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.

Medical Image of the Week: Post-Traumatic Diaphragmatic Rupture

Figure 1. A: Admission portable chest radiograph, demonstrates elevation of the right hemidiaphragm of uncertain chronicity (large arrow, also shown in B and C). B: Study after 20 min, shows a moderate hemothorax (*). Mildly displaced fractures are evident, involving at least the3rd and 5th right ribs (small arrows). C: Follow up exam. A right chest tube (thin arrow in c) has been inserted, and the hemothorax is drained. Immediately after, a CT chest abdomen and pelvis is performed.

 

Figure 2. A-C: A large anterolateral diaphragmatic defect is diagnosed, as shown in the coronal images, from anterior to posterior (A-C), with displacement of the liver (L) and loops of bowel (B) into the chest. Note the discontinuity of the diaphragm (arrows in A, B and D). A small liver laceration is noted in the gallbladder bed (arrows in C). D:  Image, near the midline, showing atelectasis (A) in the posterior right lung base. Additional injuries (not shown), included, right ribs 2-11 fractures, gallbladder fossa liver, right adrenal hemorrhage, mesenteric root contusion and multiple pelvic fractures.

 

A 67-year-old woman was admitted after being struck by a vehicle, at high speed. She has a diaphragmatic rupture (Figures 1 and 2).

Diaphragmatic injuries occur in approximately 0.8%–8% of blunt trauma patients, largely from motor vehicle accidents (1). The mechanism of injury includes distortion of the chest wall with resulting shearing forces, or direct frontal impact with acute increased intraabdominal pressure (2).

Rupture of the left diaphragm is more common, presumably due to a protective mechanism by the liver, but also in part due to underdiagnoses (3). Most ruptures are large, posterolateral, between the lumbar and intercostal attachments (4).  Associated liver injuries are seen mostly with right diaphragmatic injuries (93 % vs. 24% with left injuries). Multiorgan abdominal injury and pelvic fractures are common (2).

In cases of associated hemothorax, pulmonary laceration/contusion, atelectasis, and phrenic nerve palsy, a diaphragmatic injury, may be masked on chest radiographs. Also, the positive pressure of ventilatory support may delay herniation of abdominal contents through the ruptured diaphragm (5).

Up to 12% to 66% cases of diaphragmatic rupture cases, are missed on chest radiograph. Suggestive findings include elevation of the hemidiaphragm, distortion or obliteration of the outline of the hemidiaphragm, and contralateral shift of the mediastinum (6,7).

On CT visualization of a diaphragmatic defect has most sensitivity and specificity for diaphragmatic injury (73% and 90%) respectively) (8). Intrathoracic herniation of abdominal contents has a sensitivity of 55% and a specificity of 100% (8). The “collar sign”, a waist-like constriction of the herniating hollow viscus at the site of the diaphragmatic tear, is usually seen sagittal and coronal multiplanar reformatted images (2,8). The “dependent viscera sign” (1), consists of bowel or solid organs fallen to a dependent position against the posterior ribs, due to lack of supported by the intact diaphragm. This may be an early sign of diaphragmatic tear on axial images, before visceral herniation is clearly seen on multiplanar reformatted images.

Diana Palacio MD, Veronica Arteaga MD, Berndt Schmidt MD

Department of Medical Imaging

The University of Arizona-Banner Medical Center

Tucson, AZ USA

References

  1. Bergin D, Ennis R, Keogh C, et al. The "dependent viscera" sign in CT diagnosis of blunt traumatic diaphragmatic rupture. AJR Am J Roentgenol. 2001;177:1137-40. [CrossRef] [PubMed]
  2. Shanmuganathan K, Killeen K, Mirvis SE, et al. Imaging of diaphragmatic injuries. J Thorac Imaging. 2000;15:104-11. [CrossRef] [PubMed]
  3. Killeen KL, Mirvis SE, Shanmuganathan K. Helical CT of diaphragmatic rupture caused by blunt trauma. AJR Am J Roentgenol.1999;173:1611-6. [CrossRef] [PubMed]
  4. Boulanger BR, Milzman DP, Rosati C, et al. A comparison of right and left blunt traumatic diaphragmatic rupture. J Trauma. 1993;35:255-60. [CrossRef] [PubMed]
  5. Kuhlman JE, Pozniak MA, Collins J, Knisely BL. Radiographic and CT findings of blunt chest trauma: aortic injuries and looking beyond them. RadioGraphics. 1998;18:1085-1106. [CrossRef] [PubMed]
  6. Iochum S, Ludig T, Walter F, et al. Imaging of Diaphragmatic Injury: A Diagnostic Challenge RadioGraphics 2002; 22:suppl. 1,S103-16. [CrossRef] [PubMed]
  7. Gelman R, Mirvis SE, Gens D. Diaphragmatic rupture due to blunt trauma: sensitivity of plain chest radiographs. AJR Am J Roentgenol. 1991;156:51-7. [CrossRef] [PubMed]
  8. Murray JG, Caoili E, Gruden JF, et al. Acute rupture of the diaphragm due to blunt trauma: diagnostic sensitivity and specificity of CT. AJR Am J Roentgenol. 1996;166:10. [CrossRef] [PubMed]

Cite as: Palacio D, Arteaga V, Schmidt B. Medical image of the week: post-trumatic diaphragmatic rupture. Southwest J Pulm Crit Care. 2018;16(3):143-5. doi: https://doi.org/10.13175/swjpcc030-18 PDF 

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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: 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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