SU‐G‐IeP3‐03: Dual‐Filament, Multi‐Facet Anode Design to Overcome Small Focal Spot Output Limitations

Abstract

Purpose: Demonstrate the advantages of two novel x‐ray tube‐insert designs to overcome tube output limitations for high‐resolution, small field‐of‐view (FOV) angiographic imaging. Methods: High‐spatial resolution with a small focal spot (sfs) is achievable with the microangiographic (MA) detector that we have developed. The two designs explored are a non‐offset design, and an offset design. Both tube‐insert designs include two filaments, L1 and L2, and two focal target tracks. L1 corresponds to an 8° anode region to produce a medium effective focal spot (mfs) to be used with the standard FOV flat‐panel detector (FPD). L2 corresponds to a 2° anode region to produce a small effective focal spot (sfs) to be used with the smaller FOV MA detector, while providing comparable x‐ray output. The non‐offset design has the sfs region closer to the anode rotation axis, and mfs region farther from the axis. The offset design has the mfs region closer to the rotation axis, and sfs region farther from the rotation axis. The sfs region of the offset design has a greater anode track diameter which may further increase output capability. However, in order to avoid limitations on the mfs FOV in this design, the sfs target region of the anode is offset in the anode cathode direction. The geometries of both designs are illustrated and compared. Results: It is shown that the new designs enable increased tube output for the sfs when used with a small FOV detector, while also allowing for increased FOV with the standard FPD and the mfs. Conclusion: A dual track, dual filament x‐ray tube‐insert design provides increased output capability over a small FOV, while enabling an mfs to be used with the lower resolution standard FPD. Toshiba Medical Systems Corp