Bionic Eye - from sci-fi to reality…

Vision is a gift that we often take for granted. It allows us to appreciate the delicate intricacies and beauty around us, cherishing special moments. Now picture a world that is pitch black. Globally, 39 million people are blind.1 For decades, research has been focused on the creation of a bionic eye to help shine a light on a world of darkness. Now, this is becoming a reality.   


 Second Sight’s novel product, Argus® II, has been approved by the FDA for the treatment of retinitis pigmentosa - a rare inherited disease in which the light-sensitive retina slowly and progressively degenerates.2,3 The prosthesis involves surgically fitting an implant onto the retina, the light-sensitive area at the back of the eye. The patient wears a special pair of glasses into which a video camera has been fitted. This camera picks up the image and wirelessly sends signals to the implant, stimulating the retina and causing nerve impulse conduction to the visual cortex in the brain. Here, the brain interprets the message as patterns of light.4 This device has been authorized by Federal (U.S.) law to induce visual perception in retinitis pigmentosa and bare/no light perception.5

The system was granted regulatory approval based on an original study group of 30 patients, who are being followed-up for 10 years to establish long term efficacy and safety of the implant. So far, data up to 5-year follow-up is available, which overall has shown good reliability, safety and long- term efficacy of the implant.6

In 2018, the company also released a new implant prosthesis which is undergoing testing protocols: Orion. This system holds the potential to target many causes of blindness, including glaucoma, eye injury, diabetic retinopathy, optic nerve disease/injury and retinitis pigmentosa. However, the surgical procedure involved is more invasive, requiring an implant to sit directly on the visual cortex of the brain.7 Testing is ongoing but in the immediate short-term, the implant seems promising.

The end result is to create a perception of contrasting lights and shapes, a very basic vision but a massive breakthrough from the darkness. New developments are considering features of thermal imaging to enhance the quality of image perception. The future looks bright, and hopefully, continuing advances will one day provide the full restoration of vision!

We hope you have enjoyed this week’s post. Universal Medicine now also has 3 new writers and we look forward to welcoming their posts!

Gagandeep Sachdeva

References:
1.      https://www.who.int/blindness/publications/globaldata/en/
2.      https://www.secondsight.com/
3.      https://www.allaboutvision.com/conditions/retinapigment.htm
4.      https://www.england.nhs.uk/wp-content/uploads/2018/07/Argus-retinal-prosthesis.pdf
5.      https://www.accessdata.fda.gov/cdrh_docs/pdf11/h110002c.pdf
6.      https://www.ncbi.nlm.nih.gov/pubmed/22244176/
7.      http://investors.secondsight.com/news-releases/news-release-details/second-sight-accelerate-development-orionr-visual-cortical
Figure 1:
https://www.researchgate.net/publication/305951997_Performance_of_real-world_functional_vision_tasks_by_blind_subjects_improves_after_implantation_with_the_ArgusR_II_retinal_prosthesis_system_Functional_vision_tasks_using_ArgusR_II/figures?lo=1

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