PD45-12 NEW EXPERIMENTAL MODEL IN RATS FOR PEYRONIE'S DISEASE: CHANGES OF COMPONENTS OF THE EXTRACELLULAR MATRIX

INTRODUCTION AND OBJECTIVES: Why phenotypes of Peyronie’s disease can span from mild fibrotic plaques to severely calcified plaques is poorly understood. Mineralized Peyronie’s plaque represents the most severe manifestation, occurs in a subset of patients, and often requires complex surgical excision and reconstruction. The development of analytical high resolution X-ray microscopy techniques may shed new insights on the pathophysiologic mechanisms on plaque-forming processes. The purpose of this study was to characterize the structure of mineralized Peyronie’s plaque and evaluate its association with the adjacent softer extracellular matrix. METHODS: Surgically excised Peyronie’s plaque using a tunica-sparing approach were imaged using high resolution micro-CT with a spatial resolution of 2 mm. Reconstructed tomograms were used to segment regions of different mineral densities by using intensity differences with Avizo 3D software. RESULTS: A representative figure demonstrates micro-CT imaging demonstrating virtual sections and 3D reconstructions. Mineral density of the plaque ranged from 1000 to 1380 mg/cc and was similar to known mineral density of alveolar bone (1200 mg/cc). The plaque was heterogenous in nature and similar to alveolar bone. Both contain endosteal-like spaces (alveoli) encircled by extracellular matrix of lower mineral densities followed by higher mineral densities in regions farther away from alveoli. Endosteal-like spaces were suggestive of regions containing vasculature. CONCLUSIONS: Calcified Peyronie’s plaque demonstrated heterogeneity both in structure and mineral density. The structure of the pathologic plaque is highly analogous to non-pathologic alveolar bone suggesting shared biomineralization pathways. Understanding the structural and elemental properties of mineralized plaque may help elucidate interventions that can slow or mitigate the ossification process in the tunica albuginea.