Toddler's injuries unlikely to be accidental, court told

The eye injuries found in a brain-damaged 3-year-old boy were so rare that a doctor had never seen them caused accidently in 15 years, a High Court jury heard.

Dr Shuan Dai examined the right eye of Dylan Hohepa Tonga Rimoni and found it had haemorrhages on and under the surface.

Dylan died on April 18, 2008 in hospital after his life support system was switched off. An autopsy revealed he died from head trauma.

The Crown alleges his caregiver Patricia Pickering, 38, caused the injuries by slamming his head against a hard surface such as a door, wall or the floor two days before he died.

She is on trial at the High Court at Auckland, and has pleaded not guilty to murder.

Dr Dai said only in "very rare" cases was the type of injury Dylan had caused accidently.

That happened in about 1 or 2 per cent of cases compared to more than 80 per cent of cases where the injuries were caused by deliberate actions.

"In the last 15 years I have not seen one child with truly accidental trauma."

He cited a child he had examined recently who was hit in the eye with a cricket ball and had no haemorrhage.

"It's extremely rare," he told the court.

Pickering's lawyer Frank Hogan asked Dr Dai if he accepted that a child, who already had brain damage, could be further injured - and therefore have new bleeding - if, for example, they were caught by an adult as they were falling.

The doctor said he didn't believe he had the expertise to answer the question.

He was also asked about a report on diagnosis in child abuse cases that led to wrongful convictions. The children were treated in a Canadian hospital Dr Dai worked in. The doctor said he was aware of the report but not its detail. He wasn't aware of any cases that featured in the report during his time at the hospital.

The trial continues.