Intratracheal delivery of nano- and microparticles and hyperpolarized gases: a promising strategy for imaging and treatment of respiratory disease.

Accurate diagnosis is crucial for improving treatment and prognosis of respiratory disease, especially lung cancer. Tumors and lesions located deep in the lung are directly accessible via dendritic tracheal bronchus, thereby opening a new way to tackle respiratory disease. Intratracheal delivery is an innovative noninvasive approach for imaging and treating respiratory disease efficiently, when compared to other delivery methods. Intratracheal delivery of nano- and microparticles and hyperpolarized gases offers valuable clinical advantages, such as assessing lung function, monitoring ventilation and perfusion, controlling disease progression and inhibiting tumor growth. Especially, versatile nano-sized particles have enormous potential to benefit precision imaging and therapy at molecular level. Here we discuss the recent advances in intratracheal delivery of nano- and microparticle approaches and hyperpolarized gases for respiratory disease imaging and treatment, with an emphasis on intratracheal nanoparticles delivery of pulmonary imaging, which has extremely valuable clinical applications in precise theranostic for respiratory disease.