Vision loss without Amsler grid abnormalities in macular subretinal neovascularization

An 87-year-old woman, with known atrophic senile macular degeneration in one eye, had isolated decreased reading ability while Amsler grid testing was normal. This led to the early diagnosis of macular subretinal neovascularization in the other eye. Thus patients at high risk for neovascular macular degeneration should be made aware of possible subtle changes in vision as well as abnormalities in the Amsler grid. Regular visual acuity check and careful biomicroscopic examination of the macula should be part of each follow-up examination.     

Threshold Amsler grid testing in maculopathies

The Amsler grid is a suprathreshold target and thus may fail to detect relative scotomas. If the grid is viewed through two cross-polarizing filters creating low luminance conditions (threshold Amsler grid testing) the test is far more sensitive. Ten patients with disorders of the macula with normal standard white Amsler grid testing were studied with three other Amsler grid tests. Of the 15 involved eyes, 12 had visual field defects present with threshold Amsler grid testing. Tangent screen examination showed defects in 10 of these 12 eyes. The two red grids used were not as sensitive as the threshold grid. Three eyes had metamorphopsia with the white grid which became the site of a visual field defect with threshold testing. Threshold Amsler grid testing is a rapid and sensitive technique for the evaluation of the central 10 degrees of visual field in patients with maculopathies.     

Replacing the Amsler grid: a new method for monitoring patients with age-related macular degeneration

PURPOSE: To investigate a method that uses hyperacuity, the Macular Computerized Psychophysical Test (MCPT), to evaluate the central macular visual field in patients with age-related macular degeneration (AMD). DESIGN: Prospective case-control study of a diagnostic test. PARTICIPANTS AND CONTROLS: One hundred eight eyes of 108 Patients with AMD and 51 eyes of 51 age-matched patients with no retinal disease. Patients with AMD included 32 (30%) patients with choroidal neovascularization (CNV), 23 (21%) with geographic atrophy (GA), 35 (32%) with AMD with high-risk characteristics (HRC), and 18 (17%) with early AMD with non-HRC. TESTING: Each subject underwent the MCPT, in which a virtual line composed of dots (white dots on a black background, maximal contrast) is flashed across different macular loci to a perifoveal radius of 7 degrees. Patients' responses were recorded and automatically analyzed using a specific algorithm developed before the onset of the study. All patients also underwent a supervised Amsler grid examination on the encounter before or after the MCPT in random order. MAIN OUTCOME MEASURES: Distortion, scotoma, or blurring perceived by the patient after a swift change of fixation was considered positive on the MCPT. Any perception of distortion, scotoma, or blurring was considered positive on the Amsler grid. RESULTS: Of the 32 patients with CNV, 30 (94%) were found positive on the MCPT and 11 (34%) were found positive on the Amsler grid. Of the 23 GA patients, 21 (91%) were found positive on the MCPT and 7 (30%) were found positive on the Amsler grid. Of the 35 HRC patients, 28 (80%) were found positive on the MCPT and 3 (9%) were found positive on the Amsler grid, and of the 18 early AMD with non-HRC patients, 8 (44%) were found positive on the MCPT and 3 (17%) were found positive on the Amsler grid. Of the 51 controls, 3 (6%) were positive on the MCPT and 1 (2%) was positive on the Amsler grid. CONCLUSIONS: The MCPT was superior to the Amsler grid in detecting AMD-related lesions in this cohort. Studies are underway to determine whether the MCPT is feasible for home monitoring to provide early detection of progression to CNV.     

Amsler grid examination and optical coherence tomography of a macular hole caused by accidental Nd:YAG laser injury

PURPOSE: To compare a macular hole from accidental Nd:YAG laser injury with idiopathic macular holes. METHODS: Case report. In a 24-year-old man with accidental Nd:YAG laser injury, right eye, Amsler grid testing and optical coherence tomography were performed. RESULTS: Nd:YAG laser injury was responsible for a macular hole about 700 microm in diameter. The visual acuity was 20/100. Amsler grid testing displayed a central scotoma with no surrounding distortion. Optical coherence tomography showed a defect in all retinal layers at the macula. CONCLUSION: The scotoma caused by Nd:YAG laser injury is not surrounded by distortion; the hole is produced by the defect of all retinal layers. In contrast, idiopathic macular holes generally produce a pincushion pattern on Amsler grid testing and have no tissue loss.     

Threshold Amsler grid testing in diabetic retinopathy

The Amsler grid is a suprathreshold target used to assess the central 10° of the visual field; thus, it may fail to detect relative central scotomas. Low luminance conditions can be created by viewing the white grid on a black background through two cross-polarizing filters that vary light transmission and change the procedure to a threshold Amsler grid (TAG) test, thereby increasing its sensitivity. A total of 26 patients with diabetic retinopathy were tested by standard Amsler grid, TAG, and tangent screen. Four scotomas were detected by Amsler grid testing; each of these scotomas expanded in size on retesting with the TAG. TAG testing revealed 22 scotomas more than five times the number seen with conventional Amsler grid testing; tangent-screen examination confirmed 9 of these defects. In many cases, fundus photography and fluorescein angiography revealed pathology that correlated with the scotomas detected only by TAG testing. It thus appears that the TAG test is a rapid, high-yield, and sensitive means of assessing the central visual field in patients with diabetic retinopathy. Offprint requests to: A.A. Sadun     

Comparison of Preferential Hyperacuity Perimeter (PHP) test and Amsler grid test in the diagnosis of different stages of age-related macular degeneration

BACKGROUND: Age-related macular degeneration (ARMD) is the leading cause of blindness in people over 65 years of age. A rapid loss of vision occurs especially in cases with choroidal neovascularisation. Early detection of ARMD and timely treatment are mandatory. We have prospectively studied the results of two diagnostic self tests for the early detection of metamorphopsia and scotoma, the PHP test and the Amsler grid test, in different stages of ARMD. PATIENTS AND METHODS: Patients with ARMD and best corrected visual acuity of 6/30 or better (Snellen charts) were examined with a standardised protocol, including supervised Amsler grid examination and PHP, a new device for metamorphopsia or scotoma measurement, based on the hyperacuity phenomenon in the central 14 degrees of the visual field. The stages of ARMD were independently graded in a masked fashion by stereoscopic ophthalmoscopy, stereoscopic fundus colour photographs, fluorescein angiography, and OCT. The patients were subdivided into 3 non-neovascular groups [early, late (RPE atrophy > 175 microm) and geographic atrophy], a neovascular group (classic and occult CNV) and an age-matched control group (healthy volunteers). RESULTS: 140 patients, with ages ranging from 50 to 90 years (median 68 years), were included in the study. Best corrected visual acuity ranged from 6/30 to 6/6 with a median of 6/12. 95 patients were diagnosed as non-neovascular ARMD. Thirty eyes had early ARMD (9 were tested positive by the PHP test and 9 by the Amsler grid test), and 50 late ARMD (positive: PHP test 23, Amsler grid test 26). The group with geographic atrophy consisted of 15 eyes (positive: PHP test 13, Amsler grid test 10). Forty-five patients presented with neovascular ARMD (positive: PHP test 38, Amsler grid test 36), 34 volunteers served as control group (positive: PHP test 1, Amsler grid test 5). CONCLUSIONS: The PHP and Amsler grid tests revealed comparable results detecting metamorphopsia and scotoma in early ARMD (30 vs. 30 %) and late ARMD (46 vs. 52 %). However, the PHP test more often revealed disease-related functional changes in the groups of geographic atrophy (87 vs. 67 %) and neovascular ARMD (84 vs. 80 %). This implies that the PHP and Amsler grid self tests are useful tools for detection of ARMD and that the PHP test has a greater sensitivity in the groups of geographic atrophy and neovascular AMD.     

Sine Amsler Charts: a new method for the follow-up of metamorphopsia in patients undergoing macular pucker surgery

PURPOSE: To evaluate our new method for the follow-up of metamorphopsia in patients with a macular pucker. METHODS: Sine Amsler Charts (SAC) are a set of eight modified Amsler charts where we have replaced the straight lines by sine curves of the same frequency but with different amplitudes (grades I-VIII). The patient first examines a regular Amsler chart with the affected eye; subsequently the SAC are presented in random order to the fellow eye. With this eye the patient then selects the SAC with the amplitude that best corresponds to the metamorphopsia observed with the affected eye. After 30 min the test was repeated. A comparison of pre- and postoperative SAC scores was made in 63 patients. The correlations between preoperative visual acuity, membrane type, leakage on fluorescein angiography, preoperative SAC score, postoperative SAC score and postoperative visual acuity were analyzed. RESULTS: Preoperative repeat testing with the SAC revealed 100% reproducibility in the grading of metamorphopsia. Postoperative SAC was unchanged in 16% of cases, one grade lower in 54%, two grades lower in 21% and more than two grades lower in 7%. Postoperative visual acuity was unchanged (i.e., within two EDTRS lines of the preoperative value) in 49% of cases, improved in 48% and decreased in 3%. A decrease in SAC score with a two-line increase in visual acuity occurred in 43% of cases. CONCLUSION: The SAC examination is a reproducible and rapid method for the comparison of the preoperative and postoperative metamorphopsia in patients undergoing pucker surgery and it may serve as an additional outcome measure.     

Visual prognosis in central serous choroidopathy: residual Amsler grid changes

To assess residual changes on Amsler grid charting in central serous choroidopathy, 30 patients (34 eyes) with the disorder were followed from the time of onset of symptoms to the time of resolution of the disease. A total of 28 eyes, including all 3 with an acuity of 6/6 or better, had Amsler grid changes at presentation, compared with 13 eyes at the last follow-up visit. Significantly more patients with a disease duration of more than 8 weeks than those whose disease lasted 8 weeks or less had residual changes (p less than 0.01). Overall, 41% of the eyes had a final acuity of less than 6/6 or a residual change or both.     

玻璃体切除联合自体浓缩血小板封闭 特发性黄斑裂孔疗效观察

目的探讨玻璃体切除联合自体浓缩血小板封闭特发性黄斑裂孔的临床疗效。方法玻璃体切除联合自体浓缩血小板封闭特发性黄斑裂孔手术１４例（１５只眼）,随访３～１６个月,对裂孔封闭情况及视力、视野中心阈值、Ａｍｓｌｅｒ方格表、荧光素眼底血管造影及手术并发症进行观察。结果８６．７％的手术眼裂孔完全闭合,视力增加２行以上者占８６．７％;Ａｍｓｌｅｒ方格表异常者术后视力全部改善;视野中心阈值手术前后差异无显著性（Ｐ＝０．３４）;荧光素眼底血管造影显示部分患眼术后黄斑孔处中央低荧光,其外围以窗样透见荧光环;术中主要并发症为视网膜裂孔,术后主要并发症为白内障加重。结论玻璃体切除联合自体浓缩血小板封闭特发性黄斑裂孔可使大部分患眼裂孔闭合,视力改善,但尚需多中心、大样本研究及长期随诊后进一步加以验证     

Modified grid laser photocoagulation for diffuse diabetic macular edema. Long-term visual results

The authors reviewed the records of 302 eyes of 185 patients with diffuse diabetic macular edema with or without cystoid macular edema treated with modified grid laser photocoagulation between the years 1981 and 1990. Three years after initial grid treatment, visual acuity was improved in 14.5%, unchanged in 60.9%, and worse in 24.6% of eyes. The average number of treatments per eye was 1.9. These results show that in assessing long-term visual outcome, modified grid laser photocoagulation is an effective modality in maintaining or improving visual acuity in eyes with diffuse diabetic macular edema. The effectiveness demonstrated in this study is without comparison with control subjects with no treatment or comparison with other treatment techniques.     

Modified grid laser photocoagulation versus pars plana vitrectomy with internal limiting membrane removal in diabetic macular edema

PURPOSE: To compare the effectiveness of pars plana vitrectomy (PPV) and removal of the internal limiting membrane (ILM) with modified grid laser photocoagulation in diabetic macular edema. DESIGN: Randomized, comparative, interventional study. METHODS: In this prospective study, 24 eyes of 12 patients with bilateral diabetic macular edema were evaluated. PPV with removal of the ILM was performed at random in one eye of 12 patients (ILM group), and a single session of modified grid laser photocoagulation was performed in the fellow eyes (grid group). Main outcome measures were the foveal thickness measured with optical coherence tomography, preoperative, and postoperative visual acuities. Mann-Whitney U and Wilcoxon tests were used in statistical analysis. RESULTS: All patients were followed up for 6 months. In the ILM group, mean foveal thickness was 439.2 +/- 106.5 microm preoperatively and 219.8 +/- 63.2 mum postoperatively (P = .002). In the grid group, mean foveal thickness was 407 +/- 100.2 microm preoperatively and 378.5 +/- 141.6 microm postoperatively (P = .433). A mean decrease in foveal thickness was found to be 219.4 +/- 127.6 microm in the ILM group and 28.5 +/- 90.5 microm in the grid group (P = .001). In the ILM group, best-corrected logMAR visual acuity was 0.75 +/- 0.41 preoperatively and 0.53 +/- 0.41 postoperatively (P = .006). In the grid group, best-corrected logMAR visual acuity was 0.59 +/- 0.27 preoperatively and 0.49 +/- 0.27 postoperatively (P = .058). Visual acuity improved by 2 or more lines in six eyes (50%) in the ILM group and in three eyes (25%) in the grid group. Visual acuity remained stable in six eyes (50%) in the ILM group and in nine eyes (75%) in the grid group. CONCLUSIONS: PPV with ILM removal appears to be more effective than a single session of modified grid laser photocoagulation in the treatment of diabetic macular edema. Further studies with a large number of patients are required for a more reliable conclusion.     

Vitrectomy for idiopathic and secondary preretinal macular membrane

PURPOSE: To evaluate the results of pars plana vitrectomy and membrane stripping for idiopathic and secondary preretinal macular membrane (PMM). MATERIAL AND METHODS: Twenty one consecutive subjects (21 eyes) ranging in age from 40 to 78 (mean 66.9) with PMM underwent vitrectomy and membrane peeling. 17 cases had membranes that were considered idiopathic, and 4 cases were associated with other disorders: 3 occurred after successful retinal reattachment surgery, 1--after laserotherapy in the course of diabetic retinopathy. Visual acuity (VA), Amsler grid, and postoperative complications were assessed. The follow-up was 1 to 22 months, mean 5.7. RESULTS: Visual acuity improved postoperatively in 15 eyes (71.4%), at least two lines on the Snellen chart in 8 eyes (38.1%), entirely in patients with idiopathic PMM. It remained unchanged in 3 eyes (14.3%) and deteriorated in 3 eyes (14.3%). Eyes with transparent membrane showed greater visual improvement than opaque ones. The preoperative Amsler test was positive in 15 patients (71.4%), postoperatively--in 4 cases (19%). 2 idiopathic cases with VA of 0.7 showed postoperatively VA of 1.0. Complications included retinal detachment in 2 eyes (1 in idiopathic and 1 in secondary PMM), and development of nuclear sclerotic cataract in 2 eyes. At 6 months of follow-up, a residual membrane formation in 1 cases appeared. Macular pseudohole was observed in 1 eye with no impact on visual results. CONCLUSIONS: 1. Vitrectomy with membrane peeling for preretinal macular membrane provides improvement in visual acuity and reduces metamorphopsia 2. Thin, cellophane-like appearance of the membrane gives a better prognosis of visual function improvement.     

A modified Amsler grid. A self-assessment test for patients with macular disease

A Modified Amsler Grid, the size of a conventional credit card, has been developed as a suitable alternate to the full-scale version. The size of the grid makes it extremely convenient for patients in our highly mobile society. When viewed twice (vertically and horizontally), it corresponds well to the topography of the central macula. In this capacity the Modified Amsler Grid is a useful adjunct to the overall management of patients with macular diseases which may potentially be associated with exudative manifestations.     

Pars plana vitrectomy and removal of the internal limiting membrane in diabetic macular edema unresponsive to grid laser photocoagulation

PURPOSE: To evaluate the effectiveness of pars plana vitrectomy (PPV) with removal of the internal limiting membrane (ILM) in diabetic patients with macular edema unresponsive to grid laser photocoagulation. METHODS: In this randomized controlled study, 20 eyes of 10 patients with diabetic macular edema unresponsive to grid laser photocoagulation were evaluated. PPV with ILM removal was performed randomly in one eye each of 10 patients and taken as the study group; the untreated fellow eyes were taken as the control group. Main outcome measures were foveal thickness changes measured with optical coherence tomography and preoperative and post-operative visual acuity. Mann-Whitney U, Wilcoxon, and chi-square tests were used in statistical analysis. RESULTS: The mean age of the patients was 61.5+/-6 years (range 51 to 71). All patients were followed up for 12 months. In the study group, mean foveal thickness was 391.3+/-91.6 microm preoperatively and 225.5+/-49.4 microm postoperatively (p=0.009). In the control group, mean foveal thickness was 356.2+/-140 microm at baseline and 318.4+/-111.1 microm at 12-month follow-up (p=0.138). Mean decrease in foveal thickness was 165.8+/-114.8 microm in the study group and 37.8+/-71.2 microm in the control group (p=0.016). In the study group, best-corrected log-MAR visual acuity was 0.71+/-0.43 preoperatively and 0.54+/-0.45 postoperatively (p=0.125). In the control group, best-corrected logMAR visual acuity was 0.43+/-0.44 at baseline and 0.59+/-0.55 at 12-month follow-up (p=0.235). In the study group, visual acuity improved by two or more lines in 4 eyes (40%) and remained stable in 6 eyes (60%). In the control group, visual acuity improved by two or more lines in 1 eye (10%) and decreased by two or more lines in 3 eyes (30%). CONCLUSIONS: PPV with ILM removal appears to be an effective procedure for reducing diabetic macular edema unresponsive to grid laser photocoagulation. A further study with a large number of patients is required to assess the effectiveness and safety of this procedure.     

Modified grid laser photocoagulation for diabetic macular edema. The effect on the central visual field

Modified grid laser photocoagulation has been shown to stabilize visual acuity in patients with diabetic macular edema, but the effect on extrafoveal visual function is uncertain. Automated static threshold perimetry was performed on 64 eyes of 36 patients before and after modified grid therapy with the argon green or krypton red laser. Twenty-eight eyes underwent two grid treatments for persistent macular edema. For all eyes tested, average threshold sensitivity in the central 5 degrees dropped 3.44 dB (standard deviation [SD], 3.79 dB) after the first treatment and 6.86 dB (SD, 5.02 dB) cumulatively after the second treatment. Qualitatively, the grayscale displays of the central visual field were darker after treatment, but the scotomata from laser photocoagulation could not be distinguished from those due to macular edema. The foveal threshold showed no significant change. In a subgroup of patients tested, color vision was not significantly improved and nearly all patients exhibited a tritan defect before and after treatment. No difference was detected between the argon and krypton groups. This suggests that with modified grid laser photocoagulation visual acuity and foveal threshold are preserved at the expense of generalized loss of threshold sensitivity across the central 10 degrees of the visual field.     

Effective treatment of diffuse diabetic macular edema by temporal grid pattern photocoagulation.

BACKGROUND AND OBJECTIVE: To determine the effectiveness of laser grid pattern photocoagulation to the macula but not the papillomacular bundle for the treatment of diffuse diabetic macular edema. PATIENTS AND METHODS: Thirty-five eyes of 23 patients with diffuse diabetic macular edema underwent laser grid photocoagulation excluding the papillomacular bundle area. Best-corrected visual acuity by Snellen chart, foveal thickness using a retinal mapping program by optical coherence tomography (OCT), and mean deviation sensitivity by Humphrey automated central perimetry were investigated before and 1, 3, and 6 months after the treatment. RESULTS: Six months after treatment, the visual acuity was improved by 2 or more lines in 16 eyes (43%) and the foveal thickness decreased in 32 eyes (91%). The mean deviation worsened in 34 eyes (97%). There was a significant correlation between the improvement of visual acuity and the initial mean deviation, suggesting that a better visual acuity would be expected with a preoperative mean deviation of approximately -20 dB. CONCLUSION: Grid pattern photocoagulation without treatment to the papillomacular bundle area was effective in treating diffuse diabetic macular edema, especially in eyes with an initial mean deviation showing moderate dysfunction.     

Results of a multicenter clinical trial to evaluate the preferential hyperacuity perimeter for detection of age-related macular degeneration

PURPOSE: To compare the preferential hyperacuity perimeter (PHP) with an Amsler grid in detection of age-related macular degeneration (AMD). METHODS: Patients underwent refraction, visual acuity examination, PHP, Amsler grid examination, and macular photography. RESULTS: One hundred fifty patients participated in the trial. Of 19 eyes with neovascular AMD, 19 (100%) were positive on the PHP, and 10 (53%), on the Amsler grid. Of 27 eyes with geographic atrophy, 26 (96%) were positive on the PHP, and 12 (44%), on the Amsler grid. Of 20 eyes with intermediate AMD, 14 (70%) were positive on the PHP, and 4 (20%), on the Amsler grid. Of 51 eyes with early AMD, 21 (41%) were positive on the PHP, and 4 (8%), on the Amsler grid. Of 33 eyes with no AMD, 6 (18%) were positive on the PHP, and none, on the Amsler grid. Thus, 80 (68%) of 117 patients with AMD had a positive PHP, while 30 (26%) had positive results of Amsler grid examination (P < 0.001, McNemar test). CONCLUSION: The PHP had greater sensitivity, although with a relatively high rate of false-positive results for healthy individuals, than the Amsler grid in detecting AMD-related lesions.     

Comparison of threshold and standard Amsler grid testing in patients with established antimalarial retinopathy.

To evaluate the sensitivity of threshold Amsler grid testing in the detection of established antimalarial retinopathy, 30 eyes of 15 patients with bilateral, irreversible field defects were examined with the standard Amsler grid and the threshold Amsler grid. Four eyes (13%) showed significant enlargement of large relative scotomas on testing with the threshold Amsler grid. Although only a small proportion of the eyes demonstrated an increase in the size of the scotoma, the patients had established field defects of varying depth, in some cases absolute scotomas. A prospective study in patients with early disease (i.e., with small, shallow scotomas) may be worth while.     

Argon green (514 nm) versus krypton red (647 nm) modified grid laser photocoagulation for diffuse diabetic macular edema

Between 1984 and 1988, 225 eyes of 132 patients were entered in a prospective, randomized clinical trial to determine if any significant differences exist between treatment with argon green (514 nm) and krypton red (647 nm) modified grid laser photocoagulation for patients with diffuse diabetic maculopathy with or without cystoid macular edema. At the 12- and 24-month follow-up visits, no statistically significant difference was found between the two groups with respect to all of the following: reduction or elimination of macular edema, improvement in visual acuity, worsening of visual acuity, number of treatments per eye, and effect on the visual field. At the 12-month follow-up visit, none of the following factors statistically affected the visual outcome in either of the two groups: a history of systemic hypertension, systemic vascular disease, cystoid macular edema, or initial poor visual acuity.     

Long-term results of grid pattern photocoagulation for diffuse diabetic macular edema

PURPOSE: To investigate the long-term results of grid pattern photocoagulation for diffuse diabetic macular edema. SUBJECTS AND METHODS: In 45 cases, 56 eyes foveal thickness and visual outcome were observed 12 months or more after grid pattern photocoagulation. RESULTS: Compared with preoperative values, average foveal thickness decreased significantly during the initial 3 postoperative months and this reduction was maintained through 30 postoperative months. Foveal thickness was reduced by more than 20% in 66% of eyes. The final logarithm of the minimum angle of resolution (logMAR) visual acuity improved 0.2 or more in 41% of eyes. There was a significant correlation between preoperative and postoperative visual acuity. A final visual acuity of 0.5 or better was obtained in 80% of eyes with a preoperative visual acuity of 0.4 or better. There were no eyes with visual loss due to atrophic creep in this study. CONCLUSION: Grid pattern photocoagulation for diffuse diabetic macular edema showed long-term effectiveness in reducing foveal thickness postoperatively. It will be possible to achieve a final visual acuity of 0.5 or better in a high percentage of cases, if grid pattern photocoagulation is performed for those with relatively good visual acuity. The foveal thickness measurement was useful for quantitative evaluation of photocoagulation for diabetic macular edema.