Royal Society Publishing

Data Supplement

Data Supplement

Files in this Data Supplement:

  • Details on the device, study and outcome -

    The subretinal implant, clinical data and safety, function testing and statistics, patient reports and learning effects, pupillography, role of microsaccades, contributors, disclosure of interest and nine short movie clips are described in detail

    Movie 1: Electrical stimulation via the 4 x 4 direct stimulation electrode array. Orientation of the letter "U". With the patients� eyes covered, the electrodes of the DS-array were activated to form a "U" with its opening facing up, down, left or right. The patient was asked to position a cardboard "U" with the same orientation. A 25- second period was allowed between presentations for the patient to make a decision and the bioengineer to set up the pattern for the next direct stimulation. Patient 1 is shown here; the remaining movies show Patient 2.

    Movie 2: Electrical stimulation via the 4 x 4 direct stimulation electrode array. Presentation of 5 different letters. The letters I,L,O,T, and V were presented singly to the patient by sequentially activating electrodes with single pulses, using fixed voltage increments above the previously determined threshold. Pulse durations were 4 to 7 ms, with 208 ms between the activation of two electrodes. The sequence was shown only once per run. After one letter, a period up to 45 s was provided for the patient to give his answer, and for the bioengineer on the left (not shown in the movie) to set up the next letter, indicated silently by the investigator. The letters combine to the word �VOLT�, correctly named by the patient but never presented previously to him.

    Movie 3: Recognition of grating direction. Gratings consisting of thin stripes were presented on a screen about 60 cm from the patient. The patient was asked to choose one of four possible directions presented in a random, preselected order by the investigator. Due to the limited visual field provided by the chip, the patient�s field did not cover the entire screen. He usually saw only two lines at a time.

    Movie 4: Measurement of visual acuity with Landolt rings. The patient was asked to localize the gap in a Landolt "C" ring that appeared randomly in one of four different directions: top, bottom, left right. Visual acuity was calculated from the smallest Landolt C ring that was seen with 62.5% correct responses.

    Movie 5: Recognition of geometric structures. Geometric figures with an identical surface area (square, triangle, circle, rectangle, diamond) were shown to the patient, whose task was to identify each. The first two minutes of the searching process are not shown here.

    Movie 6: Objects from daily life. A table setting (saucer, spoon, knife, and cup) was presented to the patient on an illuminated black cloth. The relative positions of the objects were not told to the patient, whose task was to name and find them.

    Movie 7: Recognition and localization of unknown objects. Indiscriminately selected objects (cutlery, dishes, fruit, office supplies, etc.) were placed on a table in front of the patient, who was not told what they were. The patient was asked how many objects he/she perceived, to name and to locate them. Due to his small visual field he needed some time to first identify the number of objects and their location and to be sure that he had not overseen a possible third or fourth object.

    Movie 8: Letter recognition. A marker pen was used to write white letters on a black cardboard. The letters MIKA were written with a height of about 8 cm, and placed on the table in front of the patient. He recognized the name and identified the wrong spelling, as his name is MIIKKA, while the former Formula 1 driver H�kkinen, as mentioned by the patient, is written MIKA. Due to his small visual field he needed some time to first identify the number of letters and their location. For this task he needed about 2 minutes; the movie starts with the last minute of the searching process.

    Movie 9: Patient gazes at his hand. The patient during an experiment with unknown objects on the table suddenly discovers his hand and looks at it with visible joy, describing what he is seeing.