Using midfacial CT to design patient-matched, 3D printed nasal splints: a retrospective study

Background: Skin cancers on the nose are common in Australia and are often reconstructed with a full-thickness skin graft. Skin grafts on the nasal alar are prone to failure. We hypothesise that this is due to the mobility of the alar and we believe that patient-matched intranasal splints have the potential to support the alar during graft healing and improve graft take. This study aims to characterise nasal morphology in southeast Queenslanders affected by skin cancers, define the input modalities required to design patient-matched intranasal splints, and establish the workflow for the manufacture of these splints. Methods: A series of 200 computed tomography (CT) scans were investigated and segmented into 3D models. They were then classified into groups according to nostril shape using a modified system derived from the literature. Statistical shape modelling was applied to each group to generate a design envelope of noses representative of our cohort. Results: Participants were aged 16–97 years. A design envelope of six nose shapes was generated. These six nose shapes will be used as a basis to design and create patient-matched intranasal splints that will stabilise the nasal alar with the intention of improving graft take. Conclusion: This study demonstrates that statistical shape models can be generated for a given nasal morphology known to be common in a target population. The results of this study will be used to support a future randomised controlled trial testing the safety, tolerability and efficacy of these nasal splints.