Hi, thanks for using healthcare magic
EDG stands for esophagogastroduodenoscopy
. It looks at the lining of the esophagus
, stomach and the duodenum
( the first part of the intestines).
A ct scan
can be done to look at various points of the body such as the head, chest, abdomen,pelvis.
With a history of nausea, it is likely that CT suggested may be an abdominal CT.
The EDG would have only given information on the inside of the esophagus, stomach and duodenum. Since this was reportedly normal, your doctor may want the CT to see the other structures in the abdomen.
I hope this helps