The examination was aborted prior to contrast enhanced scans due to patients inability to lie flat.
Transitional anatomy, with rudimentary disc at S1/S2. The cord terminates normally at L1/2.
A large circumscribed midline mass destroys the sacrum from the level of the inferior aspect of S3, with cranial extension to entirely occupy the sacral canal to the level of S2/3. The S1 and S2 nerve roots are intact, but S3 to S5 are not distinguishable. The mass has dimensions of 7.7 x 10 x 12.7 cm (AP x transverse x craniocaudal) and bulges anteriorly to displace the rectum, but is well circumscribed with preservation of the intervening fat plane.
The mass is of heterogeneous very high T2 and intermediate to high T1 signal suggesting proteinaceous or blood products. and contains internal septae which split the tumour into incomplete lobules. No enlarged pelvic lymph nodes identified.
Vertebral body height and alignment are normal. Normal marrow signal.
There are mild endplate degenerative changes and small concentric disc bulges at L3/4, L4.5 and L5/S1, however the canal, subarticular recesses and neural foramina are adequate.
Conclusion:
Large circumscribed midline mass arising from the distal sacrum with obliteration of the S3 to S5 nerve roots. Unfortunately the mass is incompletely characterised as contrast enhanced sequences could not be performed. This mass is compatible with chordoma, and biopsy is recommended.