Hamad Hospital has a one, you can get an appointment easily enough if you go to the evening clinic. I think its on the 4th floor of the out patients dept.

Also Al Ahli hospital has a Specialist that come every 2 weeks from Dubai. You would need to go there to make an appointment.

Just take complete medical records with you, I find the doctors here are to quick to prescribe glasses to infants and small children when they may not be needed.