Clinical and Experimental Ophthalmology
GQ2GcX(E( 2006;
Xp<q`w0I, 34
ah>c)1DA*H : 880–885
L/k35 x8 doi:10.1111/j.1442-9071.2006.01342.x
19 5_1?'< © 2006 Royal Australian and New Zealand College of Ophthalmologists
]RVu[k8 1p&.\ ^ Correspondence:
{K^5q{u Dr Garry Brian, 5 Hazelmere Parade, Sherwood, Qld 4075, Australia. Email:
grbrian@tpg.com.au <=(K'eqC^ Received 11 April 2006; accepted 19 June 2006.
L+t
/
E` Original Article
JrP`u4f_ Cataract and its surgery in Papua New Guinea
.K
C*
(}- Jambi N Garap
&RR;'wLoQT MMed(Ophthal)
\!ZA#7 ,
c`E>7Hjr- 1,2
gt
Kih Sethu Sheeladevi
y?sz&*: MHM
2&hv6Y1 ,
GT6; I7 3
>+O0W)g{o Garry Brian
-Jv,#Z3 FRANZCO
|d0X1( ,
=?]`Xo,v~ 2,4
RDps{),E;d BR Shamanna
<IrhR,@M,L MD
G^'We6< ,
kNuvJ/St 3
a1,)1y~ Praveen K Nirmalan
rCJ$Pl9R MPH
tP_.-// 3
@!;A^<{ka and Carmel Williams
rtPo)#t MA
3MQHoxX 4
&XNt/bK-? 1
|=5zI6pT The Fred Hollows Foundation – Papua New Guinea Eye Care Program,
lz^Vi!|p 2
XT/t\\Z`U Department of Ophthalmology, School of Medicine and Health
S @[]znH Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea;
1
-Z&/3T] 3
7\@c1e*e
International Center for Advancement of Rural Eye Care,
SX,$$43 L.V. Prasad Eye Institute, Hyderabad, India; and
HOi~eX1d 4
<v1H1'
gv The Fred Hollows Foundation (New Zealand), Auckland, New Zealand
&n*ga$Q Key words:
fAh|43Y*a blindness
OX,em Ti ,
u.E>d9 cataract
Q``1^E' ,
Av.`'.b Papua New Guinea
27}:f?2hbJ ,
2fdN@iruB surgery
`*[Kmb\ ,
,b^Y8_ltoT vision impairment
\HxF?i " .
a|TUH+| I
,7$&gx>2& NTRODUCTION
pZ $>Hh# Just north of Australia, tropical Papua New Guinea (PNG)
-Tvnd, has more than five million people spread across several major
ke@OG! M / and hundreds of other smaller islands. Almost 50% of the
_W@sFv%sj land area is mountainous, and 85% of inhabitants are rural
?taC
!{ dwellers. Forty per cent of the population is age 14 years or
q'fOlq younger, and 9% is 50 years or older.
zvN7aG 1
CUB;0J( Papua New Guinea was administered by Australia until
Gy+c/gK 1975, when independence was granted. Since that time, governance,
=H: N!!: particularly budgetary, economic performance, law
=2*2$ and justice, and development and management of basic
l _2Xao$ health and other services have declined. Today, 37% of the
7E*0;sA# population is said to live below the poverty line, personal
r}Vr_ and property security are problematic, and health is poor.
lB_4jc There are significant and growing economic, health and education
'"q+[zwv disparities between urban and rural inhabitants.
&'neOf/~ Papua New Guinea has one referral hospital, in Port
%/)z!}{ Moresby. This has an eye clinic with one part-time and two
DZ`,QWuA full-time consultant ophthalmologists, and several ophthalmology
}.u[';q]S training registrars. There are also two private ophthalmologists
3 p -SpUvp in the city. Elsewhere, four provincial hospitals
)-XD=
] have eye clinics, each with one consultant ophthalmologist.
e Vj
8u One of these, supported by Christian Blind Mission and
zWN]#W` based at Goroka, provides an extensive outreach service.
Hl}m*9<9us Visiting Australian and New Zealand ophthalmology teams
7u1o>a%9 and an outreach team from Port Moresby General Hospital
A\"4[PXpQ provide some 6 weeks of provincial service per year.
$v8T%'p+ Cataract and its surgery account for a significant proportion
Q=<
&ew of ophthalmic resource allocation and services delivered
-R$ Q`
Xw in PNG. Although the National Department of Health keeps
lh\`9F: some service-related statistics, and cataract has been considered
dF|n)+C~R in three PNG publications of limited value (two district
9e;{o,r@ service reports
5OTZa>H 2,3
D1]?f` and a community assessment
)):D&wlq 4
SbtZhg=S_ ), there has
M6[O>z been no systematic assessment of cataract or its surgery.
? _[q{i{ A
Kk \,q? BSTRACT
!}d_$U$ Purpose:
;%AY#b4m To determine the prevalence of visually significant
| m#" cataract, unoperated blinding cataract, and cataract surgery
e{Mkwi+j for those aged 50 years and over in Papua New Guinea.
lo7>$`Q Also, to determine the characteristics, rate, coverage and
L$]Y$yv outcome of cataract surgery, and barriers to its uptake.
>(gbUW Methods:
|UQGZ Using the World Health Organization Rapid
On;7 Assessment of Cataract Surgical Services protocol, a population-
>b*}Td~J based cross-sectional survey was conducted in
BE!WCDg, 2005. By two-stage cluster random sampling, 39 clusters of
X-yS9E 30 people were selected. Each eye with a presenting visual
U@".XIDQ acuity worse than 6/18 and/or a history of cataract surgery
e=i9l was examined.
1mv8[^pF Results:
D'Kiy Of the 1191 people enumerated, 98.6% were
K pKZiUQm examined. The 50 years and older age-gender-adjusted
xqj@T^y prevalence of cataract-induced vision impairment (presenting
_ o6Zj1p acuity less than 6/18 in the better eye) was 7.4% (95%
na|23jz4 confidence interval [CI]: 6.4, 10.2, design effect [deff]
d`xDv$QZ =
RPTIDA)) 1.3).
8J
0#lu That for cataract-caused functional blindness (presenting
\lpvRZ\L&g acuity less than 6/60 in the better eye) was 6.4% (95% CI:
#@cEJV;5" 5.1, 7.3, deff
fp$U%uj =
YZc{\~d 1.1). The latter was not associated with
<OGXKv@ gender (
}h
o6 P
vn.j>;E' =
CuYSvW 0.6). For the sample, Cataract Surgical Coverage
d?jzh1 at 6/60 was 34.5% for Eyes and 45.3% for Persons. The
q[~+Zm Cataract Surgical Rate for Papua New Guinea was less than
IoxdWQ4]A 500 per million population per year. The age-genderadjusted
(+.R8 prevalence of those having had cataract surgery
pLpWc~# was 8.3% (95% CI: 6.6, 9.8, deff
B"Ttr+ =
e/y\P&"eI 1.3). Vision outcomes of
m 3"|$0C~ surgery did not meet World Health Organization guidelines.
u|M_O5^ Lack of awareness was the most common reason for not
8Rd*`]@[pk seeking and undergoing surgery.
Q1u/QA:z7 Conclusion:
3W"l}.&ZJ" Increasing the quantity and quality of cataract
6e:#x:O surgery need to be priorities for Papua New Guinea eye
7G
&I]> care services.
vC%8-;8{H Cataract and its surgery in Papua New Guinea 881
'mE!,KeS; © 2006 Royal Australian and New Zealand College of Ophthalmologists
.a]9 rQQ&_ This paper reports the cataract-related aspects of a population-
I@o42% w2 based cross-sectional rapid assessment survey of
gSXidh}^ those 50 years and older in PNG.
'(yjq< M
DjveMs$d ETHODS
S3.76& The National Ethical Clearance Committee of The Medical
}(Dt,F` Research Advisory Committee granted ethics approval to
hScC<=W survey aspects of eye health and care in Papua New Guinea
S[I-Z_S (MRAC No. 05/13). This study was performed between
gP:H_nVh December 2004 and March 2005, and used the validated
`w#p8vR World Health Organization (WHO) Rapid Assessment of
Tt\G
y Cataract Surgical Services
jP"l5 5,6
wJu,N(U protocol. Characterization of
~mK|~x01@ cataract and its surgery in the 50 years and over age group
bz\-%$^k was part of that study.
U6yZKK As reported elsewhere,
?'+kZ| 7
CH+mzy the sample size required, using a
O[<0\ prevalence of bilateral cataract functional blindness (presenting
ERz{, >G? visual acuity worse than 6/60 in both eyes) of 5% in the
Uy5G,! target population, precision of
0mi$_Ld+ ±
6Us*zKgW 20%, with 95% confidence
}?^5L7n intervals (CI), and a design effect (deff) of 1.3 (for a cluster
{'$+?V"& size of 30 persons), was estimated as 1169 persons. The
w sample frame used for the survey, based on logistics and
@z1pE@7jK security considerations, included Koki wanigela settlement
Dwuao`~Xm in the Port Moresby area (an urban population), and Rigo
.LA?2N coastal district (a rural population, effectively isolated from
EaUO>S Port Moresby despite being only 2–4 h away by road). From
\<0xg[ this sample frame, 39 clusters (with probability proportionate
bT
bF to population size) were chosen, using a systematic random
83g$k
9lG. sampling strategy.
M"
R=;n Within each cluster, the supervisor chose households
gOLN7K-) using a random process. Residency was defined as living in
Ze"m;T that cluster household for 6 months or more over the past
jHQnD]Hr year, and sharing meals from a common kitchen with other
p4^&G/' members of the household. Eligible resident subjects aged
Y4Y~ep 50 years and older were then enumerated by trained volunteers
S?<hs,
from the Port Moresby St John Ambulance Services.
,jq:%Y[KZ This continued until 30 subjects were enrolled. If the
5N(OW:M required number of subjects was not obtained from a particular
fprP$MbI cluster, the fieldworkers completed enrolment in the
/_qW?LKG/ nearest adjacent cluster. Verbal informed consent was
&(X 67 obtained prior to all data collection and examinations.
4~i?xo=;v A standardized survey record was completed for each
[ahK+J participant. The volunteers solicited demographic and general
oe<DP7e information, and any history of cataract surgery. They
kJK*wq]U6 also measured visual acuity. During a methodology pilot in
_o7t| pl~ the Morata settlement area of Port Moresby, the kappa statistic
,{X}C for agreement between the four volunteers designated
bCqTubbx!t to perform visual acuity estimations was over 0.85.
$8WWN} OC The widely accepted and used ‘presenting distance visual
&a.A8v) acuity’ (with correction if the subject was using any), a measure
JA~q}C7A7o of ocular condition and access to and uptake of eye care
X^Fc^U8 services, was determined for each eye separately. This was
3?e~J"WXC5 done in daylight, using Snellen illiterate E optotypes, with
otbr8&?- four correct consecutive or six of eight showings of the
@Yn+ir0>O smallest discernible optotype giving the level. For any eye
pp@O6 with presenting visual acuity worse than 6/18, pinhole acuity
yw1-4*$c was also measured.
3,?LpdTS An ophthalmologist examined all eyes with a history of
2Q 5-.2] cataract surgery and/or reduced presenting vision. Assessment
gI!d*]{BP of the anterior segment was made using a torch and
{krBAz& loupe magnification. In a dimly lit room, through an undilated
9oYE pupil, the status of the visually important central lens
?j&ZzK'#^ was determined with a direct ophthalmoscope. An intact red
WK0:3q(P reflex was considered indicative of a ‘normal’ clear central
Z/czAr@4 lens. The presence of obvious red reflex dark shading, but
vi28u xc transparent vitreous, was recorded as lens opacity. Where
Fw:_O2 present, aphakia and pseudophakia with and without posterior
,0c]/Sd*p capsule opacification were noted. The lens was determined
jZD)c_'U to be not visible if there were dense corneal opacities
Lt
^*L%x or other ocular pathologies, such as phthisis bulbi, precluding
F^Bk @ any view of the lens. The posterior segment was examined
}2Tq[rl~s with a direct ophthalmoscope, also through an
33; '6/ undilated pupil.
TF9A4 A cause of vision loss was determined for each eye with
Zrp-Hv27,, a presenting visual acuity worse than 6/18. In the absence of
UVXSW*$ any other findings, uncorrected refractive error was considered
mFeR
~Bi>! to be that cause if the acuity then improved to better
TB-dV'w than 6/18 with pinhole. Other causes, including corneal
,Js-'vX opacity, cataract and diabetic retinopathy, required clinical
,,!P-kK$ findings of sufficient magnitude to explain the level of vision
SU1N*k#-o loss. Although any eye may have more than one condition
c/igw+L() contributing to vision reduction, for the purposes of this
$s4.Aj study, a single cause of vision loss was determined for each
2W2T eye. The attributed cause was the condition most easily
lXZ*Pb<j treated if each of the contributing conditions was individually
0n'vF&E8
treatable to a vision of 6/18 or better. Thus, for example,
|}.}q when uncorrected refractive error and lens opacity coexisted,
S~hu(x# refractive error, with its easier and less expensive treatment,
.rITzwgB was nominated as the cause. Where treatment of a condition
wZN_YFwQ present would not result in 6/18 or better acuity, it was
H\qZu%F' determined to be the cause rather than any coincident or
7BL)FJ]UR] associated conditions amenable to treatment. Thus, for
SZyORN example, coincident retinal detachment and cataract would
vS
)>g4 be categorized as ‘posterior segment pathology’.
*c [^/
Participants who were functionally blind (less than 6/60
xQ7U$QF|] in the better eye) because of unoperated cataract were interrogated
nJGs ,~" about the reasons for not having surgery. The
0Sz[u\w responses were closed ended and respondents had the option
NPrLM5 of volunteering more than one barrier, all of which were
CGzu(@dd\ recorded in a piloted proforma. The first four reasons offered
~!!\#IX were considered for analysis of the barriers to cataract
A= 5Ebu!z surgery.
7KX27.~F Those eyes previously operated for cataract were examined
! xG*W6IT to characterize that surgery and the vision outcome. A
jS~Pdz detailed history of the surgery was taken. This included the
=u ?aP}zc age at surgery, place of surgery, cost and the use of spectacles
9O:l0
l afterward, including reasons for not wearing them if that was
($kw*H{Ah^ the case.
(/N&_r4x The Rapid Assessment of Cataract Surgical Services data
4k-Ak6s entry and analysis software package was used. The prevalences
pITF%J@_] of visually significant cataract, unoperated blinding
Dr
kTM< cataract and cataract surgery were determined. Where prevalence
R-j*fO} estimates were age and gender adjusted for the population
/De~K+w7o of PNG, the estimated population structure for the
P|bow+4 882 Garap
0Zi+x
#&d et al.
%&yPl{ © 2006 Royal Australian and New Zealand College of Ophthalmologists
*>KBDFI year 2000
twq~.:<o 1
(+epRC was used, and 95% CI were derived around these
v={{$=/t point estimates. Additional analysis for potential associations
Vv}R
S@4U of cataract, its surgery and surgical outcomes employed the
o#e8
Piw STATA (version 8.0; StataCorp LP, TX, USA). Fisher’s exact
+h4W<YnW test and the chi-square test for bivariate analysis and a multiple
#~|k EGt logistic regression model for multivariate analysis were
5b7(^T^K used. Odds ratios (OR) and 95% CI were estimated. A
{h7 vJ^ P
{:K
_=IRZ -
L^
J|cgmNw value of
7;fC
%Fq <
{fzX2qMZ] 0.05 was taken as significant for this analysis.
j)mU`b_ The Cataract Surgical Coverage (Eyes) (CSC(Eyes)) was
9kH~=`: ? calculated. This is a surgical service impact indicator. It measures
U`ttT5;
the proportion of cataract that has been operated on
/'rj L<M in a defined population at a particular point in time, being
h#hr'3bI1 the eyes having had cataract surgery as a percentage of the
#T_!-;(Z combined total of all of those eyes operated with those
RW. qw4 currently blind (less than 6/60) from cataract (CSC(Eyes) at
&-yRa45? 6/60
h9H z6
> =
5qtk#FB 100
iWf+wC| a
3\XNOJH /(
[<RhaZz a
/grTOf
& +
4^L;]v,|7 b
Dt:
Q$ ), where
avRtYL a
Vke<; k- =
1&=)Bxg4 pseudophakic
Z!"-LQJ +
&j F'2D^_ aphakic eyes,
hJEd7{n and
@Lnv b
%;'~TtW5 =
'Cc~|gOgD eyes with worse than 6/60 vision caused by cataract).
"]S 8
s:3[#&PQpN The Cataract Surgical Coverage (Persons) (CSC(Persons))
&>JP.//spi was determined. This considers people with operated
lx:$EJ cataract (either or both eyes) as a proportion of those having
}(nT(9| operable cataract. (CSC(Persons) at 6/60
xuK"pS
=
V"YeF:I 100(
f$C{Z9_SX x
JQ03om--( +
#r'MfTr y
uHg q"e )/
B0@
Tz39= (
Jl{ 0q7b x
<fUo@]Lv
+
U~x]2{} y
PQ&*(G +
EF`}*7) z
RA0;f'"` ), in which
+{:uPY#1 x
gNCS*a =
=
lo.LFV persons with unilateral pseudophakia
xKUL}>8 or unilateral aphakia and worse than 6/60 vision
5BVvT
`< caused by cataract in the other eye,
sINQ?4_8T y
NM3;l}Y8 =
4aXIRu%#7 persons with bilateral
=-U0r$sK+F previously operated cataract, and
!d72f8@9 z
FLi'}C =
x92^0cMf persons with bilateral
l2
.S^S cataract causing vision worse than 6/60 in each).
1VJ${\H] 8
;R?@
D] The Cataract Surgical Rate, being the number of cataract
hYJzF.DW<$ operations per year per million of population, was also
}3#\vn0gT estimated.
&;@L]
o R
_Y; TS1u ESULTS
CFbNv9GZj Of the 1191 people enumerated, 5 subjects were not available
]\pi!oa during the survey and 12 refused participation. Data
^')8-aF
. from these 17 were not considered in the analysis. Of the
t1 3V>9to remaining 1174 (98.6%), 606 (51.6%) were female, and 914
yv,FzF}7 (77.9%) were domiciled in rural Rigo.
(?4%Xtul1 Cataract caused 35.2% of vision impairment (presenting
5JzvT JMx vision less than 6/18) and 62.8% of functional blindness
'/>Mr!H# (presenting vision less than 6/60) in the 2348 eyes sampled
sfXFh (Table 1). It was second to refractive error (45.7%)
P $`
1} 7
OUBGbld in the
JxVGzb`8 former, and the leading cause of the latter.
@)Vpj\jM-C For the 1174 subjects, cataract was the most prevalent
7#LIG r cause of vision impairment (46.7%) and functional blindness
CNNqS
^ct (75.0%) (Table 1). On bivariate analysis, increasing age
@O#!W]6NT6 (
,.)wCZ,wca P
o#qdgZ <
x{R440" 0.001), illiteracy (
E+L
7[ P
#T)Gkc"{ <
T@W:@,34 0.001) and unemployment
R~g|w4a@sC (
\+o\wTW P
Clf$EX;~ <
T<]{:\*n 0.001) were associated with cataract-induced functional
XFhH+4#] blindness. Gender was not significantly associated (
*V&M5 P
{it.F4. =
MdBmq/[O 0.6).
vj?{={Y In a multivariate model that included all variables found
!U`4 significant in bivariate analysis, increasing age (reference category
.tRm1&Qi 50–59 years; OR: 2.6, 95% CI: 1.6, 5.9 for persons
vobC/m aged 60–69, OR: 9.8, 95% CI: 4.6, 20.6 for persons aged
*BKD5EwS 70–79, and OR: 18.6, 95% CI: 8.3, 41.9 for persons aged
8\{!*?9! 80 years and older) and illiteracy (OR 2.2, 95% CI 1.3, 3.8)
3 Zp<# were associated with functional cataract blindness.
Qa2h#0j The survey sample included 97 people (8.3%) who had
>LPb>t5%p previously undergone cataract surgery, for a total of 136 eyes
hb3n-
rO (5.8%). On bivariate analysis, increasing age (
w
UvE P
JA^!i98{ =
^;
K
CE 0.02), male
ZA=J`->k gender (
I"&cr>\ P
-VohU-6 | =
Jt$YSp=!! 0.02), literacy (
`}Y)l:G*g P
x}2nn)fdZ <
(MXy\b
< 0.001) and employed status
..yV=idI (
!oyo_h P
hk
!=ZE3 =
t'K+)OK 0.03) were associated with cataract surgery. Illiteracy
bqn(5)% { was significantly associated with reduced uptake of cataract
]*NYuEgc surgery (adjusted OR 0.43, 95% CI: 0.20, 0.91) in a multivariate
Q7x[08TI model that adjusted for age, gender and employment
K qJE?caw status.
,X/j6\VBO The CSC(Eyes) at 6/60 for the survey sample was
^mC~<pP( 34.5%, and the CSC(Persons) at the same vision level was
|
0ZJ[[2 45.3%.
bB4FjC': Most cataract surgery occurred in a government hospital
jNxTy UU (
#GGa, @O P
}wo:1v8J <
RrxbsG1HP 0.001), more than 5 years ago (
D@p{EH P
`N[@lV\xp! <
cPcH
8Vd 0.001). Also, most
DWtITO> of the intracapsular extractions were performed more than
KS#A*BRQ 5 years ago (
}S iR;2W P
9ug4p'
] <
/- Gq`9Z 0.001). Patients are now more likely to
,~7~ S" receive intraocular lens surgery (
'-myOM7 P
\i?bt0 bM <
~> )>hy) 0.001). Although most
7&