Medical Image of the Month: Double Aortic Arch

Figure 1. A chest radiograph performed after endotracheal intubation of the patient demonstrated prominence of the upper mediastinum in the region of the right paratracheal strip (red arrow).

Figure 2. A non-contrasted CT of the chest demonstrates a complete vascular ring secondary to the patient’s double aortic arch (outlined in red) surrounding the trachea (T) and esophagus (E).

Case Presentation: A 78-year-old gentleman presented to the hospital via EMS with altered mental status. An urgent CT of the head performed in the emergency room demonstrated a large, right intraparenchymal hemorrhage with intraventricular extension into the right lateral ventricle. His Glascow Coma Scale score was 6, and he was intubated for airway protection.  A chest radiograph performed to verify placement of the endotracheal tube demonstrated prominence of the upper mediastinum in the region of the right paratracheal strip (Figure 1). A CT of the chest (Figure 2) demonstrated a double aortic arch corresponding to the upper mediastinal abnormality noted on the chest radiograph. In speaking with the patient’s family after acquiring the CT of the chest, they stated that the patient had long-term issues with dysphagia – specifically choking with solid foods. Unfortunately, the patient passed away from complications of his large intraparenchymal hemorrhage.

A double aortic arch results from persistence of both the right and left embryonic arches with each arch giving rise to the ipsilateral, separate carotid and subclavian arteries (1). A double aortic arch is the most common cause of a symptomatic vascular ring with the trachea and esophagus being compressed by the two arches (1). Symptoms usually arise in childhood with good outcomes with surgical repair of this abnormality in pediatric populations. A few case series exist describing repair of this anomaly in adult populations (2).

Kelly Wickstrom DO, Steven P. Sears DO, and Laura Meinke MD

Division of Pulmonary, Critical Care, Allergy and Sleep Medicine

University of Arizona College of Medicine

Tucson, AZ USA

References

1. Hanneman K, Newman B, Chan F. Congenital variants and anomalies of the aortic arch. Radiographics. 2017 Jan-Feb;37(1):32-51. [CrossRef] [PubMed]
2. Noguchi K, Hori D, Nomura Y, Tanaka H. Double aortic arch in an adult. Interact Cardiovasc Thorac Surg. 2012 Jun;14(6):900-2. [CrossRef] [PubMed]

Cite as: Wickstrom K, Sears SP, Meinke L. Medical image of the month: Double aortic arch. Southwest J Pulm Crit Care. 2019;18(5):120-1. doi: https://doi.org/10.13175/swjpcc019-19 PDF 

Medical Image of the Week: Post Pneumonectomy Syndrome

Figure 1.Computed tomography of the chest. Panel A: lung windows reveal hyperexpansion of right lung with extreme shift of mediastinum to the left hemithorax. Panel B: mediastinal windows reveals rotation of the heart toward midline.

A 73 year-old woman with a history of left pneumonectomy in 2012 for Stage IB adenocarcinoma of the lung presented to the outpatient pulmonary clinic with dyspnea on exertion and fatigue. Computed tomography of the chest reveals hyperexpansion of the right lung with complete shift of the heart and mediastinal structures into the left hemithorax, (Figure  1). There is tethering of the right mainstem bronchus and right-sided vessels with a stretched configuration of the trachea, esophagus and right-sided vasculature.  The heart is rotated toward the midline. The central airways are patent, however, the tethering and rotation of the mediastinal structures are concerning for post-pneumonectomy syndrome (PPS).

PPS is a rare and late complication after pneumonectomy and results from extreme shift and rotation of the mediastinum. Symptoms can include progressive dyspnea, cough, inspiratory stridor and recurrent pneumonia (1). Dyspnea can be caused by bronchial compression or by compression of the pulmonary vein (2). Dysphagia and acid reflux can result from esophageal compression (3). PPS is more common after right pneumonectomy, however cases following left pneumonectomy are well described. Treatment options include surgical correction using saline‐filled tissue expanders to restore normal mediastinal position (4).

Billie Bixby MD and James Knepler MD

Division of Pulmonary, Allergy, Critical Care and Sleep

University of Arizona

University Medical Center Tucson

Tucson, AZ USA

References

1. Valii, AM, Maziak DE, Shamii FM, Matzinger RF. Postpneumonectomy syndrome: recognition and management. Chest. 1998; 114:1766. [CrossRef] [PubMed]
2. Partington SL, Graham A, Weeks SG. Pulmonary vein stenosis following left pneumonectomy: a variant contributor to postpneumonectomy syndrome. Chest. 2010;137(1):205-6. [CrossRef] [PubMed]
3. Soll C, Hahnloser D, Frauenfelder T, Russi EW, Weder W, Kestenholz PB. The postpneumonectomy syndrome: Clinical presentation and treatment. Eur J Cardiothorac Surg. 2009; 35: 319-24. [CrossRef] [PubMed]
4. Jung JJ, Cho JH, Kim HK, et al. Management of post‐pneumonectomy syndrome using tissue expanders. Thoracic Cancer. 2016;7(1):88-93. [CrossRef] [PubMed]

Cite as: Bixby B, Knepler J. Medical image of the week: post pneumonectomy syndrome. Southwest J Pulm Crit Care. 2018;16(6):332-3. doi: https://doi.org/10.13175/swjpcc071-18 PDF 

Medical Image of the Week: Mediastinal Lipomatosis

Figure 1. Chest X-ray showing right sided mediastinal mass.

Figure 2. Coronal (A) and axial (B) CT Images showing a right paratracheal homogenously fat-enhancing mass.

A 61-year-old man presented to the pulmonary clinic for evaluation of a chronic cough of 6 months’ duration.  Other medical problems included class three obesity, obstructive sleep apnea on CPAP therapy, and hypertension.  Chest X-Ray (Figure 1) revealed a right mediastinal mass which then prompted a chest CT to be performed. The chest CT (Figure 2) demonstrated a homogenously enhancing, well circumscribed and fat-attenuating 8 x 5 cm mass in the right paratracheal region without invasion or compression into surrounding structures.

Mediastinal lipomatosis was diagnosed.  This is a benign soft tissue tumor made of mature adipocytes that can be seen with obesity, chronic corticosteroid use, and Cushing’s syndrome.  They are thought to represent up to 2.3% of all primary mediastinal tumors (1).  They are occasionally associated with compression of surrounding structures which can cause superior vena cava syndrome, dry cough, dysphagia, and occasionally arrhythmias (2).  Management is typically conservative with weight loss encouraged unless mass effect is present that significantly affects quality of life, in which case surgical options may be explored. 

Although this patient’s cough could be due to this lipoma, he also had symptoms of cough possibly exacerbated by severe gastroesophageal reflux disease which was not yet managed.  A trial of a proton pump inhibitor was pursued with follow-up arranged to determine if further intervention is necessary.

Bryan Borg MD and James Knepler MD

Department of Medicine

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

University of Arizona

Tucson, AZ USA

References

1. Gaerte SC, Meyer CA, Winer-Muram HT. Fat-containing lesions of the chest. Radiographics. 2002;22:61-78. [CrossRef] [PubMed]
2. Cutilli T, Schietroma M, Marcelli VA, Ascani G, Corbacelli A. Giant cervico-mediastinal lipoma. A clinical case. Minerva Stomatol. 1999 Jan-Feb;48(1-2):23-8. [PubMed]

Cite as: Borg B, Knepler J. Medical image of the week: mediastinal lipomasosis. Southwest J Pulm Crit Care. 2018;16:228-9. doi: https://doi.org/10.13175/swjpcc046-18 PDF 

May 2017 Imaging Case of the Month

Prasad M. Panse, MD and Michael B. Gotway, MD

Department of Radiology

Mayo Clinic Arizona

Scottsdale, Arizona USA

Clinical History: Clinical History: A 32-year-old man presented for routine physical examination. His past medical history is unremarkable and the physical examination and basic laboratory data were within normal limits.

A frontal chest radiograph (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 nine pages)

1. The frontal chest radiograph shows an abnormal mediastinal contour
2. The frontal chest radiograph shows basal predominant fibrotic abnormalities
3. The frontal chest radiograph shows large lung volumes with a cystic appearance
4. The frontal chest radiograph shows multifocal small pulmonary nodules
5. The frontal chest radiograph shows no abnormal findings

Cite as: Panse PM, Gotway MB. May 2017 imaging case of the month. Southwest J Pulm Crit Care. 2017;14(5):201-12. doi: https://doi.org/10.13175/swjpcc055-17 PDF 

June 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 65-year-old non-smoking man with a past medical history significant only for dyslipidemia and hypertension presented to the emergency room with a 2-week complaint of intermittent, diffuse, high back pain accompanied by sweating and nausea and non-bloody emesis. The back pain does not radiate. The patient also notes that recently he has suffered from pronounced fatigue and some shortness of breath; until recently he had been an endurance athlete.

Physical Examination: Physical examination was normal; in particular, the back pain was not reproducible on palpation. The patient was afebrile.

Laboratory: Laboratory data were remarkable for a mildly elevated white blood cell count of 11 x 10⁹ cells/L. Serum chemistries were within normal limits and cardiac troponins were negative. Oxygen saturation on room air was 94%.

Radiography: Frontal and lateral 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 panels)

1. The frontal chest radiograph shows a large left pleural effusion
2. The frontal chest radiograph shows an abnormally widened mediastinum
3. The frontal chest radiograph shows multifocal consolidation
4. The frontal chest radiograph shows no significant findings
5. The frontal chest radiograph shows numerous small lung nodules

Cite as: Gotway MB. June 2016 imaging case of the month. Southwest J Pulm Crit Care. 2016 Jun;12(6):216-28. doi: http://dx.doi.org/10.13175/swjpcc047-16 PDF 

Medical Image of the Week: Mediastinal Metastases Causing Right Ventricular Outflow Obstruction

Figure 1. Computed tomography (CT) of chest showed large right mediastinal mass (arrow) causing mass effect on the heart.

Figure 2.  Echocardiography showing large extra-cardiac mass (white arrow) compressing on right ventricle and its outflow tract (black arrow).

A 36-year-old man with a history of testicular choriocarcinoma with metastases to the lung presented with a 2-days history of hemoptysis. Initial diagnosis of the malignancy was made about 5 months earlier and he was treated with platinum based chemotherapy with a partial response.

He reported two days of significant hemoptysis, associated with shortness of breath and pleuritic chest pain and rapidly developed acute hypoxic respiratory failure requiring emergent intubation and mechanical ventilation. Computed tomography (CT) of chest showed large right mediastinal mass with diffuse reticular and nodular opacities predominantly in the left lung (Figure 1).

A pulmonary angiogram was performed that showed multiple active bleeding sites in the bronchial arterial system. These were treated with embolization. He developed shock and during investigations the echocardiogram showed a significant compression of the superior vena cava, right atrium and right ventricle by the malignant mass (Figure 2). Despite aggressive therapy and resuscitative therapies he continued to deteriorate and did not survive the hospital stay.

Mediastinal tumors are a rare cause of extrinsic right ventricular outflow tract (RVOT) obstruction. Echocardiography is an important tool in the assessment of hemodynamic effects caused due to such pathology including degree of compression and pressure gradients.

Kai Rou Tey MD¹, Bhupinder Natt MD²

¹Department of Internal Medicine, University of Arizona College of Medicine- South Campus, Tucson, AZ USA

²Division of Pulmonary, Critical Care, Allergy and Sleep, University of Arizona Medical Center, Tucson, AZ USA

Cite as: Tey KR, Natt B. Medical image of the week: mediastinal metastases causing right ventricular outflow obstruction. Southwest J Pulm Crit Care. 2016:12(1):22-3. doi: http://dx.doi.org/10.13175/swjpcc145-15 PDF