Otosclerosis of the incus

The Stapes in Otosclerosis: Osteoarthritis of an Ear Ossicle

Otosclerosis is a pagetoid proliferation of bone remodeling, vascular proliferation, bone resorption and new bone formation in the tympanic region of the temporal bone. The resulting anklyosis of the stapes footplate as it articulates with the oval window is the most common cause of conductive hearing loss in young to middle aged, predominantly Caucasian individuals. The characteristic histologic features have been well documented by autopsy studies of the temporal bone. Although stapedectomy is the surgical treatment for otosclerosis, the stapes specimen may be submitted for gross examination only or not examined at all. A retrospective study of 73 stapedectomy specimens (2008-2019) not including the stapes footplate. Clinical features from the electronic medical record as well as standard histologic sections from surgical specimens were reviewed. Neither the stapedal head nor crura showed histologic features of otosclerosis. There was mild osteoarthritis affecting the head, possibly as a consequence of persistent ossicular vibration superimposed on the ankylosed rigidity. The most common changes were surface fissuring (65%), cartilaginous erosion (49%) and irregularity of the osteochondral interface (51%). An occasional osteophyte (8%) was observed. The ear ossicles, embryologically analogous to long bones of the extremities, develop via endochondral ossification and exhibit articular surfaces of hyaline cartilage. The present observations suggest that a consequence of otosclerotic ankylosis is osteoarthritis of the stapedal head. In this study, the histological features could not be correlated with the severity of hearing loss or duration of clinical disease.

Anatomopathology of the superstructure of the stapes in patients with otosclerosis

Introduction Otosclerosis is a disease that causes bone resorption and deposition in the auditory structures, leading to deafness. Many studies have evaluated the histopathology of the stapes footplate in this disease (osteoblasts, osteoclasts, vascular proliferation, fibroblasts, and histiocytes), but we found no studies in the literature involving the histology of the superstructure of the stapes.

Objectives To perform an analysis under optical microscopy of histopathologic findings of the superstructure of the stapes from patients with otosclerosis.

Methods A contemporary cross-sectional cohort study of pathology analysis of superstructures of the stapes of patients with otosclerosis.

Results Fifteen superstructures of stapes in patients with otosclerosis operated in our service and four stapes of cadavers used for dissection (controls) were evaluated. No areas of bone resorption or deposition or presence of osteoclasts and osteoblasts in the superstructure of the stapes were found. However, we found in the more distal portions of the crura areas with prominent cementitious lines and woven bone, which was different than the mature trabecular bone found in the head of the stapes or in the controls.

Conclusion There were histologic changes in the superstructure of the stapes in patients with otosclerosis operated in our service.

Isolated otosclerosis of the incus in a Korean woman

We report an isolated otosclerosis of the incus that was removed using a transcanal approach and the ossicular chain was reconstructed using a total ossicular replacement prosthesis due to a tilted stapes.