Color-Mapping of 4D-CTA for the Detection of Cranial Arteriovenous Shunts

AJNR Am J Neuroradiol. 2019 Sep;40(9):1498-1504. doi: 10.3174/ajnr.A6156. Epub 2019 Aug 8.


Background and purpose: 4D CT angiography is increasingly used in clinical practice for the assessment of different neurovascular disorders. Optimized processing of 4D-CTA is crucial for diagnostic interpretation because of the large amount of data that is generated. A color-mapping method for 4D-CTA is presented for improved and enhanced visualization of the cerebral vasculature hemodynamics. This method was applied to detect cranial AVFs.

Materials and methods: All patients who underwent both 4D-CTA and DSA in our hospital from 2011 to 2018 for the clinical suspicion of a cranial AVF or carotid cavernous fistula were retrospectively collected. Temporal information in the cerebral vasculature was visualized using a patient-specific color scale. All color-maps were evaluated by 3 observers for the presence or absence of an AVF or carotid cavernous fistula. The presence or absence of cortical venous reflux was evaluated as a secondary outcome measure.

Results: In total, 31 patients were included, 21 patients with and 10 without an AVF. Arterialization of venous structures in AVFs was accurately visualized using color-mapping. There was high sensitivity (86%-100%) and moderate-to-high specificity (70%-100%) for the detection of AVFs on color-mapping 4D-CTA, even without the availability of dynamic subtraction rendering. The diagnostic performance of the 3 observers in the detection of cortical venous reflux was variable (sensitivity, 43%-88%; specificity, 60%-80%).

Conclusions: Arterialization of venous structures can be visualized using color-mapping of 4D-CTA and proves to be accurate for the detection of cranial AVFs. This finding makes color-mapping a promising visualization technique for assessing temporal hemodynamics in 4D-CTA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Angiography, Digital Subtraction / methods
  • Arteriovenous Fistula / diagnostic imaging*
  • Carotid-Cavernous Sinus Fistula / diagnostic imaging
  • Computed Tomography Angiography / methods*
  • Female
  • Four-Dimensional Computed Tomography / methods*
  • Humans
  • Intracranial Arteriovenous Malformations / diagnostic imaging*
  • Male
  • Middle Aged
  • Retrospective Studies
  • Sensitivity and Specificity