Evaluation of clip artefacts in three-dimensional computed tomography

Area of Science:

• Neurosurgery
• Radiology
• Medical Imaging

Background:

• Three-dimensional CT angiography (3D-CTA) is increasingly used for postoperative evaluation after aneurysm clipping.
• Digital subtraction angiography is the current standard, but 3D-CTA may offer advantages if image quality issues are addressed.

Purpose of the Study:

• To evaluate the influence of titanium clip orientation on 3D-CTA image quality.
• To quantitatively assess titanium clip artifacts in 3D-CTA.
• To identify predictors of good image quality for postoperative aneurysm assessment.

Main Methods:

• Four types of titanium aneurysm clips were tested on an acrylic glass tablet.
• Standardized 3D-CTA scans were performed at varying clip-gantry angles (0, 45, 90 degrees).
• Multiplanar reconstructions were analyzed by four observers to assess image quality and artifact severity.

Main Results:

• Clip artifacts were primarily along the clip's long axis at 0 degrees, with good quality laterally.
• Artifacts shifted laterally with decreasing clip-gantry angles (90 and 45 degrees).
• Lateral reconstructions showed consistent image quality irrespective of clip-gantry angle.

Conclusions:

• 3D-CTA image quality is significantly affected by titanium clip artifacts.
• Artifact expression and distribution depend on clip-gantry angle and reconstruction plane.
• No direct correlation was found between clip-gantry angle and artifact severity or distribution.