The brain cannot adapt if there are severe eye floaters that literally block the optical pathway
Most ophthalmologists apply a one-size-fits-all, dogmatic approach to floater treatment, or the lack of it, based on the evident misconception that all people experience floaters in the same way. That is patently wrong. Vision can be obscured by large floaters. The brain cannot "adapt" to fill in a portion of an image the retina cannot see. This happened to me.
I experienced PVD and severe vitreous syneresis in both eyes. By severe, I mean my vision was significantly blocked by large, aggregated floater masses--not tiny dots, wisps and threads, but large, entwined masses. Some ophthalmologists told me the condition was benign, and therefore not treatable, because my retinas were healthy.
Those ophthalmologists ignored the fact that I literally could not see through the floater masses, which obscured about 90% of my field of view in one eye and about 50% in the other. By obscured, I mean the field of view was blackened out. Not dimmed. Not fuzzy. Blackened out.
Three ophthalmologists (one a retinal surgeon) finally agreed that the health of my retinas was not the issue, my ability to see using those retinas was the issue. After pars plana vitrectomy in both eyes, I could see again. During follow-up to those procedures, the surgeon noticed I had a thickening epithelial membrane on one retina that was deforming the fundus through traction.
That means those ophthalmologists who said I should live with floaters because I had healthy retinas were wrong. I couldn't tell my vision was distorted because I could not functionally see through the floaters that blocked the center of the field of view in that eye. A third surgery was required to conduct a retinal peel. The macular pucker was arrested, and subsequently the vision distortion partially reversed itself.
Similarly, floaters smaller than those I experienced, such as Weiss rings, can produce persistent blockages in the field of view that are not insignificant because of their shape or location. They are big enough to be a persistent problem--not annoyance, but problem. I am familiar with floater-afflicted musicians.
When performing while sight-reading music, they cannot discern notes from a score quickly enough. This gets right to the heart of the issue of whether the brain can "adapt" to floaters. Ophthalmologists gave me static vision tests with unlimited time to discern the samples. I was actively encouraged to take my time and figure it out.
Of course, with enough time, I could always figure out what the images were by looking through transient (less than a second) gaps in the floater masses or looking off axis through the edges of my field of view that were not blocked. Not once was the difficulty encountered, or time consumed, in my figuring out the images recorded or assessed.
Consequently, I was deemed as being able to see just fine. However, the world does not work in the way those poorly designed and executed tests suggest. Tiny floaters can be ignored by the brain--I know because I still have some dots and threads inside my eyes.
However, large floaters lead to quality of life issues--including the inability to adequately function day to day--that some ophthalmologists are too quick to dismiss as unimportant, owing to outdated dogma that ignores recent advances in surgical devices, techniques and medications.
I Also Agree But.....
I agree that many ophthalmologists dismiss floaters too easily and do not understand that large dense floaters can cause visual obstruction similar to organic eye diseases.
However, it is a known fact that there are definite risks involved with vitrectomy, most notably accelerated cataract formation. My eye doctor told me that I would be in need of cataract surgery within one year of vitrectomy. This would then involve another risk subset and uncertain results.
This floater problem is really a catch 22 situation. You can either deal with the problems you have or choose to invite in a different set of likely problems.