Double vision and slight blurred vision.

Respected doctor's My dad suddenly had double vision on last Thursday,The very next day went to opthalmologist they checked him thoroughly and took blood test.From blood sample they found the glucose level is 289rt(Taken after 50 mins after having lunch/meals @4.13PM) So opthalmologist told my dad to diabetologist and take medicine for blood sugar.The same day we explained the things to diabetologist,he adviced to take blood test next day morning.To our surprise the next day reading showed slightly elevated sugar levels (Pasting blood:125 and After Food:153).So we again went to diabetologist and showed the new report taken in the morning.He told the blood sugar levels in the morning is the correct one and told to increase walking and do few excercise.Now what we have to do?? Opthalmologist told to meet diabetologist and take medicine but diabetologist ruled out sugar from the equation and said to meet the eye doctor again!! but still my dad is having double and slight blurred vision