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Alveoscopy, Endoscopic Confocal Microscopy and Lung Rejection, Parenchymal Lung Diseases in Vivo

This study has been completed.
Information provided by:
Mayo Clinic Identifier:
First received: December 15, 2009
Last updated: January 25, 2012
Last verified: January 2012

Lung transplantation is indicated when end-stage lung diseases no longer respond to available standard therapy, making life expectancy short and associated with disability. Acute and chronic rejection are common complications following transplantation, indicating screening bronchoscopies and transbronchial biopsies at three month intervals the first two years, in addition to clinically indicated procedures when rejection or infection is suspected. Transbronchial biopsies carry associated risks (bleeding, pneumothorax). Chronic rejection is characterized by progressive obliteration of distal airways (Bronchiolitis Obliterans-BO-). BO requires open lung biopsy for diagnosis. Alternatively, a clinical surrogate (Bronchiolitis Obliterans Syndrome), characterized by decline in Forced Expired Volume in 1 second not explained by acute rejection or infection is used for diagnosis. The new technique of confocal endo-microscopy enables sub-surface visualization of tissue in vivo during bronchoscopic procedures using a probe-based confocal microscope, integrated to a standard endoscope. Bronchiolar and alveolar structures can be visualized at a cellular and nuclear level, and these images can be saved and reviewed. This new technology could potentially identify acute and chronic rejection, thus offering and alternative to transbronchial biopsies. We expect to describe a new alternative to diagnose acute and chronic rejection using confocal microscopy images obtained endoscopically, obviating complications of transbronchial biopsies.

Endoscopic confocal endomicroscopy can detect and classify common bronchiolar and alveolar pathological conditions in real time. Specifically, we hypothesize that confocal endomicroscopy images of bronchiolar and alveolar structures during standard bronchoscopy could help to recognize and classify the presence/absence of acute rejection and/or bronchiolitis obliterans syndrome in lung transplant recipients. This technology could also identify the histological characteristics lung diseases such as interstitial, obstructive or vascular end stage lung diseases, and thus lead to more efficient, safer and more accurate diagnosis of these lung conditions during routine bronchoscopies.

Condition Intervention
Lung Transplant
Other: Confocal imaging

Study Type: Observational
Study Design: Observational Model: Case-Only
Time Perspective: Prospective
Official Title: The Role Of Endoscopic Alveoscopy by Confocal Endomicroscopy in Diagnosing Acute and Chronic Rejection in Lung Transplant Recipients, Diagnosis of End Stage Lung Disease, and Other Pulmonary Pathologies in Vivo

Resource links provided by NLM:

Further study details as provided by Mayo Clinic:

Primary Outcome Measures:
  • To determine in an unblinded study, the key image features of acute lung rejection and chronic lung rejection (BOS), and estimate which morphologic features best distinguish these conditions. [ Time Frame: One year ]

Secondary Outcome Measures:
  • To determine the initial sensitivity and specificity of confocal imaging for the classification of acute lung rejection among lung transplant recipients. [ Time Frame: One year ]
  • To develop a library of confocal images with the most optimal confocal imaging characteristics of other lung pathologies requiring lung transplantation. [ Time Frame: One year ]
  • To determine the inter-examiner differences and learning curve for accurate detection of acute rejection as well as the confocal images of other lung pathologies. [ Time Frame: One year ]
  • To determine in a unblinded pilot study, the key image features of chronic lung rejection as defined by the Bronchiolitis Obliterans Syndrome (BOS), and estimate which morphologic features best distinguish this conditions. [ Time Frame: One year ]

Enrollment: 71
Study Start Date: April 2008
Study Completion Date: March 2011
Primary Completion Date: March 2011 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Lung transplant
All lung transplant patients presenting for screening/surveillance and diagnostic bronchoscopies at Mayo Clinic Florida are eligible for participation.
Other: Confocal imaging
At the time of the standard of care bronchoscopy, confocal images will be obtained from each consented patient.
Other Names:
  • AlveoloFlex Confocal Miniprobes
  • Cellvizio-Lung system


Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Patients scheduled to undergo bronchoscopy either before or after lung transplantation.

Inclusion Criteria:

  1. Age above 18 years
  2. Any patient undergoing surveillance or clinically indicated bronchoscopies during or after lung transplantation
  3. Any patient undergoing bronchoscopy prior lung transplant

Exclusion Criteria:

  1. Unwilling to consent
  2. Unable to safely tolerate a bronchoscopic procedure
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01033201

United States, Florida
Mayo Clinic Florida
Jacksonville, Florida, United States, 32224
Sponsors and Collaborators
Mayo Clinic
  More Information


Responsible Party: Cesar A. Keller, M.D., Mayo Clinic Florida Identifier: NCT01033201     History of Changes
Other Study ID Numbers: 08-000800
Study First Received: December 15, 2009
Last Updated: January 25, 2012

Keywords provided by Mayo Clinic:
Lung rejection

Additional relevant MeSH terms:
Lung Diseases
Respiratory Tract Diseases processed this record on March 28, 2017