DOI: 10.1148/radiol.2293021496
Intermittent-Mode CT Fluoroscopy–guided Biopsy of the Lung or Upper Abdomen with Breath-hold Monitoring and Feedback: System Development and Feasibility1
Stephanie K. Carlson, MD,
Joel P. Felmlee, PhD,
Claire E. Bender, MD,
Richard L. Ehman, MD,
Kelly L. Classic, MS,
Houchun H. Hu and
Tanya L. Hoskin, MS
1 From the Department of Radiology (S.K.C., J.P.F., C.E.B., R.L.E., H.H.H.), Section of Safety (K.L.C.), and Division of Biostatistics (T.L.H.), Mayo Clinic, 200 First St SW, Rochester, MN 55905. From the 2002 RSNA scientific assembly. Received November 20, 2002; revision requested January 13, 2003; revision received March 17; accepted April 2. Supported in part by the General Electric–Association of University Radiologists Radiology Research Fellowship Program. Address correspondence to S.K.C. (e-mail: scarlson@mayo.edu).
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Figure 1. Bellows belt consists of a hook and loop band with expandable rubber bellows (arrow) connected by rubber tubing (arrowhead) to a pressure-sensitive transducer (not shown).
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Figure 2. Close-up view of LED breath-hold monitoring and feedback display. Patient attempts to light only the center diode (line) by inhaling or exhaling when instructed. This correlates to the reference breath-hold level established during localization CT.
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Figure 3. Bellows system in place in the CT suite. The patient LED breath-hold monitoring and feedback display (arrow) is mounted on the CT table by using an articulated arm so the patients can continuously monitor their breathing level in any position. Second LED monitor is mounted on the in-room CT fluoroscopy screen (arrowhead) for the radiologist to view.
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Figure 4. Bellows system control unit. Turning the solenoid switch (arrow) off and on during breath holding sets the patient’s reference breath hold at the center diode (line). An LED monitor is attached to the control unit (arrowhead) so that the radiologist can monitor the breath-hold level during localization CT.
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Figure 5. Mechanical body-wall phantom for studies of sensitivity for detection of body-wall motion and of reliability. Bellows belt is wrapped around the phantom (arrow), and a motor (arrowhead) was used to reproduce a range of respiratory amplitudes.
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Figure 6a. Transverse CT images obtained during bellows-assisted biopsy of a small peripheral lung nodule. (a) Initial spiral CT scan obtained without CT fluoroscopy shows 8-mm nodule (arrow) in lateral aspect of the left lower lung. Nodule is percutaneously accessible through a rib interspace at this breath-hold level. (b, c) Intermittent-mode CT fluoroscopic images obtained during consecutive breath-hold attempts show that the patient was able to consistently reproduce the identical breath-hold level throughout the procedure. Biopsy results were consistent with a benign inflammatory nodule.
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Figure 6b. Transverse CT images obtained during bellows-assisted biopsy of a small peripheral lung nodule. (a) Initial spiral CT scan obtained without CT fluoroscopy shows 8-mm nodule (arrow) in lateral aspect of the left lower lung. Nodule is percutaneously accessible through a rib interspace at this breath-hold level. (b, c) Intermittent-mode CT fluoroscopic images obtained during consecutive breath-hold attempts show that the patient was able to consistently reproduce the identical breath-hold level throughout the procedure. Biopsy results were consistent with a benign inflammatory nodule.
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Figure 6c. Transverse CT images obtained during bellows-assisted biopsy of a small peripheral lung nodule. (a) Initial spiral CT scan obtained without CT fluoroscopy shows 8-mm nodule (arrow) in lateral aspect of the left lower lung. Nodule is percutaneously accessible through a rib interspace at this breath-hold level. (b, c) Intermittent-mode CT fluoroscopic images obtained during consecutive breath-hold attempts show that the patient was able to consistently reproduce the identical breath-hold level throughout the procedure. Biopsy results were consistent with a benign inflammatory nodule.
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Figure 7a. Transverse CT images obtained with the patient in the prone position during bellows-assisted biopsy of a pleura-based lung lesion. (a) Initial spiral CT scan obtained for localization purposes shows lesion directly underneath a rib (arrowhead) and not adequately accessible. (b) Second spiral CT scan obtained after patient was instructed to take a deeper inspiration by using the bellows system feedback shows lesion to be accessible (needle is within the lesion). Patient was able to reproduce this exact breath-hold level throughout the procedure, which allowed biopsy of the lesion without traversing lung tissue. Biopsy results were consistent with non-small cell lung cancer.
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Figure 7b. Transverse CT images obtained with the patient in the prone position during bellows-assisted biopsy of a pleura-based lung lesion. (a) Initial spiral CT scan obtained for localization purposes shows lesion directly underneath a rib (arrowhead) and not adequately accessible. (b) Second spiral CT scan obtained after patient was instructed to take a deeper inspiration by using the bellows system feedback shows lesion to be accessible (needle is within the lesion). Patient was able to reproduce this exact breath-hold level throughout the procedure, which allowed biopsy of the lesion without traversing lung tissue. Biopsy results were consistent with non-small cell lung cancer.
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Copyright © 2003 by the Radiological Society of North America.
