Evaluation of robotic endovascular catheters for arch vessel cannulation

Emerging technologies for image guidance and device navigation in interventional radiology

Recent developments in image-guidance and device navigation, along with emerging robotic technologies, are rapidly transforming the landscape of interventional radiology (IR). Future state-of-the-art IR procedures may include real-time three-dimensional imaging that is capable of visualizing the target organ, interventional tools, and surrounding anatomy with high spatial and temporal resolution. Remote device actuation is becoming a reality with the introduction of novel magnetic-field enabled instruments and remote robotic steering systems. Robots offer several degrees of freedom and unprecedented accuracy, stability, and dexterity during device navigation, propulsion, and actuation. Optimization of tracking and navigation of interventional tools inside the human body will be critical in converting IR suites into the minimally invasive operating theaters of the future with increased safety and unsurpassed therapeutic efficacy. In the not too distant future, individual image guidance modalities and device tracking methods could merge into autonomous, multimodality, multiparametric platforms that offer real-time data of anatomy, morphology, function, and metabolism along with on-the-fly computational modeling and remote robotic actuation. The authors provide a concise overview of the latest developments in image guidance and device navigation, while critically envisioning what the future might hold for 2020 IR procedures.

Tortuous iliac systems--a significant burden to conventional cannulation in the visceral segment: is there a role for robotic catheter technology?

PURPOSE

To attempt to quantify the effect of varying degrees of iliac tortuosity on maneuverability and "torquability" of endovascular catheters in the visceral segment, comparing conventional and robotic cannulation techniques.

MATERIALS AND METHODS

In a fenestrated endograft within a pulsatile phantom, 10 experienced operators cannulated the renal arteries via three different access vessels of varying iliac tortuosity with the use of conventional and robotic techniques. All procedures were performed in the angiography suite and recorded for blinded video assessment for quantitative (time, catheter-tip movements) and qualitative metrics (operator performance scores).

RESULTS

In total, 120 cannulations were observed. With increasing iliac tortuosity, median time and number of catheter movements required for renal cannulation with conventional techniques increased in stepwise fashion for mild, moderate, and severe iliac tortuosity (times, 7.6 min [interquartile range (IQR), 4.6-9.3 min] vs 6.9 min [4.2-11.4 min] vs 17.7 min [13.3-22.6 min], respectively; movements, 184 [IQR, 110-351] vs 251 [207-395] vs 569 [409-616], respectively). Median renal cannulation times were significantly reduced with the use of the robotic system irrespective of mild, moderate, or severe tortuosity (times, 1.4 min [IQR, 1.1-1.9 min] vs 3 min [2.3-3.3 min] vs 2.8 min [1.5-3.9 min], respectively; movements, 19 [IQR, 14-27] vs 46 [43-58] vs 45 [40-66], respectively; P < .005). Overall operator performance scores improved significantly with the use of the robotic system irrespective of iliac tortuosity severity.

CONCLUSIONS

In cases of moderate to severe iliac tortuosity, conventional catheter manipulation and control becomes an issue. The improvement in positional control and predictability seen with advanced catheter designs may be amplified in cases of severe iliac tortuosity.

Robotics and imaging in congenital heart surgery

The initial success seen in adult cardiac surgery with the application of available robotic systems has not been realized as broadly in pediatric cardiac surgery. The main obstacles include extended set-up time and complexity of the procedures, as well as the large size of the instruments with respect to the size of the child. Moreover, while the main advantage of robotic systems is the ability to minimize incision size, for intracardiac repairs, cardiopulmonary bypass is still required. Catheter-based interventions, on the other hand, have expanded rapidly in both application as well as the complexity of procedures and lesions being treated. However, despite the development of sophisticated devices, robotic systems to aid catheter procedures have not been commonly applied in children. In this article, we describe new catheter-like robotic delivery platforms, which facilitate safe navigation and enable complex repairs, such as tissue approximation and fixation, and tissue removal, inside the beating heart. Additional features including the tracking of rapidly moving tissue targets and novel imaging approaches are described, along with a discussion of future prospects for steerable robotic systems.

Risk of wound hematoma at carotid endarterectomy under dual antiplatelet therapy

BACKGROUND AND PURPOSE

This study aims to assess perioperative incidence of wound hematoma and bleeding in patients who underwent carotid endarterectomy (CEA) under dual antiplatelet therapy.

METHODS

Consecutive patients with initial CEA receiving aspirin, clopidogrel, or a combination of both were subjected to standard patch endarterectomy. Postoperative wound hematoma was assessed as moderate (subcutaneous bleeding, nonspace-occupying hematoma, and oozing suture bleeding) or severe, i.e., needing operative re-exploration.

RESULTS

Six hundred eighty-four (80.9%) patients with one of the three types of antiplatelet therapy out of 844 patients registered from 1995 to 2010 were enrolled. Wound hematoma occurred in 27 of 112 (24.1%) patients under combined aspirin and clopidogrel, 33 of 162 (20.4%) under clopidogrel, and 48 of 410 (11.7 %) under aspirin. Relative risk compared to aspirin was 2.4 (95% CI, 1.4 to 4.1) for aspirin and clopidogrel and 1.9 (95% CI, 1.2 to 3.1) for clopidogrel. Severe space-occupying hematoma needing operative re-exploration occurred in four (3.6%) patients under aspirin and clopidogrel, seven (4.3%) under clopidogrel, and five (1.2%) under aspirin. Corresponding relative risks were 3.0 (95% CI, 0.8 to 11.4) for aspirin and clopidogrel and 3.7 (95% CI, 1.1 to 11.7) for clopidogrel. Relative risks remained without relevant change after adjustment for potentially confounding variables.

CONCLUSIONS

Dual antiplatelet therapy with combined aspirin and clopidogrel as well as clopidogrel is associated with an increased incidence of perioperative wound hematoma compared to aspirin but on an acceptable low level of incidence. The latter may be achieved by adapting operative procedures to more intensive antiplatelet regimes.