Outcome of Transplantation of Autologous Retinal Pigment Epithelium in Age-Related Macular Degeneration: A Prospective Trial

Chan

Survey of Ophthalmology

et al. 2007

Abstract. Multifocal electroretinography (mfERG) is an investigation that can simultaneously measure multiple electroretinographic responses at different retinal locations by cross-correlation techniques. mfERG therefore allows topographic mapping of retinal function in the central 40--50 of the retina. The strength of mfERG lies in its ability to provide objective assessment of the central retinal function at different retinal areas within a short duration of time. Since the introduction of mfERG in 1992, mfERG has been applied in a large variety of clinical settings. This article reviews the clinical applications of mfERG based on the currently available evidence. mfERG has been found to be useful in the assessment of localized retinal dysfunction caused by various acquired or hereditary retinal disorders. The use of mfERG also enabled clinicians to objectively monitor the treatment outcomes as the changes in visual functions might not be reflected by subjective methods of assessment. By changing the stimulus, recording, and analysis parameters, investigation of specific retinal electrophysiological components can be performed topographically. Further developments and consolidations of these parameters will likely broaden the use of mfERG in the clinical setting.

Section: Retinal Transplantationmentioning

confidence: 85%

Section: Retinal Transplantationmentioning

confidence: 99%

The Clinical Applications of Multifocal Electroretinography: A Systematic Review

Chan

Survey of Ophthalmology

et al. 2007

“…A late macular oedema is described to be a frequent complication after macular translocation surgery or pigment cell transplantation. 7,10 In our series, one patient with geographic atrophy showed delayed vascularisation of the graft and increasing macular oedema after 3 months (Figure 4). Two eyes showed macular oedema at 6-month follow-up due to epiretinal membrane formation.…”

Section: Discussionmentioning

confidence: 55%

“…[2][3][4][5] Simple surgical removal of the membrane did not result in improvement of visual acuity, 6 and attempts to transplant suspensions of retinal pigment epithelial (RPE) cells resulted in a temporary improvement but did not result in a long-term functional monolayer. 7 After 3601 macular translocation, late macular oedema, as well as rapid recurrence of geographic atrophy have been documented. [8][9][10][11][12] Peripheral autologous translocation of the choroid is a novel approach to stabilise visual acuity.…”

Section: Introductionmentioning

confidence: 99%

Optical coherence tomography on autologous translocation of choroid and retinal pigment epithelium in age-related macular degeneration

Joeres

Llacer

Heussen

et al. 2007

Eye

Purpose To analyse structural changes after autologous translocation of choroid and retinal pigment epithelium (RPE) in patients with age-related macular degeneration (AMD) using optical coherence tomography (OCT). Methods We performed a prospective nonrandomised study in 29 consecutive patients, who underwent submacular surgery with translocation of an autologous fullthickness graft of RPE, Bruch's membrane, and choroid. All patients had recent loss of reading vision due to AMD. OCT was performed before surgery and at 3-and 6-month follow-up to analyse the morphological appearance of the graft and the overlying retina. Results Maximum retinal thickness decreased from mean 408 lm (standard deviation (SD) 127 lm) preoperative to mean 373 lm (SD 104 lm) at 6-month follow-up (P ¼ 0.094). In 11 cases (40%), a nearly physiological shape of the retina was seen at this time point. A macular hole persisted in two eyes after silicone oil removal. In most eyes, the highly reflective band of the graft presumably corresponding to RPE was continuous with the surrounding RPE band in all six OCT scans. Eyes with flat appearance of the graft at 6-month follow-up (o300 lm) showed a significantly better functional outcome than eyes with more prominent grafts. Interestingly, most patients did not complain about metamorphopsia, even though the graft was prominent or wrinkled in some cases. Conclusion OCT is a useful tool in monitoring intra-and subretinal changes after subretinal surgery with graft translocation. We demonstrated that graft translocation may lead to a normalisation of retinal thickness and stabilisation of visual acuity.

“…Peripheral RPE cells have been harvested and then transplanted, as a cell suspension, into the same eye post CNV removal. 19,20 Although visual improvement and preservation of retinal thickness have been shown in some patients at follow-up, many other cases have been complicated by extensive PVR, retinal detachment, cell clumping with failure to form an intact monolayer or cell migration.…”

Section: Transplantation Of Adult Rpe Cellsmentioning

confidence: 99%

Replacement of the RPE monolayer

Sheridan

Mason

Pattwell

et al. 2009

Eye

There are numerous scenarios in which replacing the diseased RPE monolayer is an attractive but as yet unrealised goal. The proof of concept that vision can be improved by placing a healthy neuroretina onto a different, healthy, underlying RPE layer is demonstrated in patch graft transplantations. The surgical procedure to relocate the neuroretina is both complex and is hampered by postoperative complications and as such newer replacement procedures are also being investigated including stem cell replacement therapies. Past studies have largely focused on using cell suspensions and have had disappointing outcomes largely due to the lack of control over cellular differentiation, incomplete attachment onto Bruch's membrane and subsequent integration into the existing RPE monolayer. The choice of which cells to transplant is still under investigation and is complicated by factors such as the ease of collection of an adequate sample, rejection following implantation, the age of the cells and ethical issues. In all these situations, however, understanding the mechanisms of cellular differentiation are likely to be prerequisite to future successes. The current research into replacing the RPE monolayer is briefly discussed with reference to our experiences comparing IPE and RPE cells in an in vitro environment.