Original report - Dose and pitch relationship for a particular multislice CT scanner

OBJECTIVE. With single-slice helical CT, an increased pitch can decrease th e radiation dose to the patient if all other parameters are constant. The p urpose of this study was to determine whether the same relationship holds f or a particular multislice helical CT system (Somatom Plus 4 VZ multislice helical CT scanner, version Al IA) in our department. CONCLUSION. The measured. radiation dose to the phantom was identical for a ll pitch selections on the multislice helical CT system we tested. This une xpected result was because of an automatic proportionate increase in the tu be current when the pitch selection was increased. Radiologists and physici sts should exercise caution when extrapolating dose reduction strategies fr om single-slice to multislice helical CT systems, and they must acquire a d etailed understanding of the multislice helical CT scanner of their chosen manufacturer.