Interactive Amsler grid

The Interactive Amsler grid (digital Amsler Grid) is an electronic version of the ophthalmic applied Amsler grid . With the Amsler grid, only a qualitative recording is possible, but no quantitative (numerical) measurement. This complicates a follow-up with the Amsler grid. The electronic tests try to remedy this deficit using different approaches.

Diseases

View in the visual field of an AMD patient

A distorted visual impression can be a symptom of various eye diseases. In so-called age-associated macular degeneration (dry and moist form), macular edema (e.g. as a result of diabetes , venous thrombosis, myopia or uveitis ) and in epiretinal gliosis or macular holes, objects can be perceived as distorted. As long as they are only minor, and especially if they only occur in one eye, these distortions can be compensated for by the brain and may not be noticed by the person concerned. In the course of the untreated disease, the patient sees straight lines increasingly distorted.

In 2015 there were 6.5 million diabetics (type I and II) in Germany, which corresponds to approx. 4.7–5.6% of the population. Retinal changes as a result of diabetes ( diabetic retinopathy ) occur in around a third of diabetics. According to a forecast by the International Diabetes Federation IDF, 642 million people will be diagnosed with diabetes in 2040.

Retinal diseases are a leading cause of acquired visual impairment in adults of working age, causing 37 million blindnesses worldwide. While about 35% of all diabetics have diabetic retinopathy, vision in 7% is threatened by diabetic macular edema (moisture accumulation in the center of the retina) or severe proliferative changes in the retina (formation of diseased blood vessels). In rural areas, diabetic retinal changes are more common. The authors of two studies conclude that access to screening options is more difficult there and see this as an area of ​​application for retinal screening using telemedicine .

Age-associated macular degeneration is one of the relatively unknown widespread diseases despite its high number. In Germany, around 4.5 million people are affected by both forms (dry and wet form). In addition, there are around 7 to 8% of diabetics who also develop macular edema in the course of their illness. This increases the total number of people affected by macular edema to around 5 million (in Germany in 2015).

Quantitative method

These methods enable precise progress documentation as they provide values ​​for the strength of the distortion, the eccentricity (distance to the center) and the area of ​​the distortion.

A Metamorphopsia Detector

Distortion measurement with approximated lines

Distortions drawn in by the patient

The patented device DE 10 2015 215 557 / program can quantitatively record distortions.

If lines are perceived as being distorted, these lines can be straightened with the help of the computer mouse / finger / pen. Straight lines are shown on the screen in a horizontal or vertical arrangement. The observer can change a line that is perceived as distorted until it appears straight to him. For a healthy eye, a straight line becomes a distorted line: the observer has shifted the line in the other direction in which he saw it distorted and has thus created a negative image of his distortion.

execution

The patient uses the computer mouse or the finger / pen to straighten those lines that he perceives as distorted when looking at a grid on the screen at a specified distance from a monocular (one-eyed) view. An index reflects the amplitude (d), position (ε) and extent (A) of the distortions and is used to monitor progress.

The interactive metamorphopsia measurement enables the patient and the ophthalmologist to work together, because with the appropriate programs, quantitative documentation of the distortions is also possible as a home test and the result can be encrypted and sent to the doctor.

3D view of the distortions drawn by the patient

Quantitative methods make it possible to calculate a 3D image from the negative image created by the patient of his distorted perception. The measurement of these functional disorders (distorted visual impression, absolute or relative scotoma) reflects anatomical changes that can be visualized using optical coherence tomography (OCT).

Executions

The test is implemented as software for Windows, iOS and Android; worldwide on the internet.

Semiquantitative methods

These procedures build your score values ​​from the patient's indication of where he perceives bias. However, you cannot measure the amount of distortion.

M charts

M-Chart, schematic

M charts consist of vertical or horizontal dashed lines (see "M chart, schematic"). Each line consists of tick marks and spaces of equal length. Depending on which line (e.g. 0.4 °) no more distortions are perceived, the strengths of the distortions are classified. Evaluation and procedures are based on the examination of visual acuity .

execution

A solid line is shown to the patient. The patient fixes the point in the middle and indicates whether he can still perceive distortions. In this case, the patient is shown a dashed line and the patient fixes the point in the line (2nd line 0.2 °) and again indicates whether he is still perceiving distortions. This is repeated until the patient no longer perceives the distortion. The last line with perceived distortions corresponds to the so-called "metamorphopsia score".

execution

So far only used as a prototype in a study (as of 2018).

D charts

D-Charts uses printed maps to measure the location (angle from the center) of metamorphopsia in the visual field, creating a single score, the Total Metamorphopsia Score.

The map consists of four rings at different distances from the fixation (center point), which are divided into eight sectors. The spacing between the grid elements is between 0.4 ° and 1.8 °.

All cards consist of two octagons (octagons). The first octagon is arranged at a distance of approx. 5 cm from the center, the second at a distance of approx. 10 cm. The test was developed at Glasgow Caledonian University.

execution

The patient is asked to fix the center of the 1st map monocularly. This first card is printed with small dots around the center. The patient must now draw in the point at which he perceives distortions.

Map 2 differs from map 1 in that the dotted areas can now be found in the area of ​​the first octagon. Here, too, the areas of the perceived distortions must be drawn.

On card 3, the points are in the outer ring.

The sum of the maximum distances that are perceived as distorted in each sector gives the total metamorphopsia score.

The electronic version varies the measuring principle around the brightness of the points. The more contrasting the points, the better the patients perceive the distortion. From this fact, the program calculates a “heat map” (color map).

execution

Is available as software.

ForeSeeHome

A dotted line with a wave or bump is presented to the patient. The patient now has to click where he sees the cusp or the wave.

If no hump is presented and the patient clicks anyway, the program recognizes that the patient perceives a distortion there.

execution

Hardware by prescription in the US only.

MyVisionTrack

With the help of rings with different degrees of distortion, this test classifies how strong the central distortion is for each eye.

execution

In one measurement run, four rings are displayed on the screen. One of these rings is distorted and the patient is asked to indicate the distorted ring monocularly. In each of the passages, one ring is distorted differently. If the distortion of this ring is similar or less than the patient's central distortion, the patient can no longer tell which of the rings is distorted. The program then recognizes that the patient has to guess and can classify how strongly the central bias is perceived by the patient.

execution

Prescription software in the US only. (Status: 2018)

Qualitative process

Qualitative methods are designed in such a way that the patient indicates (draws in) where he perceives distortions. These procedures can only use the areas marked for the progress documentation. However, they do not provide a value for the strength of the distortion and the eccentricity (distance to the center).

Amsler grid

→ Main article : Amsler grid

is a map with vertical and horizontal lines on which the patient can draw the distorted lines, or whose visual impression the patient must remember. Precise instructions are important in order to perform the Amsler test correctly.

literature

• Faes, L., et al., Diagnostic accuracy of the Amsler grid and the preferential hyperacuity perimetry in the screening of patients with age-related macular degeneration: systematic review and meta-analysis. Eye (Lond), 2014. 28 (7): p. 788-96.
• Amsler, M., Quantitative and qualitative vision. Trans Ophthalmol Soc UK, 1949. 69: p. 397-410.
• Thefeld, W., Prevalence of Diabetes Mellitus in the Adult Population of Germany. Health Care, 1999. 61: p. 85-89.
• Scherbaum WA, KW, epidemiology and course of diabetes mellitus in Germany. 2004.
• Ting, DSW and GSW Tan, Telemedicine for Diabetic Retinopathy Screening. JAMA Ophthalmol, 2017. 135 (7): p. 722-723.
• Jani, PD, et al., Geographic Information Systems Mapping of Diabetic Retinopathy in an Ocular Telemedicine Network. JAMA Ophthalmol, 2017. 135 (7): p. 715-721.
• Claessens, D., Quantitative Metamorphopsia Measurement: Possibility to Improve Compliance and Adherence. Ophthalmoscope, 2017: p. 24.
• Claessens, D., Objectification and Monitoring of Visual Disturbances in Macular Diseases. Concept ophthalmology, 2018.
• Claessens, D., Schuster AK, Correlation of the quantitative metamorphopsy measurement and the central retinal thickness in diabetic macular edema and age-related exudative macular degeneration. Ophthalmic Clinical Monthly Sheets, 2018.
• Claessens, D., Krüger R., Three dimensions of quantitative metamorphopsia measurement - do disease specific patterns exist? IOVS Invest. Ophthalmol. Vis. Sci, 2017. 58 (5): p. 14th
• Arimura, E., et al., Quantification of metamorphopsia in a macular hole patient using M-CHARTS. Acta Ophthalmol Scand, 2007. 85 (1): p. 55-9.
• Chew, E., et al., Randomized trial of a home monitoring system for early detection of choroidal neovascularization home monitoring of the Eye (HOME) study. Ophthalmology, 2014. 121 (2): p. 535-44.
• McGowan, G., et al., D-CHART: A Novel Method of Measuring Metamorphopsia in Epiretinal Membrane and Macular Hole. Retina, 2016. 36 (4): p. 703-8.
• Amsler, M., Earliest symptoms of diseases of the macula. Br J Ophthalmol, 1953. 37 (9): p. 521-37.
• Amsler, M., The Investigation of Qualitative Vision with the Square Net. Instructions for using the test boards. Theodore Hamblin LTD, 1958.

Individual evidence

1. ↑ Faes, L., et al., Diagnostic accuracy of the Amsler grid and the preferential hyperacuity perimetry in the screening of patients with age-related macular degeneration: systematic review and meta-analysis. Eye (Lond), 2014. 28 (7): p. 788-96.
2. ↑ Amsler, M., Quantitative and qualitative vision. Trans Ophthalmol Soc UK, 1949. 69: p. 397-410.
3. ↑ Thefeld, W., prevalence of diabetes mellitus in the adult population of Germany. Health Care, 1999. 61: p. 85-89.
4. ↑ Scherbaum WA, KW, epidemiology and course of diabetes mellitus in Germany. 2004.
5. ↑ International Diabetes Federation  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.  
6. ^ Ting, DSW and GSW Tan, Telemedicine for Diabetic Retinopathy Screening. JAMA Ophthalmol, 2017. 135 (7): p. 722-723.
7. ^ Jani, PD, et al., Geographic Information Systems Mapping of Diabetic Retinopathy in an Ocular Telemedicine Network. JAMA Ophthalmol, 2017. 135 (7): p. 715-721.
8. ↑ Claessens, D., Quantitative Metamorphopsia Measurement: Possibility to Improve Compliance and Adherence. Ophthalmoscope, 2017: p. 24.
9. ↑ Patent: Claessens, Daniela and Krüger, Ronald: Device and method for the quantitative recording and / or monitoring of disturbances of the visual field, IPC: A61B 3/02, date of registration: August 14, 2015
10. ↑ Claessens, D., Objectification and Monitoring of Visual Disturbances in Macular Diseases. Concept ophthalmology, 2018.
11. ↑ Claessens, D., Schuster AK, Correlation of the quantitative metamorphopsy measurement and the central retinal thickness in diabetic macular edema and age-related exudative macular degeneration. Ophthalmic Clinical Monthly Sheets, 2018.
12. ↑ Claessens, D., Krüger R., Three dimensions of quantitative metamorphopsia measurement - do disease specific patterns exist? IOVS Invest. Ophthalmol. Vis. Sci, 2017. 58 (5): p. 14th
13. ↑ Arimura, E., et al., Quantification of metamorphopsia in a macular hole patient using M-CHARTS. Acta Ophthalmol Scand, 2007. 85 (1): p. 55-9.
14. ↑ Nowomiejska, K, et.al .: M-charts as a tool for quantifying metamorphopsia in age-related macular degeneration treated with the bevacizumab injections
15. ↑ IOVS, 2013: Mapping visual distortions in macular disease [1]  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.  
16. ↑ McGowan, G., et al., D-CHART: A Novel Method of Measuring Metamorphopsia in Epiretinal Membrane and Macular Hole. Retina, 2016. 36 (4): p. 703-8.
17. ↑ Chew, E., et al., Randomized trial of a home monitoring system for early detection of choroidal neovascularization home monitoring of the Eye (HOME) study. Ophthalmology, 2014. 121 (2): p. 535-44.
18. ↑ Amsler, M., Earliest symptoms of diseases of the macula. Br J Ophthalmol, 1953. 37 (9): p. 521-37.
19. ↑ Amsler, M., The investigation of qualitative vision with the square network. Instructions for using the test boards. Theodore Hamblin LTD, 1958.

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !