Dual energy CT after stroke thrombectomy alters assessment of hemorrhagic complications

Area of Science:

• Radiology
• Neuroimaging
• Stroke Imaging

Background:

• Intracranial hemorrhage (ICH) is a critical complication following endovascular thrombectomy (EVT) for acute ischemic stroke.
• Accurate detection and grading of ICH are essential for patient management, including monitoring, secondary prevention, and prognostication.
• Plain noncontrast CT (pCT) is the standard for initial ICH assessment, but its accuracy can be limited in subtle cases.

Purpose of the Study:

• To evaluate if combined dual-energy CT (cDECT) improves the diagnosis and classification of ICH after EVT compared to pCT alone.
• To assess the impact of cDECT on radiologic reporting and interreader agreement for post-EVT ICH.

Main Methods:

• A retrospective analysis of 372 patients who underwent DECT scans within 36 hours after EVT between 2012 and 2016.
• Two readers independently evaluated pCT images and subsequently cDECT images (including water-weighted and iodine-weighted images) for ICH diagnosis and grading using Heidelberg and SITS-MOST classifications.

Main Results:

• cDECT changed ICH diagnosis to contrast staining in 34% of cases and modified ICH grade in 10%.
• Initially undetected ICH was diagnosed in 2% of cases with cDECT.
• cDECT demonstrated higher sensitivity (95%), specificity (80%), and accuracy (85%) for ICH detection compared to pCT alone, with improved interreader agreement (Cohen κ = 0.77 vs 0.68).

Conclusions:

• cDECT significantly alters the radiologic report for post-EVT ICH in a substantial proportion of patients compared to pCT.
• These changes have potential implications for clinical decision-making regarding patient monitoring, secondary prevention strategies, and prognostication.
• cDECT enhances the consistency and accuracy of interpreting high-attenuating changes on post-EVT images, potentially improving diagnostic confidence.