3D Reconstruction to Detect Fish Bones in Foreign Body Models

Abstract

Objective: When fish bones are impacted in pharynx or in esophagus, it’s hard to find them with simple radiography. We designed foreign body models with fish bones and used their computed tomogram data to make 3D reconstructed images. Various modifications of 3D data were tested for foreign body detection.

Method: Bones from 3 species of fishes frequently consumed in Korea were used as foreign body models. Fish bones were sandwiched between plates of fish paste. Computed tomograms taken were converted into 3D images. Multi-planar reconstruction, volume rendering, and virtual endoscopy were used to determine the characteristics of fish bones.

Results: Shapes of the bones are easily reconstructed for the mandible. Gill cover and spine cannot be reconstructed perfectly. The shape could be figured out in every reconstructed image in volume rendered images after removal of soft tissue data. In measuring size, plane CT are useful in detecting margins. Volume rendered images also were suitable in measuring the size. The location of the foreign bodies could be easily measured if the reference point is given. The axial CT image or 3D images are both useful in calculating distance from the reference point. In view of orientation, 3D images are best of all.

Conclusion: Searching for fish bones and gathering information about them are difficult tasks in esophageal foreign body cases. Fish bone foreign body models and their reconstructed images are useful in getting information about size, shape, location, and orientation. This technique could be applied in finding real fish bone foreign bodies.