difference between a scan done without contrast
EAT/DRINK: If your doctor ordered a CT scan without contrast, you can eat, drink and take your prescribed medications prior to your exam. If your doctor ordered a CT scan with contrast, to your CT scan. You are encouraged to drink clear liquids. You may also take your prescribed medications prior to your exam.DIABETICS: Diabetics should eat a light breakfast or lunch three hours prior to the scan time. CT scan of the chest may also be used to evaluate the effects of treatment of thoracic tumors. Another use of chest CT is to provide guidance for biopsies and/or aspiration of tissue from the chest.