AIM

To assess the cost-effectiveness of autologous retinal pigment epithelium and choroid translocation (PATCH) in neovascular age-related macular degeneration (AMD).

METHODS

Visual acuity and complication rates of published patient series were used to determine the incremental utility of treatment for the patient. The utility data applied assume that the better eye was affected. Comparator was a meta-analysis of recent control groups, in which patients received best supportive care. To assess cost-effectiveness, costs per quality adjusted life years (QALYs) and costs of avoiding low vision (“legal blindness”, i.e. ≤20/200) were calculated. Costs were based on a German sick fund perspective and in a scenario on US costs. Robustness of the model was investigated by univariate and probabilistic multivariate sensitivity analysis (PSA).

RESULTS

Cost-utility analysis showed surgery to be the dominant (“cost-saving”) strategy for Germany and for the US in both, cost-effectiveness and cost-utility analysis (costs per QALY). In the sensitivity analysis the intervention remained dominant or cost-effective in all scenarios investigated. Clinical outcomes and duration of modeling were the most influential factors in the sensitivity analyses.

CONCLUSION

Therapy of neovascular AMD by PATCH is a cost-effective treatment option for selected patients, who are not well suitable for other current treatment options.

Background

Translocation of a free autologous graft consisting of retinal pigment epithelium (RPE), Bruch's membrane, choriocapillaris and choroid in patients with exudative age‐related macular degeneration is currently being evaluated in clinical practice. Angiographic studies in these patients suggest that their grafts become revascularised.

Aim

To investigate the histological evidence of revascularisation of the graft in a porcine model.

Methods

In 11 pigs (11 eyes), an RPE–choroid graft was translocated from the mid‐periphery to an intact or an intentionally damaged RPE and Bruch's membrane at the recipient site. The eyes were enucleated 1 week or 3 months after surgery. Tissue sections were evaluated using immunohistochemistry.

Results

Bridging vessels between recipient layer and graft were identified from 1 week to 3 months after surgery. This reconnection occurred regardless of whether the Bruch's membrane of the recipient site was left intact or intentionally damaged at the time of transplantation. The vasculature of the graft appeared open and perfused. Vessels with transcapillary pillars and conglomerates of small new vessels were present in the graft.

Conclusions

This study showed histological evidence for revascularisation by angiogenesis of a free autologous RPE–choroid graft.

Aim

To investigate whether the emulsification of conventional silicone oils can be reduced by adding small amounts of silicone molecules of a very long chain length.

Methods

Siluron 1000, Siluron 2000, Siluron 5000, Acri.Sil-Ol 5000, Oxane 5700, Densiron 68 LV, Densiron 68 and Densiron 68 HV (0.5 ml) were each tested along with either plasma or serum (0.5 ml) in a glass cuvette. Emulsification was induced by sonication and documented by photography. The total area of emulsified oil was assessed using the ImageJ software.

Results

The addition of small amounts of very-long-chain silicone molecules significantly reduced the emulsification for 1000 cSt silicone oil (Siluron 2000) and for 1000 cSt silicone oil with an admixture of F6H8 (Densiron 68 HV).

Conclusion

New low-viscosity silicone oils show a reduced emulsification similar to that of 5000 cSt oils. In future, it may be possible to avoid using 5000 cSt oils. The findings may foster silicone oil surgery in general, and in particular the application of small-incision techniques.

Purpose

To evaluate the long-term outcome of autologous graft of retinal pigment epithelium (RPE) in patients with geographic atrophy.

Methods

Ten patients with progressive geographic atrophy underwent translocation of an autologous graft of RPE, Bruch membrane and choroid. The visual acuity (VA), reading performance, microperimetry, optical coherence tomography (OCT), fundus autofluorescence, fluorescein angiography and indocyanine green angiography were assessed.

Results

No recurrence of RPE atrophy was seen. All but one transplant were revascularised. Vascularisation persisted throughout the 3 years' follow-up. Spectral-domain OCT in some cases showed intact photoreceptors or intact outer nuclear and outer plexiform layer overlying the graft. In three cases, the grafts were positioned eccentrically; these patients did not benefit from surgery. The mean VA decreased from 20/80 (range: 20/800 to 20/40) at baseline to 20/200 (range: perception of hand movements to 20/32) at last follow-up. In two patients, VA were stable from 20/50 to 20/32 and 20/40 at the last follow-up, respectively. Postoperative complications included retinal detachment due to proliferative vitreoretinopathy, macular pucker, iritis, branch retinal vein occlusion and secondary ocular hypertension.

Conclusions

Some patients benefit for at least 3 years from a functioning RPE-choroid graft. Functional outcome in most patients, however, was limited due to complications and unfavourable patient selection.

Aim

To study tissue remodelling and wound healing after retinal pigment epithelium (RPE) tears due to age-related macular degeneration.

Methods

Retrospective longitudinal study of 36 eyes (33 patients) with RPE tears. Imaging was performed using fundus autofluorescence (FAF) (λ=488 nm) and spectral-domain optical coherence tomography (SD-OCT). Presence of intraretinal hyper-reflective dots in SD-OCT, which correlated with hyperfluorescent dots in FAF, indicating RPE migration was studied. Morphology of subretinal mass and RPE layer integrity in the RPE denuded area over time were examined.

Results

7 of 36 eyes (19.4%) showed patchy or hazy hyperfluorescent areas in FAF, and the majority of eyes (83.3%) showed hyper-reflective dots, which possibly represent intraretinal RPE migration and hard exudates. Homogenous subretinal mass was encountered in about half of all cases. In one case (2.8%), the RPE layer proliferated and covered the defect.

Conclusions

SD-OCT and FAF showed a considerable amount of RPE proliferation, migration and repopulation. Intraretinal RPE migration did not form a functional RPE layer. A small defect might be repaired by cell proliferation. But this RPE proliferation is not sufficient to cover large defects.

Aims

To study the variability of central retinal thickness (CRT), its concordance to the fellow eye, and the implications for designing future clinical trials using spectral-domain optical coherence tomography (SD-OCT).

Methods

Cross-sectional retrospective analysis of European Genetic Database. 632 eyes of 316 subjects over 60 years of age without macular pathology were examined using SD-OCT.

Results

Mean CRT was 280.22 µm and 281.02 µm for the right and left eyes, respectively. There was a strong concordance for all measured values between right and left eyes. Men had significantly thicker CRT than women. Variation up to 23 µm difference between both eyes was seen. To detect a change of at least 30 µm in CRT, a sample size of 90 or 176 per group is needed for a single-arm or double-arm study, respectively (α=0.05, power=0.80, no loss to follow up, assuming SD in future studies=100 µm).

Conclusions

Clinical trials using CRT as an endpoint are feasible in terms of sample size needed.