Posterior segment Intra-Ocular Implant (IOL) dislocation: Predisposing factors, surgical management, outcome analysis

PURPOSE

To evaluate the predisposing factors, management and visual prognosis of intraocular Lens (IOL) dislocation into the posterior segment.

METHODS

The cases of posterior IOL dislocation from January 2012 to May 2017 at 2 centers were reviewed. Only eyes with dislocations requiring IOL explantation or repositioning were included. Predisposing factors, interval between cataract surgery and IOL dislocation, circumstances of onset, management, and postoperative complications are reported.

RESULTS

72 eyes of 72 patients were included. The mean age was 67.6 years. 47 patients (68%) were men. The mean time interval from cataract surgery to IOL dislocation was significantly shorter in the out-of-the bag group than the in-the-bag IOL dislocation group (3.8 months vs 132 months, P=0.002). Predisposing factors for out-of-the-bag IOL dislocation were mainly capsular rupture and/or zonular dehiscence (83%) after complicated cataract surgery. The predisposing factors for in-the-bag IOL dislocation were high myopia (40%), pseudoexfoliation syndrome (40%), previous vitrectomy (38%), or Marfan syndrome (3%) with uneventful cataract surgery. The type of luxated implant was mainly a 3-piece foldable IOL (50%), followed by foldable one-piece IOL (28%) and a rigid one-piece IOL (17%). Most cases of posterior chamber IOL dislocation occurred spontaneously (80%) without a trigger event. Management consisted of a posterior approach in 24 cases (33%) or an anterior approach in 48 cases (67%), associated with IOL repositioning in 20 eyes (28%), and IOL replacement in 34 eyes (47%). Finally, 18 eyes (25%) were left aphakic. Postoperative complications occurred in 7 cases (9.7%).

CONCLUSIONS

Predisposing factors and time from cataract surgery to IOL dislocation were different for out-of-the bag versus in-the-bag IOL dislocation. Management of IOL dislocation varied considerably, depending on surgeon preference and experience. Surgery for IOL dislocation significantly improved best corrected visual acuity and was associated with a low complication rate.

Toric intraocular lens outcomes with a new protocol for IOL selection and implantation

INTRODUCTION

The published literature on toric intraocular lenses (IOL) reports postoperative refractive cylinder less than or equal to 0.5 D in anywhere from 25% to 100% of implantations with both the Acrysof^® Toric and Tecnis^® Toric IOL, depending upon the article. However, the majority of articles tend to cite rates between 70% and 80%.

PURPOSE

The purpose was to evaluate my personal outcomes for both models of toric IOL, in terms of one-month postoperative refractive cylinder, after implementation of new methods of IOL selection, calculation and implantation.

MATERIALS AND METHODS

The new protocol included measurement of centroid surgically induced astigmatism by vector analysis; calculations using only the Barrett toric calculator, for which the keratometry values were obtained by optical biometry, while the keratometric axes were chosen by visual inspection of the axial topographic map; preoperative marking with the toriCAM cell phone appliance; and corneal incisions performed either manually or with a femtosecond laser. A prospective, observational study was conducted of all consecutive monofocal toric IOL implantations from September 2016 through April 2017. One-month postoperative refractive cylinder was recorded for each eye.

RESULTS

Seventy eyes were implanted with monofocal toric IOL, 31 Acrysof^® Toric and 39 Tecnis^® Toric. Mean postoperative refractive cylinder was 0.48 D (0.00-1.50) for the Acrysof^® Toric group and 0.46 D (0.00-1.00) for the Tecnis^® Toric group. There were no statistically significant differences in postoperative refractive cylinder between IOL models or methods of incision. The percentage of eyes achieving postoperative refractive cylinder ≤0.50 D ("success") was 77% for the Acrysof^® Toric group (82% for laser-assisted and 75% for manual) and 72% for the Tecnis^® Toric group (80% for laser-assisted and 69% for manual).

CONCLUSION

The implementation of the new protocol resulted in an overall surgical success rate of 77% for Acrysof^® Toric IOL and 72% for Tecnis^® Toric IOL (P=0.7702). Femtosecond laser-assisted surgery resulted in higher success rates than manual surgery (82% vs. 75% for Acrysof^® Toric and 80% vs. 69% for Tecnis^® Toric), but these differences were not statistically significant (Acrysof^® Toric P=0.7336; Tecnis^® Toric P=0.8862).

Impact of lens thickness on complications of hypermature cataract surgery: A prospective study

PURPOSE

To assess the correlation between lens thickness (LT) measured by ultrasonography and duration of surgery as well as complications.

SETTING

The study was conducted in a hospital in the Parisian suburb of Bobigny, France.

DESIGN

A prospective and monocentric study was conducted. All patients undergoing surgery for hypermature cataract between January 2013 and March 2014 were included.

METHODS

Morphological features, including LT, axial length, anterior chamber depth and vitreous length were assessed using A-scan ultrasonography. The other parameters assessed were the duration of surgery, occurrence of complications during surgery, visual acuity (VA) and corneal edema score one week after surgery.

RESULTS

Thirty eyes of 29 patients were included. Mean LT was 4.11±0.64mm (median: 3.89mm). Mean surgery duration was 24.2±8.7min. Three patients experienced complications during surgery: 2 capsular breaks and 1 posterior lens dislocation. At one week, the mean decimal VA was 0.49±0.34 and the mean corneal edema score was 0.76±1.09. The Pearson correlation coefficient was r=0.27 (P>0.05) between LT and surgery duration while it was r=-0.53 (P=0.01) between VA and LT. No correlation was found for the other parameters studied.

DISCUSSION

In this study, the linear correlation between LT and the surgery duration was low. The visual recovery at day 7 appeared inversely correlated with the LT.

CONCLUSIONS

LT did not seem to be a marker for longer surgery duration but appeared related to the visual recovery at one week.

[Femtosecond laser-assisted cataract surgery]

Femtosecond laser-assisted cataract surgery is a major technological innovation. The femtosecond laser, during a pretreatment step, helps to prepare the patient's eye for the surgery proper by creating corneal incisions, anterior capsulotomy and lens fragmentation in an automated fashion. Thus, these steps can be performed with precision and reproducibility, and lens fragmentation reduces the amount of ultrasound required during surgery. Drawbacks of this technology are a longer operating time, a more demanding surgical procedure and a much higher cost for patients and surgical centers. New models of organization in the operating room, patient flow, and financial systems have to be designed to adapt this procedure to our practice. The benefits of this technology should make it an essential tool in the future, provided that cataract surgery can be reconsidered logistically and economically.