A new very-small-bore Simmons guiding sheath for transradial neurointervention: Technical note and initial experience

•Transradial cannulation into the left CCA can be challenging because of the lack of catheter support in the aortic arch.•Moreover, the use of large sheaths can increase the risk of access-site complications which can result in TRA failure and/or serious adverse events.•We developed a new very-small-bore transradial catheter system using a 3F Simmons guiding sheath for neurointervention.•This system can represent a useful treatment option for neurointervention, even in challenging cases.•Furthermore, this method may expand the indications for TRA. Transradial access during neurointerventions has increased in popularity because of reduced complications and patient preference. Nevertheless, transradial cannulation into the left common carotid artery can be difficult technically because of the lack of catheter support in the aortic arch. Furthermore, the use of large sheaths can increase the risk of complications at the access site. Here, we developed a new very-small-bore transradial system using a 3F Simmons guiding sheath, to increase the procedural success rate and minimize access-site complications. This system can represent a valuable treatment option for neurointerventions and has the potential to expand the indications for transradial access.