Radiographic Evaluation of a Pulmonary Embolism Jim Hadstate September 27, 2007
Presentation <ul><li>Dyspnea </li></ul><ul><li>Pleuritic chest pain </li></ul><ul><li>Low-grade fever </li></ul><ul><li>Ta...
Evaluation <ul><li>ABG – Respiratory alkalosis, hypoxia </li></ul><ul><li>ECG – Sinus tachycardia & S1Q3T3 </li></ul><ul><...
CXR <ul><li>Initial CXR usually normal. </li></ul><ul><li>May progress to show atelectasis, plueral effusion and elevated ...
CXR <ul><li>Hampton’s Hump – consists of a pleura based shallow wedge-shaped consolidation in the lung periphery with the ...
CXR <ul><li>Westermark sign  – Dilatation of pulmonary vessels proximal to embolism along with collapse of distal vessels,...
V/Q Scan <ul><li>Ventilation-perfusion scanning is a radiological procedure which is often used to confirm or exclude the ...
Abnormal V/Q Scan
Abnormal V/Q Scan Perfusion Ventilation
V/Q Scan Results Likelihood of pulmonary embolism according to scan category and clinical probability in PIOPED study  2 6...
Spiral CT <ul><li>Spiral CT first introduced in 1990s </li></ul><ul><li>In older CT scanners, the X-ray source would move ...
Spiral CT <ul><li>Major advantage of Spiral CT is speed: </li></ul><ul><ul><li>Often the patient can hold their breath for...
CT Angiogram <ul><li>Quickly becoming the test of choice for initial evaluation of a suspected PE. </li></ul><ul><li>CT un...
CT Angiogram <ul><li>Chest computed tomography scanning demonstrating extensive embolization of the pulmonary arteries. </...
Pulmonary angiogram <ul><li>Gold Standard. </li></ul><ul><li>Positive angiogram provides 100% certainty that an obstructio...
Pulmonary angiogram <ul><li>Left-sided pulmonary angiogram showing extensive filling defects within the left pulmonary art...
Summary <ul><li>Plain chest radiograph – Usually normal and non-specific signs. </li></ul><ul><li>Radionuclide ventilation...
 
References <ul><li>Up to date Online. Diagnosis of Acute Pulmonary Embolism. Last revised March 7, 2007. </li></ul><ul><li...
Upcoming SlideShare
Loading in …5
×

Radiographic evaluation of a Pulmonary Embolism

982
-1

Published on

0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
982
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
50
Comments
0
Likes
2
Embeds 0
No embeds

No notes for slide

Radiographic evaluation of a Pulmonary Embolism

  1. 1. Radiographic Evaluation of a Pulmonary Embolism Jim Hadstate September 27, 2007
  2. 2. Presentation <ul><li>Dyspnea </li></ul><ul><li>Pleuritic chest pain </li></ul><ul><li>Low-grade fever </li></ul><ul><li>Tachycardia </li></ul>
  3. 3. Evaluation <ul><li>ABG – Respiratory alkalosis, hypoxia </li></ul><ul><li>ECG – Sinus tachycardia & S1Q3T3 </li></ul><ul><li>D-Dimer – A negative result rules out PE </li></ul><ul><li>CXR </li></ul><ul><li>V/Q Scan </li></ul><ul><li>Spiral CT with contrast </li></ul><ul><li>Angiogram </li></ul>
  4. 4. CXR <ul><li>Initial CXR usually normal. </li></ul><ul><li>May progress to show atelectasis, plueral effusion and elevated hemidiaphram. </li></ul><ul><li>Hampton’s hump and Westermark sign are classic findings but are not usually present. </li></ul>
  5. 5. CXR <ul><li>Hampton’s Hump – consists of a pleura based shallow wedge-shaped consolidation in the lung periphery with the base against the pleural surface. </li></ul>
  6. 6. CXR <ul><li>Westermark sign – Dilatation of pulmonary vessels proximal to embolism along with collapse of distal vessels, often with a sharp cut off. </li></ul>
  7. 7. V/Q Scan <ul><li>Ventilation-perfusion scanning is a radiological procedure which is often used to confirm or exclude the diagnosis of pulmonary embolism. It may also be used to monitor treatment. </li></ul><ul><li>Ventilation (V) – Achieved by the inhalation of Technetium DTPA. DTPA is an elongated version of EDTA and is a heavy metal chelator. Ventilation is assessed under a gamma camera. </li></ul><ul><li>Perfusion (Q) – Achieved by injecting the patient with Technetium 99m, which is coupled with macro aggregated albumin (MAA). An embolus shows up as a cold area when the patient is placed under a gamma camera. </li></ul>
  8. 8. Abnormal V/Q Scan
  9. 9. Abnormal V/Q Scan Perfusion Ventilation
  10. 10. V/Q Scan Results Likelihood of pulmonary embolism according to scan category and clinical probability in PIOPED study 2 6 0 Normal or near normal Clinical probability of emboli 4 15 40 Low 15 28 66 Intermediate 56 86 95 High Low Intermediate High Scan Category
  11. 11. Spiral CT <ul><li>Spiral CT first introduced in 1990s </li></ul><ul><li>In older CT scanners, the X-ray source would move in a circular fashion to acquire a single slice. Once the slice had been completed, the scanner table would move to position the patient for the next slice. </li></ul><ul><li>In helical CT the X-ray source and detectors are attached to a freely rotating gantry. During a scan, the table moves the patient smoothly through the scanner. The name derives from the helical or spiral path traced out by the X-ray beam. </li></ul>
  12. 12. Spiral CT <ul><li>Major advantage of Spiral CT is speed: </li></ul><ul><ul><li>Often the patient can hold their breath for the entire study, reducing motion artifacts. </li></ul></ul><ul><ul><li>Allows for more optimal use of intravenous contrast enhancement. </li></ul></ul><ul><ul><li>Spiral CT is quicker than the equivalent conventional CT permitting the use of higher resolution acquisitions in the same study time. </li></ul></ul><ul><li>Contraindicated in cases of renal disease. </li></ul><ul><li>Sensitive for PE in the proximal pulmonary arteries, but less so in the distal segments. </li></ul>
  13. 13. CT Angiogram <ul><li>Quickly becoming the test of choice for initial evaluation of a suspected PE. </li></ul><ul><li>CT unlikely to miss any lesion. </li></ul><ul><li>CT has better sensitivity, specificity and can be used directly to screen for PE. </li></ul><ul><li>CT can be used to follow up “non diagnostic V/Q scans. </li></ul>
  14. 14. CT Angiogram <ul><li>Chest computed tomography scanning demonstrating extensive embolization of the pulmonary arteries. </li></ul>
  15. 15. Pulmonary angiogram <ul><li>Gold Standard. </li></ul><ul><li>Positive angiogram provides 100% certainty that an obstruction exists in the pulmonary artery. </li></ul><ul><li>Negative angiogram provides > 90% certainty in the exclusion of PE. </li></ul>
  16. 16. Pulmonary angiogram <ul><li>Left-sided pulmonary angiogram showing extensive filling defects within the left pulmonary artery and its branches. </li></ul>
  17. 17. Summary <ul><li>Plain chest radiograph – Usually normal and non-specific signs. </li></ul><ul><li>Radionuclide ventilation-perfusion lung scan. </li></ul><ul><li>CT Angiography of the pulmonary arteries – Quickly becoming method of choice. </li></ul><ul><li>Pulmonary angiography – Gold standard but invasive. </li></ul>
  18. 19. References <ul><li>Up to date Online. Diagnosis of Acute Pulmonary Embolism. Last revised March 7, 2007. </li></ul><ul><li>Pulmonary Embolism. http://www.e-radiography.net </li></ul>
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×