Hello, is there any substitute test for barium enema/lower gi series in a child with chronic constipation that not involved radiation?

I get a lot of information from a simple abdominal flat plate. I can often identify the ballooning of the large bowel with this film. A gastrographin lower GI study can verify the flat plate and also provide a good initial clean out to the retained stool that is part of the problem. I hope you are working with a pedi or pedi GI experienced in this problem. It can take a year to fix when done right