Accuracy of stereolithographic models of human anatomy

TLDR

Higher accuracy in SLA models can be achieved by using CT images with smaller pixel resolution. The study aimed to assess the dimensional accuracy of anatomical replicas produced from CT images via stereolithography. Researchers scanned a dry bone skull and a geometric phantom, fabricated SLA replicas, and measured distances between anatomical landmarks to compare originals and replicas. SLA replicas exhibited mean errors of 0.47 mm for the phantom (97.7–99.1 % accuracy) and 0.85 mm for the skull, confirming their suitability for pre‑operative planning of complex surgeries.

Abstract

SUMMARY A study was undertaken to determine the dimensional accuracy of anatomical replicas derived from X‐ray 3D computed tomography (CT) images and produced using the rapid prototyping technique of stereolithography (SLA). A dry bone skull and geometric phantom were scanned, and replicas were produced. Distance measurements were obtained to compare the original objects and the resulting replicas. Repeated measurements between anatomical landmarks were used for comparison of the original skull and replica. Results for the geometric phantom demonstrate a mean difference of + 0.47 mm, representing an accuracy of 97.7–99.12%. Measurements of the skull produced a range of absolute differences (maximum +4.62 mm, minimum +0.1 mm, mean +0.85 mm). These results support the use of SLA models of human anatomical structures in such areas as pre‐operative planning of complex surgical procedures. For applications where higher accuracy is required, improvements can be expected by utilizing smaller pixel resolution in the CT images. Stereolithographic models can now be confidently employed as accurate, three‐dimensional replicas of complex, anatomical structures.