Detection of orbital foreign bodies with computed tomography: current limits

Area of Science:

• Ophthalmology
• Radiology
• Medical Imaging

Background:

• Orbital foreign bodies pose diagnostic challenges.
• Accurate detection and localization are crucial for treatment planning.
• Computed tomography (CT) is a common imaging modality for orbital injuries.

Purpose of the Study:

• To evaluate the efficacy of CT for detecting and localizing orbital foreign bodies.
• To determine the minimum detectable size of various materials using CT.
• To assess CT performance under simulated in vivo conditions.

Main Methods:

• A model simulating in vivo conditions was used for evaluation.
• The GE 8800 computed tomography scanner was employed.
• Detection and localization accuracy were assessed for different foreign body materials and sizes.

Main Results:

• The GE 8800 scanner demonstrated excellent detection and localization for most orbital foreign bodies.
• Minimum detectable sizes varied by material: 0.06 mm³ for steel, 1.82 mm³ for intraocular auto window glass.
• Small wood fragments were not detected by the scanner.

Conclusions:

• CT is a valuable tool for identifying and locating most orbital foreign bodies.
• Material properties significantly influence CT detection limits.
• CT may not be suitable for detecting very small or low-density foreign bodies like wood fragments.