1. Possible Predisposing Factors for In-the-bag Dislocation of Intraocular Lens and Surgical Outcomes of Reposition or Exchange of Dislocated Intraocular Lens
Wan-Soo Kim1, Chang-Kyu Lee2, Jung Hyun Jang2
Haeundae Paik Hospital
Inje university1
Maryknoll Medical Center2
The authors have no financial interest in the subject matter of this poster

2. Subject
To examine the possible predisposing factors for intraocular lens(IOL) dislocation within the capsular bag(in-the-bag dislocation) and to study surgical outcomes of reposition or exchange of IOLs
Design : Retrospective interventional case series
Statistical analysis method
Relative risk
T-test
Significance : P-value < 0.05
본 연구의 목적은 백내장 수술과 관련해 현재 optimal surgical outcome 이라고 볼 수 있는 In-the–bag fixation of IOL 후
late-complication으로 발생한 Decentration/dislocation of IOL의 predisposing factor 및 surgical management
후의 결과를 후향적으로 분석하고자 하는 것입니다

3. In-the-bag Dislocation
Patient Demographics
In-the-bag Dislocation
Group
Control Group†
No. of eyes 39
627
Age (yrs)*
57.2 ± 11.2
58.4 ± 8.9
Time of surgery(months)‡
132.83
( From 5.26 to 238.9)
N/A
Gender
(male / female)
31 / 8
343 / 234
Left / Right
23 / 16
298 / 329
환자의 평균 나이는 57.2세였으며 남녀 성비는 31:8, 좌우비는 23 : 16이었습니다
Table 1. Patient Demographics (Mean ± SD)
† Cases that didn’t occur late onset complications of In-the-bag dislocation of IOL
managed at the Maryknoll Medical Center in 2008
* At time of intraocular lens exchange or reposition surgery
‡ From cataract surgery to visual disturbance symptom onset

4. Outcome index Predisposing conditions Preoperative index
Pseudoexfoliation syndrome
Trauma History
Ophthalmologic underlying disease
Previous vitreoretinal surgery
Surgical trauma
High myopia (Axial length)
Other zonular dehiscence factors
Preoperative index
IOL type
1-piece PMMA
3-piece PMMA
3-piece acrylic
3-piece silicone
Nd:YAG capsulotomy
Presence, interval
Postoperative index
Surgical intervention
Best corrected visual acuity
IOP
Spherical equivalent
Refractive astigmatism

5. Figure 1. Types of dislocated IOL
Result
IOL type
† Time to Surgery
11.3 ± 5.0
7.9 ± 3.6
5.4 ± 4.8
7.5 ±5.6
16.7 ± 4.1
7.7 ± 6.2
Publish 된 journal에 따르면 IOL D/L incidence
1 piece > 3 piece d/t capsule contracture decreasing
Plate-haptic Silicone IOL 은 capsulorhexis contracture를 induce 하여 high risk 에서의 contraindication으로 알려져있다
† At time of intraocular lens exchange or reposition surgery
Figure 1. Types of dislocated IOL

6. Surgical intervention
Nd-YAG capsulotomy
2 case (5.1%)
Interval (procedure to dislocation) : 4.3 ± 3.4 mo.
Surgical intervention
IOL exchange / reposition : 15 / 23 case
1 point / 2 point scleral fixation : 5 / 33 case
Other : 1 case
(Aphakic state in the case of pathologic myopia)

7. Surgical outcome State of In-the-bag IOL dislocation
After IOL exchange
or reposition
P-value*
BCVA
0.47 ± 0.31
0.76 ± 0.34
0.0001
IOP(mmHg)
± 3.70
15.94 ± 2.68
0.003
Spherical equivalent(D)
-1.55 ± 5.40
-2.26 ± 1.26
0.24
refractive astigmatism(D)
-3.36 ±1.14
-1.59 ±1.38
0.22
Table 2. Surgical outcomes (Mean ± SD)
*Analasized by T-test

8. IOL Exchange vs Reposition
Fig. 2 Best corrected visual acuity
Fig. 3 Intraocular pressure
Fig. 4 Corneal astigmatism

9. In-the-bag Dislocation
Predisposing Factors
In-the-bag Dislocation
Pseudoexfoliation
syndrome
8(20.5%)
Previous trauma
5(12.8%)
Status of vitrectomy
4(10.2%)
A long axis
2(5.1%)
Surgical trauma
Unknown
18(46.1%)
All case 39
Table 3. Predisposing Factors

10. Vitreoretinal surgery
3 case : Scleral buckling d/t RRD
Axial length
25.32mm (±2.46)
1 case : pathologic myopia, 34.76mm
Surgical trauma
Iatrogenic radial tear and zonular dialysis during the cataract surgery

11. Relative risk (Case/%)
In-the-bag Dislocation
Control group
Relative risk
(95% CI)
Pseudoexfoliation
syndrome
8(20.5%)
15(2.5%)
10.529
(4.151, )
Previous trauma
5(12.8%)
13(2.1%)
6.946
(1.748, )
Status of vitrectomy
4(10.2%)
22(3.6%)
3.143
(1.027, 9.618)
A long axis
2(5.1%)
21(3.4%)
1.560
(0.352, 6.907)
Surgical trauma
7(1.2%)
4.788
(0.961, )
All case 39
627
Table 4. Relative risk

12. Discussion
Possible major predisposing factor for in-the-bag IOL dislocation are Pseudoexfolication, retinal pigmentosa, the status after vitrectomy and trauma
- Ken Hayashi, Akira Hirata, Hideyuki Hayashi, 2007 by the AAO
Pseudoexfoliation, uveitis, myopia, and other diseases associated progressive zonular weakening and capsular contraction are the predisposing factor of in-the-bag IOL dislocation
- Howard V. Gimbel, MPH, Garry P. Condon, Thomas Kohnen, Randall J. Olson, Ioannis Halkiadakis, JCRS 2005
Sufficiency time is necessary
For considering predisposing factors of dislocation
For clinical manifestations
Surgeons have to
Use techniques thought to be least traumatic to the zonule
describe zonular dehiscence during the surgery if it occurs
최근 In-the-bag IOL D/L의 incidence가 증가하고 있습니다
CCC와 Phaco 가 일반화된 현재 백내장 수술에서 대부분의 숙련된 surgeon들은 발달된 백내장 장비를 통해 zonular에 대한 minimal invasive technique를 통해 성공적인 수술은 하고 있지만 late complication 중의 하나인 IOL D/L 가능성을 배제할 수는 없습니다
본 연구의 술자는 현재 많이 사용되고 있는 one-piece soft IOL을 통한 capsule contracture의 증가 incidence 증가의 중요한 원인으로 생각하고 있습니다. 이를 바탕으로 술자는 특히 앞에서 소개된 high risk factor를 가진 환자에서는 large CCC와 PMMA 3-piece IOL을 통한 zonule stress의 최소화를 권유하고 있습니다