STEREOLITHOGRAPHIC (SL) BIOMODELLING IN CRANIOFACIAL SURGERY

Background: Stereolithographic (SL) biomodelling allows 3D CT to be us ed to generate solid plastic replicas of anatomical structures (biomod els). Case reports in the literature suggest that such biomodels may h ave a use in craniofacial surgery but no large series or assessment of utility has been reported. A prospective trial to assess the utility of biomodeiling in craniofacial surgery has been performed. Methods: F orty patients with complex craniofacial abnormalities were selected an d 3D CT scanning performed. The data of interest was used to guide a l aser to selectively polymerise photosensitive resin to manufacture SL biomodels. The biomodels were used for patient education, diagnosis an d operative planning. An assessment protocol was designed to test the hypothesis that biomodels in addition to standard imaging had greater utility in the surgery performed than the standard imaging alone. Resu lts: Anecdotally surgeons found biomodelling useful in 40 complex cran iofacial operations. The formal assessment of the first 10 cases sugge sted biomodels improved operative planning (image 76%, image with bio- model 97%, P < 0.01) and diagnosis (image 82.5%, image with biomodel 9 9.25%, P < 0.01). Surgeons estimated that the use of biomodels had red uced operating time by a mean of 16% and were cost effective at a mean price of $1100 AUS. Conclusion: Biomodelling was reported as an intui tive, user-friendly technology that facilitated diagnosis, operative p lanning and communication between colleagues and patients. Limitations of the technology were manufacturing time and cost.