Medical Image of the Month: Superior Vena Cava Syndrome

Figure 1. Large mediastinal lymph nodes (red arrow) causing compression of the superior vena cava (blue arrow). Numerous enlarged lymph nodes can also be seen in the axillary, cervical, and upper abdominal regions (green arrows).

History: A 74-year- old man with a history of diastolic heart failure, chronic kidney disease (CKD), and chronic lymphocytic leukemia (CLL) presented with a complaint of dyspnea. He has had several hospitalizations in the last year for heart failure exacerbation and his home bumetanide was recently increased from twice to three times daily due to persistently increasing weight. His CLL was diagnosed two years prior and treatment was stopped three months ago due to side effects. In the emergency department he reported three weeks of worsening dyspnea especially when lying flat, as well as increased swelling in his legs, abdomen, arms, and face. His weight was up to 277lbs from 238lbs the month before. His diuretics were transitioned to IV, but over the next few days he remained clinically volume overloaded. A noncontrast chest CT was obtained to help evaluate his ongoing respiratory distress (Figure 1). It demonstrated innumerable lymph nodes involving the cervical, axillary, mediastinal, and upper abdominal regions, which had significantly increased in size and number from prior exam several months before. The CT also showed several particularly bulky lymph nodes which appeared to be compressing the superior vena cava.

Discussion: The superior vena cava (SVC) is responsible for about one-third of the venous return to the heart. Because of its thin walls relative to arterial vasculature, it is susceptible to compression from adjacent structures which may subsequently impair venous return to the heart, a process known as SVC syndrome. Intrathoracic malignancy is responsible for 60-85% of cases of SVC syndrome, and common symptoms include facial or neck swelling, swelling of the arms, and dyspnea (1). In this case, the patient’s apparent resistance to diuresis was felt to be partially secondary to SVC syndrome. In stable patients, contrast-enhanced CT is the preferred imaging modality if SVC syndrome is suspected, which can define the extent of SVC blockage. Duplex ultrasound may be used first to exclude thrombus. In this patient with acute kidney injury on CKD it was decided to forgo the contrast study to avoid further kidney damage. Management of SVC syndrome depends on severity, with emergent treatment focused on maintaining the airway and endovenous recanalization. Definitive treatment is directed at the underlying cause (2).

After about a week of aggressive IV diuresis, the patient’s breathing and volume status improved and he was transitioned back to oral diuretics. He was discharged home with plans for hospice.

Matthew R. Borchart MD, Daniel Yu MD, and Indrajit Nandi MD

University of Arizona College of Medicine, Phoenix

Phoenix, AZ USA

References

1. Rice TW, Rodriguez RM, Light RW. The superior vena cava syndrome: clinical characteristics and evolving etiology. Medicine (Baltimore). 2006 Jan;85(1):37-42. [CrossRef] [PubMed]
2. Wilson LD, Detterbeck FC, Yahalom J. Clinical practice. Superior vena cava syndrome with malignant causes. N Engl J Med. 2007 May 3;356(18):1862-9. [CrossRef] [PubMed]

Cite as: Borchart MR, Yu D, Nandi I. Medical Image of the Month: Superior Vena Cava Syndrome. Southwest J Pulm Crit Care. 2020;21(6):136-7. doi: https://doi.org/10.13175/swjpcc060-20 PDF

Medical Image of the Month: Buffalo Chest Identified at the Time of Lung Nodule Biopsy

Figure 1. Buffalo chest, peripheral cavitary lesions, and pneumothorax contralateral to the biopsy site. A) Outpatient CT scan showing a right pneumothorax (blue arrow) and right-sided cavitary lesion (blue arrowhead). B) Subsequent pre-procedural planning CT scan done right lateral decubitus, showing again the cavitary lesion (blue arrowhead) but now with left pneumothorax (red arrow), suggesting buffalo chest. C) Intra-procedural CT showing needle at the periphery of the cavitary lesion (blue arrowhead) and similar-sized left pneumothorax (red arrow). D) 5-minute post-procedural CT demonstrating expected alveolar hemorrhage in the site of the biopsied cavitary lesion (blue arrowhead), but worsening left pneumothorax (red arrow). E & F) Multiple peripheral left lung cavitary lesions (red arrowheads) felt to be possible culprits for the worsened pneumothorax following coughing from the right-sided biopsy.

A gentleman in his late 50s with a past medical history of squamous cell carcinoma at the base of the tongue had numerous slowly-growing pneumocyst-like lesions despite clinical remission status post surgery and chemoradiation. Biopsy of one of these lesions was recommended by a multidisciplinary tumor board.

An outpatient pre-procedural supine chest CT revealed a right pneumothorax above the lesion targeted for biopsy. A subsequent pre-procedural right lateral decubitus chest CT three weeks later demonstrated a left-sided pneumothorax, raising concern for buffalo chest. (A less likely possibility would be spontaneous resolution of the right pneumothorax and development of a new left pneumothorax in the less than 4-week interval.) Intraprocedural imaging continued to demonstrate the left-sided pneumothorax. A biopsy touch preparation of the first sample obtained did not demonstrate malignancy. Therefore, an attempt was made at obtaining another sample. However, the patient developed a brief but forceful coughing fit, resulting in the termination of the procedure after only 2 passes of a 20g needle. Post-procedural scans demonstrated expected right-sided alveolar hemorrhage near the biopsy tract but slight worsening of the contralateral pneumothorax. The patient was again scanned five minutes later for concerns of a worsening pneumothorax. CT imaging demonstrated stable right-sided alveolar hemorrhage near the biopsy tract, but also severe left sided pneumothorax with multiple peripheral cavitary lesions. A left anterior chest tube was placed and the patient was discharged a few days later. Biopsy results showed granulomatous tissue only and cultures were negative.

Buffalo chest refers to the abnormal presence of a pleuro-pleural communication in humans. This phenomenon derives its name from the fact that buffalo and similar species possess one contiguous pleural space, while humans ordinarily have two independent pleural spaces corresponding to each lung (1). This pleuro-pleural communication can develop iatrogenically, congenitally, or as a result of trauma. Cases of buffalo chest developing after median sternotomy, laparoscopic surgery and heart-lung transplantation have been described in the literature (2). It is unknown if the worsening of our patient’s left-sided pneumothorax occurred in the setting of underlying buffalo chest, with biopsy producing a right sided pneumothorax that subsequently communicated with the left pleural space. Alternatively, our patient’s episode of forceful coughing could have increased the intrathoracic pressure and caused barotrauma to one of the many peripheral cavitary lesions previously described, leading to a worsening of the left-sided pneumothorax. Cases of bilateral pneumothoraces where interpleural connections exist have been successfully treated with a unilateral chest tube (2, 3). A second chest tube may be necessary in cases where the contralateral lung fails to re-expand. Our patient was able to be discharged after placement of a unilateral chest tube (contralateral to the biopsy side), reaffirming the general recommendation to treat pneumothoraces this patient population with a unilateral pleural catheter.

Phillip Belone MS4, Jason Lee MD, and Michael Craig Larson MD PhD

University of Arizona/Banner University Medical Center-Tucson

Department of Medical Imaging

Tucson, AZ USA

References

1. Jacobi A, Eber C, Weinberger A, Friedman SN. Bilateral Pneumothoraces after Unilateral Lung Biopsy. A Case of "Buffalo Chest"? Am J Respir Crit Care Med. 2016 Apr 15;193(8):e36. [CrossRef] [PubMed]
2. Sawalha L, Gibbons WJ. Iatrogenic "buffalo chest" bilateral pneumothoraces following unilateral transbronchial lung biopsies in a bilateral lung transplant recipient. Respir Med Case Rep. 2015 May 16;15:57-8. [CrossRef] [PubMed]
3. Groarke J, Breen D, O'Connell F, O'Donnell R. Bilateral pneumothorax resulting from a diagnostic thoracentesis. Eur Respir J. 2007 Nov;30(5):1018-9; diagnosis 1020. [CrossRef] [PubMed]

Cite as: Belone P, Lee J, Larson MC. Medical Image of the Month: Buffalo Chest Identified at the Time of Lung Nodule Biopsy. Southwest J Pulm Crit Care. 2020;21(5):121-3. doi: https://doi.org/10.13175/swjpcc056-20 PDF