At present, orthopaedic surgeons utilize either CT, MRI or X-ray for imaging a joint. Unfortunately, CT and MRI are quite expensive, non weight-bearing and the orthopaedic surgeon does not receive revenue for these procedures. Although x-rays are cheaper, similar to CT scans, patients incur radiation. Also, all three of these imaging modalities are static. More recently, a new ultrasound technology has been developed that will allow a surgeon to image their patients in 3D. The objective of this study is to highlight the new opportunity for orthopaedic surgeons to use 3D ultrasound as alternative to CT, MRI and X-rays. The 3D reconstruction process utilizes statistical shape atlases in conjunction with the ultrasound RF data to build the patient anatomy in real-time. The ultrasound RF signals are acquired using a linear transducer. Raw RF data is then extracted across each scan line. The transducer is tracked using a 3D tracking system. The location and orientation for each scan line is calculated using the tracking data and known position of the tracker relative to the signal. For each scan line, a detection algorithm extracts the location on the signal of the bone boundary, if any exists. Throughout the scan process, a 3D point cloud is created for each detected bone signal. Using a statistical bone atlas for each anatomy, the patient specific surface is reconstruction by optimizing the geometry to match the point cloud. Missing regions are interpolated from the bone atlas. To validate reconstructed models output models are then compared to models generated from 3D imaging, including CT and MRI.Introduction
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