Are There Cochlear Shunts in Paget's and Recklinghausen's Disease?

Abstract

In 14 petrous bones from 14 cases of Paget's osteitis deformans and Recklinghausen's osteitis fibrosa, foci of diseased bone replace the endosteal layer of the bony otic capsule. The petrous bones demonstrate changes in the stria vascularis in the form of circumscribed swelling and flat thickenings, as described by M. Kornfeld. In contrast to the strial buds in otosclerosis, the strial changes in osteitis deformans and osteitis fibrosa also occur in areas where the normal endosteal layer still remains intact. There is no evidence of shunts in the spiral ligament of any of these temporal bones to cause the changes in the stria. Also, no new lamellar bone deposits could be seen at the attachment of the spiral ligament. On the other hand, in 8 petrous bones with Paget's and Recklinghausen's disease there are several slender shunts in the basal turn of the cochlea, connecting the capillaries of the diseased bone with the spiral veins. In these cases, however, in only one case are there signs of venous congestion in the inner ear. In 15 petrous bones with osteitis deformans and osteitis fibrosa large shunts are seen in the internal auditory meatus between the vessels of the diseased bone lining the meatus and the internal auditory vessels within the canal. A marked thickening of the endosteal connective tissue provides evidence of venous congestion in the internal auditory meatus, due to the shunts. These shunts, causing a circulatory disturbance in the internal auditory meatus, may be responsible for the sensorineural deafness in Paget's and Recklinghausen's disease.