Biodegradable stents, especially those composed of magnesium alloy-based materials, can provide a temporary scaffold that support vessels while naturally resorbing in the body after the targeted vessel heals, thereby preventing the restenosis and late thrombosis issues caused by their metallic predecessors. However, due to limitations in the intrinsic mechanical properties of magnesium, further investigation is required to optimize its degradation property, as well as the design, geometry and strut thickness to improve conformability in stent applications. This study aimed to investigate experimentally the degradation property of magnesium alloy WE43 and to optimize the stent geometry through parametric studies using the finite element method. Results of the degradation testing showed that the WE43 with a secondary polycaprolactone dip-coating offered a greater resistance to biodegradation and increased the lifespan of the stent. On average, the resistance to biodegradation increased by 5% in the WE43 magnesium alloy compared with its counterpart lacking any surface coating. The parametric studies have indicated that the stent with honeycomb geometry and a radial thickness of 0.15 mm had demonstrated promising mechanical performance with minimal dog-boning, foreshortening and recoil.

Stroke is the second most common cause of death and remains a persistent health challenge globally. Due to its highly time-sensitive nature, earlier stroke treatments should be enforced for improved patient outcome. The mobile stroke unit (MSU) was conceptualized and implemented to deliver the diagnosis and treatment to a stroke patient in the ultra-early time window (<1 h) in the pre-hospital setting and has shown to be clinically effective. However, due to geographical challenges, most rural communities are still unable to receive timely stroke intervention, as access to specialized stroke facilities for optimal stroke treatment poses a challenge. Therefore, the aircraft counterpart (Air-MSU) of the conventional road MSU offers a plausible solution to this shortcoming by expanding the catchment area for regional locations in Australia. The implementation of Air-MSU is currently hindered by several technical limitations, where current commercially available CT scanners are still oversized and too heavy to be integrated into a conventional helicopter emergency medical service (HEMS). In collaboration with the Australian Stroke Alliance and Melbourne Brain Centre, this article aims to explore the possibilities and methodologies in reducing the weight and, effectively, the size of an existing CT scanner, such that it can be retrofitted into the proposed search and rescue helicopter—Agusta Westland AW189. The result will be Australia’s first-ever customized CT scanner structure designed to fit in a search-and-rescue helicopter used for Air-MSU.