Significance of follow‐up thoracic imaging in myasthenia gravis

Abstract

Objectives Most patients with myasthenia gravis (MG) undergo thoracic imaging at initial diagnosis. However, the follow‐up protocol is unclear. The objective of the present study was to clarify the follow‐up status and main findings of thoracic imaging in patients with MG. Methods A total of 649 patients with disease duration ≥1 year were included in the study. The follow‐up rate and time from the initial scan to the latest thoracic imaging were evaluated. The rate of abnormality and details of abnormal findings in both non‐thymomatous MG and thymoma‐associated MG were investigated. Results The follow‐up thoracic imaging rate of 145 patients with thymoma‐associated MG was 71.7%, whereas just 46.2% of 504 patients with non‐thymomatous MG underwent follow‐up imaging. Abnormal findings were detected in 8.6% of patients with non‐thymomatous MG and 26.0% of those with thymoma‐associated MG. Abnormal findings included cancer, lung infection and lymph node swelling in the former, and relapse or increased size of thymoma in the latter. Conclusions Frequent follow up by thoracic imaging is necessary in patients with MG.