Iris-fixated phakic intraocular lens implantation for correction of high myopia in microspherophakia

Visual outcomes and safety profile of intraocular lens implantation versus aphakia in children with microspherophakia with no subluxation

Objective

To study the visual, refractive and surgical outcomes of intraocular lens (IOL) implantation versus aphakia in children with microspherophakia.

Design

Retrospective, comparative, non-randomised interventional study.

Methods

All consecutive children with microspherophakia who satisfied the inclusion criteria were included. The eyes that underwent in-the-bag IOL implantation and those that were left aphakic were included in groups A and B, respectively. The postoperative visual outcomes, IOL stability and complications during the follow-up period were studied.

Results

22 eyes (13 patients, male 76%), of which 12 eyes were in group A and 10 eyes in group B. The mean±SE of age at surgery was 9.4±1.4 and 7.3±0.9 years in group A and group B, respectively (p value 0.18). The mean follow-up of group A was 0.9±0.4 years (median 0.5 years; Q1 0.04, Q3 2.16) and group B was 1.3±0.9 years (median 0.147 years; Q1 0.08, Q3 0.39) (p value 0.76). All the baseline biometric variables including best-corrected visual acuity (BCVA) were comparable in each group. The final BCVA in logMAR adjusted for follow-up was comparable in both group A (0.29±0.06) and group B (0.52±0.09) (p value 0.06). Mean predictive error of IOL power in microspherophakia was 0.17±0.43.

The most common complication in group A was visual axis opacification of two eyes (16.7%, 95% CI 2.9% to 49.1%), of which one eye (8.3%, 95% CI 0.4% to 40.2%) needed membranectomy. Vitreous in anterior chamber was the most common complication in group B, seen in two eyes (20%, 95% CI 3.5% to 55.8%), of which one eye (10%, 95% CI 0.5% to 45.9%) underwent YAG laser vitreolysis. The survival analysis (p value 0.18) was comparable in each group.

Conclusion

In-the-bag IOL is an option, which can be considered in selected cases of microspherophakia in developing nations where regular follow-up and economic constraints are a major concern.

Factors Related to Visual Outcomes after Lens Surgery in Isolated Microspherophakia

Purpose. To evaluate the main factors influencing visual performance after lens subluxation surgery in subjects with isolated MSP. Design. Retrospective study. Methods. In this study, 38 eyes of subjects with isolated MSP (microspherophakia) were included and divided into two groups based on preoperative IOP (intraocular pressure), IOP <21 mmHg, or IOP ≧21 mmHg. Phacoemulsification and scleral-fixated modified capsular tension ring implantation were performed with or without goniosynechialysis according to the IOP. Some ocular biometric parameters, such as corneal curvature, corneal pachymetry, endothelial cell count (ECC), anterior chamber depth (ACD), and axial length, were evaluated. The best-corrected visual acuity (BCVA) and IOP of these subjects were measured before the surgery and during <1 month and 3- to 6-month postoperative follow-ups. Results. Compared with the high IOP group, the normal IOP group was significantly younger and had better preoperative BCVA, a higher ECC, deeper ACD, a lower postoperative IOP, and flatter total corneal refractive power K1. The multivariable analysis revealed that preoperative ACD (b = −0.113, t = −2.070, $P=0.047$ ) and preoperative BCVA (b = 0.153, t = 2.562, $P=0.015$ ) were significantly associated with postoperative BCVA at 3–6 months. A preoperative ACD of 1.86 mm was found to be the optimal cut-off point for 3- to 6-month postoperative BCVA of ≧20/63 (≤0.52 logMAR). Conclusions. In addition to the effect of normal IOP, better preoperative BCVA and deeper ACD also correlated with better visual outcomes after lens surgery. Preoperative ACD served as a warning for isolated MSP subjects, especially for the risk of irreversible loss of postoperative vision. This trial is registered with “ChiCTR2000039132.”

Diagnosis and treatment of microspherophakia

As a rare congenital disease, microspherophakia (MSP) is characterized by small and spherically shaped crystalline lenses. The common complications of MSP include secondary glaucoma and crystalline lens dislocation or subluxation. Patients with MSP often show high lenticular myopia. The special morphological characteristics and complex complications bring challenges to the treatment of patients with MSP. Although there are some studies on MSP, most are case reports. In this article, the morphological characteristics, complications, genetic diagnosis, and treatment of MSP were systematically reviewed, providing valuable insight into the clinical diagnosis and treatment of this disease.

Scleral-fixated intraocular lens implantation in microspherophakia

Background:

In microspherophakia, abnormal laxity of the lenticular zonules leads to development of a spherical lens and possible subluxation. We evaluated long-term results of lens removal with scleral-fixated intraocular lens (SFIOL) implantation in microspherophakia.

Materials and Methods:

Case series. SF IOLs were implanted in four consecutive patients with bilateral microspherophakia (eight eyes [three with pupillary block and secondary glaucoma who underwent immediate surgery and five with only subluxation who underwent elective surgery]). Post-operative best-corrected visual acuity (BCVA), intraocular pressure (IOP) and lens position were evaluated periodically from day 1 to 18 months.

Results:

All patients were females (mean age 28 ± 7.03 years). In group 1 eyes (three eyes that presented with pupillary block), the mean BCVA improved from 0.008 decimals (preoperative) to 0.50 decimals (final post-operative visit); in group 2 eyes (the other five eyes), the mean BCVA improved from 0.12 ± 0.21 decimals to 0.73 ± 0.14 decimals. The preoperative mean IOP (54.53 ± 7.33 mmHg) in group 1 eyes was significantly (P = 0.03) higher than that (16 ± 4.30 mm Hg) in group 2 eyes. At final post-operative visit, the mean IOP (11.67 ± 2.88 mmHg) in group 1 eyes was not significantly different from that in group 2 eyes (13.0 ± 3.08 mmHg). All SFIOLs were well- centred at the final visit. None of the patients encountered any peroperative or postoperative complications.

Conclusions:

SFIOLs may be an option for surgical management of microspherophakia.

Incidence rate and occurrence of visually significant cataract formation and corneal decompensation after implantation of Verisyse/Artisan phakic intraocular lens

Purpose

To evaluate the incidence rate and indications for explantation of Verisyse phakic intraocular lenses (pIOLs) over a 13.6 year period.

Subjects and methods

Case series describing six cases of explantation of Verisyse pIOLs, out of 213 eyes with Verisyse pIOLs, implanted over a 13.6 year period by one surgeon at one institution, with mean follow-up of 5.6 years per eye.

Results

Four pIOLs were removed to facilitate extraction of a visually significant cataract, one was removed due to both cataract formation and development of corneal decompensation, and another was removed due to development of localized peripheral corneal decompensation. The incidence rate of pIOL removal was five per 1,000 patient-years with pIOL. Mean time from insertion of pIOL to cataract removal was 9.3 years (range 4.0–12.6 years). Mean time from insertion of pIOL to development of corneal decompensation was 10 years (range 6.9–13 years). There was no increase in the rate of cataract extraction in the pIOL population compared to the general population.

Conclusion

Cataracts may develop in patients with pIOLs, necessitating removal of the pIOL. Corneal decompensation is a serious complication that appears to be directly related to pIOLs. Corneal decompensation can occur up to 13 years following implantation of pIOLs, and long-term follow-up is important to monitor for this complication.

Three-year follow-up of secondary anterior iris fixation of an aphakic intraocular lens to correct aphakia

PURPOSE

To evaluate the efficacy, predictability, stability, safety, and complications of secondary anterior iris fixation of the Artisan iris-fixated intraocular lens (IOL) to correct aphakia in eyes without sufficient capsule support.

SETTING

Department of Ophthalmology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China.

DESIGN

Cohort study.

METHODS

Eyes having implantation of aphakic iris-fixated IOLs for aphakia correction were followed for 3 years.

RESULTS

The study evaluated 72 eyes (72 patients). After 3 years, the uncorrected distance visual acuity improved in all eyes (P<.05); 53 eyes (73.6%) reached 20/40 or better. Two eyes had a postoperative corrected distance visual acuity (CDVA) worse than the preoperative CDVA due to postoperative ischemic optic neuropathy and retinal detachment, respectively. The mean spherical equivalent (SE) decreased from 11.65 diopters (D) ± 1.21 (SD) to -0.58 ± 0.56 D (P<.05); the SE at the last follow-up was within ±1.00 D of the target refraction in 63 eyes (87.5%). The mean endothelial cell loss 3 years postoperatively was 9.78%. There was no significant postoperative intraocular pressure increase throughout the follow-up. Twelve patients (16.7%) reported glare and halos during night driving. Iris pigment precipitates on the IOLs occurred in 4 eyes (5.6%) 3 years postoperatively. No other serious complications occurred.

CONCLUSIONS

Three-year results indicate that secondary implantation of aphakic IOLs is effective, predictable, and safe for the correction of aphakia in eyes without capsule support. However, longer follow-up with a larger cohort is necessary to confirm these conclusions.