The purpose of this study is to assess efficiency and safety of cryobiopsy compared to video-assisted thoracoscopic lung biopsy (VATS) in diagnosis of interstitial lung diseases (ILD). To that end, this non-interventional study prospectively collects data from patients undergoing routine diagnosis of ILD. In some of those patients less invasive diagnostic approaches do not yield a definitive diagnosis. Thus, they will ultimately be subjected to VATS if this procedure is reasonable. The information gained by this study will help to assess the significance of cryobiopsy in contrast to VATS in this particular disease group.

Inclusion Criteria:

• Age ≥ 18 years
• Known or newly diagnosed interstitial lung disease (ILD)
• Indication for lung biopsy for definitive ILD diagnosis
• Informed Consent provided

Exclusion Criteria:

• Age < 18 years
• Inability or contraindication to undergo any form of invasive diagnostic procedure associated with diagnosis of interstitial lung disease
• Severely restricted CO diffusion capacity (<50%)
• Pregnancy, lactation
• Any medical, psychological or other condition restricting the patient's ability to provide informed consent
• Participation in another clinical trial

Inpatients undergoing routine diagnosis of known or suspected interstitial lung disease