The accuracy of ventricular volume measurement and the optimal slice thickness by using multislice helical computed tomography

Abstract

Objective To determine the optimal slice thickness for ventricular volume measurement by tomographic multislice Simpson′s method and to evaluate the accuracy of ventricular volume measured by multislice helical computed tomography (MSCT) in human ventricular casts. Methods Fourteen human left ventricular (LV) and 15 right ventricular (RV) casts were scanned with MSCT scanner by using a scanning protocol similar to clinical practice. A series of LV and RV short-axis images were reconstructed with slice thickness of 2 mm, 3.5 mm, 5 mm, 7 mm, and 10 mm, respectively. Multislice Simpson′s method was used to calculate LV and RV volumes and true cast volume was determined by water displacement. Results The true LV and RV volumes were (55.57±28.91) ml, and (64.23±24.51) ml, respectively. The calculated volumes from different slice thickness ranged from (58.78±28.93) ml to (68.15±32.57) ml for LV casts, and (74.45±27.81) ml to (88.14±32.91) ml for RV casts, respectively. Both the calculated LV and RV volumes correlated closely with the corresponding true volumes [JP2](all r0.95, P0.001), but overestimated the corresponding true volume by (3.21±5.95) to (12.58±[JP]8.56) ml for LV and (10.22±8.45) to (23.91±12.24) ml for RV (all P0.01). There was a close correlation between the overestimation and the selected slice thickness for both LV and RV volume measurements (r=0.998 and 0.996, P0.001). However, when slice thickness was reduced to 5.0 mm, the overestimation became nonsignificant for slice thickness through 2.0 mm to 5.0 mm, and also for both LV and RV volume measurements. Conclusion Both LV and RV volumes can be accurately calculated with MSCT. A 5 mm slice thickness is enough and most efficient for accurate measurement of LV and RV volume.