Interobserver variability in physician-modified endograft planning by comparison with a three-dimensional printed...

Area of Science:

• Vascular Surgery
• Medical Imaging
• Biomedical Engineering

Background:

• Increasing use of fenestrated endografts for aneurysm repair raises concerns about CT scan measurement accuracy.
• Inaccurate measurements can lead to the 'eclipsing' phenomenon, where fenestrations misalign with vessel ostia.
• This study investigates discrepancies between CT-based measurements and physical 3D models.

Purpose of the Study:

• To compare the accuracy of vessel position measurements from CT scan reconstructions versus physical 3D printed models.
• To evaluate potential inaccuracies in measurements crucial for fenestrated endografting.
• To identify if measurement discrepancies contribute to the 'eclipsing' phenomenon.

Main Methods:

• 3D reconstructions of the visceral aortic segment were created using medical modeling software.
• Physical 3D models were generated for precise measurement of vessel angles and distances.
• Blinded reviewers obtained measurements, which were statistically analyzed for accuracy and precision.

Main Results:

• Measurements for the superior mesenteric artery (SMA) bottom and renal artery top/bottom were statistically accurate.
• Significant variability and inaccuracy were found in all visceral vessel angles and the celiac artery bottom.
• CT-based measurements did not consistently represent true vessel positions, especially for angles.

Conclusions:

• While visceral vessel orifices are mostly accurately measured, vessel angles present significant inaccuracies.
• Imprecise angle measurements can lead to the eclipsing phenomenon, potentially causing fenestrated graft failure.
• Further research is needed to understand the clinical impact of eclipsing and improve fenestration accuracy to prevent reintervention.