Watching cartoons like "Sponge Bob", "Cars" and "Barbie" during radiotherapy sessions may make them less traumatic for kids as well as spare dozens of general anaesthesia doses, a study said.

According to the research, this would also make each treatment quicker and more cost effective.

There are around 215,000 new cases in the under-15 age group each year worldwide. 

Around a sixth of these children require treatment with radiotherapy, including those with brain tumours, and bone and soft tissue sarcomas such as ewing sarcoma and rhabdomyosarcoma, the researchers said.

"Radiotherapy can be very scary for children. It's a huge room full of machines and strange noises, and the worst part is that they're in the room alone during their treatment," said Catia Aguas, a radiation therapist and dosimetrist at the Cliniques Universitaires Saint Luc in Belgium. 

"Before their treatment, they have already been through a series of tests and treatments, some of them painful, so when they arrive for radiotherapy they don't really feel very safe or confident," Aguas said.

Further, apart from avoiding some of the risks inherent to general anaesthesia, the treatments that used to take one hour or more, now (while watching the cartoons) take around 15 to 20 minutes. 

This was also because the children, who know they are going to watch videos are more cooperative as they are a lot less anxious and feel more relaxed, the researchers noted, in the research presented at the ESTRO 36 conference in Vienna.

Being treated with radiotherapy means coming in for a treatment every weekday for four to six weeks. 

"The children need to remain motionless during treatment and, on the whole, that means a general anaesthesia. That in turn means they have to keep their stomach empty for six hours before the treatment," Aguas said.