Fifth Stage
E.N.T
Dr. Mushtaq – Lecture 5
1
Hearing loss
A full or partial decrease in the ability to detect or understand sounds .
Types:
•
Conductive.
•
Seneorineural.
•
Mixed.
Conductive hearing loss
Causes:
A. External ear conduction ;
1. Wax
2. F.B.
3. Inflammatory swelling
4. Artesia
5. tumor
B. Tympanic membrane condition
1- perforation
2- myringitis bullosa haemorrhagica
C- middle ear:
1. Haemotympanum
2. Ossicular chain dislocation
3. Baratrauma
4. O.m.
5. O.m. / effusion
6. Otosclerosis
7. Tumour
8. Eust. Tube dysf.
Otosclerosis
•
Autosomal dominant / unknown etiology
•
Patho; absorption of normal bone & replacement by vascular spongy osteoid
tissue which become thicker later on
•
The most common site is promontory/ Anterior margin of oval window.
•
Stapes ankylosed in advanced cases
2
Clinical features
•
Female
•
18-30 yrs
•
50% +ve family history
•
Gradually increasing hearing difficulty & tinnitus are the main symptoms
•
Hearing better in noisy surrounding( paracusis willisii)
•
Speak in low tone voice.
Examination:
•
Normal otoscopical ex. Unless in early stage , flamingo ting appearance
•
Hearing assessment reveals CHL.
Treatment
•
Hearing aids
•
stapedectomy
Sensorineural hearing loss
•
SNHL is due to insensitivity of the inner ear or to impairment in the function of the
auditory nervous
Causes:
1. Vascular: e.g; arterial occlusion ,
thrombosis of the internal auditory n.,
thrombocytopenia , SCA.
2. Inflammatory disease e.g;
- measles , mump , meningitis,
syphilis , AIDS chlamydial inf. /infected mother
3. Immune complex dis. ; rh. Arth.
4. Neoplasm e,g; vestibular schwannoma
5. Noise induced hearing loss / 4kH dip
6. Degenerative / presbyacusis
7. Iatrogenic causes / ototoxic drugs e.g;
* aminoglycosides
* cytotoxic drugs
3
* aspirin , frusamide , ciprofloxacin >>> revesible
8. Congenital / waardenburg syndrome ,
pendred syndrome
9. Trauma h. inj. Surgery, loud sound
10.
Miscellaneous
- M.S.
- DM.
- meniere`s dis.
- cochlear otosclerosis
Thank you,,,