The role of dual energy CT in prediction of hemorrhagic complications after mechanical thrombectomy for acute Ischemic stroke

Dr Vu Thi Thanh1, Professor Pham Minh Thong1, Dr Vu Dang Luu1, Dr Tran Anh Tuan1, Dr Le Hoang Kien1, Dr Nguyen Quang Anh1, Dr Nguyen Tat Thien1, Dr Nguyen Huu An1
1 Dien Quang Center, Bach Mai Hospital

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Abstract

Purpose: Evaluate the characteristics of Dual-energy CT of the brain performed after mechanical thrombectomy. Acess the capability of iodine extravasation quantification on DECT to predict hemorrhagic complications.
Material and methods: Retrospective descriptive study. Thirty consecutive patients who underwent brain dual-energy CT right after mechanical thrombectomy for acute ischemic stroke between July 2019 and September 2020 in Radiology Center, Bach Mai hospital, were included. Maximum iodine concentration was measured. Follow-up CT or MRI examinations performed at 24hrs after intervention were reviewed for intracerebral hemorrhage development. The correlation between dualenergy
CT parameters and intracerebral hemorrhage development was analyzed by the Mann-Whitney U test and Fisher exact test. Receiver operating characteristic curves were generated for continuous variables.
Result: Nineteen of 30 patients (63.3%) developed hemorrhage in different grades. On postoperative dual-energy CT, parenchymal hyperdensities and iodine extravasation were present in 19 (100%) of the 19 patients who developed intracerebral hemorrhage and in 7 (63.6%) of the 11 patients who did not (P = 0.0012). Signs of bleeding were present in 5 (45.4%) of the 19 patients who developed intracerebral hemorrhage and in none of the patients who did not. Median density of contrast extravasation in hemorrhage and non-hemorrhage is 108.8HU and 33.6HU (P=0.001). Median maximum iodine concentration was 2.9 mg/mL in the patients who developed intracerebral hemorrhage and 0.59 mg/mL in the patients who did not (P = 0.003). Maximum iodine concentration showed an area under the curve of 0.9 for identifying patients developing intracerebral hemorrhage.
Conclusion: DECT helps differentiating haemorrhage from contrast extravasation. The presence of parenchymal hyperdensity with a maximum iodine concentration of >1.1 mg/mL may identify patients developing intracerebral hemorrhage with 94.7% sensitivity and 81.8% specificity. 

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References

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