 > members of the household. Eligible resident subjects aged
U(~Nmo' 50 years and older were then enumerated by trained volunteers
m<;MOS from the Port Moresby St John Ambulance Services.
J!Rqm!)q This continued until 30 subjects were enrolled. If the
Q2m 5&yy@s required number of subjects was not obtained from a particular
<P*7u\9& cluster, the fieldworkers completed enrolment in the
C.}ho.}
r nearest adjacent cluster. Verbal informed consent was
w8KxEV= obtained prior to all data collection and examinations.
D-m%eP. A standardized survey record was completed for each
?H{?jJj$H participant. The volunteers solicited demographic and general
f7%g=0.F information, and any history of cataract surgery. They
h,/3} also measured visual acuity. During a methodology pilot in
F"tM?V.| the Morata settlement area of Port Moresby, the kappa statistic
xi.QHKBZaH for agreement between the four volunteers designated
7 lq$PsC to perform visual acuity estimations was over 0.85.
e&mTaCLG The widely accepted and used ‘presenting distance visual
:X 1Y acuity’ (with correction if the subject was using any), a measure
;>]dwsA*P of ocular condition and access to and uptake of eye care
[2
Rz8e^ services, was determined for each eye separately. This was
dVJ9cJ9^ done in daylight, using Snellen illiterate E optotypes, with
1
"1ElH four correct consecutive or six of eight showings of the
tg ~7^(s smallest discernible optotype giving the level. For any eye
3 "|A5>Vo with presenting visual acuity worse than 6/18, pinhole acuity
X(]J\?n' was also measured.
?xE'i[F @ An ophthalmologist examined all eyes with a history of
/DSy/p0% cataract surgery and/or reduced presenting vision. Assessment
L$ju~0jl)% of the anterior segment was made using a torch and
6x@]b>W loupe magnification. In a dimly lit room, through an undilated
J =#9eW pupil, the status of the visually important central lens
;|CG9|p was determined with a direct ophthalmoscope. An intact red
r+MqjdXG reflex was considered indicative of a ‘normal’ clear central
d^|r#"o[ lens. The presence of obvious red reflex dark shading, but
1a#R7
chl transparent vitreous, was recorded as lens opacity. Where
6 c-9[-Px present, aphakia and pseudophakia with and without posterior
9:Z|Z?>? capsule opacification were noted. The lens was determined
MIc(B_q to be not visible if there were dense corneal opacities
+AOpB L' or other ocular pathologies, such as phthisis bulbi, precluding
9kas]zQ%=P any view of the lens. The posterior segment was examined
H4e2#]*i7 with a direct ophthalmoscope, also through an
wq#'o9s, undilated pupil.
/<IXCM. A cause of vision loss was determined for each eye with
i#Fe`Z ~J a presenting visual acuity worse than 6/18. In the absence of
v/G^yZa any other findings, uncorrected refractive error was considered
Ozc9y y!% to be that cause if the acuity then improved to better
K`cy97 than 6/18 with pinhole. Other causes, including corneal
|Lz7}g=6 opacity, cataract and diabetic retinopathy, required clinical
Eqt>_n8 findings of sufficient magnitude to explain the level of vision
IpsV4nmnz- loss. Although any eye may have more than one condition
\
id(P3M contributing to vision reduction, for the purposes of this
+hMF\@ study, a single cause of vision loss was determined for each
9CHn6 v ~) eye. The attributed cause was the condition most easily
g7]g0*gxXW treated if each of the contributing conditions was individually
ch0x*[N@ treatable to a vision of 6/18 or better. Thus, for example,
T;B/Wm!x when uncorrected refractive error and lens opacity coexisted,
RS
Vt refractive error, with its easier and less expensive treatment,
)Z@hk]@?_[ was nominated as the cause. Where treatment of a condition
;UWp0d%
present would not result in 6/18 or better acuity, it was
@S Quc determined to be the cause rather than any coincident or
}719_DF associated conditions amenable to treatment. Thus, for
U{-[lpd example, coincident retinal detachment and cataract would
qk\LfRbj be categorized as ‘posterior segment pathology’.
_1HEGX\ Participants who were functionally blind (less than 6/60
.h;X5q1 in the better eye) because of unoperated cataract were interrogated
(I(k$g[> about the reasons for not having surgery. The
R~XNF/QMl responses were closed ended and respondents had the option
b]5S9^=LI of volunteering more than one barrier, all of which were
%Z#[{yuFs recorded in a piloted proforma. The first four reasons offered
w'!J were considered for analysis of the barriers to cataract
;WsV.n surgery.
Zq"wq[GCN Those eyes previously operated for cataract were examined
*Ja,3Qq to characterize that surgery and the vision outcome. A
kZvh<NFh_ detailed history of the surgery was taken. This included the
PhC{Gg age at surgery, place of surgery, cost and the use of spectacles
Qx !!
Ttd{ afterward, including reasons for not wearing them if that was
dZjh@yGP. the case.
KXga{]G: The Rapid Assessment of Cataract Surgical Services data
N`i`[ f entry and analysis software package was used. The prevalences
u:O6MO9^ of visually significant cataract, unoperated blinding
U-:_4[ cataract and cataract surgery were determined. Where prevalence
lIL{*q( estimates were age and gender adjusted for the population
~6:y@4&F of PNG, the estimated population structure for the
^Dhu8C( 882 Garap
h\$juIQa et al.
+S>}<OE © 2006 Royal Australian and New Zealand College of Ophthalmologists
9 k>=y n year 2000
'P?DZE 1
HxH=~B1"P was used, and 95% CI were derived around these
h ^6Yjy point estimates. Additional analysis for potential associations
`` mi9E of cataract, its surgery and surgical outcomes employed the
)Y+?)=~ STATA (version 8.0; StataCorp LP, TX, USA). Fisher’s exact
9ApGn!` test and the chi-square test for bivariate analysis and a multiple
= g)G! logistic regression model for multivariate analysis were
aF\?X&| used. Odds ratios (OR) and 95% CI were estimated. A
x2gP, p- P
]tVXao -
m}3POl/*j value of
Bswd20(w <
\dag~b< 0.05 was taken as significant for this analysis.
S*1Km& The Cataract Surgical Coverage (Eyes) (CSC(Eyes)) was
(^Kcyag4 calculated. This is a surgical service impact indicator. It measures
:{v:sK the proportion of cataract that has been operated on
[oQ&}3\XJ in a defined population at a particular point in time, being
-f-2!1&<3h the eyes having had cataract surgery as a percentage of the
&`'gO
9 combined total of all of those eyes operated with those
mJ|7Jc currently blind (less than 6/60) from cataract (CSC(Eyes) at
=Gq
'sy:h 6/60
JDzkv%E^ =
q(yw,]h]{ 100
cKX6pG a
E0 Vl}b /(
J
dDP a
q#RV
i8(' +
TvWhy`RQ b
hsQrHs'k ), where
a]465FY a
D>O{>;y[
=
M,Px.@tw. pseudophakic
96Tc:#9i +
I$neE"wW aphakic eyes,
S`"M;%T and
i%W,Y8\uf* b
!o 7uZC\ =
5U[;T]{)e eyes with worse than 6/60 vision caused by cataract).
[PrR30: 8
9b !+kJD The Cataract Surgical Coverage (Persons) (CSC(Persons))
(iK0T. was determined. This considers people with operated
X./4at` cataract (either or both eyes) as a proportion of those having
0rT-8iJp4P operable cataract. (CSC(Persons) at 6/60
+MQf2|-- =
I ,AI$A 100(
C/[2?[ x
~2~KcgPsq +
oS$&jd y
]P ->xJ )/
(G"b)"Qum (
EPr{1Z x
}_M.-Xm +
D|Z,eench y
$+ZO{
( +
W?'!}g(~ z
^<<( }3 ), in which
-2tX 15, x
^#S =
7s5?^^ persons with unilateral pseudophakia
6yTL7@V|B or unilateral aphakia and worse than 6/60 vision
2X)E3V/*
caused by cataract in the other eye,
?YgK]IxD y
\Ul*Nsw =
QhZ!A?':U persons with bilateral
Q_6./.GQ
previously operated cataract, and
{*t'h?b z
L|6c lGp =
g=b[V
persons with bilateral
\(Zdd
\, cataract causing vision worse than 6/60 in each).
d)r=W@tF] 8
:'I mz The Cataract Surgical Rate, being the number of cataract
P!B\:B%4~] operations per year per million of population, was also
LD_aJ^(d estimated.
!&E>8h R
pR 1 v^m| ESULTS
:XBeGNI*# Of the 1191 people enumerated, 5 subjects were not available
s.C-II?e during the survey and 12 refused participation. Data
_4zlEo-.gU from these 17 were not considered in the analysis. Of the
wOHK
dQ' remaining 1174 (98.6%), 606 (51.6%) were female, and 914
kt X(\Hf! (77.9%) were domiciled in rural Rigo.
s;8J= \9W Cataract caused 35.2% of vision impairment (presenting
&ks>.l\ vision less than 6/18) and 62.8% of functional blindness
dW8'$!@!! (presenting vision less than 6/60) in the 2348 eyes sampled
b*dRNu (Table 1). It was second to refractive error (45.7%)
;?z b ( 2 7
O~fRcf:Q in the
(M.Sl former, and the leading cause of the latter.
`U(A 5 For the 1174 subjects, cataract was the most prevalent
SRM[IU
cause of vision impairment (46.7%) and functional blindness
)]>=Uo (75.0%) (Table 1). On bivariate analysis, increasing age
MfeW|
(
:Nc~rOC_ P
_a15R/S <
1vl~[ 0.001), illiteracy (
]jY->NsA] P
w`>xK
sKW> <
x-y=Jor 0.001) and unemployment
T`a [~: (
2$[u&__E P
{_^sR}%]F <
_6=6 b!hD 0.001) were associated with cataract-induced functional
d+2I+O03 blindness. Gender was not significantly associated (
iOki ZN+d> P
#Y`U8n2F =
.O1g'% 0.6).
Q*mPU=< In a multivariate model that included all variables found
O%0G37h significant in bivariate analysis, increasing age (reference category
qMI%=@= 50–59 years; OR: 2.6, 95% CI: 1.6, 5.9 for persons
qr<5z. % aged 60–69, OR: 9.8, 95% CI: 4.6, 20.6 for persons aged
O;qS3 70–79, and OR: 18.6, 95% CI: 8.3, 41.9 for persons aged
'7xmj:.== 80 years and older) and illiteracy (OR 2.2, 95% CI 1.3, 3.8)
? 76jz>;b were associated with functional cataract blindness.
[Y'Xop6G The survey sample included 97 people (8.3%) who had
WNd(X} previously undergone cataract surgery, for a total of 136 eyes
Ae`K
9 (5.8%). On bivariate analysis, increasing age (
Qs;bVlp!H P
#[I`VA\x =
mI"|^!L 0.02), male
?LvZEiJ gender (
Dyt}"r\ P
,Y9lp)w =
pmQ9iA@= 0.02), literacy (
QabF(}61
P
q\mVZyj <
8b|& 0.001) and employed status
sbkWJy (
/o8h1L= P
";s?#c =
HRPT
P+ 0.03) were associated with cataract surgery. Illiteracy
WI}P(!h\J was significantly associated with reduced uptake of cataract
\7gLk: surgery (adjusted OR 0.43, 95% CI: 0.20, 0.91) in a multivariate
}@a_x,O/x} model that adjusted for age, gender and employment
f4`=yj* status.
f5d"H6%L The CSC(Eyes) at 6/60 for the survey sample was
A9$q;8= < 34.5%, and the CSC(Persons) at the same vision level was
ETjlq]@j 45.3%.
8BLtTpu Most cataract surgery occurred in a government hospital
N55;oj_K (
Q@/wn P
&W`yHQ"JY <
~G5)ya- 0.001), more than 5 years ago (
j"J2&Y2 P
LuR.; TiW <
",`fGu ) 0.001). Also, most
jIAl7aoY of the intracapsular extractions were performed more than
s{`r$:! 5 years ago (
{$O.@#' P
/`}C~ <
Lgvmk 0.001). Patients are now more likely to
& UL(r receive intraocular lens surgery (
eP[azC"G[ P
r$R(4q: <
f=g/_R2$xN 0.001). Although most
2/qfK+a surgery was provided free (
b!<?,S P
FU5vo =
!-LPFy> 0.02), males, who were more
C4TJS,!1rH likely to have surgery (
'zi5ihiT P
"2N3L8?k =
Gvl-q1PVC 0.02), were also more likely to
YeYF
Pi# pay for it (
byyz\>yAVq P
Pm7,Nq)<>n =
p,$1%/m 0.03) (Table 2).
:$dGcX} As measured by presenting acuity, the vision outcomes of
Y'%sA~g both intracapsular surgery and intraocular lens surgery were
}!lLA4XRr poor (Table 3). However, 62.6% of those people with at least
n M,m#"AI Table 1.
<