Pathogenesis (development of disease)
The exact pathogenesis of hearing loss is unclear; therefore, it is referred to as acute idiopathic sensorineural hearing loss. Suspected causes of hearing loss are:
- Rheologic regulatory disorders (disturbances in the flow properties of the blood).
- Vascular regulatory disorders/circulatory disorders (vascular regulatory disorders; microemboli (occlusion of small blood vessels by an embolus/vascular plug); venous stasis/stasis).
- Ion channel dysfunction (such as endolymphatic hydrops/increased appearance of water or serous fluid, respectively).
- Immunological processes (such as by neurotropic (“acting on the nervous system“) viruses).
Etiology (causes)
Behavioral causes
- Pleasure food consumption
- Tobacco (smoking)
- Psycho-social situation
- Psychological stress
- Stress
Causes related to disease
- Acoustic neuroma (AKN) – benign tumor arising from Schwann’s cells of the vestibular portion of the VIII. Cranial Nerve, the auditory and vestibular nerves (vestibulocochlear nerve), and is located in the cerebellopontine angle or internal auditory canal. Acoustic neuroma is the most common cerebellopontine angle tumor. More than 95% of all AKNs are unilateral. In contrast, in the presence of neurofibromatosis type 2, acoustic neuroma typically occurs bilaterally.
- Vertebral artery insufficiency – inability of the vertebral artery to pump sufficient blood to the ear.
- Lyme disease – bacterial infection transmitted by ticks.
- Cholesteatoma (synonym: pearl tumor) of the ear – ingrowth of multilayer keratinizing squamous epithelium in the middle ear with subsequent chronic purulent inflammation of the middle ear.
- Diabetes mellitus
- Hemorrhage – for example, during therapy with anticoagulants (anticoagulant drugs such as phenprocoumon).
- Herpes zoster (shingles)
- Heart disease that leads to impaired performance, such as heart failure (cardiac insufficiency).
- Cervical spine disorders – changes in the cervical spine.
- Inner ear embolism – occlusion of an artery supplying the inner ear with resulting reduced supply.
- Perilymph fistula – displacement of inner ear fluid into the middle ear occurring due to injury to the boundary between the inner and middle ear.
- Paraneoplastic causes (in about 2% of cases).
- Sudden drop in blood pressure
- Base of skull fracture
- Sludge phenomenon – clumping of blood due to blood viscosity disorders.
- Vasomotor disorders – disturbances in the regulation of vascular width.
- Viral infections (in about 13% of cases) such as meningitis, syphilis (lues), HIV.
Laboratory diagnoses – laboratory parameters that are considered independent risk factors.
- Hyperlipidemia (lipid metabolism disorder) – esp. hypertriglyceridemia (lipid metabolism disorder with elevation of triacylglycerides (triglycerides) in the blood).
- Hyperuricemia (increase in uric acid levels in the blood).
Environmental pollution – intoxications (poisoning).
- Explosion trauma, blast trauma
Idiopathic hearing loss is present in approximately 70% of cases!
