I'm not a doctor, nor do I pretend to have any particular insight into this
question, but I have to say I'm skeptical about all of the references to
"pressure" and related physical effects. Depending on what type of aircraft you
are flying in, the takeoff roll will take anywhere from 30sec to a minute, to
attain a speed of 120-130Kt or so. That's a slower acceleration than your own
car starting out at a red light. Atmospheric pressure differential at takeoff
is about the same as going up the stairs in your own house. There may indeed be
a moment of disorientation as you leave the ground, as our sneses are not
"programmed" to understand this event, but the purely physical penomena at the
moment of takeoff in an airliner are simply not very extreme, compared with
everyday events, such as walking and driving.

What do you mean when you say you "cannot see straight"? Do you see blackness?
Do you see distorted images? Tunnel vision? What visual disturbances do you
perceive?

Do you have headaches? You complain of sinus problems - has any doctor ever
suggested you may have a migrane condition?

Otherwise, even though you say you are comfortable flying, one is strongly
tempted to suspect this is a panic response, and the symptoms are
psycho-somatic.

G Faris