Children suffering from autism may now have a chance to improve thanks to a new study conducted by Dr. Dan Rossignol of the International Child Development Resources Center and colleagues from six US centers.

The study showed that hyperbaric therapy may actually improve symptoms of autism giving hopes to million is children suffering from a condition that involves impaired social interaction and communication, as well as restricted and repetitive behavior.

The finding is a success, considering the fact that starting with 1980, the number of autism cases has increased significantly. As maintained by the Centers for Disease Control and prevention, about 1 in every 150 children has autism or a related disorder. However, no one knows what causes autism. Some scientists think that some kids might be more likely to get autism because it or similar disorders run in their families. Knowing the exact cause of autism is hard because the human brain is very complicated. Some others believe that environmental factors and over-vaccinations lead to the condition.

Researchers involved in the study analyzed 62 children ages 2-7 years to assess the efficacy of hyperbaric treatment for children with autism. Hyperbaric therapy usually involves inhaling up to 100 percent oxygen at a pressure greater than 1 atmosphere in a pressurized chamber.

The children were randomly assigned to receive 40 hours of treatment over a month with 24 percent oxygen at increased atmospheric pressure (1.3 atm) or normal air in a slightly pressurized room (1.03 atm).

Children who received hyperbaric therapy were rated by doctors as "very much improved" or "much improved" compared with 8 percent of those in the control group.

Overall, 80 percent in the treatment group improved compared with 38 percent of controls.

However, Dr. Rossignol said the treatment is not a cure, but rather a technique which improves behavior, certain functions and quality of life in autistic children

"The next step is to try to find out which kids do respond, because it's an expensive treatment - it may be that kids with more inflammation respond better. It would also be nice to know how long the treatment lasts, and the findings needs to be confirmed," Dr. Rossignol added.

Treatments typically cost $120 to $150 per session and still some experts estimate that as many as 10 percent of children suffering from autism in the United States are now receiving hyperbaric therapy.

Side effects of the therapy included bruised eardrums and claustrophobia, but they were not something that cannot be dealt with.

Robert Hendren, executive director of the University of California Davis M.I.N.D. Institute, a large autism research center, said the research was "well done" but the findings need to be confirmed by others before hyperbaric oxygen therapy is recommended as an autism treatment.

The study was reported in the journal BMC Pediatrics.