Preliminary Exploration of CBCT in IVCFT Patient Filter Retrieval.

BACKGROUND

Inferior vena cava filter related thrombosis (IVCFT) poses significant challenges in patients undergoing mechanical thromboembolic prophylaxis, often leading to filter retrieval failure and recurrent pulmonary embolism. Current diagnostic modalities, including ultrasound, CT venography, and digital subtraction angiography (DSA), suffer from limitations such as operator dependency, ferromagnetic interference, patient transfer risks, and suboptimal multiplanar reconstruction capabilities. Cone-beam computed tomography (CBCT), offering real-time three-dimensional vascular imaging within the angiography suite, holds promise for overcoming these barriers. However, its diagnostic accuracy and clinical utility in characterizing IVCFT morphology, thrombus burden, and filter-device interactions remain unestablished. This study aimed to evaluate CBCT's role in optimizing filter retrieval decision-making by integrating preprocedural thrombus phenotyping with intraoperative guidance, thereby establishing a personalized management framework for IVCFT.

AIMS: To evaluate the diagnostic efficacy of cone-beam CT (CBCT) in IVCFT retrieval and analyze thrombus characteristics affecting retrieval outcomes.

METHODS

This prospective study enrolled 20 patients undergoing prophylactic filter placement (August 2024-March 2025) for "one-stop" assessment using intraoperative CBCT 3D rotational angiography combined with DSA. Multidimensional 3D reconstructions were analyzed for thrombus morphology, spatial distribution, and filter-thrombus integration. Diagnostic accuracy was validated through post-retrieval macroscopic examination. Retrieval success rates and contributing factors were statistically analyzed.

RESULTS

Among 16 confirmed IVCFT cases, CBCT demonstrated 100% diagnostic concordance. Thrombus morphology distribution revealed mural (81.3%) versus free-floating (18.7%) patterns. The overall retrieval success rate was 87.5% (14/16). Subanalysis demonstrated 100% success (10/10) with ≤ 60% cross-sectional thrombus burden versus 66.7% (4/6) with > 60% occupancy (p = 0.125). Filters with transaxial thrombus penetration showed lower success rates compared to localized thrombi (75.0% vs. 100%, p = 0.467). Bedridden patients exhibited significantly higher rates of > 60% thrombus burden compared to ambulatory counterparts (83.3% vs. 10.0%, p = 0.008).

CONCLUSION

CBCT provides precise three-dimensional characterization of IVCFT morphology and spatial relationships. Critical thrombus burden ( > 60%) and transfilter penetration emerge as key risk factors for retrieval failure. The CBCT-DSA integrated protocol establishes an optimized decision-making framework for personalized endovascular management.