Prosecutors sought one year in prison Monday for a doctor accused of negligence for failing to properly treat a 4-year-old boy who had gotten part of a chopstick lodged in his brain after it pierced his throat, causing him to die.

Hideki Nemoto, 37, did not conduct computed tomography or other deliberate examinations and let the family take the boy, Junzo Sugino, home after putting antiseptic on his throat injury, prosecutors said.

Sugino was eating cotton candy off a wooden chopstick on July 10, 1999, at a community summer festival in Suginami Ward, Tokyo, when he fell down. The chopstick pierced his throat and part of it broke off in his brain, they said.

He was taken by ambulance to Kyorin University Hospital in Mitaka, western Tokyo, and was examined and treated by Nemoto, who was on night duty.

The child had a decreased level of consciousness and repeatedly vomited, in what were signs of brain damage, according to the prosecutors. The boy died the following day.

Nemoto has said he did not find the chopstick during his examination and that even if he had, saving the child's life would still have been difficult.

He has pleaded not guilty to professional negligence resulting in death during his Tokyo District Court trial.