TABLE 2

Technical factors that may affect volume measurement

 Effects on volumetry Section thickness Volume overestimation with thick sections [40, 68, 69, 86–89] Overlapping reconstruction Volume overestimation with non-overlapping sections [90, 91] Pitch Low accuracy with high pitch mode [92] Reconstruction algorithms Easier nodule sampling with high spatial frequency algorithms [86, 89, 91, 93]Volume overestimation with high spatial frequency algorithms [90, 94, 95] Intravenous contrast medium Volume overestimation [95–97] Scanner type Differences in volume estimation [50, 86, 98]Higher accuracy with helical CT scanner [98] Low radiation dose Low accuracy [76, 99, 100] Iterative reconstruction Better performance [101–112] Manual versus semi/automated method Reduced observer variability with automated system [113, 114]Manual interaction reduces bias due to the software performance [55, 115] Software and algorithms package Differences in volume estimation [57, 67, 116–118]

CT: computed tomography.