The high-profile doctor is appearing at a medical disciplinary hearing to explain how two women he operated on ended up with catastrophic brain injuries.
Dr Teo also defended allegations he acted inappropriately by slapping a patient in an attempt to rouse her in the wake of surgery, contrasting it with Will Smith's notorious slap of Chris Rock at the Oscars.
"I admit I slapped her like this (demonstrated multiple small slaps to the face) as opposed to the Will Smith type slap," Dr Teo told the hearing on Monday.
"It wakes them up and it wakes them up pretty quickly. And I will continue to do it."
Speaking prior to the Health Care Complaints Commission (HCCC) hearing, the 65-year-old said he hoped the truth would clear his name of any wrongdoing.
"Tell the truth and the truth will set you free," Dr Teo told reporters.
One of the issues under consideration by the panel of legal and medical experts is whether the women and their families were adequately informed of the risks of surgery.
Both women had terminal brain tumours and had been given in the range of weeks or months to live.
Following the surgery they were left in essentially vegetative states and died soon after.
"We were told he could give us more time. There was never any information about not coming out of it," one of the husbands was quoted in court documents as saying.
"We paid $35,000 for my wife to die. I never got to say good bye."
Dr Teo said he fully accepted the surgery he performed led to the women being "damaged", but denied the outcome was due to negligence or poor surgical technique.
"Normally what I say to patients is 'I can't promise you anything. All I can promise is to do my best. You're just going to have to trust me'."
"I always talk about death as a potential complication."
He added there is "no exact science" when it comes to tumour-brain interface.
"It was my hand, my technique, my doing that she didn't wake up. Whatever happened I take full responsibility," Dr Teo said.
Dr Teo sparred with commission counsel, Kate Richardson SC, denying accusations he unnecessarily cut across the brain midline, which had heightened risk to the patient.
"Look - we can resolve this. I did something wrong. Clearly I damaged this lady," Dr Teo said.
"The point is I made an error. A surgical error. I went too far and I damaged this lady. No one is disputing that."
In one particularly heated exchange, Judge Jennifer Boland stepped in to maintain order.
"With both of you talking over each other it doesn't help us. I appreciate that it's frustrating," Judge Boland said.
Dr Teo previously gave evidence he doesn't regret the surgeries because he believed at the time they were the best thing for the patients.
Throughout the disciplinary hearing process Dr Teo has continued to operate on patients under additional oversight imposed by the commission.
Previous hearings have drawn large crowds of supporters for Dr Teo including former Australian cricket captain Steve Waugh, and boxer Anthony Mundine.
The inquiry is scheduled to run until Wednesday.
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