In some patients with chronic obstructive pulmonary disease (COPD) the breathlessness is caused by hyperinflation of the lungs. This causes difficulty breathing air out and makes it harder to breath in new air and limits the movement of the diaphram. The diaphragm is the muscle used for breathing between the chest and the stomach. Some of these patients can receive treatment with endobronchial valves, where one-ways are inserted into the bronchial system the let out some of the excess air, and thereby relieve breathlessness.

The goal of this observational study is to investigate the effect of endobronchial valves on the mobility of the diaphragm in patients with chronic obstructive pulmonary disease. The main questions it aims to answer are:

• If the movement of the diaphragm improves after treatment with endobronchial valves.
• If there is a link between improvement of diaphragm function and improvement of symptoms, lung function and physical ability.
• If ultrasound scan immediately after the treatment will predict which patients will benefit from the treatment.

Participants will undergo ultrasound before, 1 day after and 90 days after the procedure, and lung function examinations from their already planned control visits will be collected.

When emphysema is present in COPD-patients, the impaired expiratory ventilation causes lung hyperinflation. This results in a change in the respiratory mechanisms of the thorax and thereby impairment of the movement capacity of the muscles. The most important respiratory muscle, the diaphragm, is caudally displaced and flattened, hence, the capacity and mobility of the muscle decreases.

Some patients with COPD fulfill the criteria for treatment with endobronchial valves (EBV) where one-way valves can be inserted in the bronchial system. The mechanism behind the effect of EBV is believed to be formation of an atelectasis of the designated lobe and thereby reduction of hyperinflation and hence reduction of symptoms and increase in pulmonary function

In this study the aim is to assess:

1. If the movement of the diaphragm improves after insertion of endobronchial valves in patients with severe emphysema.
2. If there is a correlation between improvement of diaphragm function and improvement of symptoms, lung function examinations and physical ability after insertion of endobronchial valves.
3. If immediate post-procedural ultrasound evaluation of diaphragm function predicts the development of atelectasis and hence clinical outcome

Inclusion Criteria:

1. Patients selected to receive treatment with endobronchial valves
2. Signed informed consent

Exclusion Criteria:

1. Neuromuscular disease interfering with diaphragm function
2. Pleural effusion at time of preoperative or 90-days postoperative ultrasound

Patients with COPD approved for treatment with endobronchial valves. The suitability will be assessed during multidiciplinary team conference, independent of this study.