-Original-

New Image Processing Method for Plain Radiography Improves Detection of Bone Metastases

Yasuyuki Kitagawa^1,2, Yushi Yamaguchi², Keisuke Atsumi², Yuki Katano², Kazuma Miura¹, Daiki Saito², Eishi Nakamura², Yuta Mohri², Naohiko Tomita² and Tokifumi Majima²

¹Department of Orthopaedic Surgery, Nippon Medical School Tama Nagayama Hospital, Tokyo, Japan
²Department of Orthopaedic Surgery, Nippon Medical School, Tokyo, Japan

Background: Diagnosis of bone metastases would be hastened if they could be detected on plain radiographs obtained at the first visit to an orthopedic surgeon. However, lesions are often undetectable on plain radiography. Bone metastasis is diagnosed at the first visit in only a few patients, and diagnosis is delayed in many cases. We investigated the diagnostic performance of plain radiography that used a new image processing method, Dynamic Visualization II (DV), to diagnose bone metastases.
Methods: We enrolled 29 patients with symptomatic pelvic bone metastases who visited our hospital between April 2018 and March 2021. The evaluation images were created by processing the original plain radiography data with the default settings for DV (Presets 1-4). Processing with Preset 1 resulted in an image converted to conventional film parameters, whereas Presets 2-4 utilized different DV processing methods. The readers were six orthopedic trainees, and the reading time was 30 seconds per image. The rate of correct answers for images processed with Preset 1 was compared to the rates for those processed with the other presets. Additionally, the rate of correct answers was analyzed in relation to clinical variables.
Results: The correct answer rate was significantly higher for Preset 3 (43.7%) and Preset 4 (42.5%) than for Preset 1 (28.7%). Correct answer rates for Presets 3 and 4 were significantly higher for elderly patients, male patients, patients with innominate bone lesions, patients with osteolytic bone metastases, and patients with a normal body weight.
Conclusions: Image processing by DV improved diagnosis of bone metastases by plain radiography. DV might hasten diagnosis of bone metastases and help prevent associated complications.

J Nippon Med Sch 2025; 92: 37-43

Keywords
bone metastasis, plain radiography, image processing, Dynamic Visualization II

Correspondence to
Yasuyuki Kitagawa, MD, Department of Orthopaedic Surgery, Nippon Medical School Tama Nagayama Hospital, 1-7-1 Nagayama, Tama, Tokyo 206-8512, Japan
kitayasu@nms.ac.jp

Received, July 9, 2024
Accepted, September 30, 2024