Imaging

Those who care for patients with pulmonary, critical care or sleep disorders rely heavily on chest radiology and pathology to determine diagnoses. The Southwest Journal of Pulmonary, Critical Care & Sleep publishes case-based articles with characteristic chest imaging and related pathology.

The editor of this section will oversee and coordinate the publication of a core of the most important chest imaging topics. In doing so, they encourage the submission of unsolicited manuscripts. It cannot be overemphasized that both radiologic and pathologic images must be of excellent quality. As a rule, 600 DPI is sufficient for radiographic and pathologic images. Taking pictures of plain chest radiographs and CT scans with a digital camera is strongly discouraged. The figures should be cited in the text and numbered consecutively. The stain used for pathology specimens and magnification should be mentioned in the figure legend. Those who care for patients with pulmonary, critical care or sleep disorders rely heavily on chest radiology and pathology to determine diagnoses. The Southwest Journal of Pulmonary, Critical Care & Sleep publishes case-based articles with characteristic chest imaging and related pathology. The editor of this section will oversee and coordinate the publication of a core of the most important chest imaging topics. In doing so, they encourage the submission of unsolicited manuscripts. It cannot be overemphasized that both radiologic and pathologic images must be of excellent quality. As a rule, 600 DPI is sufficient for radiographic and pathologic images. Taking pictures of plain chest radiographs and CT scans with a digital camera is strongly discouraged. The figures should be cited in the text and numbered consecutively. The stain used for pathology specimens and magnification should be mentioned in the figure legend.

Rick Robbins, M.D. Rick Robbins, M.D.

April 2017 Imaging Case of the Month

Michael B. Gotway, MD and John K. Sweeney, MD

Department of Radiology

Mayo Clinic Arizona

Scottsdale, Arizona USA

 

Clinical History: An 86-year-old man with a previous history of transcatheter aortic valve implantation 1 year earlier, coronary artery disease status-post coronary artery bypass grafting surgery 12 years earlier, atrial fibrillation on warfarin, and pacemaker placement 8 years earlier presented with altered mental status.

The patient’s white blood cell count was borderline elevated at 10.3 x 103/mcl (normal, 4.8 – 10.8 x 103/mcl)  and hyponatremia was noted (serum sodium = 129 mEq/L, normal =  136 – 145 mEq/L). The patient’s anticoagulation profile was within the therapeutic range (INR = 1.4), and the platelet count was normal. Oxygen saturation on room air was normal. The patient’s medication list included warfarin, digoxin, aspirin, metoprolol, montelukast, and atorvastatin.

Frontal chest radiography (Figure 1) was performed.

Figure 1. Frontal (A) and lateral (B) chest radiography.

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

  1. Frontal chest radiography shows a cavitary lung mass
  2. Frontal chest radiography shows focal consolidation suggesting aspiration pneumonia
  3. Frontal chest radiography shows increased pressure edema
  4. Frontal chest radiography shows malposition of the patient’s left subclavian pacemaker
  5. Frontal chest radiography shows rib fractures

Cite as: Gotway MB, Sweeney JK. April 2017 imaging case of the month. Southwest J Pulm Crit Care. 2017;14(4):141-52. doi: https://doi.org/10.13175/swjpcc042-17 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: VA Shunt Remnant Fibrosing into Right Atrium

Figure 1. Transthoracic echocardiography demonstrating tubular echo density in the right atrium (arrow).

 

Figure 2: Transesophageal echocardiography demonstrating the VA shunt remnant fibrosed (vs. calcified) in SVC (arrow) extending into right atrium (RA).

 

A 71-year-old man with a history of ventriculo-atrial (VA) shunt, removed in 2004 due to infection, was admitted to the hospital complaining of syncopal symptoms for one day’s duration. On presentation he denied any symptoms of syncope or focal weakness. The patient was placed on telemetry monitoring, and overnight observation demonstrated multiple sinus pauses with frequent episodes of premature atrial contractions. Stat transthoracic echocardiography (TTE) on the night of admission demonstrated a right tubular echodensity in the right atrium crossing the tricuspid valve (Figure 1). Follow up transesophageal echocardiography (TEE) redemonstrated evidence of a tubular structure in the SVC extending into the right atrium with evidence of fibrosis (?calcification)(Figure 2). These studies demonstrate the importance of echocardiographical work up in any patient with risk of retained foreign body even after reported removal (1).

Richard Young, MD; Joshua Sifuentes, MD; Joao Paulo Ferreira, MD

Department of Internal Medicine

Banner University Medical Center

University of Arizona

Tucson, Arizona USA

Reference

  1. Choi CH, Elahi MM, Konda S. Iatrogenic retained foreign body in the right atrium. Lessons to Learn. Int J Surg Case Rep. 2013;4(11):985-7. [CrossRef] [PubMed]

Cite as: Young R, Sifuentes J, Ferreira JP. Medical image of the week: VA shunt remnant fibrosing into right atrium. Southwest J Pulm Crit Care. 2017;14(3): 117-8. doi: https://doi.org/10.13175/swjpcc023-17 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: NG Tube Misplacement with a Pneumothorax

Figure 1.  CXR AP view showing misplaced NG tube in the right lung with small pneumothorax.

 

Figure 2. Follow up CXR AP view showing enlarged right pneumothorax after withdrawal of the NG tube.

  

Figure 3. CXR AP view post chest tube placement showing reinflation of the right lung.

 

Nasogastric tube (NG) placement is a common procedure performed in the inpatient hospital setting. They are often challenging to insert and therefore carry a risk of tracheobronchopleural, intravascular and enteral complications.

Our patient is a 90-year-old man who was admitted to the hospital with complaints of productive cough, fever, worsening of shortness of breath and confusion. He was diagnosed with viral upper respiratory tract infection, Legionella pneumonia and exacerbation of heart failure. Throughout his hospitalization patient had repeated episodes of delirium and had failed a swallowing evaluation. A NG was inserted for administration of enteral feeds and medications. There was no resistance to the passage of the tube when initially placed. However, post procedure CXR showed a misplaced nasogastric tube going into the right main bronchus and down into right lower lobe with a small apical pneumothorax (Figure 1). Follow up chest X-ray two hours later showed enlargement of the pneumothorax (Figure 2).  A 14 Fr pigtail catheter was promptly inserted in right pleural space. A repeat chest X-ray confirmed placement of the chest tube and showed re-inflation of the lung (Figure 3).

The reported incidence of misplacement of nasogastric tubes into the airways ranges from 0.3% to 15% and is more common after chest trauma or mechanical ventilation (1). This may be because of the need for adequate coordination of swallowing. Nasogastric tubes are generally considered safe, but there is a risk of significant pulmonary complications from blind insertion of small-caliber nasogastric tubes with a stiff stylet, particularly in elderly patients with altered mental status as well as with poor swallowing function (2).

Santhosh G. John MD, Vivian Keenan MD, Naveen Tyagi MD, and Priya Agarwala MD

Division of Pulmonary and Critical Care Medicine

Winthrop University Hospital

Mineola, New York USA

References

  1. Agha R, Siddiqui MR. Pneumothorax after nasogastric tube insertion. JRSM Short Rep. 2011 Apr 6;2(4):28. [CrossRef] [PubMed]
  2. Nazir T, Punekar S. Images in clinical medicine. Pneumothorax--an uncommon complication of a common procedure. N Engl J Med. 2010 Jul 29;363(5):462. [CrossRef] [PubMed] 

Cite as: John SG, Keenan V, Tyagi N, Agarwala P. Medical image of the week: NG tube misplacement with a pneumothorax. Southwest J Pulm Crit Care. 2017:14(1):14-5. doi: https://dx.doi/10.13175/swjpcc133-16 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Bronchial Clot Removal via Cryotherapy

Figure 1. Chest x-ray showing complete opacification of the left hemithorax.

 

Figure 2. Flexible bronchoscopy with cryotherapy was used to remove clot that formed casts of the bronchial tree. Black arrow: depicts segmental branch of the left upper lobe.

 

A 38-year-old man with a history of non-ischemic dilated cardiomyopathy presented with decompensated heart failure, acute renal failure, and possible sepsis. He underwent right cardiac catheterization but developed hemoptysis with concern for pulmonary artery rupture. Subsequently, the patient suffered a cardiac arrest but was resuscitated. Emergent bronchoscopy revealed copious amounts of blood and clot that could not be cleared at the time. The patient was then taken to the operating room and placed on A-A ECMO (left ventricle to aorta). The following morning chest x-ray (Figure 1) revealed a completely opacified left lung. Flexible bronchoscopy showed blood clot along the entire left bronchial tree. Initial attempts to remove the clot with suction and endobronchial graspers was unsuccessful. Ultimately, cryotherapy was used to remove the majority of the clot in fragments (Figure 2).

The use of cryotherapies and specifically, in this case, a cryoprobe, has been shown to safely and effectively remove thrombus from the bronchial tree. The basis behind this technique is the use of pressurized nitrous oxide or carbon dioxide to cool a metal probe tip. The probe then freezes any substance it comes in direct contact with, such as a blood clot. Thus, cryoadherence of the probe to the clot allows for effective removal via flexible endoscopy.  Sriratanaviriyakul et al. (1) reported success rates for cryoextraction of blood clots to be >90%.

Cathy V. Ho MD, Ryan Matika MD, and Mimi Amberger MD

1Division of Trauma, Critical Care, Burn and Emergency Surgery. Department of Surgery

2The Department of Anesthesia

University of Arizona

Tucson, AZ USA

Reference

  1. Sriratanaviriyakul N, Lam F, Morrissey BM, Stollenwerk N, Schivo M, Yoneda KY.Safety and clinical utility of flexible bronchoscopic cryoextraction in patients with non-neoplasm tracheobronchial obstruction: a retrospective chart review. J Bronchology Interv Pulmonol. 2015 Oct;22(4):288-93. [CrossRef] [PubMed] 

Cite as: Ho CV, Matika R, Amberger M. Medical image of the week: bronchial clot removal via cryotherapy. Southwest J Pulm Crit Care. 2016;13(5):253-4. doi: https://doi.org/10.13175/swjpcc109-16 PDF 

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Extrapleural Pneumolysis for Tuberculosis

Figure 1. PA (A)/Lateral (B) chest films showing a mass like opacity of the left upper lung field.

 

Figure 2. Representative image from the thoracic CT in soft tissue windows showing a well-circumscribed, oval-shaped, heterogeneous density within the left upper and mid anterior chest with some expansion and destruction of overlying ribs.

 

The advent of antibiotics revolutionized the management of tuberculosis, a disease that even in the 1950s was a top 10 cause of death in the United States. The first drug to be developed was streptomycin, approved after a clinical trial in 1946. The following decade saw the addition of ethambutol, rifampin, and isoniazid (1). Though we take for granted the use our multidrug regimens nowadays, physicians once had limited interventions for this frequent and devastating infection. Such interventions included surgical techniques to collapse the affected lobes, starving the mycobacterium of their preferred oxygen rich environment. One such technique was known as plombage, or extrapleural pneumolysis. Plombage is a term derived from the Latin for lead or plumbum and entails the insertion of a space occupying material into the pleural space with subsequent compression of the affected lung portion. This was seen as an alternative to the use of thoracoplasty, which required removal of multiple ribs allowing the chest wall to collapse, leading to deformity and a loss of lung function (2). Though rarely seen now, we present the imaging of an elderly female with endometrial cancer with lung metastasis who interestingly had undergone such a procedure when she developed cavitary tuberculosis as a teenager in 1952.

Tuffler first developed extrapleural pneumolysis in 1891; he placed fat into the pleural cavity reporting successful control of tuberculosis infection. The technique over the subsequent decades became popular especially as a response to the endemic tuberculosis seen post- the Second World War. Many attempts were made to designate an ideal inert material for use. Though unclear in our patient given the remote history of the procedure, published reports include placement of muscle, fat, air, mineral oil, gauze, paraffin, rubber sheeting, and even inflated Lucite balls. Fortunately, complications of the procedure, even decades later, are rarely seen now. Complications listed in the literature, however, do include infection, hemorrhage, fistula formation, migration of material, and even malignancy. Despite its popularity, there were mixed results in effectiveness and variable complication rates, in one series nearly 50% of patients developed an infection (3). In our patient, it was successful, with no history of recurrence with negative sputum and serologic testing. She did notably report having been treated with a long course of antibiotics as well.

Kareem Ahmad, MD

Department of Internal Medicine

Division of Pulmonary, Critical Care, Sleep, and Allergy Medicine

University of Arizona

Tucson, AZ, USA

References

  1. Zumla A, Nahid P, Cole ST. Advances in the development of new tuberculosis drugs and treatment regimens. Nat Rev Drug Discov. 2013 May;12(5):388-404. [CrossRef] [PubMed]
  2. Young FH. Extraperiosteal plombage in the treatment of pulmonary tuberculosis. Thorax. 1958; 13(2):130-5. [CrossRef] [PubMed]
  3. Murphy JD, Elrod PD, et al. Surgical treatment of residual cavities following thoracoplasties for tuberculosis. Dis Chest. 1948 Sep-Oct;14(5):694-706. [CrossRef] [PubMed]

Cite as: Ahmad K. Medical image of the week: extraplerural pneumolysis for tuberculosis. Southwest J Pulm Crit Care. 2016;13(5):244-5. doi: https://doi.org/10.13175/swjpcc106-16 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Tracheobronchial Foreign Body Aspiration

Figure 1. Panel A: The chest x-ray failed to show the aspirated foreign body. Panels B and C: Flexible bronchoscopy was performed and the insulin syringe cap was visualized in the right mainstem bronchus and retrieved with forceps.

 

Figure 2. Panel A: CT chest shows interval development of ground glass opacities and air fluid level in the right middle lobe (arrow). Panel B: The foreign body is visualized in the right lower lobe bronchus as an endobronchial-filling defect (arrow). Panel C: Flexible bronchoscopy was performed and cashew piece was retrieved with suction.

 

Case 1 (Figure 1) is a 58-year-old man who accidentally inhaled his insulin syringe cap while swinging on his recliner with the cap perched in his mouth. He developed a dry irritating cough. On exam he had mild stridor in the upper airways and bilateral wheezing. The insulin cap was visualized by bronchoscopy in the right mainstem bronchus and retrieved with forceps.

Case 2 (Figure 2) is a 65-year-old man with chronic dysphagia and poor dentition who choked on a cashew. It took repeated coughing attempts to produce the cashew, but it was unclear whether the entire content was cleared. He then developed non-massive hemoptysis that persisted for 2 weeks. Thoracic CT showed ground glass opacities and an air fluid level in the right middle lobe. The foreign body was visualized in the right lower lobe bronchus as an endobronchial-filling defect. Bronchoscopy revealed a cashew piece in the right lower lobe bronchus. Forceps trials failed due to fragility of the foreign body, which was ultimately retrieved with scope suction.

Rigid bronchoscopy is the gold standard for diagnosis and management of tracheobronchial foreign body aspiration, but flexible bronchoscopy is another accepted method that is also more comfortable for the patient (1). Virtual bronchoscopy is a noninvasive procedure that can assist with localizing the foreign body and may have a role to play in follow-up assessment of airway patency (2). Pneumonia and atelectasis are common complications. Less common complications include bronchiectasis, bronchostenosis, hemoptysis, tracheal perforation, pneumomediastinum, and even cardiopulmonary arrest (3). Tracheal foreign bodies pose more danger than bronchial foreign bodies; in such cases the foreign body should be pushed to distal airways, crumbled if it is organic, and then extracted (1).

Khushboo Goel, MD1, Huthayfa Ateeli, MBBS2, Joshua Dill, DO2, Dena L’Heureux MD3

1Department of Internal Medicine, University of Arizona, Tucson, AZ, USA

2Department of Internal Medicine, Division of Pulmonary, Critical Care, Sleep, and Allergy Medicine, University of Arizona, Tucson, AZ, USA

3Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Southern Arizona VA Health Care System, Tucson, AZ, USA

References

  1. Altunas B, Aydin Y, Eroglu A. Foreign bodies in trachea: a 25 year experience. Eurasian J Med. 2016;48(2):119-123. [CrossRef] [PubMed]
  2. Kshatriya RM, Khara NV, Paliwal RP, Patel SN. Role of virtual and flexible bronchoscopy in the management of a case of unnoticed foreign body aspiration presented as a nonresolving pneumonia in an adult female. Lung India. 2016; 33(4):420-423. [CrossRef] [PubMed]
  3. Altunas B, Aydin Y, Eroğlu A. Complications of tracheobronchial foreign bodies. Turk J Med Sci. 2016;46(3):785-800. [CrossRef] [PubMed]

Cite as: Goel K, Ateeli H, Dill J, L’Heureux D. Medical image of the week: tracheobronchial foreign body aspiration. Southwest J Pulm Crit Care. 2016;13(4):184-5. doi: http://dx.doi.org/10.13175/swjpcc092-16 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Abdominal Hematoma

 

Figure 1. Contrast-enhanced CT abdomen/pelvis showing A) coronal and B) sagittal views of a LLQ hematoma (blue braces) with active contrast extravasation (red arrow). Lines represent the level of respective axial images. C-F) Axial images demonstrating the hematoma within and expanding the rectus abdominis sheath (blue braces) as well as active contrast leak (red arrow).

 

Figure 2. A) Arteriogram demonstrating the large hematoma (solid arrow) with active extravasation of contrast from the inferior epigastric artery (arrowhead) arising from the external iliac artery (empty arrow). B) Coils in the inferior epigastric artery (arrow) block flow to the hematoma.

 

A 59 year-old man presented to clinic with acute-on-chronic non-productive cough along with sore throat and myalgias for 2 weeks and lower left quadrant (LLQ) abdominal pain for 2-3 days. He was a current smoker with history significant for COPD and mild “smoker’s cough” controlled with daily anticholinergic and as-needed beta-agonist, paroxysmal atrial fibrillation on dabigatran and diltiazem, hypertension controlled by diuretic, and a former alcoholic with hemochromatosis.

While getting an x-ray, he had a coughing fit resulting in abrupt worsening of his LLQ pain enough to inhibit ambulation. Due to his inability to walk, he came via ambulance to the emergency department, where he was mildly tachycardic with a 10cm firm, tender and ecchymotic LLQ mass.

Contrast-enhanced abdominal/pelvic CT demonstrated a large rectus abdominis hematoma. Figure 1 shows the hematoma within the rectus sheath measuring 16 cm with active contrast extravasation. The patient went directly to the interventional suite, where the left inferior epigastric artery was catheterized and subsequently embolized as shown in Figure 2.

The patient was noted to be in atrial fibrillation with rapid ventricular response (AFRVR), so was taken to the intensive care unit and placed on diltiazem drip, given digoxin and 1 unit of RBCs before his rhythm stabilized and he was transferred to the floor. His hemoglobin remained stable, and his cough and abdominal pain improved, so he was sent home off anticoagulation until follow-up with his cardiologist.

In the RE-LY trial, updated in 2010 (1), there was no difference in bleeding complications at this patient’s dosing of dabigatran compared to warfarin with INR of 2.0-3.0. However, this patient did not bleed into a critical area, require 2 units of RBCs, nor drop hemoglobin >2mg/dl, and would thus be considered having a minor bleeding event despite needing emergent embolization, losing enough blood to become tachycardic with resulting AFRVR, and getting 1 unit of RBC

Despite this particular bleeding complication, in a meta-analysis examining dabigatran vs warfarin, dabigatran uniformly was as good or better in preventing strokes with less devastating complications than warfarin (2). Additionally, although warfarin is touted as having vitamin K as its reversal agent, protein synthesis and secretion into the vasculature takes hours, similar in time to metabolically clear dabigatran (3).

In the end, after discussions about anticoagulants with the hospital team before discharge and his cardiologist thereafter, the patient elected to restart his dabigatran.

Michael Larson, M.D., Ph.D.

Banner-University Medical Center

University of Arizona

Medical Imaging Department

Tucson, AZ, USA

References

  1. Connolly SJ, Ezekowitz MD, Yusuf S, Reilly PA, Wallentin L; Randomized Evaluation of Long-Term Anticoagulation Therapy Investigators. Newly identified events in the RE-LY trial. N Engl J Med. 2010 Nov 4;363(19):1875-6. [CrossRef] [PubMed]
  2. Gómez-Outes A, Terleira-Fernández AI, Calvo-Rojas G, Suárez-Gea ML, Vargas-Castrillón E. Dabigatran, rivaroxaban, or apixaban versus warfarin in patients with nonvalvular atrial fibrillation: a systematic review and meta-analysis of subgroups. Thrombosis. 2013;2013:640723. [CrossRef] [PubMed]
  3. Ganetsky M, Babu KM, Salhanick SD, Brown RS, Boyer EW. Dabigatran: review of pharmacology and management of bleeding complications of this novel oral anticoagulant. J Med Toxicol. 2011 Dec;7(4):281-7. [CrossRef] [PubMed]

Cite as: Larson M. Medical image of the week: abdominal hematoma. Southwest J Pulm Crit Care. 2016:13(4): 176-8. doi: http://dx.doi.org/10.13175/swjpcc083-16 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Pneumothorax with Air Bronchograms

Figure 1. Panel (A) shows mild congestion with prominent bronchovascular markings. Panel (B) shows a large left pneumothorax with total collapse of the left lung marked by extensive airspace opacities and distinct air bronchograms. Panel (C) shows interval placement of a left-sided pigtail catheter with partial resolution of the left pneumothorax. There is persistent collapse of the medial aspect of the left upper lobe. Panel (D) shows complete resolution of the left pneumothorax and left lung atelectasis with continued bilateral airspace disease.

Development of pneumothoraces in critically ill patients is commonly encountered in the critical care unit (ICU). Incidence has been reported between 4-15% of patients. In most instances, pneumothorax in the ICU is considered a medical emergency especially when the patient is mechanically ventilated (1).  Here, we present a 61-year-old man with a past medical history of insulin dependent diabetes and paraplegia from prior spine injury who presented with acute respiratory distress after a pulseless electrical activity cardiac arrest. Cardiopulmonary resuscitation (CPR) was initiated by emergency medical services at home, and continued and the emergency department (ED) for a total of 30 minutes. The patient presented previously to the ED, one week prior, for a mild respiratory illness and tested positive for influenza B. He was sent home on oseltamivir. His family is unsure of compliance with medication but reported he was clinically stable up to the morning of presentation. The patient, as shown in the images, developed a left pneumothorax complicating an "adult respiratory distress syndrome (ARDS)- like" picture probably due to positive pressure ventilation with high positive end expiratory pressure, CPR, or both. The patient underwent immediate chest tube placement and with successful lung re-expansion. Unfortunately, his hemodynamic status/septic shock/multi-organ system failure continued to deteriorate within hours and he expired despite maximal support. Pneumothorax in patients with ARDS has higher morbidity and mortality compared to other critically ill patients due to the high-pressure needed during mechanical ventilation. This places patients at a high risk for the rapid progression to tension pneumothorax and even death. Therefore, in this high-risk population, a pneumothorax requires a high index of suspicion, prompt recognition, and immediate intervention (2).

Huthayfa Ateeli, MBBS and Steve Knoper, MD.

Department of Medicine, Division of Pulmonary, Critical Care, Sleep and Allergy Medicine. University of Arizona, Tucson, AZ USA

References

  1. Yarmus L, Feller-Kopman D. Pneumothorax in the critically ill patient. Chest. 2012 Apr;141(4):1098-105. [CrossRef] [PubMed] 
  2. Gattinoni L, Bombino M, Pelosi P, Lissoni A, Pesenti A, Fumagalli R, Tagliabue M. Lung structure and function in different stages of severe adult respiratory distress syndrome. JAMA. 1994 Jun 8;271(22):1772-9. [CrossRef] [PubMed] 

Cite as: Ateeli H, Knoper S. Medical image of the week: pneumothorax with air bronchograms. Southwest J Pulm Crit Care. 2016:13(3):129-30. doi: http://dx.doi.org/10.13175/swjpcc066-16 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

May 2016 Imaging Case of the Month

Michael B. Gotway, MD

 

Department of Radiology

Mayo Clinic Arizona

Scottsdale, AZ 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

Financial Support Received: None.

 

Clinical History:  A 58-year-old man with hypertension presents for a routine health examination. As part of his routine evaluation, frontal and lateral chest radiography (Figure 1) was performed.  

Figure 1. Frontal (panel A) and lateral (panel B) chest radiography.

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

Cite as: Gotway MB. May 2016 imaging case of the month. Southwes J Pulm Crit Care. 2016 May;12(5):180-91. doi: http://dx.doi.org/10.13175/swjpcc040-16 PDF 

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Rick Robbins, M.D. Rick Robbins, M.D.

April 2016 Imaging Case of the Month

Michael B. Gotway, MD

 

Department of Radiology

Mayo Clinic Arizona

Scottsdale, AZ 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

Financial Support Received: None.

 

Clinical History: A 19 year-old man with no previous medical history was vacationing when he was found down, intoxicated, surrounded by vomit. He went into cardiac arrest, and, after several minutes, cardiopulmonary resuscitation was initiated. He was intubated in the field, and epinephrine was administered.

Once at the hospital, frontal chest radiography (Figure 1) was performed.

Figure 1. Frontal chest radiograph.

Which of the following statements regarding the chest radiograph is most accurate?

Cite as: Gotway MB. April 2016 imaging case of the month. Southwest J Pulm Crit Care. 2016 Apr;12(4):137-46. doi: http://dx.doi.org/10.13175/swjpcc035-16 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Virtual Anatomical Dissociation During Electromagnetic Navigation Bronchoscopy

Figure 1. During the first navigation virtual bronchoscope image and 3D map (top left and bottom left) show the tip of the locatable guide in the posterior segment of the right upper lobe matching live video bronchoscope image.

 

Figure 2. Second navigation: the virtual bronchoscope image and 3D map (top left and bottom left) show the tip of the bronchoscope in the right main bronchus whereas the video bronchoscope shows the tip in the posterior segment of the right upper lobe.

A 59 year-old woman with a 40 pack-year smoking history was referred to our practice with a 2.5 cm spiculated right upper lobe lung nodule for a diagnostic bronchoscopy.

We performed electromagnetic navigation bronchoscopy under general anesthesia in the operating room. After successfully navigating to the lesion and obtaining 3 needle biopsy samples and two cytology brush samples we lost target alignment. After attempting to rotate and reposition the catheter several times it was decided to re-navigate from the trachea. Two images comparing virtual navigation to real anatomy during the first and second navigation attempts are provided bellow (Figures 1 and 2).

Why are the virtual images different? (Click on the correct answer for a discussion)

Cite as: Vazquez-Guillamet R, Horn E, Sarver R, Melendres L. Medical image of the week: virtual anatomical dissociation during electromagnetic navigation bronchoscopy. Southwest J Pulm Crit Care. 2015;11(5):238-9. doi: http://dx.doi.org/10.13175/swjpcc111-15 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medial Image of the Week: Palmar Erythema Multiforme

Figure 1. Palmar rash in a patient with acute pulmonary coccidioidomycosis resembling erythema multiforme.

An 18 year-old male presented for evaluation of abnormal chest imaging. Prior to moving to Tucson, Arizona three weeks before presentation, he was diagnosed with ankylosing spondylitis and was started on adalimumab (Humira). Approximately one week prior to presentation he developed a fever and cough. Over 3-4 days the cough worsened and he developed a palmar rash (Figure 1). He was seen in the emergency department and was started on levofloxacin. Prior to presentation in the pulmonary clinic his rash had resolved but the cough had persisted. Chest imaging showed airspace opacities within the left upper lobe with associated small left pleural effusion. Bronchoalveolar lavage revealed 57% eosinophils. Fungal cultures, bacterial cultures, and cytology were non-diagnostic. Coccidioides IgG antibody was negative but Coccidioides IgM antibody converted to positive, suggesting acute infection. The patient was started on oral fluconazole and clinically improved. Erythema nodosum and erythema multiforme are noted in as many as 25 % of patients with acute pulmonary coccidioidomycosis. The rashes usually occur within a few days of infection and are considered a good prognostic sign (1).

Ryan Nahapetian, MD, MPH and Joshua Malo, MD

Pulmonary, Allergy, Critical Care, & Sleep Medicine

University of Arizona, Tucson, AZ

Reference

  1. Smith JA, Riddell J 4th, Kauffman CA. Cutaneous manifestations of endemic mycoses. Curr Infect Dis Rep. 2013;15(5):440-9. [CrossRef] [PubMed]

Cite as: Nahapetian R, Malo J. Medical image of the week: palmar erythema multiforme. Southwest J Pulm Crit Care. 2015;11(5):217. doi: http://dx.doi.org/10.13175/swjpcc102-15 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Acute Amiodarone Pulmonary Toxicity

Figure 1. Chest X-ray showing diffuse interstitial markings, right upper lobe consolidation, small pleural effusions, thoracotomy wires and external leads.

 

Figure 2. Axial image of the thoracic CT scan showing increased interstitial markings, ground glass opacities and bilateral pleural effusions.

 

A 71 year old man with a medical history significant for chronic obstructive pulmonary disease, coronary artery disease with post-operative status coronary artery bypass grafting, heart failure with reduced ejection fraction (25%) and atrial fibrillation/flutter underwent an elective ablation of the tachyarrhythmia at another facility and was prescribed amiodarone post procedure. He started complaining of cough and dyspnea one day post procedure and was empirically treated with 2 weeks of broad spectrum antibiotics. He subsequently was transferred to our facility due to worsening symptoms. He also complained of nausea, anorexia with resultant weight loss since starting amiodarone, which was stopped 5 days prior to transfer. Infectious work up was negative.

On arrival to our facility, he was diagnosed with small sub-segmental pulmonary emboli, pulmonary edema and possible acute amiodarone toxicity. His was profoundly hypoxic requiring high flow nasal cannula or 100% non-rebreather mask at all times. His symptoms persisted despite antibiotics, diuresis, anticoagulation and heart rate control. Steroid therapy was then initiated for acute amiodarone toxicity. Although he reported some improvement in symptoms 2-3 days after initiation of steroids, his oxygen requirement did not improve. Unfortunately he suffered a cardiac arrest on day 10 of admission and did not survive.

Amiodarone is a class B anti-arrhythmic used to treat multiple supraventricular and ventricular tachyarrhythmias. Its adverse effects are usually dose and duration dependent. Amiodarone pulmonary toxicity (APT) has been shown to correlate with total cumulative dose; however acute reactions to amiodarone toxicity have previously been reported. Men are at increased risk for APT, and this risk increases with age and those with pre-existing lung conditions. Diagnosis of APT is predominantly a diagnosis of exclusion; however laboratory tests may show leukocytosis with neutrophil predominance (as in our patient) and imaging may provide a clue for diagnosis. Chest x-ray reveals patchy or diffuse infiltrates, which may have predominance in the upper lobes, particularly the right upper lobe (as in our patient). A thoracic CT scan may show bilateral alveolar or interstitial infiltrates with higher attenuation, secondary to the iodine component of the drug. The current mainstay of treatment is discontinuation of the drug permanently along with steroid therapy typically, 40-60 mg of prednisone a day for an extended period of time.  

Konstantin Mazursky DO1, Bhupinder Natt MD2, Laura Meinke MD1,2

1Department of Internal Medicine.

2Division of Pulmonary, Critical Care, Allergy and Sleep

Banner-University Medical Center

Tucson AZ

Reference

  1. Wolkove N, Baltzan M. Amiodarone pulmonary toxicity. Can Respir J. 2009;16(2):43-8. [PubMed] 

Cite as: Mazursky K, Natt B, Meinke L. Medical image of the week: acute amiodarone pulmonary toxicity. Southwest J Pulm Crit Care. 2015;11(4):189-90. doi: http://dx.doi.org/10.13175/swjpcc099-15 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Septated Pleural Effusion

Figure 1. Thoracic ultrasound showing pleural effusion with multiple septations.

An 83 year old man with a history of metastatic malignant melanoma and atrial fibrillation on warfarin was admitted for shortness of breath. He underwent a diagnostic and therapeutic thoracentesis for a large right sided pleural effusion, suspected to be malignancy related. Three days later, he had transferred to the ICU for respiratory distress. An ultrasound of the thorax revealed a large loculated effusion with multiple septations (Figure 1). A large bore chest tube was placed and revealed a hemothorax, which may have been related to the previous thoracentesis.

In an observational study of ultrasound characteristics of pleural effusions, complex septations were more commonly seen in non-malignant effusions than malignant effusions (25.4% vs. 7.5%). In non-malignant effusions, the septated pattern was associated with infections, specifically tuberculosis and pneumonia (1).

While metastases in melanoma commonly involve the thoracic cavity, malignant pleural effusions are rare and are seen in about 2% of cases. In very rare instances, effusions from metastatic melanoma can be black in appearance (2). There has also been a case report of a massive hemothorax related to melanoma implants on the pleura (3).

Candy Wong, MD1; Soyoung Park, MD2; Courtney Walker, DO2; and Laura Meinke, MD1

1Division of Pulmonary, Allergy, Critical Care, and Sleep, Department of Medicine.

2Department of Medicine

University of Arizona

Tucson, AZ

References

  1. Bugalho A, Ferreira D, Dias SS, Schuhmann M, Branco JC, Marques Gomes MJ, Eberhardt R. The diagnostic value of transthoracic ultrasonographic features in predicting malignancy in undiagnosed pleural effusions: a prospective observational study. Respiration. 2014;87:270-8. [CrossRef] [PubMed]
  2. Liao WC, Chen CH, Tu CY. Black pleural effusion in melanoma. CMAJ. 2010;182(8):E314. [CrossRef] [PubMed]
  3. Gibbons JA, Devig PM. Massive hemothorax due to metastatic malignant melanoma. Chest. 1978;73(1):123. [CrossRef] [PubMed]

Cite as: Wong C, Park S, Walker C, Meinke L. Medical image of the week: septated pleural effusion. Southwest J Pulm Crit Care. 2015;11:110-1. doi: http://dx.doi.org/10.13175/swjpcc085-15 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Ascaris Lumbricoides

Figure 1. 23 cm adult Ascaris lumbricodes recovered from patient's feces.

A 25 year-old man was admitted to the ICU with acute renal failure and acute respiratory failure from fluid overload after attempting to cross the border. The patient was successfully extubated after five days of mechanical ventilation and renal replacement therapy. Following extubation, the patient had a bowel movement and passed a 23cm adult Ascaris lumbricoides. He was treated with a single dose of albendazole 400 mg.

Ascariasis is a very common helminthic infection, particularly in pediatric populations, and affects mostly the gastrointestinal tract. When infective eggs are swallowed by the host, larvae hatch in the GI tract. The larvae invade the GI mucosa and then are brought into the lungs via portal circulation. The larvae can then move up the tracheobronchial tree and then are swallowed into the GI tract where the mature worms form (1).

While our patient had a simple gastrointestinal infection, several pulmonary complications of ascariasis have been reported (2). Adult worms can cause largyngospasm as well as mechanical obstruction of the airway which can result in cardiac arrest (3,4). This migration of worms from the stomach to the trachea may be related to the use of anesthetics and the subsequent relaxation of the lower esophageal sphincter. Ascaris larvae have been implicated in Loeffler’s syndrome, also described as simple pulmonary eosinophilia, characterized by transient pulmonary infiltrates and eosinophilia with a usually benign course.

Candy Wong1; Aaron Fernandes2, Jennifer Huang2, and Sachin Chaudhary1

1Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine.

2 Department of Medicine

University of Arizona

Tucson, AZ

References

  1. Centers for Disease Control and Prevention. Parasites – Ascariasis. Biology. Available at: http://www.cdc.gov/parasites/ascariasis/biology.html (accessed 1/13/2015).
  2. Li QY, Zhao DH, Qu HY, Zhou CN. Life-threatening complications of ascariasis in trauma patients: a review of the literature. World J Emerg Med. 2014;5(3):165-70. [CrossRef] [PubMed]
  3. Maletin M, Veselinović I, Stojiljkovic GB, Vapa D, Budakov B. Death due to an unrecognized ascariasis infestation: two medicolegal autopsy cases. Am J Forensic Med Pathol. 2009;30(3):292-4. [CrossRef] [PubMed]
  4. Husain SJ, Zubairi AB, Sultan N, Beg MA, Mehraj V. Recurrent episodes of upper airway blockage associated with Ascaris lumbricoides causing cardiopulmonary arrest in a young patient. BMJ Case Rep. 2009;2009. pii: bcr01.2009.1415. [CrossRef] [PubMed]

Reference as: Wong C, Fernandes A, Huang J, Chaudhary S. Medical image of the week: ascaris lumbridoies. Souhtwest J Pulm Crit Care. 2015;10(2):81-2. doi: http://dx.doi.org/10.13175/swjpcc008-15 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Dobhoff Placement in a Patient with Hiatal Hernia

Figure 1. Arrows designate tip of Dobhoff feeding tube (DHT). Panel A: Chest radiograph. DHT appears to follow the left main bronchus into the left lower lobe. Panel B: Abdominal view of DHT placement. Panel C: Chest CT showing degree of hiatal hernia and DHT in the intra-thoracic hernia. Panel D: Follow-up fluoroscopy imaging showing appropriately placed DHT in the duodenum.

A 79 year-old woman with a past medical history of obstructive sleep apnea, chronic obstructive pulmonary disease on home oxygen, obesity hypoventilation syndrome, hypertension, and anxiety presented with a 2 day history of altered mental status and symptoms consistent with a COPD exacerbation, including dyspnea and increased oxygen requirements. She was found to be hypercarbic and did not tolerate a trial of BiPAP due to her altered mentation. She was subsequently intubated. Due to an expected prolonged intubation period, plans for enteral access were made. A Dobhoff naso-duodenal feeding tube (DHT) was inserted. On chest radiograph and a concurrent abdominal radiograph, the DHT appeared to have been inserted into the left mainstem bronchus terminating in the left lower lobe (Figure 1A and 1B). The nursing staff removed and replaced the DHT resulting in a similar radiograph. A third placement was attempted with similar radiographic results. Therefore, a computed tomography (CT) scan of the chest was performed to evaluate tube placement. The CT of the chest showed a large hiatal hernia contained within thoracic cavity (Figure 1C). Upon chart review, previous radiographs mentioned hiatal hernia but it appeared that the degree of herniation had progressed. Fluoroscopy was used to confirm placement of the DHT beyond the herniated gastric contents into the duodenum (Figure 1D) and tube feeds were initiated.

Post-pyloric feeding tubes are often used in place of gastric feeding tubes under the assumption that the risk of aspiration in the intubated patient is reduced. Enteral nutrition is typically started within 36 hours of intubation as this has been shown to decrease mortality in intubated patients (1). There are contraindications to the use of nasogastric or nasoenteric feeding tubes, which include facial trauma, esophageal web, or recent esophagectomy. Hiatal hernias are not a contraindication to nasoenteric feeding tube placement, however, patients with unusual anatomy may benefit from placement under fluoroscopic or endoscopic visualization in order to ensure appropriate positioning (2).

Kawanjit K Sekhon, MD and Ryan Nahapetian, MD, MPH

Department of Internal Medicine

Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine

University of Arizona, Tucson, AZ

References

1. Marik PE, Zaloga GP. Gastric versus post-pyloric feeding: a systematic review. Crit Care. 2003;7(3):R46-51. [CrossRef] [PubMed]

2. Hodin RA, Bordeianou L. Nasogastric and nasoenteric tubes. Uptodate.com. Oct 17, 2013. Dec 20, 2013. Available at: http://www.uptodate.com/contents/nasogastric-and-nasoenteric-tubes?source=machineLearning&search=hiatal+hernia+feeding+tube&selectedTitle=1%7E150&sectionRank=3&anchor=H522922014#H522922014 (requires subscription).

Reference as: Sekhon KK, Nahapetian R. Medical image of the week: Dobhoff placement in a patient with hiatal hernia. Southwest J Pulm Crit Care. 2015;10(1):49-50. doi: http://dx.doi.org/10.13175/swjpcc005-15 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

January 2015 Imaging Case of the Month

Michael B. Gotway, MD

 

Department of Radiology

Mayo Clinic Arizona

Scottsdale, AZ

  

Clinical History: A 68-year-old woman with a history of myelodysplastic syndrome associated with transfusion-dependent anemia and thrombocytopenia presented with recent onset left chest pain and fever. The patient had a remote history of total right knee arthroplasty, hypertension, asthma, and schizoaffective disorder. Several months earlier the patient was hospitalized with methicillin-sensitive Staphylococcus aureus infection involving the right knee arthroplasty, associated with bacteremia and a septic right elbow. This infection was treated with incision and drainage of the elbow, antibiotic bead placement about the right knee arthroplasty with an antibiotic-impregnated spacer, and antibiotics (6 weeks intravenous cefazolin followed by chronic doxycycline suppression therapy, the former later switched to nafcillin and rifampin). The patient had been discharged from the hospital with only compression hose for deep venous thrombosis prophylaxis, owing to her episodes of epistaxis in the setting of transfusion-dependent anemia.

Upon presentation, the patient was hypotensive, tachycardic, and hypotensive. Laboratory data showed a white cell count of 3.9 cells x 109 / L, a platelet count of 7000 x 109 / L, and a hemoglobin level of 7 g/dL.

Frontal chest radiography (Figure 1A) was performed (a baseline chest radiograph- Figure 1B- is presented for comparison).

 

Figure 1. Panel A: Frontal chest radiography Panel B: Frontal chest radiograph obtained 3 months to presentation.

Which of the following statements regarding the chest radiograph is most accurate? (Click on the correct answer to proceed to the 2nd of 7 panels)

Reference as: Gotway MB. January 2015 imaging case of the month. Southwest J Pulm Crit Care. 2015;10(1):21-31. doi: http://dx.doi.org/10.13175/swjpcc003-15 PDF

 

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Tracheal Perforation

Figure 1. Axial thoracic CT scan showing air in the mediastinum (red arrow).

 

Figure 2. Coronal thoracic CT scan showing air in the mediastinum (orange arrow).

 

Figure 3. Axial thoracic CT scan showing air in the mediastinum (yellow arrow).

 

Figure 4. Axial thoracic CT scan showing pneumopericardium (blue arrow).

 

A 45 year old Caucasian man with a history of HIV/AIDS was admitted for septic shock secondary to right lower lobe community acquired pneumonia. The patient’s respiratory status continued to decline requiring emergency intubation in a non-ICU setting. Four laryngoscope intubation attempts were made including an inadvertent esophageal intubation. Subsequent CT imaging revealed a tracheal defect (Figure 1, red arrow) with communication to the mediastinum and air around the trachea consistent with pneumomediastinum (Figure 2, orange arrow and figure 3, yellow arrow). Pneumopericardium (figure 4, blue arrow) was also evident post-intubation. The patient’s hemodynamic status remained stable. Two days following respiratory intubation subsequent chest imaging revealed resolution of the pneumomediastinum and pneumopericardium and patient continued to do well without hemodynamic compromise or presence of subcutaneous emphysema. Post-intubation tracheal perforation is a rare complication of traumatic intubation and may be managed with surgical intervention or conservative treatment (1).

Nour Parsa MD, Konstantin Mazursky DO, Sepehr Daheshpour MD, Naser Mahmoud MD

Department of Medicine

University of Arizona

Tucson, AZ

Reference

  1. Fan CM, Ko PC, Tsai KC, Chiang WC, Chang YC, Chen WJ, Yuan A. Tracheal rupture complicating emergent endotracheal intubation. Am J Emerg Med. 2004;22(4):289-93. [CrossRef] [PubMed]

Reference as: Parsa N, Mazursky K, Daheshpour S, Mahmoud N. Medical image of the week: tracheal perforation. Southwest J Pulm Crit Care. 2014;9(6):335-6. doi: http://dx.doi.org/10.13175/swjpcc159-14 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Pulmonary Herniation

Figure 1. Thoracic CT scan.

 

  Figure 2. Saggital view of thoracic CT scan.

 

A 49-year-old obese gentleman with a known history of chronic obstructive pulmonary disease, diabetes mellitus and GERD presented with complaints of a popping sensation in his left chest with coughing and deep breathing, associated with pain at the same site. Physical examination showed small bulge at the level of the herniation that was most obvious with coughing. CT scan of chest done 2 months ago showed 2. 5 cm pulmonary hernia identified at the left 7-8 costal interspace (Figures 1 and 2). This was thought to have resulted from an open lung biopsy of his left lung done 4 years before presentation to evaluate for acute respiratory failure or chest tube insertion at same site 3 years prior to presentation for treatment of a pneumothorax. Surgical repair was done with round Bard Kugel hernia patch. His symptoms resolved after the procedure.

 

Ramasubramanian Baalachandran MD, Naser Mahmou  MD, and Laura Meinke MD

Department of Medicine

University of Arizona – School of Medicine

Tucson, Arizona.

Reference

  1. Fackeldey V, Junge K, Hinck D, Franke A, Willis S, Becker HP, Schumpelick V. Repair of intercostal pulmonary herniation. Hernia. 2003;7(4):215-7. [CrossRef] [PubMed]

Reference as: Baalachandran R, Mahmou N, Meinke L. Medical image of the week: pulmonary herniation. Southwest J Pulm Crit Care. 2014;9(4):197-8. doi: http://dx.doi.org/10.13175/swjpcc122-14 PDF

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Rick Robbins, M.D. Rick Robbins, M.D.

Medical Image of the Week: Pneumatocele

Figure 1. Portable AP film showing a large cystic lesion in the left lower lobe in addition to small bilateral pleural effusions and adjacent consolidation.

Figure 2. Axial enhanced CT scan section showing a large cystic space with an air-fluid level with adjacent consolidated atelectasis. No perceptible wall is seen.

A 50-year-old man presented with polymicrobial pneumonia which included Proteus mirabilis, Enterobacter cloacea and MRSA pathogens. A large cystic lesion with an air-fluid level was found on chest imaging in a region of pneumonia (Figure 1). There was associated mass effect onto the adjacent lung. No perceptible wall was noted which would be more associated with a cyst rather than a cavity or abscess. Directed aspiration of this lesion resulted in decompression without further complication. Minimal sterile fluid was recovered. Therefore the proposed diagnosis was a pneumatocele within the setting of infection. Pneumatoceles may be challenging at times to distinguish from a cavity particularly when surrounded by airspace disease however merit consideration in the differential diagnosis particularly in the absence of findings of a thick irregular wall.

The exact mechanism causing development of a pneumatocele is not known, but believed to develop due to a check valve type bronchiole or bronchiolar obstruction (1). Pneumatoceles most commonly undergo spontaneous remission within weeks to months without any known long term implications. Complications occur rarely and include pneumothorax, tension pneumatocele, and secondary infection of a pneumatocele. Usual treatment is directed towards the underlying pneumonia with appropriate antibiotics. In rare cases percutaneous drainage may be necessary and is ideally performed with a small bore catheter to minimize trauma. The role of positive pressure ventilation in development of a pneumatocele is unclear.

Bhupinder Natt, MD and Veronica Arteaga, MD

Divisions of Pulmonary and Thoracic Imaging

University of Arizona College of Medicine

Tucson, AZ

Reference

  1. Lysy J, Werczberger A, Globus M, Chowers I. Pneumatocele formation in a patient with Proteus mirabilis pneumonia. Postgrad Med J. 1985;61(713):255-7. [CrossRef] [PubMed]

Reference as: Natt B, Arteaga V. Medical image of the week: pneumatocele. Southwest J Pulm Crit Care. 2014;9(2):126-7. doi: http://dx.doi.org/10.13175/swjpcc102-14 PDF

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