A Unique Clinical Case of Heterotopic Ossification Volume Reduction in a Child with Fibrodysplasia Ossificans Progressiva Based on Whole-Body Multislice Computed Tomography

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare genetic disorder inherited in an autosomal dominant manner. The FOP development is caused by a mutation in the ACVR1 gene, which encodes a receptor for bone morphogenetic protein, leading to uncontrolled formation of heterotopic ossifications (HO) and causing complete immobility of the patient. Low-dose multislice computed tomography (LDCT) is considered a “gold standard” for assessing the localization and extent of HO lesions. In addition to its high spatial resolution, LDCT combined with specialized software enables quantitative volumetric measurement of HO areas, which can be extremely valuable for monitoring disease progression. We present a clinical case of FOP in a 2-year-old child, for whom whole-body LDCT was performed for the first time in the Russian Federation, followed by calculation of the total HO volume visualized during examination using integrated software tools.

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