Analysis of the anatomic changes in the thoracic cage after a lung resection using magnetic resonance imaging

The thoracic cage after a lung resection is filled by the remaining lobes, the elevated diaphragm, the diminished thoracic cage, and by mediastinal sh ifting. The changes in the thorax after a lung resection were quantified us ing magnetic resonance imaging. The study group consisted of 39 patients wh o had undergone a lobectomy, four who had undergone a pneumonectomy, and 14 controls. The left ventricular angle, ascending aortic angle, mediastinal shift, longitudinal length of the thoracic cage, the distance between the t horacic apex and the level of the aortic valve, and diaphragmatic elevation were all measured. After a right lower lobectomy, the mediastinum shifted more rightward than after a right upper lobectomy. The diaphragm became mor e greatly elevated after a right upper lobectomy than after a right lower l obectomy. When a chest wall resection was added to a right upper lobectomy, the mediastinal anatomical changes decreased. After a left upper lobectomy , the degree of mediastinal shifting was greater than after a left lower lo bectomy. A left upper lobectomy shifted the mediastinum at the level of the right atrium. This method is easily reproducible and was found to be effec tive for quantifying the changes in the thorax after a lung resection.