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Featured researches published by G. Fiard.


Urology | 2013

Targeted MRI-guided Prostate Biopsies for the Detection of Prostate Cancer: Initial Clinical Experience With Real-time 3-Dimensional Transrectal Ultrasound Guidance and Magnetic Resonance/Transrectal Ultrasound Image Fusion

G. Fiard; N. Hohn; Jean-Luc Descotes; Jean-Jacques Rambeaud; Jocelyne Troccaz; J.-A. Long

OBJECTIVE To prove the feasibility and evaluate the initial clinical results of targeted prostate biopsies using the Urostation novel platform using magnetic resonance imaging (MRI)/transrectal ultrasound (TRUS) registration to help steer the biopsy needle to suspicious areas. METHODS We prospectively included 30 patients for suspicion of prostate cancer from November 2011 to August 2012. All patients were previously evaluated by a multiparametric MRI, interpreted by a single radiologist who attributed a Prostate Imaging-Reporting and Data System (PI-RADS) score to each lesion. A conventional 12-core randomized biopsy protocol was performed and 2 additional targeted biopsies were performed on suspicious area(s). The results of randomized and targeted biopsies were compared. RESULTS Among the 30 patients, suspicious area(s) were found on MRI in 20 cases (67%). Median procedure time was 23 minutes. Targeting success rate (biopsy visualized inside the target) was 83%, with at least 1 biopsy reaching the target in all cases. Prostate cancer was detected in 14 cases (47%), including 11 cases with an abnormal MRI. Targeted biopsies detected cancer in all 11 cases and all but 1 were clinically significant. Randomized biopsies detected 10 of these 11 cases, and 3 more cases that MRI considered normal. Sensitivity to detect a significant cancer was 91% in both modalities. CONCLUSION This initial clinical study showed encouraging results for targeted MRI-guided prostate biopsies using MRI-TRUS fusion. Although further studies are needed to determine the role of prostate MRI before biopsy and the relevance of targeted biopsies, the Urostation is an MRI-TRUS fusion device that has good accuracy for targeting suspicious areas on MRI.


BJUI | 2013

External validation of the RENAL nephrometry score in renal tumours treated by partial nephrectomy

J.-A. Long; Valentin Arnoux; G. Fiard; Riccardo Autorino; Jean-Luc Descotes; Jean-Jacques Rambeaud; B. Boillot; N. Terrier; Alexis Arvin-Berod; Alexandre Moreau-Gaudry

Using a standardized classification for renal tumours is a major step towards an objective comparison of the indications and expected outcomes of partial nephrectomy (PN). Several scores have been described, including the RENAL nephrectomy score (RNS), to evaluate the anatomical features of a renal tumour and predict the surgical challenges with particular regard to PN. Previous studies show discrepancies with regard to the effectiveness of using the RNS to predict postoperative outcomes. Although we showed that conversion to radical nephrectomy was predicted by the RNS, the occurence of complications was more difficult to predict.


BJUI | 2013

High-grade renal injury: non-operative management of urinary extravasation and prediction of long-term outcomes.

J.-A. Long; G. Fiard; Jean-Luc Descotes; Valentin Arnoux; Alexis Arvin-Berod; N. Terrier; B. Boillot; Olivier Skowron; Caroline Thuillier; Jean-Jacques Rambeaud

Study Type – Therapy (outcomes)


The Journal of Urology | 2016

High Grade Blunt Renal Trauma: Predictors of Surgery and Long-Term Outcomes of Conservative Management. A Prospective Single Center Study

C. Lanchon; G. Fiard; Valentin Arnoux; Jean-Luc Descotes; Jean-Jacques Rambeaud; N. Terrier; B. Boillot; Caroline Thuillier; Delphine Poncet; J.-A. Long

PURPOSE The management of major renal trauma has shifted in the last decade in favor of a nonoperative approach. Our level 1 trauma center promotes this approach with the objective of renal function preservation. However, certain situations still require surgery. In this study we analyze predictors of surgery and long-term outcomes after conservative management. MATERIALS AND METHODS From January 2004 to March 2015 we prospectively collected data from all patients admitted to our institution for high grade blunt renal trauma (grades IV and V). Nonoperative management was considered successful when patients did not undergo surgical exploration, regardless of angioembolization or endoscopic treatment. RESULTS Of 306 patients with renal trauma 151 presented with major injuries, including 124 grade IV and 27 grade V. Nonoperative management was successful in 110 (89%) cases of grade IV and 14 (52%) cases of grade V lesions. Deceleration mechanism (p=0.03), associated lesions (p=0.001), percentage of devitalized parenchyma (p=0.012), angioembolization (p <0.001), hemodynamic instability (p <0.001) and low hemoglobin (p=0.001) were more frequent in patients treated surgically. On multivariate analysis grade (OR 7.36, p=0.01) and hemodynamic instability (OR 4.18, p=0.04) were the only independent predictors of surgical treatment. Long-term followup of preserved kidneys revealed a remaining 40% and 0% relative renal function after grade IV and V injuries, respectively. Only devascularized parenchyma greater than 25% predicted the decline of long-term renal function. CONCLUSIONS Nonoperative management can and should be performed safely in cases of grade IV injuries whenever possible, with valuable long-term renal function. It can also be initiated in grade V cases. However, surgeons should consider nephrectomy with the onset of any suspicious symptoms.


The Journal of Urology | 2012

Long-term renal function assessment with dimercapto-succinic acid scintigraphy after conservative treatment of major renal trauma.

G. Fiard; Jean-Jacques Rambeaud; Jean-Luc Descotes; B. Boillot; N. Terrier; Caroline Thuillier; Marine Chodez; Olivier Skowron; Alexis Arvin Berod; Valentin Arnoux; J.-A. Long

PURPOSE The management of high grade blunt renal injury has evolved with time to become increasingly conservative with the ultimate objective of renal preservation. We evaluated relative renal function with dimercapto-succinic acid renal scintigraphy 6 months after major renal trauma (grade IV or V). MATERIALS AND METHODS This prospective observational study was done between January 2004 and April 2010. All patients who presented with grade IV or V renal trauma and were treated conservatively were included in analysis. Patient and trauma characteristics, and initial management were recorded. Relative renal function was evaluated by dimercapto-succinic acid renal scintigraphy 6 months after trauma. RESULTS A total of 88 patients were included in the study. Conservative management was possible in 79 patients (90%), including 69 and 10 with grade IV and V trauma, respectively. Dimercapto-succinic acid renal scintigraphy was done at 6 months for 22 patients (28%). Mean relative renal function for grade IV and V injuries was 39% and 11%, respectively (p=0.0041). The percent of devascularized parenchyma (p=0.0033) and the vascular subtype of grade IV injuries (p=0.0194) also correlated with decreased renal function. No complication or de novo arterial hypertension was noted. CONCLUSIONS Conservative treatment achieves the objective of renal function preservation for grade IV lesions. Grade V and specific subtypes of grade IV injury have a poor functional outcome. Further study must be performed to determine which patients will benefit from conservative treatment vs early nephrectomy to avoid a longer hospital stay and useless procedures.


The Journal of Urology | 2016

Are Magnetic Resonance Imaging-Transrectal Ultrasound Guided Targeted Biopsies Noninferior to Transrectal Ultrasound Guided Systematic Biopsies for the Detection of Prostate Cancer?

Nicolas Barry Delongchamps; D. Portalez; Eric Bruguière; Bernard Malavaud; Pierre Mozer; G. Fiard; F. Cornud; Caroline Escourrou; Stéphanie Renault; Naïm Bouazza; Jean-Michel Casanova; Arachk de Gorski; R. Renard-Penna; Mathieu Roumiguié; M. Thoulouzan; V. Misrai; Julien Guillotreau; Richard Aziza; Jean-Luc Descotes; N. Hohn; Flavie Bratan; Fanny Cros; Thomas Sanzalone

PURPOSE In men with suspicion of prostate cancer the standard of cancer detection is transrectal ultrasound guided 10 to 12-core systematic biopsy. The targeted biopsy only strategy using magnetic resonance imaging-transrectal ultrasound image registration is gaining in popularity. We assessed the noninferiority of targeted vs systematic biopsy. MATERIALS AND METHODS Between June and October 2014 a total of 108 biopsy naïve patients with prostate specific antigen between 4 and 20 ng/ml, normal rectal examination and a single suspicious image on magnetic resonance imaging were included in study at 7 centers. Patients underwent systematic biopsy by a first operator blinded to magnetic resonance imaging, immediately followed by 3 targeted biopsies within the suspicious image by a second operator. The primary end point was the cancer detection rate. The noninferiority margin was set at -5%. The secondary end points were the detection rate of clinically significant prostate cancer (maximum cancer core length 5 mm or greater for Gleason 6 or any Gleason 7 or greater disease) and procedure duration. RESULTS Systematic and targeted biopsies detected cancer in 66 (61.1%) and 61 patients (56.5%), respectively. The mean difference was -4.5% with a 95% CI lower bound of -11.8%. A total of 13 patients with protocol violations were excluded from the per protocol analysis, which showed a mean difference of -5.2% with a 95% CI lower bound of -13.1%. Clinically significant prostate cancer was detected in 50 (46.2%) and 52 patients (48.1%) with systematic and targeted biopsies, respectively (p = 0.69). The mean ± SD duration of image fusion plus targeted biopsy was 16.7 ± 7 minutes vs 7.4 ± 3 for systematic biopsy (p <0.001). CONCLUSIONS Targeted biopsy seemed to be inferior to systematic biopsy for overall cancer detection. Detection of clinically significant prostate cancer did not differ between targeted and systematic biopsies.


computer based medical systems | 2013

A virtual reality simulator combining a learning environment and clinical case database for image-guided prostate biopsy

Sonia-Yuki Selmi; G. Fiard; Emmanuel Promayon; Lucile Vadcard; Jocelyne Troccaz

The recent availability of navigation systems for mapping and targeting of transrectal ultrasound (TRUSS) guided prostate biopsies revealed new opportunities in training the clinician. This paper describes a simulator for TRUSS guided prostate biopsy that offers similar information, enhanced by a complete learning environment. Various exercises have been developed in accordance with a didactical study identifying the training needs. A dedicated clinical case database fed by a prostate navigation system provides a large patient prostate image database that covers the main situations encountered during clinical practice. A haptic device is used to enable complete biopsy procedures or practice specific tasks. This paper also presents work in progress of the evaluation of such a simulator.


Journal of Endourology | 2014

Initial Validation of a Virtual-Reality Learning Environment for Prostate Biopsies: Realism Matters!

G. Fiard; Sonia-Yuki Selmi; Emmanuel Promayon; Lucile Vadcard; Jean-Luc Descotes; Jocelyne Troccaz

BACKGROUND AND PURPOSE A virtual-reality learning environment dedicated to prostate biopsies was designed to overcome the limitations of current classical teaching methods. The aim of this study was to validate reliability, face, content, and construct of the simulator. MATERIALS AND METHODS The simulator is composed of (a) a laptop computer, (b) a haptic device with a stylus that mimics the ultrasound probe, (c) a clinical case database including three-dimensional (3D) ultrasound volumes and patient data, and (d) a learning environment with a set of progressive exercises including a randomized 12-core biopsy procedure. Both visual (3D biopsy mapping) and numerical (score) feedback are given to the user. The simulator evaluation was conducted in an academic urology department on 7 experts and 14 novices who each performed a virtual biopsy procedure and completed a face and content validity questionnaire. RESULTS The overall realism of the biopsy procedure was rated at a median of 9/10 by nonexperts (7.1-9.8). Experts rated the usefulness of the simulator for the initial training of urologists at 8.2/10 (7.9-8.3), but reported the range of motion and force feedback as significantly less realistic than novices (P=0.01 and 0.03, respectively). Pearson r correlation coefficient between correctly placed biopsies on the right and left side of the prostate for each user was 0.79 (P<0.001). The 7 experts had a median score of 64% (59%-73%), and the 14 novices a median score of 52% (43%-67%), without reaching statistical significance (P=0.19). CONCLUSION The newly designed virtual-reality learning environment proved its versatility and its reliability, face, and content were validated. Demonstrating the construct validity will necessitate improvements to the realism and scoring system used.Abstract Background and Purpose: A virtual-reality learning environment dedicated to prostate biopsies was designed to overcome the limitations of current classical teaching methods. The aim of this study was to validate reliability, face, content, and construct of the simulator. Materials and Methods: The simulator is composed of (a) a laptop computer, (b) a haptic device with a stylus that mimics the ultrasound probe, (c) a clinical case database including three-dimensional (3D) ultrasound volumes and patient data, and (d) a learning environment with a set of progressive exercises including a randomized 12-core biopsy procedure. Both visual (3D biopsy mapping) and numerical (score) feedback are given to the user. The simulator evaluation was conducted in an academic urology department on 7 experts and 14 novices who each performed a virtual biopsy procedure and completed a face and content validity questionnaire. Results: The overall realism of the biopsy procedure was rated at a median of 9/10 by nonex...


Journal of Endourology | 2016

Surgical Staff Radiation Protection During Fluoroscopy-Guided Urologic Interventions.

François Galonnier; Olivier Traxer; Maeva Rosec; Jean-Baptiste Terrasa; Pascal Gouezel; David Celier; Céline Bassinet; A. Ruffion; Philipe Paparel; G. Fiard; J. Terrier

INTRODUCTION Over the past 20 years, the use of fluoroscopy to guide urologic surgical interventions has been constantly growing. Thus, in their daily practice, urologists and other operating room (OR) staff are exposed to X-radiation increasingly frequently. This raises questions as to the risks they encounter and the actions needed to reduce them. OBJECTIVE Evaluate X-ray dose exposure in the members of the surgical team and determine urologist radioprotection knowledge and practices. MATERIALS AND METHODS A prospective bicenter study was conducted within AFUF (French urology resident association) and in association with The French Nuclear Safety Authority/The Institute for Radiological Protection and Nuclear Safety (ASN/IRSN). Radiation exposure was measured on 12 operators using dosimeters (seven per operator), in staff-occupied locations in the OR using ionization chambers, and on anthropomorphic phantoms. A survey was used to gather information on radiation knowledge and safety practices of the AFUF members. RESULTS Annual whole-body radiation doses were low (0.1-0.8 millisieverts [mSv], mostly at around 0.3 mSv), and equivalent doses were low for the fingers (0.7-15 mSv, mostly at around 2.5 mSv), and low for the lens of the eye (0.3-2.3 mSv, mostly at around 0.7 mSv). In percutaneous nephrolithotomy, extremity doses were lower when the patient was placed in dorsal decubitus compared with ventral decubitus. Pulsed fluoroscopy reduced radiation dose exposure by a factor of 3 compared with continuous fluoroscopy with no image quality loss. Radiation safety practices were poor: only 15% of urologists wore dosimeters and only 5% had been trained in the handling of X-ray generators. CONCLUSION In the present study, radiation exposure for urologists was low, but so was knowledge of radiation safety and optimization practices. This absence of training for radiation safety and reduction, teamed with novel techniques involving long fluoroscopy-guided interventions, could result in unnecessarily high exposure for patients and OR personnel.


international conference of the ieee engineering in medicine and biology society | 2013

Using CamiTK for rapid prototyping of interactive Computer Assisted Medical Intervention applications

Emmanuel Promayon; Céline Fouard; Mathieu Bailet; Aurélien Deram; G. Fiard; Nikolai Hungr; Vincent Luboz; Yohan Payan; Johan Sarrazin; Nicolas Saubat; Sonia Yuki Selmi; Sandrine Voros; Philippe Cinquin; Jocelyne Troccaz

Computer Assisted Medical Intervention (CAMI hereafter) is a complex multi-disciplinary field. CAMI research requires the collaboration of experts in several fields as diverse as medicine, computer science, mathematics, instrumentation, signal processing, mechanics, modeling, automatics, optics, etc. CamiTK1 is a modular framework that helps researchers and clinicians to collaborate together in order to prototype CAMI applications by regrouping the knowledge and expertise from each discipline. It is an open-source, cross-platform generic and modular tool written in C++ which can handle medical images, surgical navigation, biomedicals simulations and robot control. This paper presents the Computer Assisted Medical Intervention ToolKit (CamiTK) and how it is used in various applications in our research team.

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J.-A. Long

University of Grenoble

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N. Terrier

University of Grenoble

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B. Pradere

François Rabelais University

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B. Boillot

University of Grenoble

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N. Brichart

François Rabelais University

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N. Hohn

University of Grenoble

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