Statistical Shape Modelling of the Nasosinusal Anatomy

Michele Bertolini; Silvia Tonghini; Marco Rossoni; Marina Carulli; Susanne Weise; Christian Jan Baldus; Giorgio Colombo; Monica Bordegoni

arXiv · 2510.09713

Statistical Shape Modelling of the Nasosinusal Anatomy

Michele Bertolini·Silvia Tonghini·Marco Rossoni·Marina Carulli·Susanne Weise·Christian Jan Baldus·Giorgio Colombo·Monica Bordegoni

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Abstract

The human nose exhibits a huge variation in shape among individuals. All these variants alter the airflow through the nasal cavity and can impact how we smell odors. To acquire a better understanding of physiological and pathological functioning, it is important to study the effects of these modifications. SSM, or Statistical Shape Modelling, is a widely used methodology for considering morphological differences within a population. In the literature, only a few studies analyze nasal anatomy in its entirety, including paranasal sinuses, whose segmentation is particularly challenging due to their complexity and variability. This work aims at creating a highly accurate SSM for the nasosinusal complex. A traditional, greyscale thresholding-based segmentation approach was chosen, relying on Mimics software (Leuven, Belgium). 40 computed tomography (CT) datasets were considered. After segmentation, post-processing was performed to obtain watertight meshes using 3-Matic software (Leuven, Belgium), which was also used for the SSM generation. The generated model shows all relevant landmarks that typically characterize a nasosinual complex. 32 different modes are needed to explain 95% of the total variance. As a preliminary output, this study showed the feasibility and consistency of a statistical model of the nasosinusal anatomy. However, additional studies involving a larger sample size and a more robust validation process could be conducted.

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Michele Bertolini, Silvia Tonghini, Marco Rossoni, Marina Carulli, Susanne Weise, Christian Jan Baldus, Giorgio Colombo, Monica Bordegoni. 2025-10-10. Statistical Shape Modelling of the Nasosinusal Anatomy. https://arxiv.org/abs/2510.09713

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