ABSTRACT
bTy'5" Purpose: To quantify the prevalence of cataract, the outcomes
65`'Upu of cataract surgery and the factors related to
[&O:qaD^ unoperated cataract in Australia.
^?S@v1~7d Methods: Participants were recruited from the Visual
$=QGua V Impairment Project: a cluster, stratified sample of more than
5 1CU@1Ie 5000 Victorians aged 40 years and over. At examination
@,>=X:7 sites interviews, clinical examinations and lens photography
C&s }m0R were performed. Cataract was defined in participants who
@ !O&b%8X% had: had previous cataract surgery, cortical cataract greater
)hZ}$P1 than 4/16, nuclear greater than Wilmer standard 2, or
!k??Kj posterior subcapsular greater than 1 mm2.
4Z
T Results: The participant group comprised 3271 Melbourne
4kY{X%9 residents, 403 Melbourne nursing home residents and 1473
5SWX v+ rural residents.The weighted rate of any cataract in Victoria
F>_lp,G was 21.5%. The overall weighted rate of prior cataract
Y*X6lo surgery was 3.79%. Two hundred and forty-nine eyes had
RKJWLofX& had prior cataract surgery. Of these 249 procedures, 49
A`U 2HC (20%) were aphakic, 6 (2.4%) had anterior chamber
/$4?.qtu intraocular lenses and 194 (78%) had posterior chamber
uY%3X/^j intraocular lenses.Two hundred and eleven of these operated
S?z j&XY3 eyes (85%) had best-corrected visual acuity of 6/12 or
zB7dCw better, the legal requirement for a driver’s license.Twentyseven
$Qc%9p
@i (11%) had visual acuity of less than 6/18 (moderate
/s0VyUV= vision impairment). Complications of cataract surgery
SD.*G'N&2f caused reduced vision in four of the 27 eyes (15%), or 1.9%
cXEy>U|/ of operated eyes. Three of these four eyes had undergone
Mn{Rg>X intracapsular cataract extraction and the fourth eye had an
['YRY B opaque posterior capsule. No one had bilateral vision
3&d
+U)E impairment as a result of cataract surgery. Surprisingly, no
=&G|} M particular demographic factors (such as age, gender, rural
x=r6vOj residence, occupation, employment status, health insurance
e&7}N Za status, ethnicity) were related to the presence of unoperated
R =c cataract.
(%IstR|u: Conclusions: Although the overall prevalence of cataract is
<6@NgSFz' quite high, no particular subgroup is systematically underserviced
{7s zo`U2 in terms of cataract surgery. Overall, the results of
2/gj@>dt cataract surgery are very good, with the majority of eyes
8l,hP . achieving driving vision following cataract extraction.
aRKG)0= Key words: cataract extraction, health planning, health
yBjWPx? services accessibility, prevalence
'WgwLE_ INTRODUCTION
]
:#IZ0# Cataract is the leading cause of blindness worldwide and, in
Gjh7cm> Australia, cataract extractions account for the majority of all
iiFKt( ophthalmic procedures.1 Over the period 1985–94, the rate
W8rn8Rh of cataract surgery in Australia was twice as high as would be
PG]mwaj]) expected from the growth in the elderly population.1
%),O9*[9 Although there have been a number of studies reporting
} dlNMW the prevalence of cataract in various populations,2–6 there is
3"%44' little information about determinants of cataract surgery in
v0J1%{/xs the population. A previous survey of Australian ophthalmologists
3c6) showed that patient concern and lifestyle, rather
2DQC)Pe+z than visual acuity itself, are the primary factors for referral
:!\./z8v for cataract surgery.7 This supports prior research which has
?P]md9$(+e shown that visual acuity is not a strong predictor of need for
}7v2GfEkM cataract surgery.8,9 Elsewhere, socioeconomic status has
$ wB been shown to be related to cataract surgery rates.10
" <AljgF To appropriately plan health care services, information is
5q>u
}J needed about the prevalence of age-related cataract in the
J[AgOUc community as well as the factors associated with cataract
Uij$
eBN surgery. The purpose of this study is to quantify the prevalence
L+CSF ] of any cataract in Australia, to describe the factors
Z&!$G'X related to unoperated cataract in the community and to
S_6
;e| describe the visual outcomes of cataract surgery.
S22 ;g METHODS
Q+dI,5YF Study population
g5[3[Z(. Details about the study methodology for the Visual
Z%=E/xT Impairment Project have been published previously.11
K-5)Y+| > Briefly, cluster sampling within three strata was employed to
Bnv%W4 recruit subjects aged 40 years and over to participate.
D bJ(N h Within the Melbourne Statistical Division, nine pairs of
jL$X3QS: census collector districts were randomly selected. Fourteen
\266N;JrN nursing homes within a 5 km radius of these nine test sites
i/Z5/(z
F were randomly chosen to recruit nursing home residents.
Mt`.|N;y! Clinical and Experimental Ophthalmology (2000) 28, 77–82
@<L.#gtP Original Article
2]wh1) Operated and unoperated cataract in Australia
_6(=0::x Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
WYL.J5O Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
b`mEnI
VIz n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
9Wn0YIc Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au cW\ 7yZh 78 McCarty et al.
"cx" d: Finally, four pairs of census collector districts in four rural
z,WrLZC Victorian communities were randomly selected to recruit rural
>e%Po,Fg$ residents. A household census was conducted to identify
.:}\Z27-c eligible residents aged 40 years and over who had been a
p[
Es4S}N resident at that address for at least 6 months. At the time of
Bb)J8,LQ the household census, basic information about age, sex,
~n?U{
RmH country of birth, language spoken at home, education, use of
#@G2n@Hj corrective spectacles and use of eye care services was collected.
=0S7tNut Eligible residents were then invited to attend a local
KH-.Z0
2U examination site for a more detailed interview and examination.
TocqoYX{{ The study protocol was approved by the Royal Victorian
+e\u4k {3V Eye and Ear Hospital Human Research Ethics Committee.
Kmtr.]Nj Assessment of cataract
BLRrHaX0 A standardized ophthalmic examination was performed after
r?$\`,; pupil dilatation with one drop of 10% phenylephrine
J0`?g6aY hydrochloride. Lens opacities were graded clinically at the
(/^&3xs9 time of the examination and subsequently from photos using
pP .
the Wilmer cataract photo-grading system.12 Cortical and
${?Px
c{- posterior subcapsular (PSC) opacities were assessed on
5HB4B <2 retroillumination and measured as the proportion (in 1/16)
WJ%b9{< of pupil circumference occupied by opacity. For this analysis,
2b<0g@~X cortical cataract was defined as 4/16 or greater opacity,
rpvm].4 PSC cataract was defined as opacity equal to or greater than
>[#4Pb7_Y 1 mm2 and nuclear cataract was defined as opacity equal to
',.Xn`c or greater than Wilmer standard 2,12 independent of visual
GxBj N7" acuity. Examples of the minimum opacities defined as cortical,
up`6IWlLE nuclear and PSC cataract are presented in Figure 1.
{*: C$"L Bilateral congenital cataracts or cataracts secondary to
f"[C3o2P intraocular inflammation or trauma were excluded from the
F$caKWzny5 analysis. Two cases of bilateral secondary cataract and eight
@?t) UE cases of bilateral congenital cataract were excluded from the
f}fM%0/5 analyses.
2Bx\nLf/
K A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
se?nx7~ Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
]WS 7l@ height set to an incident angle of 30° was used for examinations.
uQ{M<%K Ektachrome® 200 ASA colour slide film (Eastman
Wg#>2)> Kodak Company, Rochester, NY, USA) was used to photograph
+UB. M
the nuclear opacities. The cortical opacities were
a^,Xm(Wb} photographed with an Oxford® retroillumination camera
5-MI7I@l (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
^JH 4:
h film (Eastman Kodak). Photographs were graded separately
d
hh`o\$ by two research assistants and discrepancies were adjudicated
F&ux9zP by an independent reviewer. Any discrepancies
.(! $j-B between the clinical grades and the photograph grades were
vzfWPjpKW resolved. Except in cases where photographs were missing,
+"K
a #Z the photograph grades were used in the analyses. Photograph
t1D6#JP(a grades were available for 4301 (84%) for cortical
}e1f kjWk cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
aK'BC>uFI for PSC cataract. Cataract status was classified according to
aCQAh[T the severity of the opacity in the worse eye.
1X]?-+',. Assessment of risk factors
HG{OkDx]fl A standardized questionnaire was used to obtain information
xse8fGs about education, employment and ethnic background.11
PyK)ks!6 Specific information was elicited on the occurrence, duration
rxt)l and treatment of a number of medical conditions,
(r.[b including ocular trauma, arthritis, diabetes, gout, hypertension
Nvw'[?m and mental illness. Information about the use, dose and
Ubv<3syR' duration of tobacco, alcohol, analgesics and steriods were
"H#2 collected, and a food frequency questionnaire was used to
b{_J%p determine current consumption of dietary sources of antioxidants
it \3- and use of vitamin supplements.
s>ilxLSX] Data management and statistical analysis
(}
?")$. Data were collected either by direct computer entry with a
*6<<6f`( questionnaire programmed in Paradox© (Carel Corporation,
OF-$* Ottawa, Canada) with internal consistency checks, or
O!#r2Y"?K1 on self-coding forms. Open-ended responses were coded at
DgW*Br8< a later time. Data that were entered on the self-coded forms
opc`n}Fc were entered into a computer with double data entry and
BS!VAHO"V reconciliation of any inconsistencies. Data range and consistency
k^K>*mcJ checks were performed on the entire data set.
q8#zv_>K SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
B:;$5PUTc employed for statistical analyses.
gM>geWB< Ninety-five per cent confidence limits around the agespecific
"n'kv!?\ rates were calculated according to Cochran13 to
wwUa+6? account for the effect of the cluster sampling. Ninety-five
ip8%9fG\> per cent confidence limits around age-standardized rates
B63puX{u# were calculated according to Breslow and Day.14 The strataspecific
kn%i#Fz data were weighted according to the 1996
iC2``[m" Australian Bureau of Statistics census data15 to reflect the
;S0Kf{DN2 cataract prevalence in the entire Victorian population.
e|>
5
R Univariate analyses with Student’s t-tests and chi-squared
sBm)D=Kll tests were first employed to evaluate risk factors for unoperated
\w#)uYK{i_ cataract. Any factors with P < 0.10 were then fitted
z;iNfs0i$ into a backwards stepwise logistic regression model. For the
P_}wjz}9ZX Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
duQ,6 final multivariate models, P < 0.05 was considered statistically
[
|A;{F# significant. Design effect was assessed through the use
g
^I
?u$&E of cluster-specific models and multivariate models. The
{f"oq
ry_g design effect was assumed to be additive and an adjustment
7D&O5Z=%+ made in the variance by adding the variance associated with
@B\$
me the design effect prior to constructing the 95% confidence
>)^Q p- limits.
X{Ij30Bmv RESULTS
InA=ty]"_U Study population
F/
o }5H A total of 3271 (83%) of the Melbourne residents, 403
'C7$,H' (90%) Melbourne nursing home residents, and 1473 (92%)
'D'H)J rural residents participated. In general, non-participants did
nD.K*# u not differ from participants.16 The study population was
Yz)+UF, representative of the Victorian population and Australia as
:'2h0
5R a whole.
xL [3R
The Melbourne residents ranged in age from 40 to
[2{2w68D! 98 years (mean = 59) and 1511 (46%) were male. The
qC6@ Melbourne nursing home residents ranged in age from 46 to
6t=)1T
101 years (mean = 82) and 85 (21%) were men. The rural
hx! :F"# residents ranged in age from 40 to 103 years (mean = 60)
f cnv[B..{ and 701 (47.5%) were men.
4&AGVplgF Prevalence of cataract and prior cataract surgery
n"w>Y)C(X) As would be expected, the rate of any cataract increases
4Ss*h,Y dramatically with age (Table 1). The weighted rate of any
6zIK%< cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
Ax6zx Although the rates varied somewhat between the three
:}-VLp4b strata, they were not significantly different as the 95% confidence
cJ\1ndBH limits overlapped. The per cent of cataractous eyes
&z05h<] with best-corrected visual acuity of less than 6/12 was 12.5%
Dtox/ ," (65/520) for cortical cataract, 18% for nuclear cataract
D+u\ORj (97/534) and 14.4% (27/187) for PSC cataract. Cataract
P~84#5R1 surgery also rose dramatically with age. The overall
%Z8wUG weighted rate of prior cataract surgery in Victoria was
=gC% = 3.79% (95% CL 2.97, 4.60) (Table 2).
9"?;H%.
Risk factors for unoperated cataract
(coaGQ@d Cases of cataract that had not been removed were classified
Yfx
?3 as unoperated cataract. Risk factor analyses for unoperated
7)RRCsn cataract were not performed with the nursing home residents
!D!"ftOm as information about risk factor exposure was not
IOa@dUh7a, available for this cohort. The following factors were assessed
n\< uT1n in relation to unoperated cataract: age, sex, residence
^U);MH8 (urban/rural), language spoken at home (a measure of ethnic
i|0!yID0@ integration), country of birth, parents’ country of birth (a
W6RjQ1 measure of ethnicity), years since migration, education, use
&;RBG$t of ophthalmic services, use of optometric services, private
&UVqFo health insurance status, duration of distance glasses use,
3vkzN glaucoma, age-related maculopathy and employment status.
wb%4f6i In this cross sectional study it was not possible to assess the
lk[u level of visual acuity that would predict a patient’s having
/z(d!0_q|v cataract surgery, as visual acuity data prior to cataract
;X:Bh8tEV surgery were not available.
qoZe<jW ( The significant risk factors for unoperated cataract in univariate
0d$LUQ't analyses were related to: whether a participant had
TEbIU8{Y ever seen an optometrist, seen an ophthalmologist or been
N!Xn)J diagnosed with glaucoma; and participants’ employment
KO/#t~ status (currently employed) and age. These significant
J\N
&u# factors were placed in a backwards stepwise logistic regression
}rnu:7 model. The factors that remained significantly related
eep/96G
? to unoperated cataract were whether participants had ever
<<V"4 C2 seen an ophthalmologist, seen an optometrist and been
Ba t@ diagnosed with glaucoma. None of the demographic factors
;2[OI were associated with unoperated cataract in the multivariate
/`t}5U>S_ model.
#ApmJLeCO The per cent of participants with unoperated cataract
@1q
dnU who said that they were dissatisfied or very dissatisfied with
t3*.Bm:^ Operated and unoperated cataract in Australia 79
@LY[kt6o Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
3
lKs>HE0 Age group Sex Urban Rural Nursing home Weighted total
CYsLyk (years) (%) (%) (%)
!|
q19$ 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
?kRx;S+ Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
B,` `2\B 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
Q'Uv5p"X Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
zm_8{Rta} 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
mR|']^!SE Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
fo<nk|i 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
m 0Uu2Z4 Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
:.f(}sCS 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
dp2FC Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
#Fgybokm 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
vg1E@rH|} Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
1uEM;O Age-standardized
6KE64: \; (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
!Q}Bz*Y aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
\5a;_N[Ed their current vision was 30% (290/683), compared with 27%
MM&qLAa"f (26/95) of participants with prior cataract surgery (chisquared,
w}M)]kY 1 d.f. = 0.25, P = 0.62).
iszVM Outcomes of cataract surgery
^`RMf5i1m Two hundred and forty-nine eyes had undergone prior
f1B t6|W% cataract surgery. Of these 249 operated eyes, 49 (20%) were
%6&c3,?U\n left aphakic, 6 (2.4%) had anterior chamber intraocular
0Ca/[_ lenses and 194 (78%) had posterior chamber intraocular
]w]:9w lenses. The rate of capsulotomy in the eyes with intact
UnyJD%a posterior capsules was 36% (73/202). Fifteen per cent of
x4`|[ eyes (17/114) with a clear posterior capsule had bestcorrected
4F!%mMq visual acuity of less than 6/12 compared with 43%
r
jnf30 of eyes (6/14) with opaque capsules, and 15% of eyes
7{V N27Fa_ (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
G*-7}7OAs P = 0.027).
Sg(\+j= The percentage of eyes with best-corrected visual acuity
7p{2&YhB of 6/12 or better was 96% (302/314) for eyes without
qg*xdefQ% cataract, 88% (1417/1609) for eyes with prevalent cataract
y+7A?"s) and 85% (211/249) for eyes with operated cataract (chisquared,
N0YJ'.=8, 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
MEtKFC|p operated eyes (11%) had visual acuities of less than 6/18
jz I,B (moderate vision impairment) (Fig. 2). A cause of this
A8ClkLC;I moderate visual impairment (but not the only cause) in four
V|4k=_- (15%) eyes was secondary to cataract surgery. Three of these
R?:(~ X\ four eyes had undergone intracapsular cataract extraction
#BIY[{! and the fourth eye had an opaque posterior capsule. No one
vfh\X1Ui} had bilateral vision impairment as a result of their cataract
QQ99sy surgery.
Wf&i{3z[ DISCUSSION
O5JG!bGE_F To our knowledge, this is the first paper to systematically
?u{D-by%& assess the prevalence of current cataract, previous cataract
%,udZyO3uR surgery, predictors of unoperated cataract and the outcomes
wNl "y of cataract surgery in a population-based sample. The Visual
hNF, sA Impairment Project is unique in that the sampling frame and
Z}>+!Z high response rate have ensured that the study population is
iv6bXV'N representative of Australians aged 40 years and over. Therefore,
(2/i1)Cq these data can be used to plan age-related cataract
ho6,&Bp8 services throughout Australia.
^!K 8nW{* We found the rate of any cataract in those over the age
lH>6;sE of 40 years to be 22%. Although relatively high, this rate is
6/|"y significantly less than was reported in a number of previous
.1[pO_ studies,2,4,6 with the exception of the Casteldaccia Eye
B_0]$D0
^ Study.5 However, it is difficult to compare rates of cataract
lp5b&I_ between studies because of different methodologies and
w)Y}hlcq cataract definitions employed in the various studies, as well
m8&XW2S as the different age structures of the study populations.
<}AmzeHr+ Other studies have used less conservative definitions of
_;k))K^ cataract, thus leading to higher rates of cataract as defined.
~h444Hp= In most large epidemiologic studies of cataract, visual acuity
&-ZRS/_d> has not been included in the definition of cataract.
l4q7,%G Therefore, the prevalence of cataract may not reflect the
jHc/ EZB actual need for cataract surgery in the community.
V(n3W=#kky 80 McCarty et al.
cONfHl{ Table 2. Prevalence of previous cataract by age, gender and cohort
A
Zv| |8p Age group Gender Urban Rural Nursing home Weighted total
f{#Mc (years) (%) (%) (%)
|(R[5q 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
|1Ko5z Female 0.00 0.00 0.00 0.00 (
.t{?doOT 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
A>}]
=Ii/ Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
F2["Ak NM 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
CV6W)B%Se Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
SP5t=#M6 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
IR*:i{ Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
|-VbJd 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
ktK/s!bgY Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
eR5+1b 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
Hxd^oE Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
^->vUf7PX Age-standardized
k3t2{=&'&x (95% CL) Combined 3.31 (2.70, 3.93) 4.36 (2.67, 6.06) 2.26 (0.82, 3.70) 3.79 (2.97, 4.60)
6c&OR2HGqO Figure 2. Visual acuity in eyes that had undergone cataract
'P~6_BW surgery, n = 249. h, Presenting; j, best-corrected.
WjMP]ND#c Operated and unoperated cataract in Australia 81
N_>}UhZ The weighted prevalence of prior cataract surgery in the
_fANl}Mf: Visual Impairment Project (3.6%) was similar to the crude
{v}jV{'^um rate in the Beaver Dam Eye Study4 (3.1%), but less than the
zs@[!?A, crude rate in the Blue Mountains Eye Study6 (6.0%).
MEn#MT/Cz However, the age-standardized rate in the Blue Mountains
VR0#" Eye Study (standardized to the age distribution of the urban
EM.rO/qcW Visual Impairment Project cohort) was found to be less than
UQ 'U
4q the Visual Impairment Project (standardized rate = 1.36%,
[u2)kH$ 95% CL 1.25, 1.47). The incidence of cataract surgery in
H@WQO]PA Australia has exceeded population growth.1 This is due,
H=k*;' perhaps, to advances in surgical techniques and lens
>w=xGb7 implants that have changed the risk–benefit ratio.
%S<( z5 The Global Initiative for the Elimination of Avoidable
"A?_)=zZ Blindness, sponsored by the World Health Organization,
vXM``| states that cataract surgical services should be provided that
m=<;) ‘have a high success rate in terms of visual outcome and
v+Q#O[ improved quality of life’,17 although the ‘high success rate’ is
|!{BjOAD' not defined. Population- and clinic-based studies conducted
\;A\ vQ[ in the United States have demonstrated marked improvement
{XNu4d9w( in visual acuity following cataract surgery.18–20 We
vv,(ta@t2 found that 85% of eyes that had undergone cataract extraction
q
qYH}%0dz had visual acuity of 6/12 or better. Previously, we have
f V.(v& shown that participants with prevalent cataract in this
g3%t+>$* cohort are more likely to express dissatisfaction with their
7>m#Y'ppl@ current vision than participants without cataract or participants
IczEddt@' with prior cataract surgery.21 In a national study in the
I
-obfyije United States, researchers found that the change in patients’
-j9R%+YW< ratings of their vision difficulties and satisfaction with their
+:d))r=n vision after cataract surgery were more highly related to
jL)aU> kN their change in visual functioning score than to their change
L$x/T3@ in visual acuity.19 Furthermore, improvement in visual function
hGF(E* has been shown to be associated with improvement in
*R>I%?]V3 overall quality of life.22
P"u* bqk A recent review found that the incidence of visually
Nu{RF significant posterior capsule opacification following
,Fg&<Be}Jx cataract surgery to be greater than 25%.23 We found 36%
nx,67u/Pb capsulotomy in our population and that this was associated
ki^[~JS>' with visual acuity similar to that of eyes with a clear
Xb3vvHdI capsule, but significantly better than that of eyes with an
*(d^k; opaque capsule.
cVn7jxf A number of studies have shown that the demand and
AJ:@c7:eS timing of cataract surgery vary according to visual acuity,
,^o^@SI)
degree of handicap and socioeconomic factors.8–10,24,25 We
;Xgy2'3 have also shown previously that ophthalmologists are more
=GM!M@~,Ab likely to refer a patient for cataract surgery if the patient is
~rY<y%K employed and less likely to refer a nursing home resident.7
=4 JVUu~Z In the Visual Impairment Project, we did not find that any
e@^}y4
C particular subgroup of the population was at greater risk of
9i|6 having unoperated cataract. Universal access to health care
2 >xV&