Last night, British-born actress Natasha Richardson, 45, was rushed from Montreal to New York City in critical condition after a seemingly minor fall on a Quebec ski slope apparently led to bleeding in her brain.

Richardson, who won a Tony for her role in the Broadway play Cabaret and has also starred in a string of films including The Parent Trap and Maid in Manhattan, is the daughter of actress Vanessa Redgrave and the wife of actor Liam Neeson, 56, with whom she has two sons, ages 12 and 13. She was reportedly taking a skiing lesson on a beginner slope at the Mont Tremblant resort some 80 miles (130 kilometers) northwest of Montreal when she took a spill.

"It was a normal fall," Lyne Lortie, a Mont Tremblant spokesperson told The New York Times, "She didn't show any signs of injury; she was talking and she seemed all right."

Still, her instructor summoned the ski patrol to transport her to the bottom of the hill in accordance with the resort's safety policies. Richardson reportedly refused medical care when an ambulance arrived and went back to her hotel room. About an hour later, however, Lortie said that Richardson complained of a severe headache; she was rushed by ambulance to Hôpital Sacré-Coeur in Montreal, where Neeson met her after flying in from Toronto where he was filming a movie. The actress was then flown by private jet to Lenox Hill Hospital in Manhattan, where she and Neeson have an apartment on the Upper West Side.

The family had not issued a statement at deadline and no reports on her condition had been confirmed. However, some media outlets, citing anonymous sources, claim that the actress had been on life support but was removed from it today and was not expected to survive. "It's so sad. Vanessa, her sister Lynn, everybody is gathering in New York to say goodbye," a "close friend" of the family told London's Daily Mail. "No one can believe what has happened, that this once vibrant woman, full of love, of life, is lying there brain dead."

The tragic story, if confirmed, is a reminder that even minor blows to the head can lead to devastating bleeding that can cause strokes or otherwise damage brain tissue. One possibility, sometimes called "talk and die" syndrome, is that the actress had delayed bleeding between her skull and her brain stem, which sits at the top of the spinal cord and regulates consciousness, breathing, and the heart and connects the brain to many of the body's sensory and motor nerves. Another possibility is that there was a tear in the inner lining of her arteries, causing blood clots. To find out more about Richardson's potential injury, we spoke with neurosurgeon   Keith Black, chairman of the Department of Neurosurgery at Cedars-Sinai Medical Center in Los Angeles.

[An edited transcript of the interview follows.]

Based on Richardson's symptoms, what kind of injury do you think she suffered?
The possibilities range from what we call an arterial dissection to a preexisting condition that might have been triggered by the event. An arterial dissection is where patients have a very mild injury tear the inner lining of the arteries of the neck, either the carotid or vertebral arteries, and that can occur with even minor trauma that one may not believe to be significant. That tearing in the artery can cause clotting, which can set up a stroke (an interruption of the brain's blood supply caused by a blockage or a rupture of a blood vessel). If that clot is in the vertebral artery system, it can cause a stroke in the brain stem, which can be devastating.

The other possibility is delayed bleeding in the brain. That can be from either a tear in a vein or an artery in the brain tissue itself, and that can be either an epidural hematoma (between the skull and the dura, the membrane that surrounds the brain) or a subdural hematoma (between the dura and the brain).

Another possibility is that she had a condition that predisposed her to having a more catastrophic event. This could be an abnormality in how fast her blood clots after a bleed. Or if she's been on any aspirin, blood thinners, or, supplements like omega-3 fish oil, that can make things worse.   The other thing one has to worry about is whether she had a vascular abnormality in the brain like an arteriovenous malformation (an abnormal connection between high-pressure arteries and low-pressure veins). If an AVM tears one can get a more significant bleed.   

I think the two most likely conditions would either be the arterial dissection in the neck or the delayed bleeding within the brain itself.

What is "talk and die" syndrome?
That refers to the fact that we always worry about people with head injuries that don't show up immediately, which is why we like to observe people after a head injury for 24 hours. Generally when we talk about "talk and die" it's usually a delayed bleed like an epidural hematoma.

How would you assess a patient after a fall like this?
The most important test would be a CT scan (a 3D X-ray that can provide cross-section images of anatomical structures), which would tell you if there is bleeding in the brain itself. If there is bleeding, it would tell you if it needs to be relieved with surgery or with medication. It would also give you an indication if she's had a stroke, and whether she's had one of these arterial dissections that may be showering blood clots into the brain.

How would you treat her?

If there's bleeding in the brain, if it's causing pressure and if it's an area that's accessible, one may think about surgery to remove the blood clot. Usually, that's done on an emergent basis, and since we haven't heard reports that she's going undergoing surgery then that's probably not the scenario she's facing.

Another possibility is that the clot is in an area that you cannot safely operate on like the brain stem. That's because the structures of the brain are very compact in that area, and it's very risky to operate on. One may then try to manage the clot with medications (such as hypertension drugs like labetalol).

Did the fact that she delayed treatment for an hour put her at further risk?
Obviously, when it comes to treatment—the earlier, the better. If she had gotten a CT scan right away, doctors likely would have seen the bleed. From what I understand, however, she was examined by a medic, and she was doing fine. We don't typically scan patients unless there has been a more significant type of trauma. It sounds like everything was managed appropriately and this was one of these rare catastrophic events. Even for patients that do have delayed bleeds, most of them tend to do very well, particularly younger patients. They normally don't deteriorate that fast, and one has time to stabilize the situation, control the swelling and operate to relieve the blood clot if necessary.

Is it possible that she is brain-dead?
That would be catastrophic. It's a possibility but it would be extremely rare. One would think, if that is the case there would be catastrophic injury from a stroke or a bleed in the brain stem. At Cedars–Sinai we treat hundreds of brain-injury patients, and it's very rare to see someone whose minor injury has become this life-threatening.