Detection of change in CNS involvement in neuropsychiatric SLE: a magnetization transfer study

Purpose: To assess whether magnetization transfer imaging (MTI) parameters change in correspondence with clinical changes in NPSLE patients.

Materials and methods: Nineteen female patients (mean age=37.5 years, range=19-64) underwent MTI on at least two separate occasions (mean time between scans=25.4 months, range=5.4-52.3 months). Twenty-four pairs of scans of 19 patients were available. Each patient's clinical course was classified as improved, stable, or deteriorated. Whole-brain magnetization transfer ratio (MTR) histograms were generated. The peak height of these histograms was used as an estimate of parenchymal integrity. Based on the change in clinical status, paired examinations were grouped and tested for significant differences between the first and second examinations using paired-samples t-tests.

Results: Four patients clinically deteriorated, all patients showed a significant peak height decrease (mean decrease=8.6%, P=0.02), and in 14 patients with stable disease the peak height did not change significantly (mean increase=0.4%). Six patients clinically improved, and all showed a significant relative peak height increase (mean increase=12.0%, P=0.02).

Conclusion: The peak height of whole-brain MTR histograms corresponds to changes in the clinical status of individual NPSLE patients. This suggests that MTI can be a valuable tool in the clinical assessment of such patients.