Two-year results of macular translocation with scleral infolding in myopic choroidal neovascularisation

Long-term results after limited macular translocation surgery for wet age-related macular degeneration

Purpose

To evaluate the long-term results of limited macular translocation (LMT) surgery with radial chorioscleral outfolding in patients with wet age-related macular degeneration (AMD) and subfoveal choroidal neovascularization (CNV). In addition, to identify the factors associated with the final best-corrected visual acuity (BCVA).

Methods

The medical records of 20 eyes of 20 consecutive patients (65.2±9.8 years) who had undergone LMT for the treatment of wet AMD and were followed for at least 5 years, were reviewed. The surgical outcomes including the BCVA, degree of foveal displacement, and complications were recorded.

Results

The mean foveal displacement was 1332 ± 393 μm after the LMT. The CNV was removed in 16 eyes and photocoagulated in 4 eyes. The mean preoperative VA was 0.83 ± 0.33 logMAR units which significantly improved to 0.59 ± 0.37 logMAR units at 1 year after the surgery (P = 0.015). This BCVA was maintained at 0.59 ± 0.41 logMAR units on the final examination. The final BCVA was significantly correlated with that at 1 year after the surgery (r = 0.83, P<0.001). Multiple linear regression analysis showed that the final BCVA was significantly correlated with the BCVA at 1 year after the surgery (P<0.001), a recurrence of a CNV (P = 0.001), and the age (P = 0.022).

Conclusions

LMT improves the BCVA significantly at 1 year, and the improved BCVA lasted for at least 5 years. These results indicate that the impaired function of the sensory retina at the fovea can recover on the new RPE after the displacement for at least 5 years. The ability to maintain good retinal function on the new RPE for a long period is important for future treatments of CNVs such as the transplantation of RPE cells and stem cells.

Therapeutic effect of intravitreal injections of ranibizumab for the treatment of macular choroidal neovascularization caused by pathological myopia

The aim of the present study was to evaluate the clinical efficacy and safety of intravitreal ranibizumab injections for the treatment of macular choroidal neovascularization (CNV) caused by pathological myopia. Between one and four intravitreal injections of ranibizumab were administered to 61 eyes from 61 patients who were diagnosed with macular CNV caused by pathological myopia. Following injection, the best-corrected visual acuity (BCVA), central macular thickness (CMT) and fundus fluorescein angiography (FFA) findings were evaluated monthly for a period of 6 months. Among the 61 eyes, 10 eyes received one injection, 44 received two injections, six received three injections and one received four injections (average, 1.97 injections). The BCVA was 0.02±0.01 prior to treatment and 0.30±0.03 subsequent to treatment, and this difference was statistically significant (P<0.01). The CMT was reduced by an average of 45.1 µm. Regarding the FFA results, 56 eyes had no CNV fluorescence leakage and five eyes had CNV fluorescence leakage following treatment; however, the intensity of CNV fluorescence leakage in the five eyes following treatment was lower than that prior to treatment. As a treatment for pathological myopia-induced macular CNV, intravitreal injections of ranibizumab may improve eyesight as well as the macular retinal tissue structure; thus, this is a safe and effective treatment method.

Choroidal neovascularization secondary to pathological myopia

Myopic choroidal neovascularization (mCNV), one of the complications of pathological myopia, is also one of the leading causes of visual impairment worldwide. The socioeconomic impact of mCNV in Asian countries is particularly significant due to the rising incidence of pathological myopia. There have been major advances in the treatment of mCNV in the past few years. Previous treatment modalities, such as thermal laser photocoagulation and photodynamic therapy, aimed to prevent vision loss; however, newer modalities such as intravitreal anti-vascular endothelial growth factor (VEGF) agents have been shown to successfully restore vision in many patients. Challenges remain as long term safety and efficacy of anti-VEGF agents are unknown. This article aims to provide a review of the literature of the epidemiology, progression, clinical course and treatment modalities as well as areas of future developments related to myopic CNV.

Major challenges in vitreoretinal surgery

Since the first vitrectomy surgery was used for treatment of vitreoretinal diseases, surgical techniques and instrumentation have been rapidly improved in the past decades. However, there are complicated vitreoretinal diseases that cannot be successfully treated, even with state-of-the-art surgeries. The outcomes of some complicated cases are still poor due to different reasons and debates still remain in some areas regarding what are the best treatments. There is still a lack of full understanding on many complicated vitreoretinal diseases, such as the molecular basis of proliferative vitreoretinopathy (PVR), the role of scleral buckling (SB) in the management of rhegmatogenous retinal detachment (RRD), the optimal surgical consideration for pediatric RD, and the possibility of surgical management for various retinal degenerations and congenital retinal anomalies. This review discusses the current understandings of some complicated vitreoretinal diseases.

Choroidal neovascularization in pathological myopia

Myopic choroidal neovascularization (CNV) is one of the leading causes of visual impairment worldwide. The clinical and socioeconomic impact of myopic CNV in Asian countries is particularly significant due to rising trend in the prevalence and severity of pathological myopia. The exact pathogenesis of myopic CNV remains unclear and there is paucity of information with respect to incidence and risk factors for myopic CNV from prospective studies. Furthermore, there are no recognized measures that may prevent or delay the development of CNV in eyes with pathological myopia. Advances have been made in the diagnosis and characterization of myopic CNV over the years. Until recently, treatment modalities for myopic CNV were limited to thermal laser photocoagulation and photodynamic therapy with verteporfin, both these modalities primarily aim at prevention of further visual loss. In the last 5 years, inhibitors of vascular endothelial growth factor (VEGF) have been used successfully and may improve vision to some extent. Nevertheless, the long-term safety and efficacy of anti-VEGF agents remains unknown. Furthermore, the risk of developing chorioretinal atrophy remains the key factor in determining the final visual outcome. This review article summarizes the current literature on myopic CNV, highlighting new evolving diagnostic and treatment modalities, prognostic factors influencing visual outcome, and areas of future research.

Intravitreal ranibizumab (Lucentis) for the treatment of myopic choroidal neovascularization

BACKGROUND

Macular choroidal neovascularization (CNV) is one of the most vision-threatening complications of myopia, which can lead to severe vision loss. The purpose of this study was to evaluate the safety and efficacy of intravitreal ranibizumab in the treatment of myopic CNV.

METHODS

We conducted a prospective, consecutive, interventional study of patients with subfoveal or juxtafoveal CNV secondary to pathologic myopia (PM) treated with intravitreal injection of ranibizumab in the Jules Gonin University Eye Hospital from June 2006 to February 2008. Best-corrected visual acuity (BCVA), optical coherence tomography (OCT), and fluorescein angiography (FA) were performed at baseline and monthly for all patients. Indications for retreatment were loss in BCVA associated either with persistent leakage from CNV shown on FA, and/or evidence of CNV activity on OCT.

RESULTS

The study included 14 eyes of 14 patients. The mean spherical equivalent refractive error was -12.5 (range, -8.0 D to -16.0 D). Mean time of follow-up was 8.4 months (range from 3 to 16 months, SD: 3). The mean number of intravitreal injections administered for each patient was 2.36 (SD 1.5). The mean initial visual acuity (VA) was 0.19 decimal equivalent (log-MAR: 0.71, SD: 0.3). A statistically significant improvement to a mean VA of 0.48 decimal equivalent (log-MAR:0.32, SD: 0.25) was demonstrated at the final follow-up. VA improved by a mean of 3.86 (SD 2.74) lines. Nine patients (64%) demonstrated a gain of 3 or more lines. Mean central macular thickness (CMT) measured with OCT was 304 microm (SD: 39) at the baseline, and was reduced significantly at the final follow-up to 153 microm (SD: 23). Average CMT reduction was 170 microm (SD: 57). No injection complications or drug-related side effects were noted during the follow-up period.

CONCLUSIONS

In this small series of eyes with limited follow-up, intravitreal ranibizumab was a safe and effective treatment for CNV secondary to PM, resulting in functional and anatomic improvements.

Photodynamic therapy vs limited macular translocation in the management of subfoveal choroidal neovascularization in pathologic myopia: a two-year study

PURPOSE

To compare the results of limited macular translocation and photodynamic therapy (PDT) in subfoveal choroidal neovascularization (CNV) attributable to pathologic myopia with a 24-month follow-up.

DESIGN

Retrospective analysis of nonrandomized interventional clinical study.

METHODS

Retrospective review of 66 consecutive patients: 34 myopic eyes with subfoveal neovascularization treated by PDT and 32 operated on with the translocation technique. Translocation was considered principally when the lesion size was adequate (nasal inferior margin of the membrane less than half a disk diameter away from the center of the fovea) with duration of symptoms of less than four months. Main outcome measure was the postoperative change in visual acuity.

RESULTS

In the translocation group, mean gain in visual acuity was greater than in the PDT group (+2.8 lines and -1.8 line, respectively, P = .001). In the translocation group, 55% of eyes gained 3 lines or more at two years compared with 10% in the PDT group. Sixty percent of eyes in the translocation group vs 40% in the PDT group had an improvement of at least five letters. Mean foveal displacement after translocation was 906 mum; postoperative complications included retinal detachment (three eyes), macular fold (one eye), and transient diplopia (four eyes). In young patients, the postoperative gain was better in both groups. In the translocation group, mean survival time for choroidal neovascularization recurrence was 40 months for patients younger than 40 years and 20 months for older patients.

CONCLUSIONS

Translocation showed better results than PDT at two years. Further studies are required to confirm these findings.

Choroidal neovascularisation in pathological myopia: an update in management

Choroidal neovascularisation (CNV) secondary to pathological myopia is an important cause of significant visual impairment in young and middle aged adults globally and is particularly prevalent in Asian populations. In the past few years, there have been rapid advancements in the different treatments for myopic CNV. The purpose of this perspective is to give an overview of the natural history of myopic CNV and the various treatment options including laser photocoagulation, photodynamic therapy, sub-macular surgery, and macular translocation surgery. Future directions in the management of myopic CNV are also discussed.

Effect of experimental scleral shortening on axial length of the rabbit eye

PURPOSE

To evaluate the change of axial length (AL), intraocular pressure (IOP), and corneal astigmatism after scleral shortening with scleral invagination in the rabbit eye.

METHODS

The authors performed scleral shortening (3 mm) with scleral invagination in two groups of 6 eyes each: 180 degrees (group 1) and 360 degrees (group 2).

RESULTS

Average AL shortening was more prominent in group 2 (0.5 +/- 0.17 mm) than in group 1 (0.37 +/- 0.29 mm), but the difference was not statistically significant. IOP increased immediately after the procedure and was maintained at a high level through 2 months postoperatively. Induced corneal astigmatism was more prominent in group 1 than in group 2. The difference was statistically significant in group 1 (p<0.05) but not in group 2.

CONCLUSIONS

In the scleral shortening with scleral invagination procedure, a large amount of scleral invagination resulted in more shortening of axial length, but there was more corneal astigmatism in 180-degree invagination of the sclera than in 360-degree. Further research is required to determine the effect of the extent of scleral invagination on the change of these values.