Currently chest X-ray (CXR) is the modality used to assess for pneumothorax after transthoracic lung biopsy at the Ottawa Hospital. Recently bedside Ultrasound (US) has become a useful rapid imaging modality to assess chest for pneumothorax in emergency rooms with reported sensitivity, specificity and diagnostic accuracy were 88%, 97% and 97%, respectively (ref. 2).

Our team will be comparing the diagnostic accuracy of US to CXR in diagnoses of pneumothorax post transthoracic lung biopsy.

The purpose of the study is to compare the diagnostic accuracy of US to CXR post-biopsy to confirm the presence of a pneumothorax.

Hypothesis:

US have sensitivity and specificity equal or better than CXR to exclude pneumothorax after transthoracic lung biopsy.

Clinical relevance:

Pneumothorax is a well-known complication of image-guided transthoracic biopsy of lung lesions. The incidence of pneumothorax in patients undergoing TTNB has been reported to be from 9% to 54% (ref. 3). Most of the time, the pneumothorax is small and requires no further intervention other than observation and a repeat CXR to ensure stability or resolution of the pneumothorax. In small group of patients with detected pneumothorax after biopsy, the pneumothorax is either large or becomes larger (more than 2 cm width at the level of the hilum) during observation. In these cases, a small pleural drainage catheter will be inserted to prevent the lung from collapsing. The catheter will be removed in 2 days. Detection of pneumothorax post biopsy is important to prevent possible lung collapse after discharge and currently is done by obtaining a CXR, 30 minutes after the biopsy.

Obtaining a CXR, requires moving the patient on stretcher to the X-ray room, bringing the patient to upright position, patient holds breath. An X-ray technologist obtains the CXR which will be reviewed by a Radiologist when it becomes available on work station. Then the Radiologist revisits the patient and orders the discharge.

Detection of pneumothorax by US is feasible and compare to current practice with CXR, is faster and do not need moving and repositioning the patient, therefore, more convenient. It can be easily performed at the time of clinical assessment prior to discharge.

Study design/ Methodology:

• All patients coming for lung biopsy will be invited to participate in this study. Information about the one additional US at the time of their biopsy and routine CXR will be explained to the patient by either thoracic radiology fellow or staff radiologist.
• For those who agree to participate, informed Consent will be obtained by the same people mentioned above.
• There will be no change in clinical assessment or decision to discharge the patient after biopsy.
• US will be performed by a trained staff radiologist or thoracic fellow.

Inclusion Criteria:

• Patients who are booked and coming for image-guided transthoracic biopsy of a lung lesion to the Ottawa Hospital, General Campus, will be consented and those who agree to added US will be included

Exclusion Criteria:

• Other patients.