In-Vivo Validation of a Novel Robotic Platform for Endovascular Intervention.

OBJECTIVE: In-vivo validation on animal setting of a pneumatically propelled robot for endovascular intervention, to determine safety and clinical advantage of robotic cannulations compared to manual operation. METHODS: Robotic assistance and image-guided intervention are increasingly used for improving endovascular procedures with enhanced navigation dexterity and accuracy. However, most platforms developed in the past decade still present inherent limitations in terms of altered clinical workflow, counterintuitive human-robot interaction, and a lack of versatility. We have created a versatile, highly integrated platform for robot-assisted endovascular intervention aimed at addressing such limitations, and here we demonstrate its clinical usability through in-vivo animal trials. A detailed in-vivo study on four porcine models conducted with our robotic platform is reported, involving cannulation and balloon angioplasty of five target arteries. RESULTS: The trials showed a 100% success rate, and post-mortem histopathological assessment demonstrated a reduction in the incidence and severity of vessel trauma with robotic navigation versus manual manipulation. CONCLUSION: In-vivo experiments demonstrated that the applicability of our robotic system within the context of this study was well tolerated, with good feasibility, and low risk profile. Comparable results were observed with robotics and manual cannulation, with clinical outcome potentially in favor of robotics. SIGNIFICANCE: This study showed that the proposed robotic platform can potentially improve the execution of endovascular procedures, paving the way for clinical translation.

An MR-Safe Endovascular Robotic Platform: Design, Control, and Ex-Vivo Evaluation.

OBJECTIVE: Cardiovascular diseases are the most common cause of global death. Endovascular interventions, in combination with advanced imaging technologies, are promising approaches for minimally invasive diagnosis and therapy. More recently, teleoperated robotic platforms target improved manipulation accuracy, stabilisation of instruments in the vasculature, and reduction of patient recovery times. However, benefits of recent platforms are undermined by a lack of haptics and residual patient exposure to ionising radiation. The purpose of this research was to design, implement, and evaluate a novel endovascular robotic platform, which accommodates emerging non-ionising magnetic resonance imaging (MRI). METHODS: We proposed a pneumatically actuated MR-safe teleoperation platform to manipulate endovascular instrumentation remotely and to provide operators with haptic feedback for endovascular tasks. The platform task performance was evaluated in an ex vivo cannulation study with clinical experts ( N = 7) under fluoroscopic guidance and haptic assistance on abdominal and thoracic phantoms. RESULTS: The study demonstrated that the robotic dexterity involving pneumatic actuation concepts enabled successful remote cannulation of different vascular anatomies with success rates of 90%-100%. Compared to manual cannulation, slightly lower interaction forces between instrumentation and phantoms were measured for specific tasks. The maximum robotic interaction forces did not exceed 3N. CONCLUSION: This research demonstrates a promising versatile robotic technology for remote manipulation of endovascular instrumentation in MR environments. SIGNIFICANCE: The results pave the way for clinical translation with device deployment to endovascular interventions using non-ionising real-time 3D MR guidance.

Utility of Culturing Marginal Bone in Patients Undergoing Lower Limb Amputation for Infection.

Guidelines suggest culturing clinically uninfected bone at the margin after surgical resection for osteomyelitis, but little published evidence supports this procedure. To investigate whether culturing marginal bone after completing resection of infected bone affected antibiotic use or further surgical intervention, we collected data on sequential patients undergoing amputation for a foot infection at our tertiary care hospital between January 2014 and May 2015. We recorded patient age, sex, presence of diabetes mellitus, level of amputation, whether marginal bone was sent for culture, microbiology of any marginal bone specimens, type and duration of antibiotic therapy, and any further surgical resection. Among 132 patients, the mean age was 71.9 years, 103 (78.0%) were male, and 79 (59.8%) had diabetes. Treating surgeons sent marginal bone in 58 (43.9%) of these patients, 50 (86.2%) of which were culture positive. Patients with a positive bone culture were significantly more likely to undergo further surgical intervention (20.0% vs 6.1%, p = .047). For patients with diabetes, compared with those without, surgeons did not send marginal bone for culture more often (46% vs 42%, p = .72), nor did they undertake further surgical interventions more frequently (13.4% vs 10.1%, p = .89). Our results suggest that the clinicians used the marginal bone culture findings to make clinical decisions but do not clarify if there is a benefit to performing this procedure. Although patients whose proximal bone specimens were culture positive were more likely to undergo a surgical intervention, the reasons for, and benefit of, this additional surgery were unclear.

Medium-term outcomes of fenestrated endovascular repair of juxtarenal abdominal aortic aneurysms.

BACKGROUND: Abdominal aortic aneurysms pose a substantial clinical burden, and a significant proportion are not anatomically suitable for open repair or standard endovascular aneurysm repair (EVAR), instead requiring fenestrated EVAR (fEVAR). We sought to compare clinical outcomes and trends over time in patients undergoing fEVAR in Australia. METHODS: We conducted a retrospective analysis of all patients undergoing fEVAR at a tertiary referral centre between 2010 and 2015, including outcomes and complications, both as inpatients and after discharge. RESULTS: Thirty-nine patients underwent fEVAR during the study period, with mean age of 75 years and mean aneurysm size of 61 mm. One hundred and thirty-four target vessels were treated and inhospital mortality was 5% (two patients). There were nine inhospital, eight Type II and one Type III endoleaks. Ten patients suffered acute kidney injury, one of whom required dialysis. Mean follow-up was 14.5 months (range: 0-46.7). Target vessel patency was 99.2% at follow-up. There were six Type II endoleaks at follow-up, and two patients died during the follow-up period (of non-aneurysm-related causes). CONCLUSION: fEVAR is an effective treatment with low morbidity and mortality, and we have demonstrated excellent survival and target vessel patency at a mean follow-up of 14 months. Endoleak rates were low, despite the high complexity of the aneurysms treated.

YouTube as a source of patient information for varicose vein treatment options.

OBJECTIVE: The purpose of this study was to analyze the quality of content and potential sources of bias in videos available on YouTube pertaining to interventional treatment for varicose veins. METHODS: Searches were performed on YouTube to identify videos pertaining to interventional treatment for varicose veins. Videos that met eligibility criteria were analyzed and rated according to predetermined criteria by two independent assessors, with a third independent assessor to resolve any discrepancy. Each video was rated for its informational quality (good, fair, poor) and stance (for, neutral, against, unclear) toward the treatment option discussed. RESULTS: A total of 284 videos were extracted, of which 228 met eligibility criteria and were analyzed. The largest group of videos (47.3%) received a quality rating of fair, meaning that they discussed one or two aspects of a treatment option, such as procedural technique and indications. Among those videos rated poor (25.0%), nearly all videos (98.2%) failed to mention a specific treatment. Most videos (71.1%) were in favor of the treatment discussed without presenting balanced discussion of alternatives. Private companies represented the most frequent source of videos analyzed (73.2%). There was a statistically significant correlation between quality and video source (χ2 = 9.308; df = 2; P = .010), with videos from private companies generally receiving poorer quality ratings than other videos. There was no association between quality and viewing frequency of videos (P = .379). CONCLUSIONS: On the whole, the videos available on YouTube are neither sufficiently comprehensive nor adequately balanced to be recommended as patient education material regarding interventional treatment options for varicose veins.

A simple technique to prevent torsion and other obstructions of autogenous vein conduits.

During a bypass or a transposed fistula, there is a risk of twisting or torsion of the vein within the tunnel, which may not be easily apparent when incomplete. When valvulotomes are used some nonobstructing leaflets or flaps may remain. These mechanical problems may go undetected at the time and may cause hemodynamic changes, act as a nucleus for thrombosis, or obstruction postoperatively. These may result in early graft failure. A simple technique to prevent and treat twisting and other obstructions in autogenous venous conduits is described. Use of this method has helped the authors to avoid acute obstructions in vein bypasses and transposed dialysis access fistulas.

The influence of crowds on consumer health decisions: an online prospective study.

This paper presents an online prospective study investigating whether the strength of social feedback, i.e. the proportion of persons who concur or do not concur with one's own answer to a question, influences the way one answers health-related questions. Two hundred and twenty-seven undergraduate students were recruited to use an online search engine to answer six health-related questions. Subjects recorded their pre- and post-search answers to each question and their level of confidence in these answers. After answering each question post-search, subjects were presented with a summary of post-search answers provided by previous subjects and were asked to answer the question again. There was a statistically significant relationship between the absolute number of others with a different answer (the crowd's opinion volume) and the likelihood of an individual changing an answer (P<.0001). Subjects' likelihood of changing answer increased as the percentage of others with a different answer (the crowd's opinion density) increased (P=0.047). Overall, 98.3% of subjects did not change their answer when it concurred with the majority (i.e. >50%) of subjects. When subjects had a post-search answer that did not concur with the majority, they were 24% more likely to change answer than those with answers that concurred (P<.0001). This study provides empirical evidence that strength of social feedback influences the way healthcare consumers answer health-related questions.