Publications by authors named "Marie Fargier-Voiron"
Article Synopsis
- * The study analyzes the use of the Papillon device, which delivers low energy X-rays for radiotherapy, allowing dose escalation without harming surrounding tissues.
- * Results from treating 24 patients showed a 96% organ preservation rate and an 8% local relapse rate after a median follow-up of 43 months, with no severe toxicities, indicating Papillon as a promising alternative to surgery.
Background: Cardiac arrhythmias, such as ventricular tachycardia, are disruptions in the normal cardiac function that originate from problems in the electrical conduction of signals inside the heart. Recently, a non-invasive treatment option based on external photon or proton beam irradiation has been used to ablate the arrhythmogenic structures. Especially in proton therapy, based on its steep dose gradient, it is crucial to monitor the motion of the heart in order to ensure that the radiation dose is delivered to the correct location.
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- The study compares two prostate radiotherapy monitoring devices: intra-prostatic electromagnetic transmitters (EM-T) and transperineal ultrasound imaging (TP-US), both tested on phantoms and patients for accuracy.* -
- Phantom tests showed minimal interference between the devices, with less than 0.5 mm deviation during translations, but larger systematic shifts were noted during rotations (up to 6.9 mm for TP-US and 3.8 mm for EM-T).* -
- Overall, both devices demonstrated strong correlation in measurements for most patients, making them viable options for monitoring prostate cancer treatment, despite some discrepancies mainly linked to prostate movement and gas presence.*
Purpose: The aim of this study was to evaluate a new system based on transperineal ultrasound (TP-US) acquisitions for prostate and post-prostatectomy pre-treatment positioning by comparing this device to cone-beam computed tomography (CBCT).
Methods: The differences between CBCT/CT and TP-US/TP-US registrations were analyzed on 427 and 453 sessions for 13 prostate and 14 post-prostatectomy patients, respectively. The inter-operator variability (IOV) of the registration process, and the impact and variability of the probe pressure were also evaluated.
Development of 2D+T tracking algorithm in ultrasound images for radiotherapy.
Annu Int Conf IEEE Eng Med Biol Soc
August 2015
The aim of this study is to develop and validate a deformable tracking algorithm for monitoring the motion of the target volume on 2D ultrasound (US) images during a radiotherapy fraction. The proposed method is applied on images acquired with a transperineal ultrasound (TP-US) probe on 31 treatment patient's sessions, treated with a prostate or after a surgery, called a prostatectomy. The developed algorithm is based on Speeded-Up Robust Features (SURF) to find and match the corresponding salient points in the reference and moving images, and Thin Plate Spline (TPS) to warp the image.
View Article and Find Full Text PDFPurpose: To evaluate the accuracy of an intra-modality trans-abdominal ultrasound (TA-US) device against soft-tissue based Cone-Beam Computed tomography (CBCT) registration for prostate and post-prostatectomy pre-treatment positioning.
Methods: The differences between CBCT and US shifts were calculated on 25 prostate cancer patients (cohort A) and 11 post-prostatectomy patients (cohort B), resulting in 284 and 106 paired shifts for cohorts A and B, respectively. As a second step, a corrective method was applied to the US registration results to decrease the systematic shifts observed between TA-US and CBCT results.
Purpose: The aim of the present work is to propose and evaluate registration algorithms of three-dimensional (3D) transabdominal (TA) ultrasound (US) images to setup postprostatectomy patients during radiation therapy.
Methods: Three registration methods have been developed and evaluated to register a reference 3D-TA-US image acquired during the planning CT session and a 3D-TA-US image acquired before each treatment session. The first method (method A) uses only gray value information, whereas the second one (method B) uses only gradient information.
Purpose: To evaluate the impact of transabdominal probe pressure on prostate positioning with an intramodality ultrasound (US) image-guided-radiotherapy system and to quantify pressure variability over the treatment course.
Material And Methods: 8 prostate cancer patients (group A) and 17 healthy volunteers underwent 3 consecutive US images with increasing probe pressure levels, and 1 CT acquisition for the group A only. Prostate positions were compared after manual registration of the first US image contour projected on 2 others.