Dual energy computed tomography in differentiation of iodine contrast agent staining from secondary brain haemorrhage in patients with ischaemic stroke treated with thrombectomy

Abstract

The aim of this study was to assess the value of dual energy computed tomography (DECT) in the differentiation of iodine contrast agent staining from secondary brain haemorrhage in patients with acute ischaemic stroke treated with mechanical thrombectomy. The group analysed consisted of 66 hyperdense areas in 64 patients with acute ischaemic stroke treated with mechanical thrombectomy and controlled in DECT performed within the first 24 hours after thrombectomy. In every area both qualitative and quantitative analysis of iodine and water material density (MD) maps was performed for the differentiation of iodine and blood, as well as CT density analysis. 66.7% of hyperdense areas were classified as iodine, 18.2% as iodine + blood, and 15.1% as blood. The density of iodine was significantly higher in the iodine (median 9.64 100ug/cm3) group compared to the blood (median 3.97 100ug/cm3) and iodine + blood (median 7.57 100ug/cm3) groups. The density of water was significantly higher in the blood (median 1,051.50 mg/cm3) and iodine + blood (median 1,038.00 mg/cm3) groups compared to the iodine (median 1,021.00 mg/cm3) group. DECT with iodine-water material decomposition maps is a valuable tool in the differentiation of prolonged staining of iodine contrast agent from secondary brain haemorrhage in patients with acute ischaemic stroke treated with mechanical thrombectomy. The value of 6 100ug/cm3 (0.6 mg/cm3) seems a good threshold in quantitative differentiation of iodine from blood on iodine (water) MD maps. The value of 1,030 mg/cm3 seems a good threshold in quantitative differentiation of iodine from blood on water (iodine) MD maps.