My MRI says:

In the thoracic spinal canal, at the T4 and T5 levels, there is a a mild mass effect upon the posterior aspect of the thoracic cord. This pattern suggests the possibility of a posterior intradural arachnoid cyst. This picture can also be caused by anterior tethering of the cord at the level of the dural defect anteriorly.

If anyone understands what this means please let me know.Thank you.