Paget’s disease interferes with the body’s normal bone re-cycling process in which new bone tissue replaces the old. This can begin to make bones both fragile and misshapen over time. In most cases Paget’s is mainly found in the pelvis, skull, spine and legs. Usually Paget’s disease is asymptomatic however when symptoms do occur they are usually associated with bone pain, hearing loss and a high incidence of tinnitus.
Bone malformities are usually asymmetrical so one of the possible signs of Paget’s disease is an unexplained hearing loss mainly in one ear. The Cochlea is embedded in one of the hardest bones in our body, known as the Petrous (or stone-like) portion of the mastoid process which is the firm lump just behind each ear. In the middle ear behind the eardrum are the three smallest bones in the body, the malleus, incus and stapes. All of these bones can be affected in Paget’s disease. Where the bones or structure of the middle ear are affected patients can develop a conductive hearing loss. This means that sound vibrations in the air that would normally be efficiently transferred to the inner ear by the eardrum and ossicles experiences greater resistance.
This results in less sound energy reaching the inner ear leading to a hearing loss. Unfortunately this resistance acts in both directions meaning internal noises such as chewing, blood pulsing and the patients own voice can seem significantly louder. These body sounds are known as somatosounds and can be a troubling form of tinnitus. Sometimes the path of a vein or artery can be altered leading to a more turbulent blood flow and either a rushing or more pulsatile type of tinnitus. Should the bone holding the Cochlear become affected this can also lead to a hearing loss, usually high frequency.
Any degree of hearing loss can increase susceptibility to the emergence of tinnitus. With Paget’s disease it is not uncommon to present with what is known as a ‘mixed’ hearing loss. This means that part of the hearing loss in conductive and part is ‘sensorineural’ (i.e. inner ear). Complex hearing loss associated with tinnitus requires specialised skill when trying to correct with hearing aids. All Tinnitus UK Audiologists have had specific training on complex loss and understand how this may interact with tinnitus.