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Anton Deguet

Publications and source records attributed to Anton Deguet.

3 recordsLinked to original sources

MRI image overlay: applications to arthrography needle insertion.

Magnetic Resonance Imaging (MRI) has unmatched potential for planning, guiding, monitoring and controlling interventions. MR arthrography (MRA) is the imaging gold standard to assess small ligament and fibrocartilage injury in joints. In contemporary practice, MRA consists of two consecutive sessions: 1) an interventional session where a needle is driven to the joint space and gadolinium contrast is injected under fluoroscopy or CT guidance. 2) A diagnostic MRI imaging session to visualize the distribution of contrast inside the joint space and evaluate the condition of the joint. Our approach to MRA is to eliminate the separate radiologically guided needle insertion and contrast injection procedure by performing those tasks on conventional high-field closed MRI scanners. We propose a 2D augmented reality image overlay device to guide needle insertion procedures. This approach makes diagnostic high-field magnets available for interventions without a complex and expensive engineering entourage.

Arthrography↗

Image overlay guidance for needle insertion in CT scanner.

We present an image overlay system to aid needle insertion procedures in computed tomography (CT) scanners. The device consists of a display and a semitransparent mirror that is mounted on the gantry. Looking at the patient through the mirror, the CT image appears to be floating inside the patient with correct size and position, thereby providing the physician with two-dimensional (2-D) "X-ray vision" to guide needle insertions. The physician inserts the needle following the optimal path identified in the CT image rendered on the display and, thus, reflected in the mirror. The system promises to reduce X-ray dose, patient discomfort, and procedure time by significantly reducing faulty insertion attempts. It may also increase needle placement accuracy. We report the design and implementation of the image overlay system followed by the results of phantom and cadaver experiments in several clinical applications.

Biopsy↗

Image overlay for CT-guided needle insertions.

OBJECTIVE: We present a 2D image overlay device to assist needle placement on computed tomography (CT) scanners. MATERIALS AND METHODS: The system consists of a flat display and a semitransparent mirror mounted on the gantry. When the physician looks at the patient through the mirror, the CT image appears to be floating inside the body with correct size and position as if the physician had 2D 'X-ray vision'. The physician draws the optimal path on the CT image. The composite image is rendered on the display and thus reflected in the mirror. The reflected image is used to guide the physician in the procedure. In this article, we describe the design and various embodiments of the 2D image overlay system, followed by the results of phantom and cadaver experiments in multiple clinical applications. RESULTS: Multiple skeletal targets were successfully accessed with one insertion attempt. Generally, successful access was recorded on liver targets when a clear path opened, but the number of attempts and accuracy showed variability because of occasional lack of access. Soft tissue deformation further reduced the accuracy and consistency in comparison to skeletal targets. CONCLUSION: The system demonstrated strong potential for reducing faulty needle insertion attempts, thereby reducing X-ray dose and patient discomfort.

Animals↗