MRI of the sacral tumors(report of 29 cases) / 中华放射学杂志

ABSTRACT

Objective To explore the value of the diagnosis and differential diagnosis of the sacral tumors with MRI. Methods Twenty nine patients with histologically proven sacral tumors were viewed, including sacral chordoma( n =5), giant cell tumor( n =1), neurilemmona( n =3), ganglioneuroma( n =2), malignant lymphoma( n =4), osteosarcoma( n =1), malignant neurilemmoma ( n =1), and secondary tumors ( n =12).All patients were examined with MR,CT and plain radiograph. MR findings were analyzed. Results (1) sacral tumors involved sacral bone with a regularity. Four patients with sacral chordoma involved usually above S3 level, not including S1 bone. One patient with giant cell tumor involved S2 S3. Six patients with neuromas involved S1 S3, including S1 bone. (2) signal intensity moderate and/or low signal on T 1 weighted images, mottled signal on T 2WI. (3) sacral pores were destructed, disappeared, or enlarged. Sacral pores enlarged in six patients with neuromas, destructed in others. (4) sacral canal were destructed, disappeared, or enlarged. (5) tumors were classified into central ( n =16), centrifugal ( n =9), and mixed ( n =4) types. (6) sacral tumors were segmental on sagittal MR images. Conclusion MRI is superior to CT and plain X ray in assessing classification, segment and sacral pores and the like, so MRI is very important to the diagnosis and the differential diagnosis of the sacral tumors.