Abstract
Robot-assisted thymothymectomy with 1 subxiphoid and 3 intercostal ports provides high maneuverability around the upper poles of the thymus and excellent visualization of the superior sections of the phrenic nerves. However, it limits the visibility of the inferior sections of the phrenic nerves and hinders maneuverability around the pericardiophrenic angle in cases of extended thymothymectomy. This report describes the "lateral view preceding method" that successfully uses bilateral thoracoscopy to dissect the lower poles of the thymus and mediastinal fat around the pericardiophrenic angle, followed by robot-assisted thymothymectomy to remove the upper poles of the thymus.