CT Fluoroscopy-guided Abdominal Interventions: Techniques, Results, and Radiation Exposure1
Stuart G. Silverman, MD,
Kemal Tuncali, MD,
Douglass F. Adams, MD,
Richard D. Nawfel, MS,
Kelly H. Zou, PhD and
Philip F. Judy, PhD
1 From the Department of Radiology, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115 (S.G.S., K.T., D.F.A., R.D.N., K.H.Z., P.F.J.) and the Department of Health Care Policy, Harvard Medical School, Boston, Mass (K.H.Z.). From the 1998 RSNA scientific assembly. Received November 9, 1998; revision requested January 4, 1999; revision received February 12; accepted March 25. Address reprint requests to S.G.S. (e-mail: silver@ulna.bwh.harvard.edu).
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Figure 1. Photograph of needle holder used during CT fluoroscopy-guided abdominal intervention with use of the real-time method. A towel clamp (arrowhead) is affixed to the needle hub and can be used to direct a needle during real-time CT fluoroscopy such that the operator's hand is 10 cm from the primary x-ray beam.
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Figure 2. Images obtained during CT fluoroscopy-guided biopsy of pancreatic cancer (open arrow) with use of the real-time method. The initial nonfluoroscopic spiral CT scan (upper left) showed a bowel-free path to the target. When CT fluoroscopy began (upper right), the colon (arrowhead) was interposed between the needle (solid arrow) and the target. By using CT fluoroscopic guidance, the needle was placed to the right of the colon, and the colon was deflected to the left (lower left), which allowed the needle to be directed to the pancreatic mass without piercing the colon (lower right).
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Figure 3. Images obtained during the performance of CT fluoroscopy-guided needle aspiration of a pancreatic fluid collection. Initial nonfluoroscopic spiral CT scan (left) showed a large superficial collection (arrowheads). By using the quick-check method, a 3-second scan (right) was used to visualize the needle tip (120 kVp, 50 mA, 10-mm collimation).
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Figure 4. Graph shows that the mean patient doses for each of the 6 monthly periods decreased during the study. To convert rad to SI units (gray), divide by 100.
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Figure 5. Graph shows that the mean CT fluoroscopy times for each of the 6 monthly periods decreased only slightly after an initial increase. CTF = CT fluoroscopy.
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Figure 6. Graph demonstrates the relative distribution of chosen CT parameters for each of the 6 monthly periods and shows the gradual decrease in the use of the higher dose parameter of 120 kVp and 90 mA and the increase in the use of the relatively lower dose parameter of 120 kVp and 50 mA. Black bar = 120 kVp and 50 mA, dotted bar = 80 kVp and 135 mA, gray bar = 120 kVp and 90 mA, and white bar = 80 kVp and 75 mA, 80 kVp and 105 mA, 120 kVp and 70 mA, and 140 kVp and 43 mA.
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Figure 7. Image obtained during CT fluoroscopy-guided biopsy of a liver metastasis with use of the quick-check method. The liver lesion (arrowheads) is visualized well enough to be targeted with use of 80 kVp, 135 mA, and 5-mm collimation.
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Figure 8. Images obtained during CT fluoroscopy-guided needle aspiration of a pelvic hematoma. Initial nonfluoroscopic spiral CT scan (upper left) shows the hematoma (arrowhead) well. However, with use of CT fluoroscopy, the artifact of the pelvic bones prevented adequate visualization of the target at 80 kVp, 75 mA, and 5-mm collimation (upper right). The lesion was targeted successfully with 120 kVp, 50 mA, and 5-mm collimation (lower left and lower right).
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Figure 9. Images obtained during CT fluoroscopy-guided catheter drainage of a pelvic abscess with use of the trocar technique. Initial nonfluoroscopic spiral CT scan (upper left) shows the abscess (arrowhead). With use of CT fluoroscopy, the real-time method (upper right) was used to place the needle, and the quick-check method (lower left) was used to image the catheter (arrow) with the stiffening cannula. Spiral CT scan (lower right) shows complete drainage of the collection.
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Figure 10. Images obtained during CT fluoroscopy-guided catheter drainage of an abscess with use of the Seldinger technique. The quick-check method was used to direct the needle into the abscess (arrowhead; upper left) and confirm appropriate needle, guide wire (upper right, shown with a wider window setting), and catheter (arrow; lower left position). Spiral CT scan (lower right) documents complete drainage.
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Copyright © 1999 by the Radiological Society of North America.
