Preop MRI Screening for Adolescent Idiopathic Scoliosis May Not Be Necessary

Most patients with scoliosis developing after the age of 10 do not need routine magnetic resonance imaging (MRI) scanning before spine-straightening surgery, suggests new research.

The study's findings were published in the April 14, 2011, issue of the journal Spine. In young scoliosis patients without symptoms of neurologic abnormalities, preoperative MRI scanning adds costs while detecting few abnormalities and adding little data for surgical planning, according to research led by Dr. Mohammad Diab, from the University of California San Francisco (UCSF; USA).

The researchers analyzed data on 2,206 patients with adolescent idiopathic scoliosis, gathered from a larger study of scoliosis surgery in children. Adolescent idiopathic scoliosis is the most common type of scoliosis, generally developing after age ten. These children have no identifiable cause of their spinal curvature. The patients were 1,812 girls and 394 boys; average age at scoliosis surgery was 14 years, 3 months.

Forty-two percent of the patients underwent MRI scanning before surgery. Preoperative MRI is at times recommended to look for accompanying conditions that may affect the surgical plan--especially neurologic disorders causing damage to the spinal cord itself. None of the children in the study had any indications of neurologic problems before surgery.

The MRI scans detected other abnormalities in about 10% of children screened, or approximately 4% overall. The most common abnormalities were congenital malformations (syringes and Chiari malformations) with the potential to cause spinal cord damage. Patients with these neurologic abnormalities need neurosurgery, in addition to straightening of the spinal curve.

Two factors--more severe curvature of the middle spine and juvenile scoliosis (developing before age ten)--were correlated with a higher rate of MRI abnormalities. These factors might be helpful in identifying which children should undergo preoperative MRI scanning. There were no differences in complication rates between patients with normal versus abnormal MRI scans.

The study provides spinal surgeons with new guidance on using MRI for preoperative evaluation of patients with adolescent idiopathic scoliosis. The results suggest that MRI is currently over-requested--it is performed in a relatively high number of patients, most of whom have no abnormality. In this situation, performing MRI not only adds unnecessary costs, but may potentially lead to increased risks.

Although the study may invite debate among surgeons, Dr. Diab and coauthors believe that most patients with adolescent idiopathic scoliosis--as long as they have no symptoms indicating neurologic abnormalities-do not need MRI scanning before surgery. They concluded, "Our data question the routine use of MRI as a screening tool for adolescent idiopathic scoliosis."

Related Links:
University of California San Francisco