Robot-assisted image-guided transcranial magnetic stimulation for somatotopic mapping of the motor cortex: a clinical pilot study

Shape and exact location of motor cortical areas varies among individuals. The exact knowledge of these locations is crucial for planning of neurosurgical procedures. In this study, we have used robot-assisted image-guided transcranial magnetic stimulation (Ri-TMS) to elicit MEP response recorded for individual muscles and reconstruct functional motor maps of the primary motor cortex

Connectivity-Guided Theta Burst Transcranial Magnetic Stimulation Versus Repetitive Transcranial Magnetic Stimulation for Treatment-Resistant Moderate to Severe Depression: Magnetic Resonance Imaging Protocol and SARS-CoV-2–Induced Changes for a Randomized Double-blind Controlled Trial

Background:Depression is a significant health and economic burden. In approximately one third of patients, depression is resistant to first line treatments and therefore it is essential that alternative treatments are found. Transcranial magnetic stimulation (TMS) is a neuromodulatory treatment involving the application of magnetic pulses to the brain that is approved in the UK and the US in treatment resistant depression. This trial aims to compare the clinical effectiveness, cost-effectiveness and mechanism of action between standard treatment repetitive TMS (rTMS) targeted at the F3 EEG site, with a newer treatment – a type of TMS called theta-burst stimulation (TBS) targeted based on measures of functional brain connectivity. This protocol outlines the brain imaging acquisition and analysis for the BRIGhTMIND trial that is used to create personalised TMS targets and answer the proposed mechanistic hypotheses.Objective:The objectives of the imaging arm of the BRIGhTMIND study are to identify functional and neurochemical brain signatures indexing the treatment mechanisms of rTMS and cgiTBS and to identify imaging-based markers predicting response to treatment.Methods:The study is a randomised double-blind controlled trial with 1:1 allocation to either 20 sessions of a) TBS or b) standard rTMS. Multimodal magnetic resonance imaging (MRI) is acquired per participant at baseline (prior to TMS treatment) with T1-weighted and task-free functional MRI during rest (rsfMRI) utilised to estimate TMS targets. For participants enrolled in the mechanistic substudy additional diffusion-weighted, sequences are acquired at baseline and at post-treatment follow-up 16 weeks after treatment randomisation. Core datasets of T1-weighted and task-free functional MRI during rest (rsfMRI) are acquired for all participants and utilised to estimate TMS targets. Additional sequences of arterial spin labelling, magnetic resonance spectroscopy and diffusion-weighted images are acquired dependent on recruitment site for mechanistic evaluation. Standard rTMS treatment is targeted at the F3 electrode site over the left dorsolateral prefrontal cortex whilst TBS treatment is guided using the coordinate of peak effective connectivity from the right anterior insula to the left dorsolateral prefrontal cortex. Both treatment targets benefit from a level of MRI-guidance but only TBS is provided with precision targeting based on functional brain connectivity.Results:Recruitment began January 2019 and is ongoing. Data collection is expected to continue until January 2023.Conclusions:This trial will determine the impact of precision MRI guidance on rTMS treatment, and furthermore, assess the neural mechanisms underlying this treatment in treatment resistant depressed patients. Clinical Trial: International Standard Randomized Controlled Trial Number (ISRCTN) 19674644; https://www.isrctn.com/ISRCTN19674644. Registered 2nd October 2018

A Robotic C-arm Fluoroscope

Fluoroscopic C-arms are common devices for acquiring images during surgery. Manual positioning is timeconsuming and requires considerable experience. Trained users must often take several images to find the best viewing direction. If a second image must be taken from the same position, e.g. for post operative control, the Carm must be moved to the exact same position. Without guidance, this is often difficult to accomplish. We developed the idea to completely “robotize ” a standard C-arm, i. e. to equip all joints with motors and encoders. A software environment provides for intelligent control. To archive this goal a complete kinematic analysis of the fluoroscope was necessary. On the basis of this analysis a number of clinical applications have been developed: (1) simplified positioning via cartesian control; (2) automatic acquisition of panoramic images; (3) 3D CT with arbitrary viewing angles; (4) 4D intraoperative CT with/without respiration triggering; (5) automated anatomy-oriented positioning. The goal of this research is thus three-fold: Minimize radiation exposure of the OR staff, reduce positioning time and offer enhanced imaging capability. Keywords: Robot-assisted surgery, medical robotics, intra-surgical imaging, robotized C-arm, 3D flouroscope, C-arm kinematics I

Protected complex percutaneous coronary intervention and transcatheter aortic valve replacement using extracorporeal membrane oxygenation in a high-risk frail patient: a case report

Background Transcatheter aortic valve replacement has become a routine procedure for patients with severe symptomatic aortic stenosis at increased surgical risk. Not much is known about using prophylactic support with venoarterial extracorporeal membrane oxygenation in patients undergoing transcatheter aortic valve replacement and eventually concomitant complex percutaneous coronary intervention. Case presentation We present a successful procedure of transcatheter aortic valve replacement and high-risk percutaneous coronary intervention utilizing venoarterial extracorporeal membrane oxygenation for hemodynamic support in a very frail 88-year-old Caucasian woman with severe symptomatic aortic stenosis and coronary bypass grafting in the past. Echocardiography revealed a “low-flow low-gradient” aortic stenosis (mean transvalvular gradient 30 mmHg, aortic valve area 0.4 cm2, significant calcification), a left ventricular ejection fraction of 35%, severe mitral regurgitation with moderate stenosis (mean transvalvular gradient 7 mmHg), with a systolic pulmonary artery pressure of 80 mmHg. Moreover, pre-interventional coronary angiography exposed a severe left main ostial stenosis and sequential subtotal heavily calcified stenosis of the left anterior descending artery . Computed tomographic angiography showed no heavy tortuosity but moderate calcification of the iliofemoral arteries. The procedure was performed under general anesthesia in our hybrid operating room. Extracorporeal membrane oxygenation was established by left femoral percutaneous cannulation using a 21-Fr venous and 15-Fr arterial cannula. Subsequently, complex percutaneous coronary intervention with implantation of two drug-eluting stents from the left main into the left anterior descending artery was performed via a right femoral arterial 7F sheath. Thereafter, a 23-mm Sapien 3 aortic valve prosthesis (Edwards, Irvine, CA, USA) was implanted via right femoral artery in the usual manner, whereby the arterial pigtail catheter for marking the aortic annulus during transcatheter aortic valve replacement was inserted over a Check-Flo® Hemostasis Assembly (Cook Medical, Bloomington, IN, USA) on a Y-adapter via the arterial extracorporeal membrane oxygenation cannula. After extracorporeal membrane oxygenation decannulation, vascular closure was easily performed using the MANTA vascular closure device in order to reduce procedural time and risk of access site complications. Conclusions In summary, we demonstrate the feasibility of elective prophylactic extracorporeal membrane oxygenation implementation in selected very high-risk and frail patients undergoing transcatheter aortic valve replacement and percutaneous coronary intervention in order to avoid intraprocedural complications