Carotid Aneurysm Model

Indication and Application:
Neurointerventional device validation (e.g., Flow Diverters, Embolization Coils, Intra-saccular Flow Disruptors, Liquid Embolic Agents), hemodynamic flow-dynamics modification research, and aneurysm rupture/healing mechanism profiling.

Modeling Method:
- Surgical Venous Pouch Method (Gold Standard for Device Testing): An autologous vein segment (e.g., jugular vein) is harvested, fashioned into a pouch, and anastomosed end-to-side to the bifurcated or isolated common carotid artery under high-magnification microsurgery.
- Chemical Elastase Perfusion Method: Localized intraluminal incubation of the carotid artery with porcine pancreatic elastase, inducing enzymatic degradation of the arterial wall matrix to form a fusiform or saccular aneurysm.

Clinical Relevance:
- Hemodynamic and Morphological Simulation: The surgical creation of a saccular aneurysm pouch perfectly mimics the intra-saccular vortices, low wall shear stress (WSS), and high pressure found in human intracranial and extracranial aneurysms. 
- Device Delivery and Deployability: Large animal variations (canine and porcine models) match human carotid and cerebral arterial geometry, vessel diameters, and tortuosity. This provides an irreplaceable tactile feedback and anatomical platform for testing the trackability, deployment precision, and sizing of human-grade catheters, coils, and flow-diverting stents.

Key Evaluation Endpoints:

1. In Vivo / Surgical / Imaging:
- Digital Subtraction Angiography (DSA): Standardized Raymond-Roy Occlusion Classification to grade immediate and long-term aneurysm occlusion post-embolization.
- Optical Coherence Tomography (OCT) and High-Resolution Ultrasound: Evaluation of intra-stent tissue coverage and parent artery patency.
- Fluroscopic tracking of device migration, compaction, or recanalization.

2. Histopathology:
- Neointimal Healing Profile (Gold Standard): Gross examination and plastic/paraffin embedding sections to evaluate tissue neck-bridging and endothelialization across the aneurysm orifice.
- H&E, Masson's Trichrome, and Movat's Pentachrome staining to quantify intra-saccular thrombus organization, collagen maturation, and parental vessel wall integrity.
- IHC/IF for CD31/vWF (endothelial layer continuity) and alpha-SMA (smooth muscle cell coverage over the neck).

3. Molecular:
- Quantification of matrix metalloproteinases (MMP-2, MMP-9) and inflammatory cascades (IL-1beta, TNF-alpha) to assess enzymatic degradation or local biocompatibility profiles.