I saw damage once online that was caused by someone spraying the screen with water that then dripped downward to the connections & LED's that then (once current was applied) caused a reaction that corroded the contacts. I could see how this might look like what you're seeing depending upon what is corroded.
In any case, my first guess is that it's not fixable other than to replace the panel....and if the TV is more than a couple years old I would be inclined to have this be a replacement of the TV.
Beware the statistical correlations that only sound like they're indicative of something. Drowning deaths are tightly correlated to ice cream consumption, but this sets up no causal relationship. In fact, be wary of any statistic that is stated as if it comes with a self-evident conclusion: there is no such thing.