in the macula in a few minutes
– by an uncomplicated
macular degeneration test
The examination at 33 places in the central visual field takes about 3 minutes.
After completion of two complete measurements (at 100% and 10% contrast), the test report can be saved and/or printed.
Installing the MMT software and the test setup
Before starting to use the MMT2.0, the size of the “wagon wheel” display needs to be calibrated. To do this, click on the “Calibration” button, then use a ruler to measure the diameter of the display area and enter this value in cm.
Please place the screen in such a way that no reflections are caused by interfering light sources. All measurements are taken in daylight (photopic lighting conditions) and with maximum screen brightness.
You can specify your company or office address on the test report. To do this, click the “office address” button and enter the address.
The measuring process:
How the test is conducted.
The measurement is quite simple:
the client is sitting as comfortably as possible and views the screen at a distance of 40 cm. The head can be stabilized by a chin rest to better control the viewing distance. During the measurement, a stimulus, e.g. a letter, is briefly displayed in a location that cannot be predicted by the client. The client’s task is to recognize the stimulus and to communicate it to the examiner. The type of the stimulus can be pre-selected in the test settings: single letters or Landolt rings. The examiner enters the answer on the keyboard, which triggers the appearance of the next stimulus.
Instructions to the subject
Maximum accuracy of the test results can be ensured if the clients are able to keep their gaze as stable as possible during the test procedure.
Since people with a loss of foveal vision often have unstable fixation, they need specific instructions from the examiner to control and stabilize their gaze. The following procedure has proved to be helpful:
The examiner asks: “Do you have any idea where the center of the circular display area (the “wagon wheel”) is?”
Usually, the patient answers this question with „Yes“.
“Please direct your gaze at this center and keep it there as stable as possible.”
Example of a test report
A report in detail (example):
The measurement report shows the result of the 100% contrast measurement (top) as the measurement with reduced contrast (10%, bottom). A white square is marked in the report on the visual field where a letter has been correctly identified. In places where the client had no perception, a black square is drawn. Half-filled squares indicate places where perception was possible, but a letter was recognized wrong. In this example, the client has a total score of 30.5 of max. 36 score points. Repeated measurement under reduced contrast conditions resulted in a score of 19/36 score points. To evaluate the result, the so-called general field score ratio (GFS ratio) is calculated: GFS ratio = 10% score / 100% score. In this example, the GFS ratio is 19 / 30.5 = 0.62. This means that the client has only reached 62% of its maximum performance (under 100% contrast) by reducing the contrast.
The GFS ratio shows a dependency on age and is shown together with the age of the client in the adjacent coordinate system. In addition, the coordinate system shows the course of an age curve. Our client is clearly below the age curve. Losses from the y value = 1.0 to the black age line can be explained by the age, further losses cannot be explained with the age alone. That means, if the blue result point is shown under the age line, the client is considered as conspicuous. This does not automatically mean that he is suffering from an AMD etc.. Further reasons for losses can be found, e.g. also cataract or other retinal diseases. Clients who become conspicuous in this measurement program should be advised for more clarification to an ophthalmologist.