Abstract：
The nasal administration of therapeutic fluids and vaccines is used to treat allergic rhinitis, sinusitis, congestion, coronaviruses and even Alzheimer\'s disease. In the latter, the drug must reach the olfactory region, so it finds its way into the central nervous system. Effective administration techniques able to reach the olfactory region are challenging due to the tortuous anatomy of the nasal cavity, and are frequently evaluated in vitro using transparent anatomical models. Here, the liquid distribution inside a 3D printed human nasal cavity is quantified for model fluids resulting from the discharge of a 1-mL syringe with either a spray-generating nozzle, and a straight tip emitting a collimated fluid stream. Experiments using two model fluids with different viscosities suggest that a simple, correctly positioned straight tip attached to a syringe is able to efficiently deliver most of a therapeutic fluid in the human olfactory region in the side-laying position, avoiding the adoption of head-back and head-down positions that can be difficult for patients in the age range typical of Alzheimer\'s disease. Furthermore, we demonstrate by computer simulations that the conclusion is valid within a wide range of parameters.
摘要：
治疗性液体和疫苗的鼻给药用于治疗过敏性鼻炎，鼻窦炎,拥塞，冠状病毒甚至阿尔茨海默病。在后者中,药物必须到达嗅觉区域，所以它进入了中枢神经系统。由于鼻腔的曲折解剖结构，能够到达嗅觉区域的有效给药技术具有挑战性。并且经常使用透明解剖模型在体外进行评估。这里,3D打印人鼻腔内的液体分布被量化为模型流体，该模型流体是由带有喷雾生成喷嘴的1-mL注射器排出而产生的，和发射准直流体流的直尖端。使用两种具有不同粘度的模型流体的实验表明，正确定位的直尖端连接到注射器能够有效地输送大部分的治疗流体在人体嗅觉区域在侧躺位置，避免采用头靠和头靠下的位置，这对于典型的阿尔茨海默病年龄范围内的患者来说是困难的。此外，我们通过计算机模拟证明了结论在很宽的参数范围内是有效的。
