About Us

Thanks for your interest in MyVisionTest. Below is some general information about us, macular degeneration, Amsler grid, and entoptic perimetry. Some of this information is highly technical and is presented for those that want a deeper understanding of the technology that MyVisionTest employs. References are provided for those that are interested in reading more. If your questions are not answered here you are welcome to contact us.

About MyVisionTest
About The Macular Mapping Test
About Macular Degeneration
Further Reading

About MyVisionTest


Amsler Grid

MyVisionTest was developed as a means to assist patients with macular disease in the daily task of monitoring their vision. Research has shown that it is possible through daily vision monitoring to detect the earliest symptoms of progression of macular disease. This is very important because progression of macular disease is potentially treatable, and catching progression at the earliest possible moment decreases the chance of permanent vision loss.

The Amsler Grid
The traditional method of vision monitoring employs a paper chart called the Amsler grid. Unfortunately, there are many shortcomings of the Amsler grid. One of the most serious shortcomings is it's low sensitivity, meaning that it will fail to detect some defects that may be present. One study found that the Amsler grid missed approximately half of the vision defects in patients with macular disease. It is also known that large numbers of patients that are instructed to monitor their vision with the Amsler grid will fail to do so on a regular basis. It is estimated that only half of all patients that are placed on daily Amsler grid monitoring of their vision will comply. Consequently, due to these and other problems with the Amsler grid, many patients that develop complications secondary to their macular disease will fail to detect changes in their vision at the earliest possible moment. Indeed, one study found that only 30% of patients placed on daily Amsler grid vision monitoring that developed choroidal neovascularization (an important and potentially treatable complication of macular degeneration) detected their progression with the Amsler grid.

Entoptic Perimetry
Because of the above problems associated with the Amsler grid, alternatives are actively being sought. Researchers have investigated a number of potential alternatives to the Amsler grid. This research has resulted in some expensive new technology that is currently being used by doctors in their offices to screen patients for macular disease. These instruments, costing thousands of dollars, are unsuitable for patients that need to monitor their vision at home. One inexpensive technology that has been found to be effective in detecting macular disease is known as entoptic perimetry, and it is this technology that is employed by MyVisionTest. Traditionally, entoptic permetry worked by having patients stare at a snowy television screen. Numerous researchers have published papers documenting the effectiveness of this technique to screen for a variety of eye diseases, including glaucoma and macular degeneration. The television is still an effective way to perform entoptic perimetry, although it is far from ideal. It was the desire to improve upon the shortcomings of performing entoptic perimetry on the television that led me to develop MyVisionTest.

MyVisionTest
MyVisionTest is an entoptic perimetry computer program. It is intended to supplement the Amsler grid for patients with macular disease that need to monitor their vision for progression. It is offered free of charge to the public. The vision test and website were developed by Richard Trevino, an optometrist located in Indiana, USA. Although numerous published studies have demonstrated the soundness of entoptic perimetry for the purpose of detecting vision defects caused by macular disease, there are currently no published studies that have employed our computer program. However, we are in discussions with researchers about undertaking such a study. Hopefully, published studies employing MyVisionTest will be forthcoming.

About The Macular Mapping Test

Macular Mapping Test
Macular Mapping Test

The macular mapping test (MMT) was was originally designed primarily for quick assessment of residual vision in patients with maculopathies (MacKeben 2007). However, it also has the potential to be used as a tool for monitoring disease progression (Trauzettel-Klosinski et al. 2003, Bartlett et al. 2005).

The MMT is a computer software program that was originally developed by Manfred MacKeben of the Smith-Kettlewell Eye Research Institute. The test screen displays a constant background pattern throughout the test, that resembled a 'wagon wheel' subtending the central 18 degrees of the visual field (see Figure). Eight spokes point inwards, but do not reach the center of the display area. This pattern is designed to aid the patient with maintaining fixation at the center of the display area during the vision test. Test stimuli are uppercase letters that appear briefly and unpredictably in one of 36 locations on the test screen. The letters are smaller near the center of the screen, and become progressively larger toward the periphery. During the test, the patient fixates the center of the test screen and is asked to identify each letter after it has appeared. There are three possible categories of response; 1) target not detected, 2) target detected, but not recognized (including incorrect responses), 3) target correctly recognized. The final score is calculated using the following system; target not detected = 0, target detected but not recognized = 1, target correctly recognized = 2. The final score is displayed at the end of the test and a 'map' of the areas seen and unseen. The test takes approximately 3 minutes per eye.

Research Studies
Trauzettel-Klosinski and associates (2003) have compared results of MMT with those of manual perimetry using the Tubingen perimeter in 50 patients with a variety of disorders that produce a central scotoma, including AMD, Stargardt's disease, and diabetic maculopathy. To allow direct comparison of the two tests, the investigators divided the central 10 degrees of visual field into 32 sectors, according to the stimulation grid of the MMT. The results of corresponding locations of the tests were compared. Only absolute field defects were analyzed. For perimetry, only the brightest stimulus, and for MMT only "not detected" responses were counted as deficits. Using this approach, the investigators found that correspondence between the two tests was 87.5%, suggesting that there is little difference in the ability of the two tests to detect and delineate dense scotomas. The authors concluded that there was good agreement between MMT and manual perimetry and that MMT is well suited to screen for and monitor the course of patients with macular disease.

Bartlett et al. (2005) has investigated the test-retest variability of the MMT. Thirty-one healthy eyes of 31 normal subjects underwent the test. MMT readings were also taken from 17 eyes of 17 patients with soft drusen, and 12 eyes of 12 patients with geographic atrophy secondary to AMD. The study was designed to assess reproducibility (variability between different examiners), and repeatability (variability with the same examiner). Test-retest repeatability of MMT scores were analyzed by calculating the coefficient of repeatability, which yields the 95% confidence limits for the amount of difference between two sets of results. The average MMT score for the 12 eyes with AMD was 61.9 ± 23.8, and for 16 age-matched controls it was 94.5 ± 4.8 (p < 0.001). MMT scores of patients with soft drusen were not significantly than those of normal age-matched controls. The intra-examiner coefficient of repeatability was ±6.70 and ±7.40 for the two examiners in this study. Between examiners, the coefficients ranged between ±4.3 and ±7.24. Based upon these results, the investigators determined that the MMT score has to change by more than 14 points for the change to be considered clinically significant. They conclude that despite considerable variability, the MMT score could be useful for monitoring progression of AMD.

MMT at MyVisionTest
Our version of the MMT has been modified from the original to enable online self-assessment of central vision for patients with AMD and other macular disease. It is easy to understand, rapid to perform, and yields a quantitative score that can be tracked over time. The MMT appears to as sensitive as manual perimetry in delineating dense scotomas caused by macular degeneration, but whether this holds true for more subtle defects is unknown. Based upon the aforementioned test-retest variability, a loss of 7 test points (scored at 2 points each) is required before disease progression can be confirmed.

About Macular Degeneration

Macular Degeration
Macular Degeneration

There are two types of age-related macular degeneration (AMD): the more common "dry" type, and the less common, but more severe, "wet" variety. Most patients with macular degeneration first develop the dry type, then a few will progress to the more advanced wet stage of the disease. There is currently no cure for age-related macular degeneration, however there are effective treatments that can halt or slow progression, especially for those patients that develop wet macular degeneration.

Dry Macular Degeneration
Dry, or "atrophic", macular degeneration is the most common form of AMD. It is characterized by the accumulation of waste material within the macula (called drusen) and atrophy of macular pigment. Most patients with dry AMD do not experience severe vision loss and many have near-normal visual function. It is, however, possible to progress to a more advanced stage of dry macular degeneration known as "Geographic Atrophy". Patients with this more advanced stage of the disease may suffer severe vision loss. It is also possible for patients with dry macular degeneration to progress to the wet form of the disease. Research has found that the risk of progression can be reduced by consuming certain vitamins, minerals, and other nutrients. Should wet macular degeneration begin to develop often the first symptom is that straight lines may appear wavy (known as metamorphopsia). The Amsler grid was specifically designed to detect this symptom, however, any straight line may reveal metamorphopsia. Patients with macular degeneration should make a point of checking the vision of each eye for metamorphopsia every day. MyVisionTest was developed to assist patients with this task.

Metamorphopsia
Straight Lines Appear Wavy

Wet Macular Degeneration
In those patients that progress to wet, or "exudative", macular degeneration the development of leaking blood vessels within the macula causes severe and rapid loss of vision. It is, however, possible to treat the leaking blood vessels and halt the damage that they cause. For these treatments to be most beneficial it is important to start treatment as soon as possible after the leaking blood vessels appear. To increase the liklihood that progression will be detected early, patients with macular degeneration should make it a habit to check the vision of each eye on a daily basis and have regular follow-up visits with their eye care practitioner.

Further Reading

Amsler Grid

Achard OA, Safran AB, Duret FC, Ragama E. Role of the completion phenomenon in the evaluation of Amsler grid results. Am J Ophthalmol. 1995;120:322-329.

Agustin AJ, Offermann I, Lutz J, Schmidt-Erfurth U, Tornambe P. Comparison of the original Amsler grid with the modified Amsler grid: Result for patients with age-related macular degeneration. Retina. 2005;25:443-445.

Almony A, Garg S, Peters RK, Mamet R, Tsong J, Shibuya B, Kitridou R, Sadun AA. Threshold Amsler grid as a screening tool for asymptomatic patients on hydroxychloroquine therapy. Br J Ophthalmol. 2005;89:569-574.

Amsler M. Earliest symptoms of diseases of the macula. Br J Ophthalmol. 1953;37:521-537.

Amsler M. L'examen qualitatif de la fonction maculaire. Ophthalmologica. 1947;114:248–261.

Crossland M, Rubin G. The Amsler chart: absence of evidence is not evidence of absence. Br J Ophthalmol 2007;91:391–393.

Cheng AS, Vingrys AJ. Visual losses in early age-related maculopathy. Optom Vis Sci. 1993;70:89-96.

Easterbrook M. The sensitivity of Amsler grid testing in early chloroquine retinopathy. Trans Ophthalmol Soc U K. 1985;104:204-207.

Fine AM, Elman MJ, Ebert JE, Prestia PA, Starr JS, Fine SL. Earliest symptoms caused by neovascular membranes in the macula. Arch Ophthalmol. 1986;104:513-514.

Fine SL, Macular Photocoagulation Study Group. Early detection of extrafoveal neovascular membranes by daily central field evaluation. Ophthalmology. 1985;92:603-609.

Fink W, Sadun AA. Three-dimensional computer-automated threshold Amsler grid test. J Biomed Opt. 2004;9:149-153.

Marmor MF. A brief history of macular grids: from Thomas Reis to Edvard Munch and Marc Amsler. Surv Ophthalmol. 2000;44:343-353.

Nazemi PP, Fink W, Lim JI, Sadun AA. Scotomas of age-related macular degeneration detected and characterized by means of a novel three-dimensional computer-automated visual field test. Retina. 2005;25:446-453.

Pluenneke AC, Blomquist PH. Utility of red Amsler grid screening in a rheumatology clinic. J Rheumatol. 2004;31:1754-1755.

Roy MS. Vision loss without Amsler grid abnormalities in macular subretinal neovascularization. Ophthalmologica. 1985;191:215-217.

Schuchard RA. Validity and interpretation of Amsler grid reports. Arch Ophthalmol. 1993;111:776-780.

Wall M, Sadun AA. Threshold Amsler grid testing. Cross-polarizing lenses enhance yield. Arch Ophthalmol. 1986;104:520-523.

Wolfe KA, Sadun AA. Threshold Amsler grid testing in diabetic retinopathy. Graefes Arch Clin Exp Ophthalmol. 1991;229:219-223.

Zaidi FH, Cheong-Leen R, Gair EJ, Weir R, Sharkawi E, Lee N, Gregory-Evans K. The Amsler chart is of doubtful value in retinal screening for early laser therapy of subretinal membranes. The West London Survey. Eye. 2004;18:503-508.

Entoptic Perimetry

Adachi M, Shirato S. The usefulness of the Noise-Field Test as a screening method for visual field defects. Jpn J Ophthalmol. 1994;38:392-399.

Aulhorn E, Köst G. Rauschfeldkampimetrie: eine perimetrische Untersuchungsweise. Klin Monatsbl Augenheilkd. 1988;192:284-288.

Brown JC, Kylstra JA, Mah ML. Entoptic perimetry screening for central diabetic scotomas and macular edema. Ophthalmology. 2000;107:755-759.

El-Bradey M, Plummer DJ, Uwe-Bartsch D, Freeman WR. Scanning laser entoptic perimetry for the detection of visual defects associated with diabetic retinopathy. Br J Ophthalmol. 2006;90:17-19.

Freeman WR, El-Brady M, Plummer DJ. Scanning laser entoptic perimetry for the detection of age-related macular degeneration. Arch Ophthalmol. 2004;122:1647-1651.

Plummer DJ, Azen SP, Freeman WR. Scanning laser entoptic perimetry for the screening of macular and peripheral retinal disease. Arch Ophthalmol. 2000;118:1205-1210.

Plummer DJ, Banker A, Taskintuna I, Azen SP, Sample PA, LaBree L, Freeman WR. The utility of entoptic perimetry as a screening test for cytomegalovirus retinitis. Arch Ophthalmol. 1999;117:202-207.

Schiefer U, Gisolf AC, Kirsch J, Selbmann HK, Zrenner E. Rauschfeld-Screening Ergebnisse einer Fernsehfeldstudie zur Detektion von Gesichtsfelddefekten. Ophthalmologe. 1996;93:604-616.

Shirato S, Adachi M, Hara T. Subjective detection of visual field defects using home TV set. Jpn J Ophthalmol. 1991;35:273-281.

Macular Mapping Test

Bartlett, H., Davies, L. and Eperjesi, F. (2005) The macular mapping test: a reliability study. BMC Ophthalmol. 5, 18. Free full text

MacKeben, M. (2007) Macular Mapping Test, Smith-Kettlewell Eye Research Institute, San Francisco, viewed 31 December 2007.

Trauzettel-Klosinski, S., Biermann, P., Hahn, G. and Weismann, M. (2003) Assessment of parafoveal function in maculopathy: a comparison between the Macular Mapping Test and kinetic manual perimetry. Graefes Arch. Clin. Exp. Ophthalmol. 241, 988-995.

Others Macular Function Tests

Alster Y, Bressler NM, Bressler SB, et al; Preferential Hyperacuity Perimetry Research Group. Preferential Hyperacuity Perimeter (PreView PHP) for detecting choroidal neovascularization study. Ophthalmology. 2005;112:1758-1765.

Goldstein M, Loewenstein A, Barak A, et al; Preferential Hyperacuity Perimeter Research Group. Results of a multicenter clinical trial to evaluate the preferential hyperacuity perimeter for detection of age-related macular degeneration. Retina. 2005;25:296-303.

Kampmeier J, Zorn MM, Lang GK, Botros YT, Lang GE. Vergleich des Preferential-Hyperacuity-Perimeter (PHP)-tests mit dem Amsler-netz-test bei der diagnose verschiedener stadien der altersbezogenen makuladegeneration. Klin Monatsbl Augenheilkd. 2006;223:752-756.

Klatt C, Sendtner P, Ponomareva L, Hillenkamp J, Bunse A, Gabel VP, Roider J. Diagnostik von metamorphopsien bei netzhauterkrankungen unterschiedlicher genese. Ophthalmologe. 2006;103:945-952.

Kuchenbecker J, Lindner H. Visual function tests on the Internet--sense or nonsense? Strabismus. 2004;12:97-102.

Loewenstein A, Malach R, Goldstein M, Leibovitch I, Barak A, Baruch E, Alster Y, Rafaeli O, Avni I, Yassur Y. Replacing the Amsler grid: a new method for monitoring patients with age-related macular degeneration. Ophthalmology. 2003;110:966-970.

Teich SA, Saltzman BR. Evaluation of a new self-screening chart for cytomegalovirus retinitis in patients with AIDS. J Acquir Immune Defic Syndr Hum Retrovirol. 1996;13:336-342.