Imaging Features Characterizing the Continuum of Diffuse Idiopathic Skeletal Hyperostosis
Abstract
Problem: Diffuse idiopathic skeletal hyperostosis (DISH) is a common musculoskeletal condition yet its etiology, early and progressive disease features, and clinical implications are poorly understood. The purpose of this dissertation was to investigate the imaging features associated with the continuum of DISH.
Methods: A retrospective study design was used to evaluate thoracic computed tomography scans from a population in Minnesota, United States. Female and male individuals ≥20 years of age were examined for imaging features of DISH and early-phase DISH. The extent of ectopic bridging between each vertebrae was scored. Subsequently, the individuals with repeated computed tomography scans of the thoracic spine were evaluated for changes in imaging features over time. Lastly, a cohort of cadaveric human thoracic vertebral column specimens were studied to characterize pathological mineralization of the costovertebral joint (CVJ) and its association with DISH.
Findings: DISH was detected in 14.2% of the sample (7.4% of females, 20.9% of males, average age of 78 years) and early-phase DISH was detected in 13.2% of the sample (10.4% of females, 15.8% of males, average age 73 years). The change to early-phase DISH was characterized by new ectopic bridging at previously unaffected regions. Progression in the severity of DISH was characterized by increased bridge scores in regions that were previously affected. Microcomputed tomography demonstrated that ectopic bridging of the CVJ was associated with DISH and intra-articular CVJ mineralization was associated with early-phase DISH.
Significance: Insight into clinical implications of DISH were uncovered through our population-based research. We reported that DISH or early-phase DISH are present in one out of three individuals over the age of 40, with increased prevalence of DISH among males of advanced age. Importantly, we reported on the spatiotemporal changes across the continuum of DISH that differ based on the stage of development. We also identified a potential link between DISH and CVJ mineralization, which may contribute to a modified diagnostic criteria to improve clinical detection. These findings may facilitate improved detection and reporting of DISH in the clinic and, in turn, enhance clinical outcomes for people living with DISH.