(TUCSON, Ariz.) -- Doctors say that while the bullet that struck Arizona Rep. Gabrielle Giffords did not hit any critical parts of the brain, whether she will survive and how fully she will recover are still unknown.
"This was a devastating wound that traveled the length of the brain on the left side," Dr. Peter Rhee, trauma director at University Medical Center in Tucson, said during a press conference. Giffords' family confirmed to ABC affiliate KTRK that the bullet entered the back of her head and exited through her forehead.
Giffords is currently in a medically induced coma that doctors say will help her brain rest. She had surgery to stop the bleeding and help control swelling on the left side of the brain. Doctors also had to decompress her eyes. Eyelids often swell when there is trauma to the brain.
"Brain swelling is the biggest threat at this point," said Dr. Michael Lemole, chief of the the division of neurosurgery at the University of Arizona. To help control swelling, part of Giffords skull was removed and will be reimplanted, possibly in a few months.
Giffords was awakened periodically and she has made nonverbal responses to simple commands, but Rhee said she has not spoken because she is on a ventilator.
Lemole said Giffords was able to squeeze a doctor's hand and hold up fingers when asked, and these responses are good signs.
The next few days and weeks will be critical to determine how much brain function Giffords has lost, if any. Doctors will keep an especially close eye on the level of brain swelling and also on her ability to recover speech and movement on the right side of her body, which are controlled by the left side of the brain.
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