When Dawn Balzano's 17-year-old daughter Victoria took a ball to the head during a soccer game a couple of summers ago, she felt dizzy but kept quiet about it so she could stay in the game.
The next day, she took another vicious header in a game and though she complained of feeling queasy, her coach continued to keep her on the field.
Balzano said that by the time Victoria was hit in the head yet again during a basketball game a day later, she was disoriented and having memory lapses.
"Even then the coaching staff didn't recommend a trip to the doctor, but she finally told us what was going on, so we took her to a pediatrician," Balzano said. "After two weeks of headaches, nausea and sensitivity to light, she saw a specialist who diagnosed a concussion. He ordered her to stay out of games and practice for a couple of months."
Victoria is among the million or so U.S. athletes who receive a blow to the head serious enough to cause a "concussion" injury to the brain each year, according to the American Academy of Neurology. Based on new guidelines for evaluating and managing concussions released Monday by the Academy, coaches and medical professionals will be expected to handle a case like Victoria's much differently than many have in the past.
The new guidelines call for any athlete suspected of having a concussion to be immediately removed from play and not returned until after an assessment by a licensed health care professional trained in concussion. The recommendations stress a gradual return to the game -- and only after all symptoms are gone.
"If in doubt, sit it out," said Dr. Christopher Giza, a children's neurologist at the University of California in Los Angeles and one of the lead authors of the guidelines that were published Monday in the online issue of the journal Neurology. "There is no set timeline for safe return to play."
The old guidelines, in use since 1997, grade the severity of concussion on a scale of I to III. Most experts classify a mild concussion when the athlete is confused but has full memory of the event as Grade I. Typically, the athlete is told to sit on the sidelines for a few minutes before returning to play.
Grade III concussions are characterized by loss of consciousness and memory loss for a period of time surrounding the events. Athletes diagnosed with a Grade II or III concussion are usually asked to stop play and practice for at least a week and return after being cleared by a physician.
The problem with the old guidelines, Giza said, is that they don't emphasize prevention and aren't very good at predicting how long someone might experience symptoms such as headaches, dizziness and memory deficits, which can plague someone after the initial injury.
"Sometimes an athlete who is knocked unconscious will recover quickly, while an athlete who gets what seems like a small bump on the head struggles for weeks," he said.
The new guidelines were developed by reviewing all available evidence published from 1955 through 2012. Neurologists, athletic trainers, rehabilitation medicine specialists, sports medicine experts, epidemiologists and a host of other specialty experts contributed to the final recommendations.
Dr. Anthony Alessi, chairman of the sports neurology section for the Academy said the revised guidelines call for a more individualized approach to concussion management, including prevention, diagnosis and treatment. For example, athletes high school age and younger will now be treated more conservatively than collegiate athletes and pros because, Alessi pointed out, a growing body of evidence shows they take longer to recover from concussion.
The new guidelines are endorsed by a broad range of experts and professional groups including the National Football League Players Association and National Athletic Trainers Association.
"They are reflective of the latest research and specific to the overall health and wellness of an athlete at any level, whether they play pee wee football or professional soccer," said James Thornton, president of the National Athletic Trainers Association.
Among other findings by the committee, it was noted that concussions are more prevalent when athletes play on artificial turf. Football and rugby carry the greatest risk for concussion, followed by hockey and soccer. Boxing and horse racing are also considered high-risk sports for brain injury and females are most likely to experience concussion in soccer or basketball.
Alessi said the recommendations stress the importance of having a licensed health professional trained in treating concussion at every game and practice at every level. He added that the first 10 days after a concussion appear to be the period of greatest risk for being diagnosed with another concussion.
Balzano for one applauded the new guidelines and said she hoped they would be adopted quickly by sports teams and professionals.
"Take every hit seriously and don't let anyone tell you not to worry about it," she said.
ABC Tweet Chat on Sports Concussions
At 1 p.m. ET today, Dr. Richard Besser, ABC News' chief health and medical correspondent, will host a one-hour tweet chat to discuss the new American Academy of Neurology sports concussion guidelines. For the first time ever, the nation's top neurology and concussion experts will be tweeting live from the annual conference in Minneapolis. We'll also have experts from the National Athletic Trainers Association, the Mayo Clinic, Montefiore Medical Center and other special guests.
You don't need to be a Twitter expert to follow the conversation or jump in with questions and comments of your own. To learn how you can participate, click here.