Low Dose Helical CT Screening for Lung Cancer:
The effective radiation dose associated with the low dose screening exam is 0.65 mSv. The approximate dose for conventional CT is 5.8 mSv.
Helical CT: Mayo clinic
Non-contrast exam
7 mm collimation
Pitch 2:1
120 kVp
80 mA
Reconstruct images at 3.5 mm spacing
Helical CT: Henschke CI
Non-contrast exam multidetector camera
2.5 mm collimation
Pitch 1.5
120 kVp
40 mA
Acquire exam in single breath hold (15-20 sec) following hyperventilation
Multislice CT:
High speed mode
5 mm collimation
Table feed 30 mm/sec
120 kVp
40 mA
Reconstruct images at 3.5 mm spacing
REFERENCES:
Society of Thoracic Radiology Course Syllabus 2000; Swenson SJ. Lung cancer screening: Low dose CT. 32-36
Radiology 2004; Henschke CI, et al. C screening for lung cancer:
suspiciousness of nodules according to size on baseline scans. 231: 164-168