Health economics. Patients will be followed up for 2 years within this study. Key milestones will be assessed at 6 and 12 months. The follow-up regimen includes bronchoscopy and airway brushings taken at 1 week post implantation and full physical assessment including CT imaging, pulmonary function tests, blood tests and bronchoscopy at 1, 6, 12, 18 and 24 months. Telephone follow-up will take place in between these assessments.