Comparison of examination times between CT scanners: are the newer scanners faster?

The purpose of this study was to determine if a newer technology helical CT scanner can reduce CT examination times.

Data from 1049 CT examinations were recorded prospectively during a 5-week period. "Room time" was defined as the time each patient spent in the CT room (time patient exited minus time patient entered) and "scanner time" was defined as the time a scanner was dedicated to a specific patient (longer of either time that image processing was complete minus time patient entered room, or total time that patient spent in the scanner room). Data to calculate the room and scanner times were recorded along with the scanner type, examination protocol, and five other covariates. Both times were calculated for the 10 most common examination protocols (n = 769 patients) and compared between the older and newer model CT scanner using analysis of covariance models. The most common protocols were abdomen and pelvis (n = 211); head (n = 146); chest (n = 99); simple sinus (n = 99); and chest, abdomen, and pelvis (n = 68).

The mean room and scanner times, adjusted for covariates, were both significantly shorter for the newer scanner (p = .0001). The results for room time were statistically significant for six of the 10 examination protocols (84% of examinations). Likewise, the results for scanner time were statistically significant for four examination protocols (68% of examinations). Examination times were longer for inpatients (p = .0001) and when problems occurred during the examination (p = .0001). Sex and age did not significantly affect examination times (p > .08).

The newer helical CT scanner we studied significantly reduced the time for many types of examinations.