Mark Radon MBBCH, Abstract Co-Author: Nothing to Disclose

Jagalpathy Jagdish MBBS, Presenter: Nothing to Disclose

Mathew Kaduthodil MBBS, MRCP, Abstract Co-Author: Nothing to Disclose

Sameh Kamel Morcos MD, Abstract Co-Author: Speaker, Bracco Group Speaker, Guerbet SA Consultant, Guerbet SA Research grant, Guerbet SA Speaker, Bayer AG

To establish the diagnostic efficacy of computed tomography pulmonary angiography (CTPA) performed with low concentration (150 mg.I/ml) iodinated contrast media in pulmonary embolism.  

59 adult patients referred for CTPA were randomised to receive the low osmolar non-ionic monomer iopromide either at a high concentration(HC) of 300 mgI/ml or a low concentration (LC) of 150 mgI/ml. Patients were scanned with 64-row MDCT. Examinations were assessed blindly and independently by two experienced thoracic radiologists. Diagnostic confidence and quality of the examination were rated on an ascending scale of 1 to 4.  

3 patients had incomplete examinations. 28/30 (93%) patients in the HC group, and 18/26 (69.23%) in the LC group had good quality (quality score ≥ 3) examinations. Radiographic density in the main pulmonary arteries was 212±83 HU for the LC group, and 331±98 HU for the HC group. PE was diagnosed in 10/30 (33.3 %) in the HC group and 10 / 26 (38.4 %) in the LC group. Kappa was 0.78 (95% CI 0.54 – 1.00) in the HC group and 0.77 (0.52 – 1.00) in the LC group. Mean diagnostic confidence was 3.7 in the HC group and 3.1 in the LC group (p= 0.015). Mean quality score was 3.6 in the HC group and 2.6 in the LC group (p= 0.0001).  

Good radiographic density was possible with 150 mgI/ml CM. Although the diagnostic quality was higher in the HC group, diagnostic CTPA was achieved in 69.2% in the LC group with good agreement between observers.  

Use of low osmolar contrast media in CT pulmonary angiography to exclude pulmonary embolism would potentially be very useful in reducing the nephrotoxicity especially for patients in renal failure.

Radon, M, Jagdish, J, Kaduthodil, M, Morcos, S, The  Efficacy of a Diluted Contrast Medium at Concentration of 150mgI/ml in CT Pulmonary Angiography (CTPA) in the Diagnosis of Pulmonary Embolism.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8014343.html