Implantation of retropupillary iris-claw lenses: A review on surgical management and outcomes

Outcomes of retropupillary iris claw lens implantation in patients with intraocular lens dislocation and low (less than 1000 cells/mm2) corneal endothelial cell density

BACKGROUND

Posterior chamber intraocular lens (IOL) dislocation is a common complication of cataract surgery. Dislocated IOLs often require surgical intervention due to the potentially severe risks of leaving this condition untreated. If a patient with extremely low corneal endothelial cell density (ECD) presents with IOL dislocation, the surgeon faces a crucial dilemma of choosing the most optimal surgical treatment option. We sought to investigate the efficacy and safety of retropupillary iris claw intraocular lens (R-IOL) implantation in patients with IOL dislocation and extremely low (< 1000 cells/mm2) ECD.

METHODS

We retrospectively reviewed the medical records of nine patients (all men) whose pre-operative ECD was < 1000 cells/mm2 and who underwent R-IOL implantation due to intraocular subluxation or total dislocation into the vitreous cavity between 2014 and 2020. We evaluated corneal endothelial function and visual outcomes after surgery.

RESULTS

Nine patients were included in this study. The mean age at diagnosis was 64.89 ± 7.15 years (range 57-76 years), and the follow-up duration was 37.93 ± 23.72 months (range 18.07-89.07 months). No patients developed bullous keratopathy during follow-up. Compared to the initial ECD, corneal thickness (CT), coefficient variation of cell area (CV) and percentage of hexagonal cells (HEX), there was no statistically significant decrease in the ECD, CV, and HEX at last follow-up (P = 0.944, 0.778, 0.445, 0.443). There was significant improvement in the mean uncorrected distance visual acuity (UDVA) at the last follow-up (average 0.13 logMAR, 20/27 Snellen) compared to the pre-operative mean UDVA (average 1.09 logMAR, 20/250 Snellen) (P < 0.01).

CONCLUSIONS

R-IOL implantation did not result in a statistically significant decline in corneal endothelial function in patients with preoperatively low ECD, and it significantly improved the mean UDVA postoperatively. R-IOL implantation appears to be a safe and effective treatment modality for intraocular lens dislocation in patients with low ECD (< 1000 cells/mm²); however, long-term follow-up studies are warranted to corroborate these findings.

A new approach for single-haptic retropupillary iris-claw lens subluxation - The "fencing" technique

INTRODUCTION

Single-haptic iris-claw intraocular lens (IOL) dislocation is not an uncommon complication. A few different surgical techniques are available for its refixation but usually involve a more invasive approach. We aim to demonstrate an original and simple approach for refixation of single haptic retropupillary iris-claw IOL subluxations.

METHODS

We present a case of an 80-year-old male with a single haptic retropupillary iris-claw IOL subluxation in a previously vitrectomized eye. We used a new surgical approach to refix this type of subluxation.

RESULTS

This new technique uses only two 30-gauge needles (one of them connected to a viscosurgical device) to re-enclavate the subluxated haptic of the retropupillary iris-claw IOL. By minimising surgical manipulation, the patient's postoperative period was uneventful.

CONCLUSIONS

We highlight a new, quick, safe, and unusual surgical approach to single-haptic retropupillary iris-claw IOL dislocation in vitrectomized eyes. Because of its characteristics, we named it the "fencing" IOL repositioning technique.

Scleral-fixated vs Iris-fixated intraocular lens in pediatric ectopia lentis: A systematic review

Numerous intraocular lens (IOLs) options are available for treating pediatric ectopia lentis, and this paper reviews recent literature on pediatric ectopia lentis treatment with iris-fixated and scleral-fixated IOLs. A comprehensive search was undertaken on PubMed, Embase, ProQuest, Cochrane, Wiley, SCOPUS, and EBSCO. Studies published in the last ten years that met the inclusion criteria were included in this review. Seventeen studies exhibiting low to moderate risk of bias were included in this review, with eight on iris-fixated IOL (IFIOL), six on scleral-fixated IOL (SFIOL), and three on both IOLs. From the included studies, these data were extracted and compared: best-corrected visual acuity, endothelial cell density, postoperative complications, IOL stability, and intraocular pressure. IFIOL and SFIOL show comparable lens stability, offer good visual rehabilitation, and demonstrate equivalent safety profiles. There is no discerning superiority between IFIOL and SFIOL in treating pediatric ectopia lentis. The choice of which IOL to implant depends on the surgeon's preference.

Z-suture scleral fixation intraocular lenses: A refractive and safety report

PURPOSE

Scleral fixation of intraocular lenses constitutes a surgical option in cases where there is inadequate capsular support or zonular insufficiency. Knotless techniques, such as the z-suture technique, avoid suture-related complications, such as conjunctival erosion or exposure. The purpose of this study was to evaluate the visual outcomes and postoperative complications of patients who underwent scleral z-suture fixation of the Akreos AO® intraocular lenses.

METHODS

A retrospective, observational study was conducted, including 22 eyes of 20 patients who underwent Akreos AO® intraocular lenses using the z- suture scleral fixation technique.

RESULTS

The mean age of the patients was 55,64 ± 28,47 years old, and the mean follow-up time was 25,64 months. The most common indication for surgery was previous complicated cataract surgey. The mean postoperative spherical equivalent was +0,058D ± 0,79D, with values ranging from - 1,50D to +1,00D. Mean best-corrected visual acuity was 0,178 ± 0,15 logMAR. Intraocular pressure was 15,07 ± 2,56 mmHg on the day after surgery, and 16 ± 2,15 mmHg 1 month after. No suture-related complications were observed in any patient postoperatively. One patient had a slight inferonasal lens dislocation and another patient had a severe case of herpetic keratitis posoperatively.

DISCUSSION

The knotless z-suture technique appears to be a reliable and safe way to fix an intraocular lens in the sclera, regardless of the patient's age. Our results show good visual results and predictable refractive outcomes. Decades of follow-up may be necessary to assess the long-term risk of lens dislocation.

Application of the suture needle retrograde threading method in scleral fixation of intraocular lenses

BACKGROUND

Here we described a new threading technique for the universal fixation of any posterior chamber intraocular lens (IOL).

METHODS

Twenty-seven eyes of 27 patients whose surgery done by Surgeon A with the needle-guided method or the suture needle retrograde threading (SNRT) method for intrascleral IOL fixation were enrolled in the first group. Thirty-four eyes of 34 patients whose surgery done by Surgeon A, Surgeon B or Surgeon C with the SNRT method for intrascleral IOL fixation were grouped into three sub-groups by surgeon. Information regarding age, sex, best-available visual acuity (BCVA), intraocular pressure (IOP), past ophthalmological history, threading time (from puncturing to externalizing suture) and complications during and after the surgery were gathered.

RESULTS

The analysis showed that the threading time was less in the SNRT group than needle-guided group by Surgeon A. There was one eye with suture needle slipping from the guide needle when guiding out of the eye. The threading procedure was completed one time without suture ruptures or loop slippage in the SNRT group operated by Surgeon A. And using the SNRT method, Surgeon A, Surgeon B, and Surgeon C did not show any significant difference in threading time. No complications (e.g., vitreous hemorrhage, hyphemia, retinal detachment, suprachoroidal hemorrhage, or hypotony) were observed during surgery or postoperatively in all cases. No leakage occurred at the site of the puncture after the operation.

CONCLUSIONS

The described technique appears to be a safe, simple, easy-to-learn, and universal surgical method, which is suitable for various types of IOLs.

Intraocular lens dislocation: manifestation, ocular and systemic risk factors

PURPOSE

The aim of this study was to evaluate ocular and systemic risk factors for posterior chamber intraocular lens dislocation, as well as forms of manifestation.

METHODS

A retrospective case-control study were all patients presented in the period 2012-2016 having intraocular lens dislocation and being treated with implantation of an iris-fixated intraocular lens was conducted at the University Hospital Mainz. As controls, pseudophakic patients presenting for other reasons were included.

RESULTS

150 eyes of 150 patients (mean age 72.7 ± 12.4 years, range 24-93 years) with IOL dislocation and 150 eyes of 103 controls were included in this study. The average time between primary implantation and IOL luxation was 86 months (iQR: 39.25-127 months) for all dislocations. Previous pars plana vitrectomy (PPV) (crudeOR = 2.14 (95% CI 1.23, 3.72), p = 0.011) and PEX (crudeOR = 11.6 (4.79, 28.12), p < 0.001) was linked with a higher risk of IOL luxation. Luxation occurs also earlier in patients with previous PPV and PEX than in eyes with neither PEX nor previous PPV (82.2 vs. 127 months). Rhegmatogenous retinal detachment was the major pathology that required a previous PPV for eyes with an IOL dislocation (57%). The average time between PPV and IOL dislocation was 74.67 months (range 0-186 months).

CONCLUSION

Patients with a coexistence of both: PEX and a previous PPV had an elevated risk of IOL dislocation, and also had a shorter time interval between primary IOL implantation and IOL dislocation followed by eyes with PEX only and eyes with only a previous PPV.

Decompensated cornea with epithelial and stromal edema

A 66-year-old patient underwent surgery for congenital cataract in both eyes in her first year of life without implantation of an intraocular lens (IOL). In 1994, at the age of 39 years, both eyes received secondary Kelman multiflex-style angle-fixated anterior chamber IOLs (AC IOLs). The surgeries were followed by retinal detachments in both eyes, in the left eye in the same year and in the right eye 4 years later, which were successfully repaired. The patient presented with a decompensated cornea with epithelial and stromal edema in the left eye. The AC IOL axis was oriented from 5- to 8-o'clock position with the haptic contacting the cornea. The distal portion of the inferior-nasal haptic was deeply buried and entrapped in a broad iridocorneal synechia extending between 6- and 8-o'clock positions. The synechia also caused adjacent pupillary distortion and pigment leaf eversion (Figure 1JOURNAL/jcrs/04.03/02158034-202205000-00021/figure1/v/2022-04-22T173532Z/r/image-tiff). The AC IOL in the right eye was well positioned, and the cornea was clear with an endothelial cell count (ECC) of 2160 cells/mm2 and central corneal thickness (CCT) of 650 μm. No ECC was obtainable in the left eye, and CCT was 775 μm (Figure 2JOURNAL/jcrs/04.03/02158034-202205000-00021/figure2/v/2022-04-22T173532Z/r/image-tiff). Visual acuity was 0.8 corrected in the right eye and hand motion in the left eye. Both eyes were normotonic. On optical coherence tomography (OCT) imaging, a broad iridocorneal synechia was visible with a canal corresponding to the deeply buried haptic end of the AC IOL (Figure 3JOURNAL/jcrs/04.03/02158034-202205000-00021/figure3/v/2022-04-22T173532Z/r/image-tiff). Abundant condensed cortical material (Soemmerring's ring) was found behind the iris and above the ciliary body. What would be your surgical options to rehabilitate the patient's left eye considering corneal decompensation caused by haptic contact of an angle-fixated AC IOL and capture of 1 haptic within an iridocorneal synechia extending along 2 clock hours?

Technique of re-enclavation of post-traumatic disenclaved haptic of posterior iris claw lens in a vitrectomised eye

A 58-year-old woman presented to us with sudden onset diminution of vision for 10 days following trauma while using mobile phone. Patient had a history of posterior iris claw implantation 3 years ago. On examination, the patient was aphakic and intraocular lens (IOL) was seen enclaved on nasal side and disenclaved on temporal side on ultrasound biomicroscopy. Patient underwent surgery for re-enclavation of temporal haptic by lifting the IOL using 23-gauge pars plana trocar. Patient had a postoperative uncorrected visual acuity of 6/9 and best-corrected visual acuity of 6/6 with refraction. Re-enclavation of partially disenclaved posterior iris claw lens is a minimally invasive technique to restore visual acuity in such cases.

Iris-Claw Intraocular Lens: Anterior Chamber or Retropupillary Implantation? A Systematic Review and Meta-Analysis

Background and Objectives: Iris-claw intraocular lens (ICIOL) could be implanted in the anterior chamber (AC) or retropupillary (RP) in eyes lacking capsular and/or zonular support. Several studies have focused on comparing the efficacy and complications of these two techniques and we designed this research to review the published literatures. Materials and Methods: Peer-reviewed studies were collected through network databases (PubMed, Scopus, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov) and analyzed. The primary outcome was the standardized mean differences (SMDs) of pre- and post-operative corrected distant visual acuity (CDVA). The secondary outcome was the SMDs of pre- and post-operative intraocular pressure (IOP), endothelial cell counts (ECC), and the odds ratios (ORs) of post-operative IOP elevation and cystoid macular edema (CME). Comprehensive Meta-Analysis software was utilized to conduct statistical analysis. Results: Six studies (one randomized controlled trial and five retrospective case series) were relevant and included a total of 516 eyes (255 and 261 eyes in the AC ICIOL and RP ICIOL groups, respectively). The quantitative analysis showed no significant differences in CDVA (SMD: 0.164, 95% confidence interval (CI): -0.171 to 0.500), ECC (SMD: -0.011, 95% CI: -0.195 to 0.173), and IOP elevation events (OR: 0.797, 95% CI: 0.459 to 1.383). Lesser IOP reduction (SMD: 0.257, 95%CI: 0.023 to 0.490) and a relative increase in the incidence of CME (OR:2.315, 95% CI: 0.950 to 5.637) were observed in the AC ICIOL group compared with RP ICIOL group. Conclusions: Our meta-analysis indicated that AC and RP ICIOL seem to have equivalent visual outcomes. RP ICIOL may perform slightly better with more IOP reduction and lesser CME. More randomized controlled trials, which have higher patient participation and more outcomes are needed to confirm our conclusions.

Retropupillary Iris-Claw Intraocular Lenses: A Literature Review

Retropupillary iris-claw intraocular lenses (ICIOLs) have been increasingly chosen by surgeons nowadays as a primary or secondary procedure of IOL implantation in eyes with insufficient capsular or zonular support. They have gained popularity due to their simple fast technique, favourable functional outcomes, and safety. The transition in the ICIOL fixation from prepupillary to a more biologically appropriate retropupillary position and change in the optic design from biconvex to convex-concave have provided better visual outcomes and improved safety. A peer-reviewed literature search was conducted in Medline (PubMed), Embase, and Cochrane Library using the keywords "retropupillary iris claw" and "iris claw". The search yielded 310 articles that were screened. Forty-three articles on retropupillary ICIOLs were finally found to be relevant and reviewed in full-text versions. The functional outcomes following retropupillary implantation of ICIOLs have been acceptable in eyes with no ocular co-morbidities otherwise. However, the indications for surgery may affect the outcomes. The major postoperative complications directly associated with ICIOLs include pupil ovalization and redislocation. Nevertheless, the rate of disenclavation depends on the experience and skill of the surgeon. This review is based on a literature review, and it focuses on the preoperative evaluation, surgical technique, postoperative outcomes, and associated complications. Prospective randomized trials with a larger sample size and longer follow-up are needed for comparison with other techniques of IOL fixation and confirmation of long-term safety profile.