A UK-based neuropathologist has told the Circuit Criminal Court she no longer believes there is scientific validation to support what is known as shaken baby syndrome.
Dr Waney Squier was giving evidence in the trial of 34-year-old childminder Sandra Higgins of The Beeches, Drumgola Wood, Cavan town.
Ms Higgins denies causing serious harm to a ten-month-old baby at her home on 28 March, 2012.
Closing arguments in the case will be heard tomorrow.
Dr Squier, who gave evidence for the defence, said that 15 years ago she began to question the diagnoses of suspected shaken baby syndrome and now does not agree it is a syndrome with any scientific validation.
She said CT and MRI scans of the baby in this case supported a suggestion of impact to the head or a prior injury.
She said this was more likely the cause of the baby's injury than shaking.
She said the bleeding on the brain could have been several weeks old and could also have been a re-bleed or reactivation of a prior injury caused by trauma or spontaneously.
Dr Squier also said she did not believe it was possible to time the baby's injury because there were bruises of varying ages found on her.
She also said it was possible for a baby to appear well for some time after a head injury before showing catastrophic symptoms.
She said studies had established the possibility of a "lucid interval" in babies following a head injury although not very common.
Dr Squier said it would be dangerous to say the injury took place immediately before the onset of symptoms.
During cross-examination by counsel for the prosecution, she accepted that her job as a pathologist involved examining tissue and not treating sick children.
She also agreed it would not be advisable to reach conclusions without a multi-disciplinary approach.
She denied having "a deep seated conviction or fixed belief" about shaken baby syndrome.
She said after 15 years of research, many of the elements of syndrome had been overturned by research.
She believed the so-called "triad of symptoms" including brain injury, brain bleed and retinal bleeding was no longer reliable.
"We cannot be sure these symptoms can be caused by shaking or only by shaking," she said.
Prosecuting counsel Sean Gillane said she was relying on the reports of US pathologist Julie Mack for her evidence and that Dr Julie Mack shared her view on shaken baby syndrome which was contrary to the standard view of the vast majority of medical professionals.
Mr Gillane asked if she was seriously contending that the multiple injuries found on the baby were consistent with accidental.
She replied: "They are absolutely consistent with accident.
"What we have to do is tease out and be careful about how we deal with these injuries because we have evidence of multiple different timings (of injuries)."
However, she also agreed the injuries could be consistent with inflicted trauma.
A garda handwriting expert earlier told the court that several different pens were used in a diary kept by the childminder.
Detective Garda John Leonard inspected the notebook used by Ms Higgins to record the feeding and sleeping times of the baby amid allegations by the prosecution that some entries had been altered or written in after 28 March 2012.
He said he could establish that a change had been made to the nap time of the baby on 28 March but he could not establish what the original entry had been.
He accepted in cross-examination that more than 20 alterations had been made to entries which were obvious and visible to the naked eye and that different pens were used throughout the diary.
Defence Counsel Remy Farrell pointed out that some of the alterations were very minor such as the temperature of the baby to the number after the decimal point.
The evidence in the case has now concluded.
The jury will hear closing arguments tomorrow.