hi
I agree with your doctor.An MRI is a must to asess the cause of
scoliosis more so having developed now at this age which may be secondary to musculo-ligamentous inflammatory condition of spinal muscles or some condition of paraspinal muscle,ilio-psoas spasm due to
vertebral attachment of ligaments/tendons inflammation or infection abscess of vertebrae etc.The scoliosis may be secondary flexible tilting of spine by pull push by inflamed group of spinal/paraspinal musculature.MRI shall givr position of muscles,ligaments,vertbral joint,
disc disease etc which may be causing compensatory shifting to either sideby drag or push.
The doctor shall asess your other abdominal organs like kidney,bowels etc in addition ,for inflammation,adhesions,banding with diffuse
fibrosis near the spine
I believe finding the cause shall make it treatable.You may be asked for fever,urinary and bowel symptoms also if any, h/o
acute abdomen etc
So you may subject youself for further tests and evaluation, MRI etc for manageable condition