Reproducibility and thickness selection in measurement of gastric cancer volume using MSCTLI

Objective To investigate the slice thickness selection of measuring gastric cancer volume using MSCT,and to evaluate the reproducibility of the measurement of gastric cancer volume with MSCT.Methods MSCT image data of 33 patients with gastric cancer were transferred to the workstation.Gastric cancer volume was measured with the slice thickness of 3 mm,5 mm and 7 mm,respectively,and was repeatedly measured with 5 mm slice thickness by another experienced radiologist.Intra-observer and inter-observer variability was calculated.Results Gastric cancer volume measured with slice thickness of 3 mm,5 mm and 7 mm were(65.06±46.87)cm3,(64.74±47.13)cm3 and(63.56±45.82)cm3(F=5.409,P0.05),respectively.Analysis of variance of the repeatedly measured results showed that the differences between 3 mm and 7 mm,5 mm and 7 mm had statistical significance(all P0.05),while the difference between 3 mm and 5 mm had no statistical significance(P=0.298).Interclass correlation coefficient of the slice thickness of 3 mm and 5 mm,3 mm and 7 mm,5 mm and 7 mm in measuring gastric cancer volume were 0.992,0.990,0.988,respectively.Time costed was(30.6±15.5)min,(20.0±11.8)min and(12.3±6.4)min when measured with slice thickness of 3 mm,5 mm and 7 mm,respectively.The gastric cancer volumes measured by two observers with 5 mm slice thickness were(64.74±47.13)cm3 and(65.32±45.82)cm3(F=1.386,P=0.248),respectively.And the interclass correlation coefficient was 0.998.Conclusion It is better to select slice thickness of 3 mm and 5 mm to measure gastric cancer volume using MSCT.Selection of 5 mm slice thickness measuring gastric cancer volume can spare time.Measurement of gastric cancer volume with MSCT is of high consistency and reproducibility and has clinical value.