Does Reduction in Contrast Administration Dose in Computed Tomography Arteriograms Degrade Image Quality? A Single Institutional Review of an Ultra-low Contrast Dose Protocol
Does Reduction in Contrast Administration Dose in Computed Tomography Arteriograms Degrade Image Quality? A Single Institutional Review of an Ultra-low Contrast Dose Protocol
The purpose of the study is to determine if the dose of contrast (Omnipaque) administered for Computed Tomography Arteriograms (CTA) can be reduced without degradation of image quality. The hypothesis is that there is no difference in image quality using ultra-low dose contrast in CTA exams compared to routine, standard of care dose exams.
Any adult patient age 18 and above, scheduled for routine CTA (Computed Tomography Arteriograms) of the chest or chest, abdomen and pelvis meeting inclusion criteria and not meeting any exclusion criteria will be included in the study. The patient will be administered a low dose of intravenous contrast based on the study examination as described below.
CTA of the chest: 40 mL of intravenous contrast (Omnipaque) at a rate of 5mL/sec. A region of interest (ROI) to trigger the scan will be placed in the aortic arch. If scan is performed using high pitch helical mode, the scan delay will be increased by 2 seconds.
CTA of the chest and abdomen or CTA of the chest, abdomen and pelvis: 50 mL of intravenous contrast (Omnipaque) at a rate 5mL/sec. A region of interest (ROI) to trigger the scan will be placed in the aortic arch. If scan is performed using high pitch helical mode, the scan delay will be increased by 2 seconds.
Following the examination, the primary investigator (PI) or team members will evaluate the images obtained with low contrast dose and each patient's prior CTA examination performed with routine contrast dose, 100mL at a rate of 4mL/sec. This will be done by quantitative and qualitative measures. For the quantitative portion, the PI or team members will place regions of interest on predetermined arterial locations to obtain measure the degree of opacification. For qualitative measurement, the images will be presented in a blind fashion to two thoracic trained board certified radiologists and a board certified interventional radiologist to determine the quality of the images based on a Likert numerical scale. Qualitative and quantitative data for the images obtained with low contrast dose and those for the prior CTA examinations performed with routine contrast dose will be compared. This data along with details of the scan protocol (dose, dose rate, scanning parameters etc.) and demographic data (such as sex, age and BMI at the time of examination) will be recorded.
Inclusion Criteria:
Exclusion Criteria: