Bianchi suffered the severe head injury in an incident at the Japanese Grand Prix on Sunday when the Marussia driver collided with a recovery vehicle that was attending to Adrian Sutil's earlier crash.
The Frenchman underwent emergency surgery after being transported to hospital in a reportedly unconscious state, with his condition since described as "critical but stable".
A statement from Bianchi's family, released on Tuesday via Marussia, confirmed he has a "diffuse axonal injury".
And consultant neurologist Dr Pankaj Sharma, who works at Imperial College London, has told Omnisport of the grave seriousness of such injuries.
"A diffuse axonal injury occurs following a severe head injury," he said. "Usually that head injury is a consequence of a road traffic accident.
"What it means is the brain continues to accelerate when the skull has stopped accelerating and what happens is the connections between the nerve cells have ripped.
"It's a bit like a highway linking various cities. The cities are fine but the highways have all broken up as the acceleration has ripped the highways between the cities.
"Diffuse axonal injury has a very poor prognosis unfortunately. Clearly it's difficult to determine his particular prognosis at such an early stage.
"Unquestionably he is receiving the best medical care and so his prognosis hopefully will be better than the majority of people who have this.
"The outcome is often very bad. Usually patients may not recover consciousness. The fact that we know about it, can diagnose it and we know how to treat it is helpful but nevertheless if someone does suffer it, it has a poor outcome."
Dr Sharma went on to describe Bianchi's accident as "unusual" in the "very safe" sport of Formula One, adding that it is too soon to predict how the 25-year-old will recover.
"It is a dangerous sport and it is surprising more accidents have not occurred and the fact that more accidents have not occurred suggests that the medical staff and safety staff at F1 have done their job extremely well," he continued.
"You never get a zero per cent accident rate but clearly it is a dangerous sport and no doubt accidents do occur and will continue to occur but hopefully extremely rarely.
"It's way too early to tell what the outcome will be and whether he will be able to return to the sport. Clearly it's a very significant head injury and I guess he's not going to be returning for some considerable period of time."