Current clinical approaches for treating pancreatic cancer have been demonstrated as ineffective at improving midterm survival. A primary obstacle to local drug delivery is the desmoplastic nature of the peritumoral environment, which acts as a significant barrier to circulating macromolecules. To address this need, our group presents a sharp fiberoptic microcatheter capable of accessing the pancreas through transduodenal endoscope and penetrating a tumor to locally co-deliver photothermal and fluid-based therapies. Experiments sought to characterize the mechanical penetration capabilities and fluid mechanics of the fiberoptic microneedle design. A refined off-center fusion splicing technique was developed for joining a multimode fiber to the annular core of a light-guiding capillary, allowing light transmission with minimal optical loss. A novel and frugal technique for assessing the penetration force of the microneedle was conducted in a bovine gelatin tissue phantom with a Young's modulus stiffer than the high range for pancratic tissue or tumor. Buckling forces for different microneedle lengths were measured and compared against theoretical values obtained from Euler's Critical Load equation under fixed-pinned column conditions. Hydraulic resistance of different capillary lengths was evaluated and compared against the theoretical values from Hagen-Poiseuille's law, allowing assessment of contributions from different segments of the device. The results demonstrated that the microcatheter can robustly and repeatably penetrate a soft tissue phantom chosen to be a conservative model of pancreatic tissue for penetration properties. Experiments showed that a 1.5 N insertion force was required for phantom penetration with a 45° beveled needle at a 5 mm unsupported length, while the critical buckling load was measured to be approximately 4 N. In addition, the design was demonstrated to efficiently transport 1064 nm light and aqueous fluids with a 70–75% light coupling efficiency and 12,200 Pa.s/μl hydraulic resistance, respectively. These findings motivate the FMD's further development as a treatment platform for pancreatic cancer.

已经证明，目前治疗胰腺癌的临床方法在改善中期生存方面无效。局部药物递送的主要障碍是肿瘤周围环境的减赘生性质，其是循环大分子的重要障碍。为了满足这一需求，我们的小组提出了一种锋利的光纤微导管，该导管能够通过十二指肠内窥镜进入胰腺并穿透肿瘤以局部共同提供光热疗法和液体疗法。实验试图表征光纤微针设计的机械穿透能力和流体力学。开发了一种改进的偏心熔接技术，用于将多模光纤连接到导光毛细管的环形纤芯，从而以最小的光学损耗实现光传输。在牛明胶组织体模中进行了一种新颖而节俭的评估微针穿透力的技术，该模型的杨氏模量比胰腺组织或肿瘤的高模量高。测量了不同长度的微针的屈曲力，并将其与在固定销柱条件下从欧拉临界载荷方程获得的理论值进行比较。评估了不同毛细管长度的水力阻力，并将其与Hagen-Poiseuille定律的理论值进行了比较，从而可以评估设备不同部分的贡献。结果表明，微导管可以牢固且可重复地穿透软组织体模，该体模被选为胰腺组织的保守模型，具有穿透特性。实验表明1。使用45°斜角针在5mm无支撑的长度上进行幻影穿透需要5 N的插入力，而测得的临界屈曲载荷约为4N。此外，该设计被证明可以有效地传输1064 nm的光和水流体的光耦合效率为70–75％，液压阻力为12,200 Pa.s /μl。这些发现激发了FMD作为胰腺癌治疗平台的进一步发展。