Time-to-Maximum of the Tissue Residue Function Improves Diagnostic Performance for Detecting Distal Vessel Occlusions...

Area of Science:

• Neuroradiology
• Medical Imaging
• Stroke Diagnostics

Background:

• Detecting intracranial distal arterial occlusions using CT angiography (CTA) presents diagnostic challenges.
• Accurate identification is crucial for timely clinical decision-making in acute ischemic stroke.

Purpose of the Study:

• To evaluate if CTP-derived time-to-maximum (Tmax) maps enhance diagnostic performance in detecting distal intracranial arterial occlusions on CTA.
• To assess the impact of Tmax maps on reader confidence and interpretation time.

Main Methods:

• A retrospective study included 70 patients with distal arterial occlusion and 70 controls undergoing multimodal CT (CTA and CTP).
• Four readers independently interpreted CTAs with and without Tmax maps, assessing occlusion presence, confidence, and time.
• Diagnostic accuracy was evaluated using ROC analysis; confidence and time were analyzed with the Wilcoxon signed rank test.

Main Results:

• Sensitivity for detecting occlusions on CTA increased from 70.7% to 90.4% with Tmax map use.
• Diagnostic accuracy significantly improved for all readers (P < .001), with AUC increases ranging from 0.114 to 0.186.
• Reader diagnostic confidence and interpretation speed also showed significant improvement.

Conclusions:

• The use of CTP-derived Tmax maps demonstrably improves diagnostic performance metrics for detecting distal arterial occlusions on CTA.
• Tmax maps are valuable tools for aiding CTA interpretation in acute stroke imaging protocols for all levels of reader experience.
• Integrating CTP into acute stroke imaging protocols offers added diagnostic value.