Hello and welcome to the Zero to Finals podcast. My name is Tom and in this episode I'm going to be talking to you about autosclerosis. And you can find written notes on this topic at zero definals.com slash autosclerosis or in the ear, nose and throat section of the zero definals surgery book.

So let's get straight into it.

Otosclerosis is a condition where there is remodeling of the small bones in the middle ear,

leading to conductive hearing loss.

Otto refers to ears and sclerosis refers to hardening.

It usually presents before the age of 40 years old.

The development of autosclerosis is thought to be the result of a combination of environmental

and genetic factors, although the exact mechanism is not fully understood.

It can be inherited in an autosomal dominant pattern, however no specific genetic mutations have been

identified. It's more common in women. Let's talk about the pathophysiology. The auditory osicles are the tiny bones in the middle

ear that transmit sound vibrations from the tympanic membrane to the cochlea. They are the

malleus, incus and stapies. The stapies is connected to the oval window or the fenestra ovalis of the cochlea,

where it transmits vibrations into the cochlear. The cochlear converts these vibrations

into sensory signals that the brain interprets as sound. In patients with autosclerosis, these tiny bones in the middle ear are affected by abnormal

bone remodeling and abnormal bone formation.

This mainly affects the base of the stapies where it attaches to the oval window

and causes stiffening and fixation, preventing it from transmitting sound effectively to the oval window and causes stiffening and fixation preventing it from transmitting

sound effectively to the cochlear. It causes conductive hearing loss as opposed to sensory

neural hearing loss. Let's talk about the presentation. The typical presentation is a patient

under 40 years of age presenting with unilateral

or bilateral hearing loss and tinnitus. The hearing loss tends to affect the hearing of lower

pitch sounds more than higher pitch sounds. Female speech may be easier to hear than male speech

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