Our innovative vision restoration treatments can enhance visual functions even after many years because almost all patients have some degree of vision left, called “residual vision”. Vision is not a black-and-white matter (seeing versus not seeing), but one of shades of vision, or different levels of partial vision, which need to be identified and then strengthened.
Research in the Sabel laboratory over decades has shown that the brain can, in fact, adapt rather well to vision loss when stimulated properly through a process called “neuroplasticity”. By “re-tuning” the brain to increase the activity of these “areas of residual vision”, it is possible to enhance visual processing in the brain after partial vision loss, thus activating the brain´s hidden potentials. The method we use is non-invasive low level current stimulation.
Our philosophy is to strengthen the vision potentials that are still there rather than dwelling on what was lost. And our mantra is: “abilities, not disabilities”.
Altering current stimulation is a non-invasive method to stimulate brain functions with very low currents which can hardly be felt. It can be used in patients that have suffered lesions to the retina, optic nerve or the brain. This includes diseases such as optic nerve damage, glaucoma, age-related macular degeneration, diabetic retinopathy or optic neuropathy, amblyopia and others. Lesions of the brain may be caused by stroke or brain trauma.
Brain centers communicate with each other by sending tiny electrical impulses (called “action potentials”) to each other. When two brain centers communicate often, the connection between them gets stronger. But if they are not used much, the connection gets weaker or is lost. This principle of “use it or lose it” applies to any lesion type, irrespective of where the lesion is located; in the retina, the optic nerve or deep inside the brain.
Just like muscle training increases muscle strength, the connection between the eye and brain centers that process vision (such as the visual cortex) can be strengthened by repetitive use. Whereas vision training uses small light stimuli to activate tiny regions of the retina, alternating current stimulation treatment provides electrical impulses generated by a stimulator through several electrodes which are attached to the forehead near your eyes. These electrical impulses make nerve fibers and neuronal networks fire more often and this then strengthens their connectivity of the brain´s “information highway” between eye and brain. Especially when all cells fire at the same time in a synchronized manner, which our alternating current triggers, this strengthens the connection in a lasting way (“what fires together wires together”). As a consequence, the brain centers that were less responsive to the incoming impulses (due to partial blindness), now become more sensitive again after current stimulation and start responding more easily to the natural electrical signals trying to reach the brain.
In patients suffering partial blindness the brain cannot properly process visual information or it gets to little input from the eye which then leads to so-called “visual field defects”. Since the treatment boosts the sensitivity of these partially damaged areas, “residual” brain cells become more active again and this then leads to increases in the size of the visual field and in faster reaction times.
Vision is not possible without input from the retina. However, it is the activity of brain cortical networks analyzing retinal data that results in the conscious experience of being able to see. Alternating current stimulation targets these brain networks, modifying connections between different brain regions. It is these changes that improve your vision again.
The predominant strategy of our therapies is to activate residual visual capacities within “areas of residual vision” (ARVs). Such ARVs are located at the border of the scotoma or inside of it, or even deep in the blind field. These ARVs can be observed easily by standard visual field examinations such as visual field tests with perimetry (such as a Humphrey).
These images are visual fields of both eyes taken from a patient that suffers glaucoma. Visual fields were measures before and after therapy.
White areas are areas of full vision, black areas are blind, and grey areas show regions of partial functions with a “relative” defect where vision is neither absent nor normal. We call these regions “areas of residual vision” (ARV). ARVs are typically located at the border of the blind region and here the nerve cells are neither completely damaged nor intact, but it is a region where some cells are still alive. These are the critical areas for treatment because these partially damaged regions can be restored.
An example of such improvements can be seen on this figure. Note that the left eye shows clear gains of the visual field in the lower left and right quadrant as well as some improvement in the upper right quadrant and in the center of the left eye. So after treatment the patient can detect many more light dots than before therapy. This patient also acknowledges a better reading ability, clearing of “foggy vision” and improved acuity in this left eye. This is explained by the improvement in the center of the visual field which also helped the patients read better again (watch a video about Joes treatment you may check it in youtube).
Damage of visual structures is usually not complete. Rather, some structures survives the damage. This may include areas of residual vision at the border of scotoma. But there are some more areas that may have a potential for the vision restoration. These are:
“islands of residual vision” inside the blind field;
Alternative pathways, that connect the eye and different parts of the brain. These are called “extra striate” pathways.
Noninvasive current therapy influenced the above mentioned areas as it can provoke vision-like percepts, also known as phosphenes, which trigger activity in the brain (kind of like a heart pace maker) which then leads to excitability changes in visual cortex and other brain structures. This sensitivity change improves visual functions and can explain the therapeutic effects of the treatment.
The image below shows visual field charts of another patient that suffered optic nerve trauma. Here, there is almost complete blindness in one eye with some small amount of residual vision in the lower left quadrant. After treatment with non-invasive electrical brain stimulation, marked improvements of vision were observed within this lower left quadrant, emerging from the fields of residual vision.