Computed tomography slice thickness and its effects on three-dimensional reconstruction of anatomical structures

• CT scan parameters have a direct impact on resultant 3D models.
• Analyses were conducted to quantify differences in 3D models from different slice thicknesses.
• Higher slice thickness yields to loss of detail in resultant models.
• It is suggested that a maximum 1.25 mm slice thickness be used for 3D modeling.

ObjectivesComputed Tomography (CT) scan parameters such as slice thickness have a direct impact on any 3D models derived from the volumetric data. Higher slice thickness spacing leads to loss of resolution quality in the visualizations.Materials and methodsTwenty CT head scans were acquired at a 0.625 mm slice thickness. These data sets were resliced a range of 1–5 mm slice thicknesses. The resultant 3D models of the skull were compared using the 0.625 mm model as a standard. Differences in surface area, volume and part-to-part comparison were analyzed.Results and conclusionsThere were significant differences in surface area, volume and part-to-part comparison analyses from the 0.625 mm skulls as determined with One-way ANOVA by a p-value less than 0.05. Part-to-part comparison proved to have the greatest sensitivity for detecting geometric differences between slice thickness treatments. This study proposes using a 1.25 mm maximum slice thickness when forensic practitioners require 3D reconstruction in their casework.