Abstract: PO1338
Geometry and Interuser Variability of Arteriovenous Fistulas in Mice and Rats
Session Information
- Vascular Access
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Dialysis
- 704 Dialysis: Vascular Access
Authors
- Northrup, Hannah M., University of Utah, Salt Lake City, Utah, United States
- Falzon, Isabelle Dorothy, University of Utah, Salt Lake City, Utah, United States
- Cahoon, Savanna, University of Utah, Salt Lake City, Utah, United States
- Shiu, Yan-Ting Elizabeth, University of Utah, Salt Lake City, Utah, United States
- Somarathna, Maheshika Srimali, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Lee, Timmy C., University of Alabama at Birmingham, Birmingham, Alabama, United States
Background
Arteriovenous fistula (AVF) maturation failure is a significant and unresolved clinical issue. Although rodent models have been used extensively to investigate the pathobiology and treatment of AVF maturation failure, the literature has largely relied on histology to analyze rodent AVF remodeling. Information regarding three-dimensional (3D) AVF lumen geometry in live animals is lacking. Our group has developed a magnetic resonance imaging (MRI)-based protocol to quantitively characterize 3D AVF lumen geometry in mouse and rat AVFs. Inter-user variabilities were also determined.
Methods
Carotid-jugular AVFs were created in C57BL/6 mice (n=21). Femoral AVFs were created in Sprague Dawley rats (n=7). Both had the arterial-side-to-venous-end configuration. Black blood MRIs were taken at 7 or 21 days post-AVF creation. Two users reconstructed the AVF lumens and computed the cross-sectional lumen area, anastomosis angle, nonplanarity angle magnitude, and tortuosity, using a centerline-based approach.
Results
Mice had a greater anastomosis angle (94.29° vs. 38.75°) and tortuosity (0.42 vs. 0.035) than rats (p<0.05). The nonplanarity angle magnitude was similar for mice and rats (~8.5°). Geometries of mouse and rat AVFs from the two users are overlaid in Figure 1. Inter-user variabilities were predominately small, indicating the reliability and reproducibility of our protocol.
Conclusion
Our work is the first detailed study of luminal changes in rodent AVFs using MRI. The anastomosis angles of mouse and rat AVFs are similar to human brachiocephalic AVFs (~70-90°) and radiocephalic AVFs (~30-60°) in the literature, respectively. These data suggest the clinical relevance of our rodent AVF models and set the stage for future studies on how these geometrical parameters affect AVF maturation and the mechanisms leading to geometrical changes.
Funding
- NIDDK Support