Okustim 2 therapy system
Okuvision

Retinitis pigmentosa is one of the diseases for which there are currently no curative therapies. This retinal degeneration leads to blindness, is genetically determined, and affects approximately one in 4,000 people worldwide, mostly middle-aged individuals. OkuStim 2 enables the first non-invasive treatment that can slow down the progression of the disease. The system consists of a headset and thread-thin electrodes and can be used at home without medical assistance. The complex technology was designed by defortec to be safe, comfortable, and easy to use. A challenge. Now the system has not only received approval as a medical device, but also won the German Design Award 2026 in gold.

The OkuStim system can slow down the progression of the disease by stimulating the retina with weak electrical impulses—emitted from fine thread electrodes placed precisely on the lower eyelid. The therapy is usually carried out by patients themselves at home once a week after a one-time medical briefing and configuration. The procedure and hardware must therefore be designed to be user-friendly, especially since most patients already have visual impairments.

Together with Okuvision, a specialist in the treatment of degenerative retinal diseases in Reutlingen, defortec analyzed and optimized the handling of the system. Finally, in an iterative process with users and the Okusvion experts, a compact headset and magnetically insertable disposable thread electrodes were developed.

One of the key challenges was integrating the electronics and power supply into the headset. Numerous trials with a focus on ergonomics ultimately led to the final design: the lightweight headset fits around the head like a headband, and the actual electrode holders are integrated additively to facilitate their precise positioning. This task is performed by the ophthalmologist, who adjusts each electrode holder along three axes using a highly precise mechanism in the holders. Patients only have to attach the electrodes and swing the electrode carriers down toward the eye using the side-mounted, haptically optimized star handles.
The headset can be cleaned by wiping it down with disinfectant, and two integrated and encapsulated spring steel hinges ensure the necessary contact pressure and adaptation to the individual head shape. Defortec also took this aspect into account and tested the headset for wearing comfort with different head shapes. Even the Shore hardness of the silicone pads over the ears and the fit of the adjustable nose bridge were clarified through testing.

New electrodes are required for each therapy session – for hygiene reasons alone. They also play a key role in handling the fine wires: stored securely in blister packs, they can be removed and inserted without contact. Thanks to magnetic fixings, the electrodes find their own fixing points; simply pulling on the orange-colored elements removes them after treatment. This ease of use was another reason for dispensing with coverings similar to VR glasses. In a sense, the mechanics have become a design feature, visualizing that this is a medical device.

defortec's services:

• Design concept

• 3D modeling

• Prototype construction for ergonomic testing

• Iterative optimization loops

• Implementation support