MR whole spine projection: Computer-based simulation of conventional scoliosis projection.

Purpose: Development of an MR-based imaging technique for the spine allowin g reduction of frequency of conventional Nadiographs in the monitoring of j uvenile scoliosis. Patients and Methods: 25 patients between the ages of 6 to 36 years were examined in supine position. Two examinations of the cervi cal and upper thoracic spine and of the lower thoracic and lumbar spine wer e performed with a 1.5 T Gyroscan ACS-NT Powertrak 6000 system with body co il employing 3D EPI-sequence (T-R 17 ms, T-E 9 ms, flip angle 20 degrees, f ield of view 450 mm) or 3D FFE-sequences (T-R 9 ms, T-E 4.5 ms, flip angle 20 degrees, field of view 450 mm) and pulse-oxymetry gating. 64 coronal sli ces were acquired with reconstructed slice thickness of 2 mm. Image process ing was performed with an algorithm merging acquisition results into two si ngle images in the coronal and sagittal orientations allowing measurement o f the Cobb angle. Results: Mean examination time was 14 minutes per patient . Mean data processing time was seven minutes. Interobserver variance of de termination of the Cobb angle was 1.8 degrees. Conclusions: It is to be hop ed that MR whole spine projection will allow a reduction of the frequency o f conventional projection in the monitoring of juvenile scoliosis.