J. Hubert

The virtual reality simulator dV-Trainer(®) is a valid assessment tool for robotic surgical skills.

BackgroundExponential development of minimally invasive techniques, such as robotic-assisted devices, raises the question of how to assess robotic surgery skills. Early development of virtual simulators has provided efficient tools for laparoscopic skills certification based on objective scoring, high availability, and lower cost. However, similar evaluation is lacking for robotic training. The purpose of this study was to assess several criteria, such as reliability, face, content, construct, and concurrent validity of a new virtual robotic surgery simulator.MethodsThis prospective study was conducted from December 2009 to April 2010 using three simulators dV-Trainers® (MIMIC Technologies®) and one Da Vinci S® (Intuitive Surgical®). Seventy-five subjects, divided into five groups according to their initial surgical training, were evaluated based on five representative exercises of robotic specific skills: 3D perception, clutching, visual force feedback, EndoWrist® manipulation, and camera control. Analysis was extracted from (1) questionnaires (realism and interest), (2) automatically generated data from simulators, and (3) subjective scoring by two experts of depersonalized videos of similar exercises with robot.ResultsFace and content validity were generally considered high (77xa0%). Five levels of ability were clearly identified by the simulator (ANOVA; pxa0=xa00.0024). There was a strong correlation between automatic data from dV-Trainer and subjective evaluation with robot (rxa0=xa00.822). Reliability of scoring was high (rxa0=xa00.851). The most relevant criteria were time and economy of motion. The most relevant exercises were Pick and Place and Ring and Rail.ConclusionsThe dV-Trainer® simulator proves to be a valid tool to assess basic skills of robotic surgery.

Ergonomic assessment of the surgeon's physical workload during standard and robotic assisted laparoscopic procedures.

Standard laparoscopy is responsible for musculoskeletal problems because of surgeons anti‐ergonomic positions. Robot‐assisted laparoscopy seems to reduce these musculoskeletal disorders thanks to the surgeons seated position. The objective of this study is to evaluate the muscular strain and cognitive stress induced by these two techniques during real operations conducted on the pig.

Epstein-Barr virus lymphoproliferative disease of donor origin after kidney transplantation: A case report

A case of an Epstein-Barr virus (EBV)-associated B lymphoproliferative disorder presented as a renal transplant obstruction is reported. The diagnosis was made from histology, immunohistochemistry, and EBV expression studies. Cytogenetic analysis showed the tumor to be of donor origin and revealed chromosomal translocation 46, XY, inv (1)(p35; q41), involving the EBV insertion site 1(1p35) and transforming growth factor beta 2(1q41) loci.

Subjective MPEG2 compressed video quality assessment: Application to Tele-surgery

The digital revolution in medical environment speeds up development of remote Robotic-Assisted Surgery and consequently the transmission of medical numerical data such as pictures or videos becomes possible. However, medical video transmission requires significant bandwidth and high compression ratios, only accessible with lossy compression. Therefore research effort has been focussed on video compression algorithms such as MPEG-2. In this paper, we are interested in determining compression thresholds and associated bit-rates which are acceptable with respect to the quality required in the field of medical video transmission. To evaluate MPEG-2 compressed medical video quality, we performed a subjective assessment test with a panel of human observers (experienced surgeons) using a DSCQS (Double-Stimuli Continuous Quality Scale) protocol derived from the International Telecommunication Union recommendations (ITU-R BT-500-11). Promising results estimate that 3 Mbits/s could be sufficient (compression ratio around threshold compression level around 90∶1 compared to the original 270 Mbits/s) as far as perceived quality is concerned.

Paradigms and experimental set-up for the determination of the acceptable delay in Telesurgery

The aim of this work was to develop an experimental set-up and realistic paradigms to study the effect of delay on video flux transmission and surgical performance. Four exercises were performed by 15 surgeons with 5 different simulated transmission delays. Large standard deviation of the duration of an exercise was found. Even with a short transmission delay of 150 ms, some surgeon found that the surgical procedure was not possible. Further work has to be done to have a better evaluation of the surgical precision.

A new system for evaluation of armrest use in robotic surgery and validation of a new ergonomic concept - armrest load.

The da Vinci robot provides a sitting position and an armrest to decrease workload and increase dexterity. We investigated the surgeons ergonomic behaviour by installing force sensors on the dV‐Trainer® simulators armrest to measure the armrest load during the performance of simulated exercises.

Pelvic magnetic resonance imaging angioanatomy of the arterial blood supply to the penis in suspected prostate cancer patients.

PURPOSEnTo describe the internal pudendal artery (IPA) and accessory pudendal artery (APA) detected by magnetic resonance (MR) angiography to help surgeons to find and preserve them during radical prostatectomy (RP).nnnMATERIALS AND METHODSnConstrast-enhanced MR 3.0 T angiography of the pelvis were performed in 111 male patients suspected diagnosis of prostate cancer (PCa), and describe the penile arterial blood supply.nnnRESULTSnThere are three patterns of the arterial blood supply to the penis (IPA and/or APA) accounting for 51.4%, 46.8% and 1.8% of cases, respectively. About the accessory pudendal artery (APA): 54/111 (48.6%) patients had APA with five different branching patterns, they were type I (APA bilateral symmetry): 17 (31.5%); type II (APA bilateral asymmetry): 1 (1.9%); type III (APA unilateral lateral): 13 (24%); type IV (APA unilateral apical): 21 (38.9%); type V (APA unilateral mix): 2 (3.7%). APA origin were from inferior epigastric artery (IEA): 7 (9.5%); from inferior vesical artery (IVA): 32 (43.2%); from obturator artery (OA): 35 (47.3%).nnnCONCLUSIONnA precise angioanatomic evalutation of arteries destined to the penis by MR angiography pre-operation for male pelvic organs will help surgeons to preserve them and contributes to reduce the erectile dysfunction after these procedures.

Determination of the chemical composition of human renal stones with MDCT: influence of the surrounding media

The selection of the optimal treatment method for urinary stones diseases depends on the chemical composition of the stone and its corresponding fragility. MDCT has become the most used modality to determine rapidly and accurately the presence of stones when evaluating urinary lithiasis treatment. That is why several studies have tempted to determine the chemical composition of the stones based on the stone X-ray attenuation in-vitro and invivo. However, in-vitro studies did not reproduce the normal abdominal wall and fat, making uncertain the standardization of the obtained values. The aim of this study is to obtain X-ray attenuation values (in Hounsfield Units) of the six more frequent types of human renal stones (n=217) and to analyze the influence of the surrounding media on these values. The stones were first placed in a jelly, which X-ray attenuation is similar to that of the human kidney (30 HU at 120 kV). They were then stuck on a grid, scanned in a water tank and finally scanned in the air. Significant differences in CT-attenuation values were obtained with the three different surrounding media (jelly, water, air). Furthermore there was an influence of the surrounding media and consequently discrepancies in determination of the chemical composition of the renal stones. Consequently, CT-attenuation values found in in-vitro studies cannot really be considered as a reference for the determination of the chemical composition except if the used phantom is an anthropomorphic one.

Degradation of the z- resolution due to a longitudinal motion with a 64-channel CT scanner

Isotropic acquisitions are routinely achievable with 64- channel CT scanners. As it predecessors, it includes multiplanar reformation (MPR) projection for the reconstruction of two-dimensional images and volume rendering for the creation of three dimensional images. The accuracy of images obtained with these postprocessing methods depends on the spatial resolution of image data acquired along the long axis of the patient (ie longitudinal, or z-axis spatial resolution). But physiologic motions can appear during a computed tomography (CT) exam and can lead to a degradation of this spatial resolution. By using two different phantoms and a dynamic platform, we have studied the influence of a z-axis linear motion on the MPR images quality. Our results show that the corruption of the data results in the loss of information about the form, the contrast and/or the size of the scanned object. This corruption of data can lead to diagnostic errors by mimicking diseases or by masking physiologic details.

Prior experience in micro-surgery may improve the surgeon's performance in robotic surgical training

Robotic surgery has witnessed a huge expansion. Robotic simulators have proved to be of major interest in training. Some authors have suggested that prior experience in micro‐surgery could improve robotic surgery training.