Development and tracking of inferior vena cava diameter after filter placement using a circle-fitting predictive model.

The diameter of the inferior vena cava (IVC) is a critical factor in the decision-making process for IVC filter (IVCF) placement. A mismatched filter can compromise its stability and potentially lead to adverse events. This study develops and validates a predictive model using a circle-fitting algorithm to estimate the IVC diameter after filter placement. The findings suggest that single-angle measurements may misrepresent the filter-vessel compatibility, since the IVC transforms from an oval to a near-circular cross-section following filter placement. The predictive model, integrating three-dimensional, multi-angle cavography with circumference-based calculations, demonstrates excellent concordance with both post-placement maximum and minimum diameters in animal and clinical samples. Compared to the conventional single-angle measurements prior to IVCF placement, the predictive diameter can provide a more accurate and reliable representation of the IVC size, which was superior to either the maximum or minimum diameter alone, suggesting a higher predictive reliability. This model may provide a valuable tool for more accurate IVCF diameter selection and support future research.