The aim of our study is to investigate the opacification of renal vasculature, radiation dose, and reader confidence by a patient-tailored contrast administration protocol during renal CTA. IRB approved hybrid retrospective and prospective study was performed on 200 consecutive patients undergoing renal CTA. Patients were recruited into one of two protocols. 100 of which were assigned retrospectively to protocol A and the other 100 were allocated prospectively to protocol B. Both protocols implemented a contrast material and saline flow rate of 4.5 mL/sec. Protocol A utilized a 100 mL of intravenous contrast material (Optiray 350 mgI/mL) while protocol B employed a patient-tailored contrast media formula (Visipaque 320 mgI/mL).  Attenuation profiles and contrast-to-noise ratio (CNR) of the renal arteries and veins were measured. Effective dose was calculated. Comparison of data was done using independent sample t-test. Receiver operating characteristic (ROC) and visual grading characteristic analyses were performed.     

Two hundred consecutive rCTA were evaluated from July 2012 to September 2015. One hundred consecutive patients with suspected renovascular disease between July 2012 and June 2014, underwent the conventional CTA contrast protocol (protocol A). On the other hand, one hundred consecutive patients underwent the patient-tailored contrast material injection protocol (protocol B) between July 2014 and September 2015.  

IRB approved hybrid retrospective and prospective study was performed on 200 consecutive patients undergoing renal CTA. Patients were recruited into one of two protocols. 100 of which were assigned retrospectively to protocol A and the other 100 were allocated prospectively to protocol B. Both protocols implemented a contrast material and saline flow rate of 4.5 mL/sec. Protocol A utilized a 100 mL of intravenous contrast material (Optiray 350 mgI/mL) while protocol B employed a patient-tailored contrast media formula (Visipaque 320 mgI/mL).  Attenuation profiles and contrast-to-noise ratio (CNR) of the renal arteries and veins were measured. Effective dose was calculated. Comparison of data was done using independent sample t-test. Receiver operating characteristic (ROC) and visual grading characteristic analyses were performed.