October 2016 Imaging Case of the Month

Michael B. Gotway, MD  

Department of Radiology

Mayo Clinic Arizona

Scottsdale, Arizona USA 

Imaging Case of the Month CME Information  

Members of the Arizona, New Mexico, Colorado and California Thoracic Societies and the Mayo Clinic are able to receive  0.25 AMA PRA Category 1 Credits™. Completion of an evaluation form is required to receive credit and a link is provided on the last panel of the activity.

0.25 AMA PRA Category 1 Credit(s)™

Estimated time to complete this activity: 0.25 hours

Lead Author(s): Michael B. Gotway, MD. All Faculty, CME Planning Committee Members, and the CME Office Reviewers have disclosed that they do not have any relevant financial relationships with commercial interests that would constitute a conflict of interest concerning this CME activity. 

Learning Objectives:
As a result of this activity I will be better able to:    

1. Correctly interpret and identify clinical practices supported by the highest quality available evidence.
2. Will be better able to establsh the optimal evaluation leading to a correct diagnosis for patients with pulmonary, critical care and sleep disorders.
3. Will improve the translation of the most current clinical information into the delivery of high quality care for patients.
4. Will integrate new treatment options in discussing available treatment alternatives for patients with pulmonary, critical care and sleep related disorders.

Learning Format: Case-based, interactive online course, including mandatory assessment questions (number of questions varies by case). Please also read the Technical Requirements.

CME Sponsor: University of Arizona College of Medicine at the Arizona Health Sciences Center.

Current Approval Period: January 1, 2015-December 31, 2016

Clinical History: A 35-year-old woman presented with a several month history of slowly worsening shortness of breath and dry cough. Laboratory data, include white blood cell count and serum chemistries were within normal limits. Oxygen saturation on room air was 99%.

Frontal and lateral chest radiographs (Figure 1) were performed.

Figure 1. Frontal (A) and lateral (B) radiographs.

Which of the following statements regarding the chest radiograph is most accurate? (Click on the correct answer to proceed to the second of seven panels)

1. Frontal and lateral chest radiography appears normal
2. Frontal and lateral chest radiography shows abnormally diminished lung volumes
3. Frontal and lateral chest radiography shows bilateral peribronchial and mediastinal lymph node enlargement
4. Frontal and lateral chest radiography shows cardiomegaly
5. Frontal and lateral chest radiography shows upper lobe bilateral linear and reticular abnormalities

Cite as: Gotway MB. October 2016 imaging case of the month. Southwest J Pulm Crit Care. 2016;13(4): . doi: http://dx.doi.org/10.13175/swjpcc100-16 PDF

Medical Image of the Week: Bronchopleural Fistula

Figure 1. The blue arrow indicates a fistulous communication between bronchus and the pleura.

Figure 2. Red arrow indicates radiotracer trapping in the pleural space and adjacent right anterior lower lung field.

A 58-year-old man with past medical history significant for chronic smoking and seizures was referred to the emergency room after a chest x-ray done by his primary care physician for evaluation of cough showed a hydropneumothorax. His symptoms included dry cough for past 2 months without fever, chills or other associated symptoms. He did not have any thoracic procedures performed and had no past history of recurrent infections. He was hemodynamically stable. Physical examination was only significant with decreased breath sounds on the right side of the chest.

Thoracic CT with contrast was performed which showed complete collapse of the right lower lobe, near complete collapse of right middle lobe as well as an air-fluid level. There was a suspicion of a direct communication between bronchi and pleural space at the posterior lateral margin of the collapsed right lower lobe (Figure 1). The presence of bronchopleural fistula (BPF) was confirmed with the help of lung scintigraphy, which showed trapping of radiotracer in the right lung at a location consistent with the chest CT findings of BPF (Figure 2). The patient was admitted and extensive infectious work up was negative. Biopsy of the right pleura was negative for malignancy. He underwent video-assisted thoracoscopic surgery (VATS) decortication of his right lung and was stable on subsequent follow up with complete resolution of his cough.

BPF has mortality rate between 18 to 67% (1). CT of the chest can occasionally demonstrate a direct fistulous communication, as seen in our case.  However, Westcott and Volpe (2) have shown sensitivity of CT chest to be 50%. Other useful noninvasive imaging techniques include lung scintigraphy. In this modality, the fistula is identified by seeing a trapping of radioisotope labeled gas as there is no mechanism for a clearance of gas after its diffusion into the pleural space.  Raja et al. (3) demonstrated that lung scintigraphy had 83% sensitivity and 100% specificity in diagnosing BPF.  

As seen in this case lung nuclear scintigraphy offers a cheaper, more sensitive, and less invasive approach to diagnosis of BPF.

Hem Desai MD, MPH and Anthony Witten DO

Department of Internal Medicine

University of Arizona

Tucson, AZ USA

References

1. Hollaus PH, Lax F, el-Nashef BB, Hauck HH, Lucciarini P, Pridun NS. Natural history of bronchopleural fistula after pneumonectomy: a review of 96 cases. Ann Thorac Surg. 1997 May;63(5):1391-6; discussion 1396-7. [CrossRef] [PubMed]
2. Westcott JL, Volpe JP. Peripheral bronchopleural fistula: CT evaluation in 20 patients with pneumonia, empyema, or postoperative air leak. Radiology. 1995 Jul;196(1):175-81. [CrossRef] [PubMed]
3. Raja S, Rice TW, Neumann DR, Saha GB, Khandekar S, MacIntyre WJ, Go RT. Scintigraphic detection of post-pneumonectomy bronchopleural fistulae. Eur J Nucl Med. 1999 Mar;26(3):215-9. [CrossRef] [PubMed] 

Cite as: Desai H, Witten A. Medical image of the week: bronchopleural fistula. Southwest J Pulm Crit Care. 2016;13(3)150-1. doi: http://dx.doi.org/10.13175/swjpcc069-16 PDF