1. Intraocular lens (IOL) Dislocation
M.R. Akhlaghi MD

2. IOL dislocation Incidence
Intraocular lens (IOL) dislocation has been reported to occur in 0.2% to 1.8% of patients after cataract surgery

3. IOL dislocation Causes:
Main cause is sub optimal posterior capsule supports during or early post operative

4. IOL dislocation Causes:
During operation:
Unknowingly placement
Misjudging haptic placement
Misjudging capsule support
At least 180 degree of a substantially broad rim of post. capsule at least half of which is in the interior quadrant is necessary for satisfactory PC IOL support.

5. IOL dislocation Causes:
Days of weeks after surgery:
Spontaneously IOL haptic rotation
Zonolar dehiscent

6. IOL dislocation Causes:
Months or years after surgery
Trauma
Spontaneously loss of zonolar support. (PEX), Marfan syn.

7. IOL dislocation Evaluation:
Degree of lens malposition
Accompanying complications
Symptoms

8. IOL dislocation Evaluation:
Degree of lens malposition
Mild: the optic covering more than ½ pupilary space
Moderate: the optic covering less than ½ pupillary space
Subluxated: open pupillary space but
in the anterior vitreous
Luxated: completely dislocation

9. IOL dislocation Evaluation:
Symptom & signs is related to degree of malposition:
Glare : related to edge of the IOL optic
Induced astigmatism
Decreased VA
Monocular Diplopia
Floater like symptoms: in luxated & complete mobile IOL
Pupillary block glaucoma: in luxated & complete mobile
Retinal trauma (in luxated & complete mobile)

10. IOL dislocation Evaluation:
Accompanying complications
Inflammation
increased IOP
Vitreous incarceration
Retinal damage
CME

11. IOL dislocation management:
The best approach must be determined individually and is based on factors such as clinical circumstances and coexisting complications
Methods (non surgical, surgical)
Time of surgery
Method of surgery

12. IOL dislocation management:
Non surgical management
Observation is usually recommended for IOLs with simple decentration
If aphakic contact lens correction is satisfactory,
If systemic or ocular problems prohibit further Surgery
If the patient simply elects not to pursue further surgery

13. IOL dislocation management
surgical management
Usually non surgical methods is not satisfactory or convenient to the most of patients

14. IOL dislocation Surgical management:
Indications
decreased VA
persistent CME
Increased IOP and inflammation
coexisting RD
Retain lens material
monocular diplopia
halo phenomenon
fluctuating vision caused by shifting IOL

15. IOL dislocation Time of Surgical management
Optimal time for intervention
intraoperative IOL dislocation:
IOL dislocation days after operation:
dislocations occurring distantly:

16. IOL dislocation surgical management:
IOL removal
IOL exchange
IOL repositioning
Secondary IOL

17. IOL dislocation surgical management:
Surgical approach
Limbal incision: in moderate decentration or subluxated if post. capsule is largely intact
Pars plana vitrectomy: In luxated IOL
offer optimal control to achieve the goal of surgery in subluxated IOL specially if posterior migration occurs

18. IOL dislocation surgical management:
IOL removal RD
Inflammation
Trauma
IOL removal with or without exchange is usually performed for IOLs with damaged haptics, small optics, or highly flexible haptics unsuitable for suture support

19. IOL dislocation surgical management:
IOL exchange
Risk of endothelial cell trauma
Explantation & reimplantation may risk more corneal endothelial trauma compared with repositioning
Exchange for an AC.IOL causes less trauma to endothelial compared with PC IOL placement

20. IOL dislocation surgical managment:
IOL Repositioninig
Most common elected approach
Three basic approaches
In the residual bag or sulcus
iris suture fixation
Scleral fixation
Repositioning a PC IOL in AC may induce chronic iritis, inflammation, and corneal decompensation.

21. IOL dislocation surgical managment
Secondary IOL:
(AC,PC) without explanation of dislocation IOL only in unusual circumstances

22. IOL dislocation Outcomes & complications
Final outcomes depends on
preoperative macular function
Post operative complication of original cataract surgery (CME & RD)
Complication of final operation

23. IOL dislocation Outcomes & complications
In some studies
VA > 20/ %
Initial coexisting RD 0-10%
combined rate of RD 0-16%

24. IOL dislocation Recommendation
Anterior vitrectomy (avoid vitreous incarceration)
A second IOL should not be placed
Frequent topical steroids
If indicated IOP-reducing agent
Vitreoretinal refferal
Careful attention to detect other complications