Case 4: 87 year old woman with shortness of breath

This movie of the patient’s CT scan shows the large goiter which starts in the lower neck and extends down into the upper mediastinum, stopping at the top of the aortic arch.  This was the cause of the patient’s symptoms.  Can you tell what other surgery the patient has had?  How can you tell that this is a CT and not an MR?  Was IV contrast given?