Improvement in near visual function after macular translocation surgery with 360-degree peripheral retinectomy

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1 Graefe s Arch Clin Exp Ophthalmol (2004) 242: CLINICAL INVESTIGATION DOI /s Cynthia A. Toth Deborah J. Lapolice Avie D. Banks Sandra S. Stinnett Improvement in near visual function after macular translocation surgery with 360-degree peripheral retinectomy Received: 9 September 2003 Revised: 7 January 2004 Accepted: 8 January 2004 Published online: 5 June 2004 Springer-Verlag 2004 C. A. Toth ()) D. J. Lapolice A. D. Banks S. S. Stinnett Department of Ophthalmology, Duke University Medical Center, Box 3802, Durham, NC 27701, USA toth004@mc.duke.edu Tel.: Fax: C. A. Toth Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA S. S. Stinnett Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, North Carolina, USA Abstract Background: Information is limited on how specific near-vision skills are impacted by therapies such as macular translocation surgery with 360-degree retinectomy (MT360) for age-related macular degeneration (AMD). Methods: Standardized tests of near vision were given to 25 consecutive patients with AMD who met entry criteria for this study, preoperatively and 6 and 12 months after MT360. Tests included: near acuity with the Lighthouse chart, timed reading speed using Sloan cards, contrast sensitivity, and color vision. Distance acuity was measured using Bailey Lovey charts. Measures of preoperative visual function were analyzed to identify those predictive of visual outcomes. Results: Distance acuity was 20/80 or better in 52% of patients at 12 months after surgery, and mean acuity improved from ~20/125 preoperatively to ~20/100 at 12 months. Mean near acuity improved from M before surgery to M at 12 months (significant change of Ÿ1.5 2 M, P<0.001). Gain of greater than five numbers in contrast sensitivity at 12 months was also significant (P<0.001). Mean reading speed improved from words per minute (wpm) before surgery to wpm at 12 months (significant gain of wpm, P=0.001). Preoperative distance acuity, near acuity, and reading speed were each predictors of postoperative near visual function. Conclusion: Standardized testing of near visual function provides important predictive and functional outcome data for MT360. MT360 significantly improved near visual function (including near acuity, reading speed and contrast sensitivity) in patients with subfoveal lesions from AMD in the second eye. Introduction Near visual function, that is the ability to see items at near and to read, is highly valued in our society, as demonstrated in studies of low vision and quality of life. Reading is the primary rehabilitation goal of patients with low vision and central field loss [7, 10, 13, 14, 21]. In questionnaires, patients equate near visual functioning and perceived reading ability to perceptions of a visual disability [10, 18]. Reading ability has a significant positive correlation with quality of life, and reading speed has been shown to be the most important factor for general visual quality of life [10]. Numerous measures have been used to assess near visual function in patients with low vision and with agerelated macular degeneration (AMD) [3]. Testing of near visual function has covered a wide range of abilities, recognition of from single letters and numbers to reading ability in a variety of print sizes. Despite the range of available near-vision tests, there is limited information on how specific near-vision skills are impacted by therapies for AMD. Clinical trials of treatments for AMD, notably the Macular Photocoagulation Study (MPS) and the Treatment of Age-Related Macular Degeneration With Photodynamic Therapy study, have not reported outcomes in terms of reading speed or using other tests of near visual

2 542 function. The Submacular Surgery Trials (SST), sponsored by the National Eye Institute, included tests of reading speed in study patients with subfoveal choroidal neovascularization or hemorrhage [22]. This study used as a measure the time to read single-size, large-print text cards of approximately 17.5-meter text, equating to a distance acuity of approximately 20/1500 (personal communication with Barbara Hawkins, SST Headquarters). The SST is ongoing, and the near-vision results have not yet been reported. Macular translocation surgery with 360-degree peripheral retinectomy (MT360) was first reported by Robert Machemer in 1992 at the Club Jules Gonin in Vienna, Austria. The reported goal of macular translocation surgery was to recover central acuity by moving the macula away from the region of subfoveal pathology. In the early series of patients reported by Machemer, some patients recovered distance and near vision, although there was a high rate of retinal detachment and proliferative vitreoretinopathy [16]. Numerous surgeons have subsequently modified and varied the Machemer technique for the treatment of patients with choroidal neovascular membranes beneath the macula and vision loss [6, 9, 12]. Claus Eckardt in 1999 reported improvement in reading ability in a majority of patients who were treated with MT360 [6]. Lai et al. reported a significant improvement in near acuity at 6 months and a tendency towards improvement in reading speed that was not significant (using SST large-print reading cards) after MT360 in a series of 15 patients in the Duke Macular Translocation Study [12]. Fujikado et al. reported a significant improvement in critical print size after MT360, although the change in reading speed was not significant [9]. Clearly there is a limitation of the large-print cards for testing the reading function in macular translocation patients, and there is a need for comprehensive evaluation of macular function, including acuity, reading speed with near print tests, color vision, and contrast sensitivity before and after MT360 surgery. We therefore utilized standardized tests for these factors, including reading ability and near visual function, in a series of 25 patients in the Duke Macular Translocation Study. In this prospective non-randomized study of patients with central vision loss in the second eye due to subfoveal choroidal neovascularization, we analyzed the impact of MT360 on the results of multiple tests of visual function and evaluated the utility of these tests in predicting postoperative visual function. Methods Twenty-five consecutive patients participating in an IRB-approved study of macular translocation surgery at Duke University Medical Center who met the entry criteria for this study participated in the evaluation of near vision recovery. The patients entered the study between October 2000 and July Eligibility criteria for the macular translocation surgery study included, AMD and the loss of vision in the fellow eye due to CNV or disciform scar. The treatment eye was required to have: 1. Subfoveal neovascular AMD with no previous subfoveal laser or previous ocular photodynamic therapy 2. Lesion components including classic CNV, occult or combination of classic and occult CNV with no limit to the amount of subretinal hemorrhage, RPE atrophy, pigment epithelial detachment or subretinal fibrosis 3. No chorioretinal anastomosis 4. Duration of vision loss less than 6 months 5. Best-corrected Snellen acuity worse than 20/60 before study entry At examinations before operation, 6 months postoperatively, and 1-year after operation, the patients had complete vision testing including distance and near acuity. Distance visual acuity was measured using the SST protocol and using the retro-illuminated Bailey Lovey charts under standard illumination conditions [12]. Testers of postoperative vision were not masked to the preoperative results, though the previous data sheets were not available to the tester at the time of testing. Near acuity testing was performed in a single setting with standard illumination using the Lighthouse near card (Lighthouse, New York, NY) with add over distance correction. Text size was reported in meters of text (e.g., 10 meters or 1.0 meter) measured on the card. This lsize of text was then provided to the patient in the form of a continuous-text Sloan reading card in order to measure reading speed at the patient s preferred focal distance, still using the add correction. Additionally, the patients were asked whether they were functionally reading at home ; for example, they were asked to specify whether they were able to read books, magazines, or mail. Contrast sensitivity was measured using the LEA near-contrast cards (Precision Vision, La Salle, IL) in which contrast becomes lower with each number on the chart. The grading for contrast sensitivity was by number count, ranging from zero numbers read correctly to a top score of 30 numbers. Color vision was assessed using the PV16 discs (Precision Vision). The color test results were categorized into the following grades: grade 5, all 16 discs in correct order; grade 4, three or fewer discs incorrectly placed by one place; grade 3, one color family, but fewer than five discs, incorrect; grade 2, two color families incorrect with fewer than six discs incorrect; grade 1, more then two color families incorrect but at least three discs correct; grade 0, all plates incorrect. The patients also underwent fluorescein angiography at each study visit. The lesion sizes and components were assessed from the fluorescein angiograms using MPS disc area rings measuring 1, 2, 3, 3.5, 4, 5, 6, 9, 12, and 16 MPS disc areas [17]. The sizes of lesions greater than 16 MPS disc areas were estimated using several rings. Patients also completed quality of life evaluations and underwent optical coherence tomography pre- and postoperatively. Analysis of quality of life and optical coherence tomography data will be reported separately. Statistical methods Initially, descriptive statistics (n and percentage for categorical variables; n, mean, standard deviation, median, minimum, and maximum for continuous variables) were obtained and displayed. Change from baseline to 6 months and to 1 year was computed for distance and near visual acuity, reading speed, color, and contrast. The significance of the change was assessed using the Wilcoxon signed ranks test. Spearman rank correlation was computed to assess the relationship between the values of these variables at

3 543 baseline and their values at 6 months and at 1 year. In addition, linear regression was used to assess the individual predictive abilities of each preoperative measure (distance and near visual acuity, reading speed, color, contrast, duration of lesion, and size of lesion) for postoperative visual acuities and reading speed (at 6 months and at 1 year). The ranks of both predictor and dependent variables were used in the regression analyses. McNemar s test was used to assess the agreement between 6-month and 1-year outcomes in preferred eye and ability to read. Results There were 16 females and 9 males in this study, with a median age of 77 years (range years). The median duration of vision loss was 6 weeks, with a range of 1 24 weeks. The preoperative median visual acuity in the fellow eye was 20/320, with a range of 20/50 to 20/8000. All patients had a history of AMD and all had a choroidal neovascular membrane beneath the fovea in the treatment eye. The mean lesion size was 8 MPS disc areas (~2900 mm), with classic CNV comprising greater than 50% of the lesion in 20% of eyes. All patients participated in the 6-month follow-up testing, and 24 of 25 patients returned for 1-year followup testing. One patient did not return for 1-year follow-up due to inability to travel. Her local ophthalmologist provided a written report of Snellen distance acuity of 20/40 in the treated eye at 1 year after MT360. Because her 1- year Snellen acuity was the same as her acuity at 6-month standardized testing at Duke, for data analysis, her 6- month distance acuity score was brought forward for the 1-year data point. Near acuity was not formally tested at her 1-year outside examination, and thus it was not included in the 1-year analysis. The patient reported an ability to read using her 6-month-old reading glasses at home at 1 year. Mean distance acuity for the 25 patients was letters (20/125 Snellen standard deviation) preoperatively and letters 6 months postoperatively, and improved to letters (20/100 Snellen) at 1 year after MT360 (Fig. 1). The mean change in distance acuity was a gain of letters at 6 months after MT360 and a gain of letters at 1 year. This change from the preoperative acuity was not significant (P=0.89 for 6 months and P=0.32 for 1 year; Wilcoxon signed ranks test). At 1 year, 28% of patients had gained 20 or more letters of acuity in the operated eye, 12% had gained 5 14 letters of acuity, 24% remained within 4 letters of preoperative acuity, 28% had lost 5 14 letters of acuity, 8% had lost letters of acuity, and 0% had lost more than 18 letters of acuity. Distance visual acuity was greater than or equal to 20/80 in 44% of patients preoperatively, 48% of patients at 6 months, and 52% of patients at 1 year after MT360. Near visual acuity before and after MT360 is summarized in Fig. 2. Using the meter (M) scale for near Fig. 1 Distance acuity before surgery is compared to 1 year after macular translocation 360 surgery. Distance acuity was measured using the Bailey Lovey chart; thus, the scale is number of letters correctly read. Fifty letters is equivalent to approximately 20/200 Snellen acuity. The improvement in distance acuity was not significant Fig. 2 Near acuity before surgery is compared to 1 year after MT360 surgery. Near acuity recorded in Meter print size, using Lighthouse near cards and add over best correction for distance visual acuity (a large number corresponds to a larger letter size). The improvement in near acuity was significant at 1 year (P<0.001) acuity, a large number corresponds to a larger letter size. The mean near acuity in the 25 patients was M before surgery and had improved to M by 6 months; it improved to M in the 24 patients tested at 1 year after MT360. The mean change in near acuity was Ÿ M at 6 months and Ÿ M at 1 year. The change in near visual acuity was significant both at 6 months and at 1 year (P<0.001; Wilcoxon signed ranks test).

4 544 Fig. 3 Reading speed before surgery is compared to 1 year after MT360 surgery. Reading speed recorded as words per minute at near using Sloan cards and add over best refraction for distance. Improvement in reading speed was significant at 1 year (P=0.001) Fig. 4 Contrast sensitivity before surgery is compared to 1 year after MT360 surgery. Contrast sensitivity recorded at near using LEA contrast cards and add over best refraction for distance. Improvement in contrast sensitivity was significant at 1 year (P<0.001) Fig. 5 Color vision grade using the PV-16 color discs before surgery is compared to 1 year after MT360 surgery. The improvement in color vision at 1 year was not significant (P=0.12) The results of testing reading speed with a add over distance correction are summarized in the graph Fig. 3. The average reading speed in the 25 patients was words per minute (wpm) before surgery and improved to wpm at 6 months; it improved to wpm in the 24 patients tested at 1 year after MT360. Reading speed at 6 months improved by wpm, and at one year improved by wpm. This change in reading speed was statistically significant at 6 months (P=0.013) and 1 year (P=0.001) (Wilcoxon signed ranks test). Before MT360 surgery, 32% of patients read over 40 wpm, but only 16% of patients read more than 70 wpm. At 6 months after surgery, 56% of patients read over 40 wpm and 32% read over 70 wpm. At 1 year after surgery, 67% read over 40 wpm and 38% read over 70 wpm. By self-report, 88% of patients preferred the treatment eye for visual functioning before and 1 year after MT360 surgery. Before surgery only 16% of patients reported being able to read at home, whereas postoperatively 64% at 6 months and 80% at 1 year reported being able to read at home. There was a statistically significant increase in the proportions of patients able to read at the two time points (P<0.001; McNemar s test for agreement). All patients who could read before surgery continued reading at 6 and 12 months after MT360. Of the 21 patients who could not read preoperatively, 12 patients at 6 months and 16 patients at 1 year were able to read. Contrast sensitivity results are seen in Fig. 4. The mean number of contrast numbers correctly read by the 25 patients was before surgery and increased to numbers at 6 months; the 24 patients tested at 1 year correctly read numbers. Contrast sensitivity gained by numbers at 6 months and numbers at 1 year. The change in contrast sensitivity was statistically significant at both 6 months and 1 year (P<0.001; Wilcoxon signed ranks test). Color vision results are seen in Fig. 5. The mean color vision score by PVS 16 color vision grade was before surgery. It improved to in the 25 patients tested at 6 months after surgery and to in the 24 patients tested at 1 year after surgery. The change in color vision was not significant at either 6 months or 1 year (P=0.09 for 6 months and P=0.12 for 1 year; Wilcoxon signed ranks test). At 1 year, no patient had dropped by more than one color group; 25% of patients had lost one

5 545 color group, 33% maintained the same color group score, and 42% gained by one to three color groups. Preoperative distance visual acuity, near visual acuity and reading speed were predictive of postoperative vision outcomes. Significant predictors of distance visual acuity at 1 year were preoperative measures of distance acuity (P=0.011, positive direction) and near acuity (P=0.006, negative direction: note that only in the scale used for near vision, a lower grade was assigned to better acuity). Thus, better preoperative distance or near acuity predicted better postoperative distance visual acuity. Significant predictors of near visual acuity at 1 year were preoperative measures of distance acuity (P<0.001, negative direction), near acuity (P<0.001, positive direction), and reading speed (P=0.027, negative direction). Thus, better preoperative distance or near acuity or reading speed predicted better postoperative near acuity. Significant predictors of reading speed at 1 year were preoperative measures of distance acuity (P=0.007, positive direction), near acuity (P=0.011, negative direction), and reading speed (P=0.031, positive direction). Thus, better preoperative distance acuity, near acuity, and reading speed predicted better postoperative reading speed. The preoperative color vision grade, contrast sensitivity score, lesion size, and duration of vision loss were not significant predictors of distance visual acuity, near visual acuity, or reading speed at 1 year. Preoperative reading speed was not a significant predictor of distance visual acuity at 1 year. In this series, the following complications occurred: 28% of patients had cystoid macular edema found on either fundus examination, fluorescein angiography, or optical coherence tomography; 36% had recurrent choroidal neovascularization, with extension into the fovea in 20%; 28% had epiretinal membrane. Three patients had at least one subretinal droplet of perfluorocarbon liquid, although none was in the fovea; and no patient had a macular fold. There were two retinal detachments involving the inferior retinal margin without macular detachment. Both patients had surgical repair of the retinal detachment. Both retinal detachments were identified after silicone oil was removed. Discussion Eckardt et al. in 1999 were the first to report reproducible improvement in distance and near acuity and reading ability after MT360 surgery [6]. In that retrospective review and in other studies of MT360, near visual function was ascertained by direct observation or by noting the report of the patient as to whether he or she could read [1, 2, 6, 19] Lai et al. [12] and Fujikado et al. [9] studied the impact of MT360 surgery on distance and near acuity and reading speed, using standardized tests of distance acuity (Bailey Lovey Charts, Lai et al.; Landolt Cs, Fujikado et al.), near acuity (Jaeger cards, Lai et al.; Landolt Cs, Fujikado et al.) and reading speed (SST large print cards, Lai et al.; Japanese version of the Minnesota reading chart, Fujikado et al.) before and after MT360. Both groups found no significant change in distance acuity and in reading speed after MT360. However, they each found a significant improvement in one measure of near acuity. Fujikado et al., in AMD patients from 4 to 15 months after surgery, found a significant improvement in critical print size after MT360. Lai et al. found significant improvement in near acuity at 6 months after MT360. In the present small prospective non-randomized series of patients subsequent to the Lai series, we have shown a beneficial effect of MT360, with improvement in distance and near acuity in the majority of patients. These outcomes are an improvement over the earlier report of Toth and Freedman, most likely due to the improvement in surgical techniques and the surgeons extended experience since the earlier study [22]. Moreover, in the current study, we have also detailed the improvements in multiple aspects of near visual function after MT360, including reading speed, contrast sensitivity, and color vision. In this study, the improvements in near visual acuity, contrast sensitivity, and reading speed were statistically significant. These patients also reported an improvement in ability to read at home that was consistent with the improvement in near vision measured in our clinic. These data support the hypothesis that MT360 surgery can shift the sensory retina away from dysfunctional support tissue and onto an adequate bed of choroid and RPE with recovery of central visual function. In the clinical experience of one author (D.J.L.), as well as in published studies on near vision testing, central visual field loss is associated with poor reading ability defined by significant decreases in reading speed [8, 13]. Many ocular factors affect the reading speed, including print size, contrast, field of view, and size and location of scotoma [8, 13, 14, 21, 25]. The scotoma location is a major factor for macular degeneration patients, since reading rates are reduced severely when a scotoma is centered on the fovea. These rates are also significantly reduced when a scotoma is displaced either to the left or right of the fovea. Patients with central scotomas adopt eccentric viewing behaviors, and their reading rates decrease to about 25% of those in scotoma-free conditions [13]. Maximum reading speed in peripheral vision is limited by the reduced number of characters that can be recognized in a glance (visual span). Chung et al. reported that visual span decreases from 10 characters in central vision to 2.8 characters at 15 deg eccentric to central fixation) [5]. Further studies showed that reading speed of greater than 80 wpm is not possible using eccentric fixation with the presence of a central scotoma. Whittaker and Lovie- Kitchin reported that 160 wpm is a high fluent rate for reading, 80 wpm is fluent, and 40 wpm is adequate only

6 546 for spot reading [25]. Using the 40-wpm standard, our patients improved from only 32% spot reading preoperatively to over 67% spot reading at 1 year. It is interesting to compare this to the self-reported ability to read at home, with 16% reading preoperatively and 80% reading at 1 year. We believe that the improvement in near visual function, particularly the ability to read after macular translocation surgery, is due to resolution of density or extent of the central scotoma once the macular photoreceptors are positioned over the new healthier RPE choriocapillaris bed. In the present study, the improvement in reading speed and contrast sensitivity, the proportion of patients with a good postoperative reading speed, and the small print size that these patients could read all support the premise of improvement in macular function and decrease in central scotoma after macular translocation surgery. Microperimetry studies, not performed in these patients, would better define the evolution of central and paracentral scotomas affecting reading speed. We have subsequently initiated use of microperimetry in studies of macular translocation surgery patients, to better understand the impact of scotoma density and location on visual function. Other measures of retinal function, such as electroretinography (ERG), were not performed in our study. Other researchers have addressed ERG changes after macular translocation surgery. Lüke et al. evaluated photopic and scotopic ERG of 32 patients before and after MT360 [15]. (Note that they used a calcium- and magnesium-free solution to detach the retina during surgery). In their series, the mean logmar visual acuity had decreased by only 0.13 at the time of the approximately 6- month postoperative ERG (not a significant change), but amplitudes of both a- and b-waves for both photopic and scotopic ERG were reduced. The authors proposed that surgical techniques or the calcium- and magnesium-free infusion solution might relate to the diminished ERG amplitudes in their series. Terasaki et al. also found diminished ERG amplitudes after MT360 in a series of 15 patients, all of whom had improved acuity after MT360 [23]. The negative impact of AMD on cone function and thus on color vision has been measured, although treatments of AMD to date have not had a notable impact on color vision function [4, 11, 20]. In this study, there was a trend toward improvement in color vision after the macular photoreceptors were relocated off the pathologic lesion, with 42% of patients gaining one to three color groups after surgery. The small number of patients in our series, however, and the large steps in the color vision grading scale, limit our ability to identify small changes in color vision function. The improvements in near acuity, reading speed, and contrast sensitivity after MT360 surgery appear to be greater than the distance improvement. A likely explanation for this difference in near visual function relative to distance acuity is the very complex interaction between the density, location, and size of a central scotoma, color vision, and contrast sensitivity and the reading speed. As numerous researchers have shown, each of these factors has an impact on near function and reading ability [3, 4, 5, 8, 10, 13, 14, 18, 19, 21, 25]. It is unclear why the improvement in distance acuity is less than that in near acuity after MT360. In addition to the above factors, the extraocular muscle surgery may cause some limitation in microsaccades utilized in reading the distance ETDRS chart. The level of distance and near acuity at 1 year, and the paucity of severe vision loss after MT360, also supports the premise that MT360 is a reasonable therapeutic option for patients losing vision in the second eye from large subfoveal CNV. In addition to the improvement in near visual function reported above, after surgery, 48% and 52% of patients achieved a distance visual acuity of 20/80 or better at 6 months and 1 year respectively. Fewer than 8% of patients lost more than 3 lines of distance visual acuity and no patient lost more than 4 lines of distance visual acuity. These results are particularly notable as they were achieved in patients with mean acuity of 20/125 and subfoveal lesion size of 8 MPS disc areas at study entry. Complications of the challenging macular translocation surgery are numerous, including retinal detachment, macular edema, and recurrence of CNV, but patients generally had a significant improvement in near visual function despite these challenges. The number of patients in this study was too small to identify any specific complications that might have affected the visual outcomes. There were two macula-sparing inferior retinal detachments in this series of 25 patients (8%). Retinal detachment was not associated with poorer visual acuity in this series. Future improvements in surgery may decrease the likelihood of such complications and/or improve their management, and thus would be anticipated to improve visual outcomes. It is important to identify factors that aid in predicting outcomes after MT360 surgery as these factors could be utilized by a surgeon to predict more accurately the likelihood of good visual outcomes for a patient. After evaluating the impact of preoperative factors on visual outcomes, we found that both preoperative near and distance visual acuity predicted postoperative near and distance acuity and reading speed in our series; in contrast, preoperative reading speed was predictive only of postoperative near acuity and reading speed. Patients with very poor near and distance acuity and reading speed were thus less likely to exhibit good postoperative visual function. These predictive relationships may be due to the association of these factors with the severity and extent of photoreceptor damage before surgery. More extensive or

7 547 severe damage would be reflected in poorer preoperative scores and might be associated with less photoreceptor recovery after translocation to a healthier RPE bed and thus result in a lower likelihood for good postoperative visual function. Alternatively, poor preoperative scores may also reflect greater preoperative scarring between the submacular lesion and photoreceptors. Thus, poor preoperative scores might predict a greater likelihood for photoreceptor injury with surgical separation of the retina from the subretinal lesion. We had also hypothesized that the preoperative color vision grade and contrast sensitivity score might predict macular function and thus identify patients likely to have a good visual outcome. These two factors, however, did not predict reading speed or near or distance acuity outcomes in this series. While these factors may genuinely not affect such outcomes, our sample size may also have been too small and the gradations in measurement for these factors may have been too large to identify any impact. Duration of vision loss by patient report, and the lesion size measured from the preoperative fluorescein angiogram, also did not predict the acuity or reading speed after surgery. We believe that improvement in functional near visual acuity is achievable after macular translocation surgery with 360 peripheral retinectomy in patients treated by a team experienced in this surgical technique. This study was performed without a control group. Future randomized studies comparing this treatment to current regimens utilized for eligible patients with bilateral severe macular degeneration will clarify the relative impact of this treatment on a patient group severely impaired by this ocular disease. Information gained from the recovery of visual function after translocation of the neurosensory retina to a healthier choriocapillaris and RPE bed may add to our understanding of the impact of scotoma density and location upon useful vision recovery. This information may also aid in identifying relative photoreceptor versus RPE contribution to the progression of vision loss in AMD, and in designing non-translocation techniques for retinal recovery, such as repopulating healthy RPE beneath the macula. Acknowledgements The authors would like to thank Katrina P. Winter, Mikki R. O Neal and Michelle N. McCall for their assistance in manuscript preparation, data gathering, and data analysis. This work was supported in part by the generous donations of the Andrew Family Foundation (Boston, MA) and Euan and Angelica Baird (New York, NY). References 1. 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