Could near complete effacement of the thecal sac cause neuro problems with eyes, dizziness and nausea. i also have a gross swelling of right hand.?

Probably unrelated: The thecal sac is what surrounds the spinal cord and contains spinal fluid. Effacement just means that there is no fluid in the space around the spinal cord. This can be from pressure inside the cord, outside the cord, or a non-specific normal variant. You need to discuss this with your doctor and get a thorough neurological evaluation.