What Does This CT Scan Finding Indicate?

What does this mean? "Near complete T2 intensification present in the left sphenoid air cells representing a mucous retention cyst or polyp." It was the diagnosis of a CT scan of my head from October. I had a head injury the other day and my new CT scan of the head shows a cyst 23 mm in size and am being referred to an ENT. I am waiting on that appt. In the mean time I am having AWFUL headaches, vomiting, nausea, vision problems, left eye drooping still, unsteady on my feet still. Does this mean I had a cyst and it had grown that fast? And what does this mean for me? I am 42 years old and have had chronic sinusitis problems.