Application of ultrasound-guided medical thoracoscopy in patients with small amounts or without pleural effusion.

"Declarations Ethical approval and consent to ParticipateThis study was approved by the Biomedical Ethics Review Committee of West China Hospital of Sichuan University. The informed consent was waived by the Biomedical Ethics Review Committee of West China Hospital of Sichuan University. Other contributionsWe would like to thank staff assisting with thoracoscopy, such as Yue Cheng, and the respiratory staff for their help and support of our study. Consent for publicationNot applicable. Competing interestsThe authors declare no competing interests. Competing interests The authors declare no competing interests."

"Funding This work was supported by the National Natural Science Foundation of China (grant number 82173182) and Sichuan University West China Hospital Clinical Incubation 1.3.5 Project (2022HXFH002)."