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Session: Multi-Disciplinary General ePoster Viewing [Return to Session]

Dual-Energy Radiography for Improved Detection of Retained Foreign Objects

H Zhang1, L Hahn2, H Guo3, A Wang4*, (1) Memorial Sloan Kettering Cancer Center, New York, NY, (2) University of California, San Diego, CA,(3) Stanford University, Stanford, CA,(4) Stanford University, Stanford, CA


PO-GePV-M-331 (Sunday, 7/10/2022)   [Eastern Time (GMT-4)]

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Purpose: Retained foreign objects (RFOs) after surgery are supposed to be “never events” but still occur, leading to pain, complications, and even death. Radiography is commonly used to detect RFOs with low radiation exposure after surgery. However, some RFOs are difficult to identify on radiography especially when overlapping with bones or other anatomy. In this work, we investigate the feasibility of using dual-energy radiography to further improve the detection of RFOs, specifically surgical sponges, which are the most common RFO.

Methods: A total of 13 patient CT datasets were selected for this study. We simulated low-energy (LE) and high-energy (HE) projections of the CTs, for realistic anatomy in the chest, abdomen, and pelvis regions. We then digitally inserted 0-6 surgical sponges at random locations and added Poisson noise to emulate realistic images. From the dual-energy radiography, soft tissue and bone projection images were also generated. In a blind study, an experienced radiologist was asked to find each sponge and identify the image (LE, HE, Soft Tissue, Bone) that was the easiest to locate each sponge.

Results: Compared to the LE and HE projections, the noise in the soft tissue and bone projections was substantially amplified. Nevertheless, all 37 surgical sponges were successfully identified by the radiologist. 35 (95%) of the sponges were identified on the bone projection images, while 2 (5%) were identified on the soft tissue projection images. The radiologist found the most effective images to locate the sponges were in the order of: Bone > Soft tissue > LE >> HE.

Conclusion: We have demonstrated the feasibility and efficacy of using dual-energy radiography to improve the detection of surgical sponges. This study shows the decomposed bone projection is the most effective in finding surgical sponges. Future work can include other surgical objects such as needles and other instruments.


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