Comparison of Transbronchial, Cryoprobe and VATS Biopsy For the Diagnosis of Interstitial Lung Disease (ILD)

The objective of this study is to compare the sample size, architectural preservation and diagnostic yield of bronchoscopic cryo-probe transbronchial lung biopsy (C-TBBx) to bronchoscopic standard transbronchial lung biopsy (S-TBBx) and Video-Assisted Thoracoscopic Surgery (VATS) lung biopsy for the diagnosis of interstitial lung disease (ILD).

This is a prospective cohort study in which 20 subjects that have suspected ILD who are undergoing non-emergent surgical biopsy will be enrolled.

Patients who have been referred to the thoracic surgery service for VATS biopsy to diagnose suspected ILD and meet basic inclusion/exclusion criteria will be approached by the study investigators and informed of the study. An informed consent will be obtained during the clinic visit with the thoracic surgeon.

At the beginning of the surgical procedure, under general anesthesia in the operating room, patients will undergo flexible bronchoscopy through the endotracheal tube and obtain 10 standard transbronchial biopsies (S-TBBx) and 5 Cryoprobe biopsies (C-TBBx) with fluoroscopic guidance. S-TBBx will be performed using standard biopsy forceps (Boston Scientific, Natick, MA) - 2.0mm diameter. C-TBBx will be performed using the cryoprobe (ERBE, Tubingen, Germany) -1.9 mm diameter, 78cm in length. This cryoprobe is routinely used in the bronchoscopy suite for other applications such as foreign body removal and local treatment of carcinoma; therefore it is a technique already employed by the interventional pulmonologists who are familiar with its use. Once the biopsies are obtained by the interventional pulmonologist, the thoracic surgeon will perform video-assisted thoracoscopic biopsy (VATS) biopsy. Following their procedure, subjects will be monitored in the post-anesthesia care unit as per standard of care. As part of their ongoing follow-up care, all subjects will be monitored for any adverse events that may have resulted from either the surgical or bronchoscopic procedure, specifically bleeding or pneumothorax.

All biopsy samples will be analyzed by a specialist in pulmonary pathology.

The number and size of all biopsies, architectural preservation of the airways/alveoli, and pathological diagnosis will be reported by the pathologist. Diagnostic yield will be calculated for each biopsy technique and compared.

Eligibility Criteria:
Inclusion Criteria:

* Subject provides informed consent
* Subject is \>18 years of age
* Subject is scheduled to undergo VATS biopsy for suspected ILD as part of their standard medical care
* A negative pregnancy test in women of child-bearing potential
* Subject is mentally capable of understanding study procedures

Exclusion Criteria:

* Study subject has any disease or condition that interferes with safe completion of the study including:

  * Platelet count \< 50,000 or Coagulopathy defined as an International Normalized Ratio (INR) \> 1.5 on the day of procedure, as well as discontinuation of ticagrelor or clopidogrel within 5 days of procedure.
  * Severely impaired lung function as determined with spirometry evidenced by a forced expiratory volume in 1 second (FEV1) \< 0.8, or radiographically as diffuse bullous disease
  * Hemodynamic instability with systolic blood pressure \<90 mmHg or heart rate \> 120 beats/min, unless deemed to be stable with these values by the surgical or interventional pulmonary attending physicians
  * Hypoxemia with pulse oximetry values \<88% or partial pressure of oxygen in arterial blood (PaO2) \< 60 on baseline oxygen requirements
* Concurrent participation in another study involving investigational drugs or investigational medical devices
* Inability to read and understand the necessary study documents