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NR 1-3/2009
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Incidence and
functional outcome of phacoemulsification complicated by
posterior capsular rupture
Wyniki czynnościowe
fakoemulsyfikacji zaćmy powikłanej pęknięciem torby tylnej
soczewki
Wilczyński Michał, Wilczyńska Olena,
Synder Aleksandra, Omulecki Wojciech
1st Chair and Department of Ophthalmology, Medical University of
Lodz
Head: Professor Wojciech Omulecki, MD, PhD |
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| Summary: |
Purpose: To
evaluate retrospectively anatomic and functional results
of phacoemulsification with posterior chamber
intraocular lens implantation, complicated by
intraoperative posterior capsular rupture (PCR).
Material and methods: Data were gathered from
medical records of 930 patients (one thousand eyes), who
underwent phacoemulsification. The examined group
consisted of 52 eyes of 52 patients, 27 women (52%), and
25 men (48%), 50 to 84 years old (mean age 73.52 ± 7.8),
who underwent phacoemulsification complicated by
intraoperative posterior capsular rupture.
The control group consisted of 427 patients, including
263 women (61.59%) and 164 men (38.41%), at the age 44
to 93 (mean age 70.3 ± 10.2), who underwent
uncomplicated cataract phacoemulsification.
All patients had ophthalmic examination preoperatively,
one day postoperatively and 10 to 14 days
postoperatively. The evaluated data included: patients’
age and gender, pre- and postoperative best corrected
visual acuity, intraocular pressure, state of the
anterior and posterior segment, early postoperative
complications, type of implanted intraocular lens and
whether anterior vitrectomy was performed. Nonparametric
tests were used for statistical analysis (Wilcoxon
signed-ranks test and Mann-Whitney U test).
Results: A statistically significant difference
in postoperative BCVA between both groups was found.
Mean postoperative BCVA in the PCR group was 0.63 ±
0.27, whereas mean postoperative BCVA in the reference
group was 0.78 ± 0.18 (p<0.001). Ten patients in the PCR
group (19%), required anterior vitrectomy.
In-the-bag implantation was performed in all eyes from
the reference group, but it constituted only 31% (16
eyes), of the PCR group. We found that eyes with PCR are
2.6 times more likely to develop other intraoperative
complications and early postoperative complications in
comparison with controls. In our study eyes with PCR
were about 5 times more likely to have a final BCVA
worse than 0.5 than eyes from uncomplicated surgery
group.
Conclusions: Eyes with intraoperative PCR during
phacoemulsification have a higher risk of reduced BCVA,
however, it is possible to achieve good final BCVA in
the majority of eyes. Appropriate intraoperative and
postoperative management will usually allow to perform a
successful procedure with safe placement of an
intraocular lens, thus ensuring a relatively favourable
outcome. |
| Słowa kluczowe: |
cataract,
phacoemulsification, outcome, complications, posterior
capsular rupture, vitreous loss. |
| Key words: |
zaćma, fakoemulsyfikacja,
wyniki, powikłania, pęknięcie torby tylnej soczewki |
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Introduction
From time to time every cataract surgeon will encounter some
complications in his practice. Posterior capsular rupture (PCR)
is a relatively frequent and significant complication that most
surgeons have to face, especially during the learning period.
Its incidence decreases with the increasing experience of the
surgeon, however, PCR is sometimes encountered even by the most
experienced ophthalmologists. Capsular rupture is a recognised
risk factor of cystoid macular oedema and retinal detachment,
and therefore it is a risk factor of reduced final postoperative
visual acuity (1,2,3).
We have retrospectively examined a consecutive series of
patients undergoing phacoemulsification complicated by PCR and
compared the results with a reference group with intact
posterior capsule.
The purpose of the study was to retrospectively evaluate
anatomic and functional results of phacoemulsification of
cataract with intraocular lens implantation, complicated by
intraoperative posterior capsular rupture.
Materials and methods
The evaluated data were gathered from medical records of 930
patients (one thousand eyes),who underwent phacoemulsification
of cataract between June 2002 and June 2003 in the Department of
Ophthalmology, Medical University of Lodz, Poland. All surgeries
were performed by two experienced surgeons.
We reviewed manually 930 case histories in order to extract data
for further evaluation. In order to eliminate the influence of
co-morbidity on the results, patients with history of other
present or previous ocular disease, previous intraocular
surgery, as well as patients undergoing combined procedures were
excluded from the study. We have found 52 eyes with
intraoperative posterior capsular rupture (PCR), in the records,
which constitutes 5.2% of all reviewed patient documentation.
All patients from both groups were operated using a “Divide and
Conquer” technique with an Oertli phaco machine, utilising a
peristaltic pump. All patients were operated under local (peribulbar)
anaesthesia.
The examined group (Group I), consisted of 52 eyes (52 patients),
including 27 women (52%) and 25 men (48%), at the age ranging
from 50 to 84 years old (mean age 73.5±7.8), who underwent
phacoemulsification complicated by intraoperative posterior
capsular rupture.
All patients from Group I had a scleral tunnel incision 5.5mm to
6.0mm wide, which was closed with a cross-running suture. All
patients received a one-piece rigid all-PMMA intraocular lens.
None of the patients from this group had any intraocular surgery
in this eye before, nor did they have any coexisting ocular
disease.
The control group (Group II) consisted of all patients who
underwent uneventful surgery, who were operated in the same
period using the same technique as patients from PCR group. For
this reason, this group was much larger and consisted of 427
patients, including 263 women (62%) and 164 men (38%), at the
age 44 do 93 (mean age 70.3 ± 10.2).
All patients from the control group underwent uncomplicated
cataract phacoemulsification through a 5.5mm or 6.0mm wide
scleral tunnel closed with a cross-running suture, with a
one-piece rigid all-PMMA intraocular lens implanted in-the-bag
and had intact posterior capsule. Patients from this group have
never had any intraocular surgery in this eye before, they also
did not have any coexisting ocular disease.
The difference in numbers of analysed cases between both groups
arises from the fact that all patients without co-morbidity, who
were operated in the same period with the same technique using
the same equipment were included in the study. All patients had
ophthalmic examination preoperatively, one day postoperatively
and 10 to 14 days postoperatively. The evaluated data included:
patients’ age and gender, pre- and postoperative best corrected
visual acuity (BCVA), intraocular pressure, state of the
anterior and posterior segment, early postoperative
complications and type of implanted intraocular lens. We also
noted whether anterior vitrectomy was performed. Patients
undergoing combined procedures were excluded from the study.
Nonparametric tests were used for statistical analysis.
Calculations were performed for the level of significance α =
0.05 using Microsoft Excel software. Changes of pre- and
postoperative values in the same group were compared using
Wilcoxon signed-ranks test and statistical significance between
two groups was determined using Mann-Whitney U test.
Results
Figure 1 shows pre- and postoperative best corrected visual
acuity in both groups. There was a significant postoperative
increase in BCVA in both groups (Wilcoxon T test: PCR group
p<0.0001, the reference group p<0.0001). We also found a
significant difference in preoperative BCVA between the groups (Mann-Whitney
U test: p<0.05). Mean preoperative BCVA in the PCR group was
0.20 ± 0.19 whereas mean preoperative BCVA in the reference
group was 0.26 ± 0.21. Despite apparent similarity, the
difference proved to be significant.
In the PCR group BCVA improved in 45 eyes (86.5%), did not
change in 5 eyes (9.6%) and decreased in 2 eyes (3.9%). The two
eyes with decreased postoperative BCVA were: one eye with
retinal detachment and one eye after vitreous loss and anterior
vitrectomy where BCVA decreased from 0.3 before the surgery to
0.1 postoperatively due to cystoid macular oedema. In the
reference group BCVA improved in 412 eyes (96.5%) and did not
change in 15 eyes (3.5%). There were no cases of postoperative
decrease of BCVA in this group.
Moreover, we observed a statistically significant difference in
postoperative BCVA between both groups (Fig. 1). Mean
postoperative BCVA in the PCR group was 0.63 ± 0.27 whereas
mean postoperative BCVA in the reference group was 0.78 ± 0.18 (Mann-Whitney
U test: p<0.001) (Fig. 2). Within the PCR group, mean BCVA of
the subgroup with anterior chamber implant was 0.61 ± 0.29. BCVA
of patients from the PCR group who received posterior chamber
lens was not significantly different and amounted to 0.64 ± 0.26
(Mann-Whitney U test: p>0.5).
All patients from the reference group had their IOLs implanted
in-the-bag. In contrast, in-the-bag implantation constituted
only 30.77% (16 eyes) of the capsular rupture group. Further 27
patients of this group (51.92%) had the IOL implanted to the
ciliary sulcus. The rest of the group (9 eyes, 17.31%) received
an anterior chamber lens. None of the eyes was left aphakic
(Tab. I).
In the PCR group there were 10 patients (19%) requiring
mechanical anterior vitrectomy, the rest did not have vitreous
loss requiring this procedure. Anterior vitrectomy was not
performed in any patient from the reference group. Two patients
(4%) from the PCR group had an intraoperative pupillary miosis,
in 4 patients (8%) the pupil margin was slightly damaged by the
phaco tip, in 1 patient (2%) the surgery was complicated by a
dropped nucleus and in 1 patient there was a vitreous
haemorrhage.
In the reference group 1 patient (0.002%) had an intraoperative
iris contraction, which however was remedied by the use of iris
hooks (retractors), and did not prevent the surgeon from
performing a successful procedure. There were no other
intraoperative complications in this group.
Postoperatively, in the PCR group 20 patients (38.5%) had
Descemet membrane folds (including 8 patients -15.4%), who
additionally had transient corneal oedema, 2 patients (3.9%) had
trace of dispersed blood in the anterior chamber, 2 patients
(3.9%) had fibrinoid reaction in the anterior chamber. There was
transient intraocular pressure rise in 1 eye (2%), cystoid
macular oedema in 1 eye and retinal detachment in 1 eye.
In the reference group Descemet folds were present in 42
patients (9.8%), transient corneal oedema was found in 23
patients (5.4%), trace of dispersed blood in the anterior
chamber in 4 eyes (0.9%), wound dehiscence in 1 eye (0.2%),
fibrinoid reaction in the anterior chamber in 2 eyes (0.5%),
corneal epithelium abrasion in 1 eye (0.2%), transient
intraocular pressure rise in 2 eyes (0.5%). There were no cases
of endophthalmitis in any group.
In total, some form of early postoperative complications were
present in 51.9% of eyes from the PCR group (27 eyes) and in
18.5% of eyes from the reference group (79 eyes).
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Discussion
Minimised manipulations, use of viscoelastic devices, and gentle
hydrodissection may help to avoid capsular rupture. It is
thought that posterior capsule may be weaker in posterior polar
cataracts, myopic eyes and eyes with pseudoexfoliation syndrome
(4). In such patients posterior capsular rupture may result
solely from hydrodissection, so it must be performed gently and
carefully. In eyes with a shallow anterior chamber, placing the
second instrument behind the nucleus may help prevent the phaco
tip from contacting the posterior capsule. In eyes with a
capsular tear, the surgeon may either try to perform
phacoemulsification with extreme care or convert to an
extracapsular technique. In such cases ultrasound of low-energy,
low aspiration and low irrigation may be significant factors
reducing the risk of nuclear loss, collapse of the anterior
chamber and vitreous prolapse (1).
To date, there have been a few studies evaluating visual outcome
in cases with posterior capsule rupture, describing various
results. In our data, we found a similar incidence of PCR
(5.2%), than in previously published studies (4-18%) (2,5). In
our group we found that in the vast majority of eyes (87%) from
the PCR group postoperative BCVA was better than preoperatively,
despite the fact that intraoperative and early postoperative
complications occurred. In the literature, some authors have
found a generally good visual outcome after PCR, with a similar
rate of postoperative improvement in BCVA (5,6,7), however some
others found PCR to be a significant risk factor of decreased
final visual acuity (8).
The observed slight difference in preoperative BCVA between the
groups (with a worse preoperative mean BCVA in the PCR group),
most probably reflects more advanced cataract in the PCR group,
which suggests that more advanced cataract may be a risk factor
of PCR.
We observed that ciliary sulcus was the site chosen the most
frequently for the IOL implantation in eyes with PCR. In very
large complicated capsular tears when neither in-the-bag, nor
sulcus placement of the IOL is safe, it is possible either to
leave the eye aphakic (for secondary IOL implantation in the
future), to implant the lens to the anterior chamber or to use a
sclerally fixated posterior chamber lens. In our data, we found
1 patient from Group I with a dropped nucleus, who was
subsequently successfully treated with pars plana vitrectomy,
phacoemulsification of luxated lens in the vitreous cavity and
implantation of the sclerally fixated IOL (1).
We also found that in our study vitreous loss requiring anterior
vitrectomy was present in nearly one fifth of the PCR group,
however, according to some other studies this percentage may be
as high as 58% (5).
We found that eyes with PCR are about 2.6 times more likely to
develop other intraoperative complications and early
postoperative complications in comparison with controls. It is
worth noting that in our study eyes with posterior capsular
rupture were about 5 times more likely to have a final best
corrected visual acuity worse than 0.5 than eyes from
uncomplicated surgery group (21% vs. 4%). Nevertheless, our
observations confirm that it is possible to achieve good final
best corrected visual acuity in the majority of eyes with PCR
(79% of eyes with PCR had final BCVA 0.5 or better). This is
consistent with data from other studies claiming percentage of
BCVA better than 0.5 equal to 84.5% (5).
Moreover, we recognise that our observations of patients were
cut-off at discharge from hospital service to primary care
ophthalmologists, therefore we do not have data regarding late
postoperative complications.
Eyes with intraoperative posterior capsule rupture during
phacoemulsification have a higher risk of reduced visual acuity,
however, in cases where posterior capsule rupture occurs it is
possible to achieve good final best corrected visual acuity in
the majority of eyes with PCR. Appropriate intraoperative and
postoperative management will usually allow to perform a
successful procedure with safe placement of an intraocular lens,
thus ensuring a relatively favourable outcome.
Although in our department scleral tunnel incisions were
replaced by small clear corneal incisions (including MICS
technique), with foldable IOLs implantation, we believe that
this study is valuable as a retrospective analysis of results
and complications in cases of posterior capsular rupture.
This study was presented at the XXIV Congress
of the European Society of Cataract and Refractive Surgeons,
held on the 07-13.09.2006 in London, UK.
References:
1. Steinert RF, Cionni RJ, Osher RH, Blumenkranz MS, Koch DD,
Novak KD et al.: Complications of Cataract Surgery (in:)
Albert D. M., Jakobiec F. A: Principles and Practice of
Ophthalmology, 2nd edition, W. B. Saunders Company, Philadelphia,
2000.
2. Yap EY, Heng WJ: Visual outcome and complications after
posterior capsule rupture during phacoemulsification surgery.
Int Ophthalmol 1999, 23, 57-60.
3. Onal S, Gozum N, Gucukoglu A: Visual Results and
Complications of Posterior Chamber Intraocular Lens Implantation
After Capsular Tear During Phacoemulsification. Ophthalmic Surg
Lasers Imaging 2004, 35, 219-224.
4. Osher R, Yu B, Koch D: Posterior polar cataracts: A
predisposition to intraoperative posterior capsular rupture. J
Cataract Refract Surg 1990, 16, 157-162.
5. Karp KO, Albanis CV, Pearlman JB, Goins KM: Outcomes of
temporal clear cornea versus superior scleral tunnel
phacoemulsification incisions in a university training program.
Ophthalmic Surg Las 2001, 32, 228-232.
6. Osher RH, Cionni RJ: The torn posterior capsule: its
intraoperative behavior, surgical management and intraoperative
consequences. J Cataract Refract Surg 1990, 16, 490-494.
7. Spigelman AV, Lindstrom RL, Nichols BD et al.: Visual results
following vitreous loss and primary lens implantation. J
Cataract Refract Surg 1989, 15, 201-204.
8. Ionides A, Minassian D, Tuft S: Visual outcome following
posterior capsule rupture during cataract surgery. Brit J
Ophthalmol 2001, 85, 222-224.
The study was originally received: 21.11.2008 (1098)/
Praca wpłynęła do redakcji 21.11.2008 r. (1098)
Accepted for publication: 21.01.2009/
Zakwalifikowano do druku 21.01.2009 r.Adres do
korespondencji (Reprint requests to):
dr n. med. Michał Wilczyński
I Katedra i Klinika Chorób Oczu
Uniwersytetu Medycznego w Łodzi
Szpital Kliniczny Nr 1 im. N. Barlickiego
ul. Kopcinskiego 22
90-153 Łódź
e-mail:
michalwilczynski@wp.pl
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Fig. 1. Pre- and postoperative best corrected
visual acuity in both groups.
Ryc. 1. Ostrość wzroku z najlepszą korekcją przed zabiegiem i po
zabiegu w obu grupach.
Fig. 2. Pre- and postoperative best corrected
visual acuity in PCR group, depending on the IOL placement.
Ryc. 2. Ostrość wzroku z najlepszą korekcją przed zabiegiem i po
zabiegu w grupie z pęknięciem torebki, w zależności od miejsca
wszczepu soczewki.
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| N (%) |
PCR group/
Grupa
badana |
Reference group/
Grupa porównawcza |
In-the bag implantation/
wszczep dotorebkowy |
16 (31%) |
427 (100%) |
Ciliary sulcus/ wszczep
do bruzdy ciała rzęskowego |
27 (52%) |
0 |
Anterior chamber implant/
wszczep przedniokomorowy |
9 (17%) |
0 |
Tab. I. Site of IOL implantation.
Tab. I. Miejsce wszczepienia soczewki wewnątrzgałkowej.
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