The laser activates the drug, which then destroys the leaky blood vessels. Since the drug is confined within the blood vessel, the laser treatment mainly targets the vessel and does not harm the overlying retinal tissue. It is thought that photodynamic therapy may offer patients with wet AMD a safer, more effective sight-saving therapy than traditional laser treatment. The cascade of biochemical reactions involved in detecting light and converting it to an electrical signal that is relayed to the brain via the optic nerve. The light sensitive cells in the retina that absorb light and convert it into an electrical signal that is passed to the brain.
Rod cells are responsible for peripheral and night vision.
Cone cells are mainly responsible for central and color vision. Proof of principle provides the first measurable evidence that an experimental therapy might also work in humans. The retina is a thin tissue at the back of the eye that contains several cell types that are similar to brain cells since they are all neurons. The photoreceptor cells of the retina absorb light and convert this light to electrical signals. The electrical signals are transferred from the photoreceptors to secondary neurons which then send the electrical signals to the visual cortex region of the brain for interpretation.