Safety and Operability Assessment of a Terminal-Loop Flow Diverter in a Canine Intracranial Aneurysm Model

JingBo Liu; GaiPing Zhao

doi:10.63313/hmt.9020

Authors

JingBo Liu School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China Author
GaiPing Zhao School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China Author

DOI:

https://doi.org/10.63313/hmt.9020

Keywords:

Safety, Operability, Beagle model, Short-term implantation

Abstract

Objective: This study aims to evaluate the safety and operability of a self-developed terminal-loop flow diverter following short-term implantation (preoperative, postoperative, and 90-day follow-up) in a beagle intracranial aneurysm model. Specifically, the investigation focuses on whether the device can be delivered, deployed, and visualized effectively during surgery, and whether it induces any adverse effects on coagulation function, histopathology, or general health within the 90-day observation period.

Method: The protocol employed a self-controlled design. Six healthy beagles were selected, with the control device implanted in the left carotid artery and the test device implanted in the right carotid artery. Data were collected at three time points: pre-operatively, immediately post-operatively, and 90 days post‑operatively, using methods including digital subtraction angiography, hematological analysis, and histopathological examination. The objective was to evaluate device-related vascular complications, local tissue response, and biocompatibility.All experimental animals were subjected to a self-controlled study design, with angiographic assessments performed preoperatively, immediately postoperatively, and at the study endpoint (90 days post-implantation). Immediate postoperative DSA demonstrated clear fluoroscopic visualization of the device, with successful implantation and deployment and no occurrence of vascular complications; follow-up angiography at 90 days post-implantation confirmed sustained clear device visibility and the absence of vascular complications. Operability was evaluated based on the following parameters recorded during the implantation procedure: overall handling, deployment performance, fluoroscopic visibility, Trackability, Shape retention and Vessel wall apposition.

Results: In the 90-day follow-up, all animals survived without serious complications. Immediate and 90-day DSA confirmed clear fluoroscopic visualization of the terminal-loop flow diverter, with successful implantation and no vascular injury. Coagulation function analysis showed a significant increase in fibrinogen at 90 days (p=0.023), a transient rise and fall in thrombin time (p=0.020), and a significant quadratic trend in INR (p=0.036), while APTT and PT remained stable. Histopathology revealed mainly moderate degeneration in major organs, with no severe adverse changes. Operability assessment indicated that the test device was comparable to the control in overall handling, deployment, and fluoroscopic visibility, with slightly better shape retention, though trackability was superior for the control. The implantation procedure was smooth, and the test device met surgical requirements

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