Thailand 17 years old male patient had been hit by a car head hit the ground. Left eye squint and double vision immediately. While in the hospital, began to urinate more frequently (10 times a day, six times a night), frequent thirst. As such, as long as three years to get treatment until symptoms disappear eyes. But urine is still very day 6-7 liters daily blood pressure 110/80 mm / Hg, urine specific gravity and osmolality of urine 1.002 ms Oswego 70 mol / kg. Serum sodium, 149 mEq / L potassium potassium4.0 mEq / l chloride 98 mEq / L bicarbonate 29 mEq / L glucose, BUN, creatinine, calcium. And phosphorus were normal neurological examination and fundus were normal. serum osmolality of 296 ms Oswego mol / kg. When patients were urinary pitressin5 units per minute, down from 9 ml per minute to 1.5 ml of urine osmolality and increased to 387 mM Oswego mol / kg.