To evaluate the potential of a new imaging device, termed Optical Frequency Domain Imaging (OFDI), in the early diagnosing of pulmonary malignancies in the central airways.

This study will evaluate the potential of a new imaging device, the Optical Frequency Domain Imaging (OFDI) for imaging pulmonary malignancy in the central airways.

The prevalence and high mortality rate associated with Lung Squamous Cell Carcinoma and the lack of any widely accepted screening and surveillance tools, highlights the need for new imaging paradigms that will ultimately lead to a reduction in patient mortality.

Bronchial carcinoma in-situ will progress to invasive cancer in over 40% of individuals, and although the progression occurs over a long period of time, the majority of carcinomas are detected in the later stages of disease development, offering patients only a very slim chance of cure. Although, significant effort in the development of screening paradigms for the detection of lung cancer in the central airway has been made, to date there is still no widely accepted and validated approach. Optical Frequency Domain Imaging (OFDI) is a recent derivative of optical coherence tomography (OCT). As in OCT, OFDI is an interferometric ranging technique that can roughly be considered to be an optical analogue of ultrasound imaging and can provide tomographic images of tissue at resolutions comparable with architectural histology. The long term goal of this study is to use OFDI to screen the airways with the hope of detecting Squamous Cell Carcinoma at an earlier more curable stage.

Standard of care bronchoscopy preparation and procedures to be followed, with moderate sedation, pulse oximetry and blood pressure monitoring as per department protocol. A combination of currently approved bronchoscopy techniques including stand white light bronchoscopy, autofluorescence bronchoscopy, and narrow band imaging will be used to assess the airways.

Bronchial regions of interest (ROI's)suspected to be premalignant or malignant, identified during the bronchoscopy procedure, will be imaged using the OFDI system and catheter before biopsy is done. It is anticipated to obtain a minimum of 3 OFDI-biopsy correlated pairs from each study participant. An additional OFDI image and biopsy will be obtained from region's of normal interest (ROI's). It is expected that the experimental procedure will add less than 10 minutes to the total length of the bronchoscopy procedure, but a stopping rule will be instituted to ensure that the experimental procedure does not exceed 20 minutes.

Inclusion Criteria:

• Patients undergoing bronchoscopy for known or suspected pulmonary malignancy in the central airways
• Patients must be over the age of 18
• Patient must be able to give informed consent
• Women with child bearing potential must have a negative pregnancy test within seven days prior to the procedure

Exclusion Criteria:

• PaO2 less than 80 on FiO2 greater 70%
• Systolic blood pressure less than 90
• Active bronchospasm
• INR greater than 2.0 (INR: International Normalized Ratio)
• Recent myocardial infarction within last two weeks
• Active cardiac chest pain
• Significant untreated sleep apnea
• FEV1 less than 30% of predicted (FEV1: forced expiratory volume in 1 second)
• Worsening hypercarbia with PaCO2 greater than 55
• In active respiratory failure (unless endotracheal intubation is performed first to stabilize the airway)