Opportunistic bone mineral density assessment in pediatric scoliosis: validating Hounsfield unit measurement from lumbar CT images.
Standard pelvis-parallel CT scans lose bone density reliability with greater spinal tilt
Opportunistic bone mineral density assessment in pediatric scoliosis: validating Hounsfield unit measurement from lumbar CT images.
Hounsfield Units (Hounsfield Units) derived from CT scans are a promising bone mineral density surrogate in pediatrics, yet their reliability in patients with scoliosis and significant lumbar tilt remains unknown.
We investigated the reliability of Hounsfield Units measurements in adolescent idiopathic scoliosis (adolescent idiopathic scoliosis), particularly addressing the impact of spinal tilt.
We retrospectively reviewed lumbar CT images of 11- to 19-year-old adolescent idiopathic scoliosis patients who underwent posterior spinal fusion (July 2007-March 2024).
Large bone density measurement errors were about twice as common with higher spinal tilt (11.3% vs 5.6%)
Both intra-rater (ICC(1,1) > 0.95) and inter-rater (ICC(2,1) > 0.80) reliability were excellent.
Measurements from standard pelvis-parallel images and reconstructed images showed stable overall equivalence (ICC(3,1) = 0.96).
Our analyses for adolescent idiopathic scoliosis patients showed that vertebral Hounsfield Units measurements are reliable when using vertebral-parallel reconstructed images but standard pelvis-parallel images lose reliability with significant tilt.
While our findings do not promote routine CT usage, our validated methodology provides a baseline technique that could potentially be applied to complex, high-risk cases where osteoporosis is prevalent and critical for surgical planning.