Gas bubbles in polymethylmethacrylate cranioplasty simulating abscesses: CT appearance

Area of Science:

• Neurosurgery
• Radiology
• Biomaterials Science

Background:

• Cranioplasty is a surgical procedure to repair skull defects.
• Polymethylmethacrylate (PMMA) is a common biomaterial used in cranioplasty.
• CT imaging is frequently used to assess cranioplasty outcomes.

Purpose of the Study:

• To evaluate the CT appearance of PMMA cranioplasty plates.
• To determine the cause and significance of gas bubbles observed in PMMA plates.
• To improve the accuracy of CT interpretations for PMMA cranioplasty.

Main Methods:

• Retrospective review of 20 patients who underwent PMMA cranioplasty.
• Analysis of 17 CT examinations performed on 9 patients.
• Correlation of CT findings with clinical indications and plate characteristics.

Main Results:

• Gas bubble-like appearance was noted in 16 out of 17 CT scans of PMMA plates.
• The appearance of gas bubbles was stable over time, suggesting a non-clinical origin.
• Initial CT interpretations were often variable, inconclusive, or incorrect.

Conclusions:

• The presence of gas bubbles in PMMA cranioplasty plates on CT is a common, stable finding.
• Accurate interpretation requires knowledge of PMMA plate characteristics and potential artifacts.
• Familiarity with PMMA plate imaging is essential to prevent misinterpretation and unnecessary clinical interventions.