Three-Month Safety and Efficacy Outcomes for the Smaller-Incision New-Generation Implantable Miniature Telescope (SING IMT™)

SING IMT in pseudophakic eyes: Results of the first experiences

Purpose

To evaluate the feasibility and outcomes of implanting the Smaller-Incision New-Generation Implantable Miniature Telescope (SING IMT) in pseudophakic patients affected by late-stage dry AMD.

Subjects

Five pseudophakic patients' eyes with stable dry AMD were suitable for SING IMT implantation. Four eyes were excluded because of previous YAG laser capsulotomy. Patients underwent preoperative assessments, including visual acuity measurements and OCT scans.

Methods

Surgical procedures were performed under peribulbar anesthesia, with careful IOL removal and SING IMT implantation. Postoperative follow-up was conducted at regular intervals to monitor visual acuity, device positioning and complications.

Results

Postoperative outcomes demonstrated improvements in visual acuity for most patients with an average gain in CDVA (Corrected Distance Visual Acuity) and CNVA (Corrected Near Visual Acuity) of 16,8 ± 10,2 and 13,8 ± 7,4 ETDRS letters, respectively. Limited complications have been observed. In one case, we observed dislocation of the device into the vitreous chamber, which we managed through vitrectomy and scleral fixation of the SING IMT using GoreTex suture.

Conclusions

Despite being traditionally contraindicated for pseudophakic patients, SING IMT implantation in selected cases yielded favorable outcomes, indicating potential benefits for this population. Further research with larger sample sizes and longer follow-up periods is warranted to refine patient selection criteria and optimize surgical techniques.

Summary of the Therapeutic Options for Patients with Dry and Neovascular AMD

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness worldwide and a severe medical and social problem. The steadily increasing number of patients is related to the aging of the population. So far, many factors affecting the development of AMD have been identified, which can be divided into non-modifiable, including genetic factors, age, and sex, and modifiable or environmental factors, such as smoking, poor diet, and hypertension. Early stages of age-related macular degeneration are characterized by fundus drusen and abnormalities in the retinal pigment epithelium. In late stages, geographic atrophy and choroidal neovascularization (CNV) are observed. The treatment of AMD, especially its advanced forms, is very challenging. Intensive research has made it possible to treat advanced stages of the dry form of AMD with pegcetacoplan and avacincaptad pegol, new drugs approved for use in the US. Pegcetacoplan targets the C3 and avacincaptad pegol targets the C5, the pivotal proteins of the complement cascade. The drugs are administered by intravitreal injection. The gold standard for neovascular AMD (nAMD) consists of intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) drugs such as bevacizumab, ranibizumab, aflibercept, brolucizumab, and faricimab. Treatment can be administered according to the fixed, pro-re-nata, and treat-and-extend regimens. The latter seems to have the best effect on improving visual acuity (VA) and the maximum therapeutic benefit. The search continues for the best ways to deliver intravitreal drugs. Current methods include sustained-release implants and hydrogel platforms for drug release, while the most promising future pathways for treating dry and nAMD are stem cell and gene therapy.

Analysis of Choriocapillaris Reperfusion Topography following Faricimab Treatment for Neovascular Age-Related Macular Degeneration in Non-Treatment-Naïve Patients

To assess changes in choriocapillaris (CC) vascular density surrounding macular neovascularization (MNV) in age-related macular degeneration (AMD) when transitioning from various anti-VEGF treatments to faricimab, using optical coherence tomography angiography (OCTA). 25 eyes of 22 individuals who underwent intravitreal faricimab injections for neovascular AMD with type 1 MNV were included. OCTA images were obtained prior to (T0), after one (T1), and after three faricimab injections (T2); Noteworthy changes occurred in the first ring at T2 in comparison to T0. The percentage of CC flow deficit (FD%), FD average area (FDa), and FD number (FDn) in 5 rings (R1-R5) surrounding the dark halo around the MNV were calculated. A reduction in FD% at T2 compared to T0 (50.5 ± 10.2% at T0, 46.4 ± 10.6% at T2; p = 0.020) was seen, indicating CC reperfusion. Additionally, we observed a reduction in the average FDa (140.2 ± 172.1% at T0, 93.7 ± 101.8% at T2; p = 0.029). Our study highlights an FD% after three consecutive faricimab injections. The most pronounced effect was observed in the first ring, directly adjacent to the dark halo, suggesting a partial CC reperfusion surrounding the MNV, potentially indicating disease regression.

Enhancing the Functional Performance of Patients with Late-Stage Age-Related Macular Degeneration Implanted with a Miniature Telescope using Rehabilitation Training

INTRODUCTION

In this work, our aim is to report the functional outcomes of cataract surgery with smaller-incision new-generation miniature telescope (SING IMT) implantation followed by rehabilitation training in patients with central visual loss due to late-stage age-related macular degeneration (AMD).

METHODS

This retrospective study included patients who were monocularly implanted with SING IMT and then followed a rehabilitation program based on 6 biweekly sessions focused on visual abilities, reading, writing, visual motor integration and mobility. A total of 11 participants were included in this study. Reading acuity (RA), reading speed (RS), and fixation stability (FS) were assessed biweekly at 6-, 8-, 10-, 12-, 14-, and 16-week follow-up visits after SING IMT implantation and at a final assessment at 24 weeks. Best-corrected distance visual acuity (BCDVA) was also measured at baseline and at the same postoperative timepoints.

RESULTS

Mean baseline BCDVA was 12.5 ± 8.6 letter score. Both RA and RS were found to be significantly improved from the first rehabilitation session (6 weeks after surgery) to the last session (24 weeks after surgery). At the end of the rehabilitation program, mean RA was 0.45 ± 0.19 LogMAR and mean RS was 30.9 ± 17.6 words per minute. Moreover, all patients achieved a FS of 15 s or more after the last rehabilitation session. Most patients (55%) achieved an improvement of 15 letters in BCDVA at the end of the study.

CONCLUSIONS

This study suggests that rehabilitation training can improve visual functions of patients with late-stage AMD implanted with SING IMT in real-world tasks such as reading skills.

Intraoperative Iridectomy in Femto-Laser Assisted Smaller-Incision New Generation Implantable Miniature Telescope

BACKGROUND

In this study, we aimed to report the short-term (6 months) effects on visual functionality and safety of femto-laser assisted smaller-incision new-generation implantable miniature telescope (SING-IMT™) implanting, particularly related to postsurgical intraocular pressure increase, in patients suffering from end-stage age-related macular degeneration (AMD) and cataract. This device, designed for monocular use, aims to minimise the impact of the central scotoma by projecting the images onto a larger area of the photoreceptors surrounding the macula.

METHODS

In this prospective multicentric observational case series study, 6 eyes of 6 patients who underwent SING-IMT™ implantations were enrolled. At baseline and 6 months follow-up, best corrected distance visual acuity (BCDV) and best corrected near visual acuity (BCNVA), intraocular pressure (IOP), anterior chamber depth, endothelial cells count were assessed. In addition, IOP was also measured at 7, 15, 30, 45 days, and at 3 months follow-up. Finally, the incidence of complications was evaluated.

RESULTS

At final follow-up, in the study eyes, mean BCDVA improved by +10.0 letters (6.25; 13.8) letters and mean BCNVA improved by -0.30 logMAR (-0.55; -0.20). At postoperative month 6, we reported a mean IOP decrease of 4.50 mmHg (-5.75; -0.25). Interestingly, 83.3% of patients had an increased IOP value in at least one of the first two postoperative follow-ups (7 days and 15 days). In patients in whom intraoperative mechanical iridotomy was not performed, it was necessary to perform a postoperative YAG laser iridotomy to improve IOP management. Compared to the baseline, ECD loss at 6 months follow-up was 12.6%.

CONCLUSIONS

The SING IMT™ device was found to be effective in the distance and near vision improvement, without serious postoperative complications. We recommend intraoperative mechanical iridectomy in order to easily manage post-operative IOP and to avoid sudden IOP rise with its possible consequences. These good results can be a hope to partially improve the quality of life of patients suffering from severe end stage macular atrophy.

Capsule Dynamics, Implantation, and Explantation of the Smaller Incision, New-Generation Implantable Miniature Telescope: a Miyake-Apple Study

PURPOSE

The smaller incision, new-generation implantable miniature telescope is a novel implant to optimize vision in retinal patients with central vision loss. Using Miyake-Apple techniques we visualized the device implantation, repositioning, and explantation, while noting capsular bag dynamics.

METHODS

Using the Miyake-Apple technique, we assessed capsular bag deformation after successful implantation of the device in human autopsy eyes. We assessed rescue strategies for converting a sulcus implantation to a capsular implantation and explantation strategies. We noted the occurrence of posterior capsule striae, zonular stress, and the haptics' arc of contact with the capsular bag after implantation.

RESULTS

Acceptable zonular stress was observed during the successful implantation of the SING IMT. When it was implanted in the sulcus, one could reposition the haptics into the bag with two spatulas using counter-pressure in an effective strategy despite inducing tolerable, medium zonular stress. A similar technique, in reverse, allows safe explantation without damaging the rhexis or the bag, while inducing similar medium, tolerable zonular stress. In all eyes we examined, the implant considerably stretches the bag, inducing a capsular bag deformation and posterior capsule striae.

CONCLUSION

The SING IMT can be safely implanted without significant zonular stress. In sulcus implantation and explantation, repositioning of the haptic is achievable without perturbing zonular stress using the presented approaches. It stretches average-sized capsular bags to support its weight. This is achieved by an increased arc of contact of the haptics with the capsular equator.

Optical-Quality Assessment of a Miniaturized Intraocular Telescope

Age-related macular degeneration (AMD) causes severe vision impairments, including blindness. An option to improve vision in AMD patients is through intraocular lenses and optics. Among others, implantable miniaturized telescopes, which direct light to healthy lateral regions of the retina, can be highly effective in improving vision in AMD patients. Yet, the quality of the restored vision might be sensitive to the optical transmission and aberrations of the telescope. To shed light on these points, we studied the in vitro optical performance of an implantable miniaturized telescope, namely, the SING IMT™ (Samsara Vision Ltd., Far Hills, NJ, USA) designed to improve vision in patients affected by late-stage AMD. Specifically, we measured the optical transmission in the spectral range 350-750 nm of the implantable telescope with a fiber-optic spectrometer. Wavefront aberrations were studied by measuring the wavefront of a laser beam after passing through the telescope and expanding the measured wavefront into a Zernike polynomial basis. Wavefront concavity indicated that the SING IMT™ behaves as a diverging lens with a focal length of -111 mm. The device exhibited even optical transmission in the whole visible spectrum and effective curvature suitable for retinal images magnification with negligible geometrical aberrations. Optical spectrometry and in vitro wavefront analysis provide evidence supporting the feasibility of miniaturized telescopes as high-quality optical elements and a favorable option for AMD visual impairment treatments.