Longitudinal Study of Helium-3 and Xenon-129 Magnetic Resonance Imaging

Who May Qualify: - Subjects male and female aged 50-85 with either A) a clinical diagnosis of COPD or Bronchiectais or B) \>10 pack/year smoking history - Subject understands the study procedures and is willing to participate in the study as indicated by signature on the willing to sign a consent form - Subject must be able to perform a breathhold for 16s. - Subject is judged to be in otherwise stable health on the basis of medical history - Subject is ambulatory and can perform the 6MWT - Subject able to perform reproducible pulmonary function testing (i.e., the 3 best acceptable spirograms have FEV1 values that do not vary more than 5% of the largest value or more than 100 ml, whichever is greater.) - FEV1 \>25% predicted - FVC \> 25% predicted and \>0.5L Who Should NOT Join This Trial: - Patient is, in the opinion of the investigator, mentally or legally incapacitated, preventing willing to sign a consent form from being obtained, or cannot read or understand the written material. - Subject has a daytime room air oxygen saturation \<90% while lying supine. - Patient is unable to perform spirometry or plethysmography maneuvers - Patient is pregnant - In the investigator's opinion, subject suffers from any physical, psychological or other condition(s) that might prevent performance of the MRI, such as severe claustrophobia. - Subject has an implanted mechanically, electrically or magnetically activated device or any metal in their body which cannot be removed, including but not limited to pacemakers, neurostimulators, biostimulators, implanted insulin pumps, aneurysm clips, bioprosthesis, artificial limb, metallic fragment or foreign body, shunt, surgical staples (including clips or metallic sutures and/or ear implants.) Always talk to your doctor about whether this trial is right for you.