An 18-year-old's symptoms of vomiting, headache and dizziness 10 days after a head knock while boxing were not enough to warrant a brain scan, an emergency doctor has told an inquest.
Frankston Hospital emergency physician Yigal Reuben has stood by a decision to not order a CT scan for George Diamond in the months before he died, despite desperate pleas from the teen's father.
Mr Diamond died in hospital from bleeding near his brain on February 21, 2019, with an autopsy revealing an older subdural haemorrhage from a previous head injury.
A coronial inquest is underway in Melbourne to investigate links between the head knock he suffered in October 2018, and his death after collapsing at the Sting Gym four months later.
Mr Diamond had visited two GPs with his father after being punched in the groin and head at the Cranbourne gym, in Melbourne's southeast, on October 25.
Both doctors sent him away without ordering a CT scan or MRI.
Mr Diamond's symptoms persisted and his father, Vic Diamond, took him to Frankston Hospital on November 5, concerned that he was not getting better.
"I asked Dr Reuben twice to do a CT scan, he said I was being over-protective and it was unnecessary," he told the inquest on Tuesday.
Dr Reuben said he diagnosed the young man with a concussion and provided advice about his head injury and returning to boxing, including written information.
However, he did not believe Mr Diamond's symptoms - which included vomiting that morning, back pain, dizziness and headaches - had warranted a CT scan.
"I explained to him why he needed to rest his brain and that he was not to return to sport until he was medically cleared," Dr Reuben told the Coroners Court on Wednesday.
"My assessment at that point in time was that a CAT scan was not going to alter his management on that day, it was not going to change, he was not going to require neurosurgery on that day.
"I still stand by that opinion ... he did not need a CT scan and he did not need an MRI scan. He did not meet my criteria as an emergency physician to investigate his symptoms with how he presented on that day."
Mr Diamond was medically suspended from the Sting Gym after the October concussion.
He was signed off by his GP, Pejman Hajbabaie, to return to boxing on January 25.
The inquest before state coroner John Cain continues.