SOMBA K'E/YELLOWKNIFE - The trial of a man accused of assaulting his five-month-old baby resumed in Supreme Court on Monday as two doctors gave medical evidence about injuries to the baby's brain.

A 31-year-old man is facing an aggravated assault charge in relation to an incident on Oct. 22, 2007. At the time, the man's son was five months old. The baby suffered a seizure and was rushed to Stanton Territorial Hospital, and later medevaced to Edmonton.

Dr. Gregory Butler, a doctor who specializes in diagnostic imaging, said he was called into the hospital at approximately 3 a.m. on Oct. 22, 2007 and he ordered urgent imaging of the patient's brain in relation to possible trauma.

Butler said he found evidence of fresh bleeding in the child's brain, with a hematoma or bruise on the left hemisphere, causing the brain to be pushed farther to the right.

He said he only reviewed the child's diagnostic imaging scans, and therefore never physically examined the patient.

Defence lawyer Tom Boyd asked Butler about the likelihood of the bleeding being cause by factors other than trauma, including a type of cyst and hypoxia, a condition caused by the body being denied oxygen.

Butler, testifying via video teleconference from Kentville, N.S., where he now lives, said he was trained to recognize signs of what happened, but not to determine the likelihood of one cause over another.

Dr. Vivek Mehta, also testifying via teleconferencing, but from Edmonton, Atla., said operating on the child's head was necessary because of the results of medical scans, combined with the child's unresponsive behaviour.

Mehta, an associate clinical professor with the University of Alberta's medical school, said he found blood collecting between layers of the infant's brain when he operated.

The bleeding came from torn veins in the brain, he explained.

"When there's a movement of the brain relative to the skull, theses veins can tear," said Mehta.

Boyd asked Mehta if the injuries could have been caused by the father carrying the child, tripping, and falling.

"If you fall and the head is rotating, that can cause (the veins to tear). It's plausible. Is it common? No," said Mehta.

Crown prosecutor Shannon Smallwood asked Mehta if such injuries were usually the result of blunt trauma.

"They're not usually seen in blunt trauma, in isolation ... usually this requires a degree of movement," said Mehta.

He said he did not see much in the way of other evidence the baby was shaken, but noted his concentration was strictly on the task at hand - the child's surgery.

The injured child's father said he never intended to hurt his son. He said he stumbled and fell while carrying his baby. Following the charge, the man lost custody of his two sons but he has since regained visitation. His wife, who was working outside of Yellowknife at the time of the incident, also lost custody of the two children but has since regained custody of one of them. The youngest is still in foster care.

The couple separated in order for the woman to get their child back.

There were no family members in the courtroom Monday morning. The trial continues this week.

The case was adjourned in October 2009 because one of the witnesses wasn't available until a later date. Several of the witnesses who took the stand in October testified the 31-year-old man was a loving father.