Ossicular deformity

Introduction Congenital ossicular chain malformation is caused by embryonic developmental disorders caused by morphological distortion or loss of the hammer bone, the anvil and the tibia, resulting in a vocal paralysis. Congenital external auditory canal atresia is often accompanied by ossicular deformity.

Cause

The ossicular chain consists of the malleus, the anvil and the tibia, and the origin of their embryos remains controversial.

One view is that the malleus and the anvil are from the interstitial of the first zygomatic arch, and the tibia is from the interstitial of the second zygomatic arch. The formation of the tibial floor and the oval window is closely related to the development of the ear capsule; A newer view is that the hammer bone and the anvil bone (including the anvil short) originate from the interstitial of the first zygomatic arch, the hammer shank, the long foot of the anvil, and the sacral slab structure from the second zygomatic arch . A certain tibia dysplasia can cause a deformity of a group of osseointegrations of the zygomatic arch, and a group of osseointegrations originating from another zygomatic arch is normal. According to this point, the latter view is more clinically visible. Two types of ossicular deformities.

an examination

Related inspection

Cochlear electrogram, Otolaryngology, CT examination

Clinical manifestations:

The main symptoms of the first type of ossicular deformity are deafness, most of which are unilateral, electrical sounding and hearing sputum, and impedance sensing has two opposite results. If the ossicular chain is interrupted due to a shortage of ossicular bone, it is characterized by high fluency; the ossicular chain is basically intact and fixed by the humeral foot plate (or fused with the oval window), which is low-sounding, both The diaphragmatic muscles may disappear or weaken, and the external auditory canal and tympanic membrane are normal. Individual patients may have mild deformities such as narrowing of the ear canal, thickening of the eardrum, or disappearance of the auricle (especially the upper part).

The second type of malformation is also a vocal sputum. The impedance measurement shown by the tympanic cavity on the hammer anvil is low-sounding, the tympanic membrane is somewhat indented, the tension is normal, and the hammer stalk loses normal inclination and is dull. The cone appears.

Differential diagnosis

Ear bone valgus: It is a less common phenomenon. It shows that the second row of ear bones from the outside to the inside is more prominent. The surface is not very good-looking, but it is harmless to the human body. It is generally formed innate. It is manifested by the fact that the second row of ear bones is more prominent from the outside to the inside.

Ear augmentation: Patients with Barth Syndrome have a special face, large head, prominent forehead, face with triangular auricles, large eyes, and drooping mouth. The clinical manifestations of this disease are complex and diverse, with hypokalemia symptoms. During the fetal period, Bartter syndrome is characterized by intermittent episodes of polyuria. During the 22-24 weeks of pregnancy, there is too much amniotic fluid. It is necessary to repeatedly take amniotic fluid to prevent premature birth.

Otosclerosis: It is an unexplained disease. It is pathologically due to the primary localized bone resorption of bone labyrinth, and it is called "hardening" on behalf of the vascular-rich spongy bone hyperplasia. When invading the egg garden window, it can cause the humerus to be fixed, lose the sound transmission function, and make the hearing progressively decline. The incidence of otosclerosis has a lot to do with human races. The incidence of whites is high, the incidence of blacks is the lowest, and the yellows are somewhere in between. The age of onset is more and more young and middle-aged.

Auricular dysplasia: one of the symptoms of Digeol's syndrome in children. Facial features of children with Digolger syndrome include long face, spherical tip and narrow nose, cleft palate, flattened humerus, widened eye distance, squint, low lop ear with earring depression and auricular dysplasia and mandible too small.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.