Hearing Loss, Tinnitus and Meniere’s Disease

1. Hearing Loss, Tinnitus and Meniere’s Disease Harold N. Hollander, DO. FAAO-HNS Comprehensive Ear, Nose and Throat, PC.

3. Anatomy and Physiology • Hearing is the complex interplay of three different components • The Sound Conducting System • The Sensory Organs • The Neural Pathways

4. Anatomy and Physiology • The Sound Conducting System • Where sound energy from the external world is transmitted to the middle ear and amplified • The External Ear • Pinna and External Canal • The Middle Ear • Tympanic Membrane (ear drum) • Ossicles (bones of hearing)

5. Anatomy and Physiology • Ear Anatomy

6. Anatomy and Physiology • Sound Transmission Pathway

7. Anatomy and Physiology • Ossicular Amplifier System

8. Anatomy and Physiology • The Sensory Organs • Where mechanical sound energy is converted to electrical nerve energy • Inner Ear • Cochlea • Organ of hearing • Semicircular Canals • Organ of balance

9. Anatomy and Physiology • Inner Ear

10. Anatomy and Physiology • Amplified sound energy enters the Inner Ear and creates fluid waves • These fluid waves are transmitted to the Cochlea – the organ of hearing • The fluid waves deflect and move the Cochlear Hair Cells which change the mechanical fluid wave into millions of electrical nerve signals

11. Anatomy and Physiology • Electron Microgram of Cochlea

12. Anatomy and Physiology • Cochlear Hair Cells

13. Anatomy and Physiology • The Neural Pathways • Cranial Nerve VIII • The Vestibulocochlear Nerve • Cochlear branch combines all the information from the millions of hair cells into a complex single signal • The Pons • Information from both ears is sorted out • The Midbrain • Nerve pathways are directed to the correct cerebral hemisphere • The Cerebral Cortex • The processing centers of the auditory pathway • Where electrical nerve signals are interpreted

14. Anatomy and Physiology • Cranial Nerve VII and Central Auditory Pathways Cochlea and Hair Cells Cranial N. VIII

16. Types of Hearing Loss • Conductive Hearing Loss • Poor Sound Transmission • Sensorineural Hearing Loss • Poor cochlear or nerve function • Mixed Hearing Loss • Components of both conductive and sensorineural hearing loss

17. Types of Hearing Loss • Hearing Can Be Lost At Any Point Along This Pathway!

19. Tinnitus • Definition: The perception of sound in the absence of external stimuli. • Includes ringing, whining, buzzing, roaring, clicking or pulsatile sounds • May be perceived as unilateral (one ear), bilateral (both ears) or nonlocalized. • Estimated 40 million Americans affected with 10 million at a “severe” level • Most common in 40 to 70 years of age

20. Tinnitus • There are a multitude of reasons for the various types of tinnitus! • Pulsatile tinnitus • Transmission from Carotid artery disease or heart murmurs • Abnormal vascular lesions in the head and neck • Tumors • A-V malformations • Brain aneurisms • Benign Intracranial Hypertension

21. Tinnitus • There are a multitude of reasons for the various types of tinnitus! • Pulsatile tinnitus • Muscular causes • Palatal myoclonus • Tensor tympani spasm • Dehiscent Carotid artery in the middle ear • Large or dehiscent Internal Jugular Bulb in the middle ear • Severe hypertension

22. Tinnitus • There are a multitude of reasons for the various types of tinnitus! • Drug or diet related tinnitus • NSAIDS (all aspirin-like products) • Stimulants of any sort • Nasal decongestants or diet pills • Thyroid medicine • Herbals • Caffeine

23. Tinnitus • There are a multitude of reasons for the various types of tinnitus! • Conductive Hearing Loss • Cerumen (wax) impaction • Middle ear effusion (fluid) • Poor Signal to Noise Ratio • Similar to a poor quality stereo system • Higher than average electrical noise in the cochlear amplifier • Psychiatric Tinnitus

24. Tinnitus • There are a multitude of reasons for the various types of tinnitus! • Sensorineural Hearing Loss • The most common cause for tinnitus • Presbycusis ( the hearing loss of aging) • We believe that this may be caused by gradually decreasing blood flow to the cochlear hair cells resulting in loss of the normal electrical actions. • It is also possible that the cochlear hair cells simply have a certain life expectancy and begin to degenerate as some people age. • In general, tinnitus is the result of spurious electrical signals produced by diseased or degenerated cochlear hair cells. The brain interprets these signals as tinnitus.

25. Tinnitus • There are a multitude of reasons for the various types of tinnitus! • Noise Induced Sensorineural Hearing Loss • The second most common cause for tinnitus • The result of severe noise exposure • Long-term exposure (manufacturing and loud music) • Short-term exposure – single episodes of repeated exposure (loud concerts, gun shots, military service, fireworks, auto racing, chain saws) • The noise exposure results in injury to the cochlear hair cells. We believe that the hair cells do not die, but are damaged causing production of spurious neuro-electrical signals that the brain interprets as tinnitus.

26. Tinnitus • Noise Induced Sensorineural Hearing Loss Is Entirely Preventable! Hearing protection must be used • Unfortunately, this type of hearing loss is becoming much more common in children due to headphone use with loud music. • It is expected that within the next 20 years the number of young adults suffering from noise induced tinnitus will grow exponentially.

27. Tinnitus Treatments • Unfortunately, there is no way to directly eliminate tinnitus unless it is related to specific medical conditions • If a specific underlying cause can be found, corrective treatment can be very successful.

28. Tinnitus Treatments • Medicines • IV Lidocaine (local anesthetic that blocks nerve impulses) has worked , but cannot be used on a normal basis. • Tocainamide (oral form of Lidocaine) has not been shown to be effective. • Various antidepressants have been used with occasional, but inconsistent success. • Benzodiazapines (like Valium or Xanax) are effective in up to 75% of patients, but the effect reduces with prolonged use. The risk of dependency is great, and long term use is not recommended.

29. Tinnitus Treatments • Medicines • Several “seizure control” medications are occasionally used, but with limited, occasional success. • Ginko Biloba extract t 120-160mg per day has been shown to be effective in some trials and not in others. • Inclusive evidence of effectiveness with more research to be done • High-dose vitamin treatments have not been shown to be effective in any controlled study.

30. Tinnitus Treatments • Hearing Aids • Amplification of background sounds above the perceived level of tinnitus can be very effective during the day. • If the tinnitus keeps the patient up at night this is a serious problem • Masking with either a white noise generator, fan or programmed sound machine can be quite effective and is easy for bed partners to adjust to. • TV or radio noise is not as effective and promotes poor sleep hygiene.

31. Tinnitus Treatments • Surgery • The use of Cochlear nerve section (cutting) has been reported. This results in deafness and is not effective in patients whose tinnitus is not related to the inner ear itself. Not an accepted treatment. • Biofeedback • Hypnosis • Electrical or magnetic brain or cochlear stimulation • Accupuncture • All these treatments work for a small portion of patients, but have never been shown to be effective for the general population in any well controlled study. • Continued research is ongoing.

33. Meniere’s Disease • First described in 1861 by Prosper Meniere • In 1935 studies of dissected human temporal bones demonstrated that “endolympatic hydrops” was present in the vast majority of affected patients.

34. Meniere’s Disease • The criteria below Must Be Met • Fluctuating sensorineural hearing loss • Fluctuating ear fullness • Fluctuating vertigo • Fluctuating tinnitus • Frequently misdiagnosed / over diagnosed • May be more frequent in women • Probably not hereditary

35. Meniere’s Disease • The Cochlea is divided into 3 chambers with thin membranes dividing them. • The 2 outer chambers are filled with Perilymph which is like Cerebrospinal Fluid that the brain is bathed in. • The inner chamber is filled with Endolymph which is like the fluid found inside the body’s cells. Perilymph Endolymph Perilymph

36. Meniere’s Disease • Most otolaryngologists believe that Meniere’s Disease is the result of Endolymphatic Hydrops. (too much endolymph pressure in comparison to perilymph) • Abnormal pressure/fluid dynamics in the cochlea Normal fluid balanceDilated Scala Media

37. Meniere’s Disease • Many otolaryngologists believe that the increased pressure with Endolymphatic Hydrops may result in micro-ruptures of the Membranous Labyrinth. • Ruptures have been seen in dissected and microscopically examined temporal bones in patients with Meniere’s Disease. • This may be the reason for the episodic nature of the Meniere’s attacks • Healing of these ruptures may account for the return of hearing and balance between episodes. Membranous Labyrinth Ruptures

38. Meniere’s Disease • We truly do not know why the apparent endolymphatic hydrops is present. • Obstruction of the Endolymphatic Duct or Sac? (the area where excess Endolymph is absorbed) • Increased production of Endolymph? • Poor absorption of normally produced Endolymph? • Some have suggested that allergies may play a role • No convincing objective evidence to support any of these theories.

39. Meniere’s Disease Treatments • Accurate diagnosis • Reduced salt diet • May reduce fluid shifts in the inner ear • Consistent use of diuretics like Dyazide, Maxide or Aldactazide • May reduce Endolymph fluid pressure in the inner ear • Vestibular suppressant medications like Antivert, Benadryl or Transderm Scop • Used to treat acute attacks • Surgical treatment if medical therapy unsuccessful • Vestibular rehabilitation to improve balance

40. Meniere’s Disease • If left untreated: • Severe progressive hearing loss may result • Severe, debilitating vertigo may result

42. The Future • Ongoing research into the Inner Ear and Vestibulocochlear nerve physiology may eventually shed light on the actual mechanisms of hearing loss and vertigo. • Further advances in treatment are currently awaiting research breakthroughs.