Arizona Rep. Gabrielle Giffords is in critical condition after being shot in the head on Saturday morning. "I am very optimistic about her recovery," said a doctor at the University Medical Center in Tucson, while acknowledging that the bullet went through her brain. In 2007, Michelle Tsai explained how one might survive a gunshot to the head. The article is reprinted below. 
 
 A sheriff's deputy in Wisconsin killed his ex-girlfriend and five others at a house party on Sunday, then fled. When he was caught hours later, he used his .40-caliber Glock pistol to commit suicide—shooting himself twice from under the chin, and then once through the right side of his head. How'd he manage to shoot himself in the head three times? 
 
 He kept missing the brain. A gunshot to the head isn't always fatal; when the gun is aimed upward from the chin, the recoil can angle the muzzle toward the face. In this case, the bullet travels through the mouth and nose instead of back into the head, where the brain lies. The victim of such a wound would suffer serious injuries to the face; he might also suffocate if the bullet hit part of his nose, or if bits of flesh block the breathing pathway. But the pain isn't necessarily excruciating; survivors say it's like being punched or kicked in the face. A victim might even remain alert enough to use his hands, or, in the case of the sheriff's deputy, to reposition his gun and try again. 
 
 The severity of a self-inflicted bullet wound to the head depends on a few factors. The larger the bullet, the more damage, since the projectile destroys any tissue in its path. Hollow-point bullets that shatter are especially dangerous, as the fragments can spread into a larger swath of brain tissue. 
 
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 But where the bullet goes is most important: the farther from the center of the brain, the greater the chance of survival. If a bullet grazes the tip of one of the lobes of the brain, the patient will probably live with proper medical treatment. If a bullet enters just one hemisphere, it's still possible to make a reasonable recovery. Someone who took a shot just to the front of the brain might suffer personality changes, like Phineas Gage, the 19th-century railroad worker who became obstinate and profane after an accident. A patient with a wound to the side of the head usually arrives at the hospital unconscious but breathing. 
 
 The gravest bullet trajectories cross from one side of the head to the other, striking the center of the brain along the way. Here lie the brain stem, the diencephalon, and other structures that together govern basic life functions such as breathing, the heart rate, blood pressure, and temperature. A bullet through the mouth, Hitler-style, can kill immediately if it strikes the brain stem. 
 
 Whatever the angle, gunshot wounds to the head are usually fatal. According to unpublished data from the University of Maryland, of 264 such victims from 2000, all but 29 died on the spot. Of the 27 who were accounted for, only 18 made it into an operating room. Eight survived with significant disabilities; 10 had a good recovery. 
 
 Got a question about today's news? Ask the Explainer . 
 
 Explainer thanks Bizhan Aarabi of the University of Maryland Medical Center, Robert Levine of the University of Texas School of Medicine at Houston, and Dave Ross of Penrose Hospital in Colorado Springs, Colo. 
 
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 Like This Story ||||| Arizona Rep. Gabrielle Giffords remains in intensive care following surgery at the University of Arizona Hospital for a gunshot wound to the head at close range. 
 
 Dr. Manny Alvarez, senior managing health editor of FoxNews.com, said surviving a gunshot wound to the head is rare, but not unheard of – and Giffords is in for a long fight. 
 
 Alvarez said the survival rate of a gunshot wound to the head is about 5 percent – and 3 percent of those who do survive will always have a neurological deficiency, such as memory loss or a lack or motor skills. 
 
 “It all depends on where the bullet goes,” he said. “Your best chance of survival is from front to back, if you get shot side to side, the survival rate is less, and it all depends on the damage the brain has.” 
 
 Giffords’ friend, state Sen. Linda Lopez, confirmed the bullet entered Giffords’ head at her temple and exited through her forehead. Lopez said Giffords was responding to commands before surgery but is not sure what Giffords' long-term prognosis is. 
 
 “If the bullet goes through both hemispheres and leans toward the base of skull, that is where most of the vascular tissues are, and that can be a deadly result,” Alvarez said. “If the bullet goes through both hemispheres, but there is a clean exit wound, the patient can be lucky and there might not be any significant damage. Of course, the best prognosis is when the bullet affects only one hemisphere. Nonetheless, any gunshot wound to the head is going to leave residual side effects.” 
 
 Alvarez said the next three to four days is considered the most critical for Giffords, and recovery could take years to achieve. 
 
 “Doctors carefully opened the skull and looked for any type of bleeding and then cauterized blood vessels,” Alvarez said. “Patients are kept under anesthesia for three to four days to monitor brain swelling, which is one of the complications of this surgery." 
 
 Alvarez pointed to the story of a British soldier who survived a gunshot wound to the brain but learned to walk and talk again and in October 2010 was quoted in the The Sun as saying, “They say I’m a walking miracle.” 
 
 The soldier, Liam Brentley, was shot near the ear, and the bullet came out the other side of his head, pinging a wall, according to the U.K. newspaper. 
 
 Brentley is deaf in one ear and has some memory loss.
– The survival rate of a gunshot wound to the head, as Arizona Rep Gabrielle Giffords suffered yesterday, is about 5%, and 3% of those who do survive carry lasting neurological deficiencies, such as loss of memory loss or motor skills, reports Fox News. The next three to four days are most critical, says a Fox News doctor. Doctors first open the skull, look for bleeding, and cauterize blood vessels. "Patients are kept under anesthesia for three to four days to monitor brain swelling, which is one of the complications of this surgery," explains the expert. If the bullet grazes the tip of one of the brain lobes, the victim has the greatest chance for survival, and a bullet through one hemisphere still offers a reasonable chance. "[T]he farther from the center of the brain, the greater the chance of survival," reported Slate in a 2007 article about a slaying in Wisconsin. "The gravest bullet trajectories cross from one side of the head to the other, striking the center of the brain along the way." Doctors said yesterday they were "optimistic" about Giffords' chances for recovery.