Improving the longevity of oesophageal stents

英国癌症研究中心介绍，2017年每年新增食道癌病例9200例。70%的人在晚期确诊，无法治愈，每年造成7925人死亡。近年来，使用化疗和放射治疗--以及最近的激素治疗--的治疗提高了患者的存活率，将支架患者接受支架后的存活期从2004年的平均3个月延长到目前的15-18个月。大多数食道癌发病较晚，无法治愈，大多数患者最终需要插入支架(最常见的是镍钛合金支架)以保留食管腔，并允许患者继续进食。这些支架最初设计用于血管，但已被改装用于胃肠道和食道，因此使支架在不同的工作环境下工作，特别是由于暴露在低pH值的胃酸下，但由于食道功能(蠕动)的移动和压缩，支架也受到机械作用。因此，越来越多的患者经历了设备故障，需要重复操作。6个月后的再干预率达到60%，导致支架失败率增加，需要进行进一步的手术，使患者面临更大的风险。通过改善这些镍钛合金支架的性能，我们可以延长它们的使用寿命，消除移除和更换的需要。这将改善临床结果和患者体验，并减少重复程序的需要和NHS的相关成本。

Cancer Research UK describes 9,200 new cases of oesophageal cancer per year in 2017. 70% are diagnosed at a late stage, being incurable and causing 7,925 deaths / year. Treatments using chemotherapy and radiotherapy - and more recently hormone therapy - have improved patient survival in recent years, extending survival of stent patients after receiving a stent from an average of 3months in 2004 to currently 15-18months. Most oesophageal cancers present late and are not curable and most patients eventually require insertion of a stent (most commonly a nitinol stent) to keep the lumen of the oesophagus and allow the patient to continue to eat. These stents were originally designed for use in blood vessels but have been adapted for use in the gastro-intestinal tract and oesophagus therefore subjecting the stents to a different working environment especially chemical, due to exposure of the low pH of gastric acid, but also mechanical due to the movement and compression of oesophageal function (peristalsis). As a consequence an increasing number of patients experience device failure, requiring repeat procedures. The re-intervention rate at 6months reaches 60%, which is now resulting in increased stent failures, which necessitate further procedures, and puts the patient at additional risk.By improving the properties of these nitinol stents, we can improve their working life and remove the need for removal and replacement. This will improve clinical outcome and patient experience and reduce the need for repeat procedures and the associated costs to the NHS.