Detection of pulmonary metastases with pathological correlation: effect of breathing on the accuracy of spiral CT.
BACKGROUND
CT of the chest for suspected pulmonary metastases in adults is generally performed using a breath-hold technique. The results may not be applicable to young children in whom breath-holding may be impossible.


OBJECTIVE
Determine the effect of breathing on the accuracy of pulmonary metastasis detection by spiral CT (SCT).


METHODS
Prior to euthanasia four anesthetized dogs with metastatic osteosarcoma underwent SCT with a collimation of 5 mm and a pitch of 2, during both induced breath-hold and normal quiet breathing. Images were reconstructed as contiguous 5-mm slices. Macroscopically evident metastases were noted at postmortem. Hard-copy SCT images were reviewed by ten radiologists, each of whom circled all suspected metastases. SCT images were compared with postmortem results to determine true and false positives.


RESULTS
The pathologist identified 132 macroscopically evident pulmonary metastases. For metastasis detection, there was no significant difference between breath-hold SCT and breathing SCT.


CONCLUSIONS
In our animal model, SCT can be performed during normal resting breathing without significant loss of accuracy in the detection of pulmonary metastases.
Coakley
F V
FV
Abdominal Imaging Section, Department of Radiology, University of California San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628, USA.
Cohen
M D
MD
Waters
D J
DJ
Davis
M M
MM
Karmazyn
B
B
Gonin
R
R
Hanna
M P
MP
D000818:Animals; D001859:Bone Neoplasms / Q000473:pathology; D004285:Dogs; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000556:secondary*; D012516:Osteosarcoma / Q000000981:diagnostic imaging* / Q000473:pathology / Q000556:secondary*; D012119:Respiration; D014057:Tomography, X-Ray Computed / Q000379:methods