NPPCD

Deafness.

Anatomy of the Ear

The ear is divided into three main parts:

1. External Ear

• Pinna (Auricle): Captures sound waves and directs them into the ear canal.
• External Auditory Canal: Carries sound to the tympanic membrane.

2. Middle Ear

• Tympanic Membrane (Eardrum): Vibrates in response to sound waves.
• Ossicles (Tiny Bones):
• Malleus (hammer)
• Incus (anvil)
• Stapes (stirrup)
  These bones amplify and transmit vibrations from the eardrum to the inner ear.
• Eustachian Tube: Equalizes pressure between the middle ear and atmosphere.

3. Inner Ear

• Cochlea: Spiral-shaped organ responsible for converting sound vibrations into nerve impulses.
• Vestibular Apparatus (Semicircular Canals, Utricle, Saccule): Helps maintain balance.
• Auditory Nerve (Cochlear Nerve): Transmits signals from the cochlea to the brain.

Physiology of Hearing

1.     Sound waves enter the external ear.

2.     Tympanic membrane vibrates, moving the ossicles.

3.     Stapes taps on the oval window, creating fluid waves in the cochlea.

4.     Hair cells in the cochlea detect fluid movement and convert it into electrical signals.

5.     Auditory nerve carries these signals to the brain, where sound is interpreted.

Etiopathogenesis and Pharmacotherapy of Deafness – Summary

Etiopathogenesis of Deafness

Deafness is caused by damage or dysfunction in the auditory pathway and is broadly classified into:

1. Conductive Hearing Loss

Occurs due to obstruction or damage in the external or middle ear, preventing sound conduction.

• Causes:
• Impacted ear wax
• Otitis media (acute, chronic, secretory)
• Tympanic membrane perforation
• Otosclerosis
• Trauma or foreign body

2. Sensorineural Hearing Loss (SNHL)

Caused by damage to the cochlea, auditory nerve, or central auditory pathways.

• Causes:
• Congenital (genetic syndromes, birth injuries)
• Presbycusis (age-related)
• Noise-induced hearing loss
• Ototoxic drugs (e.g., aminoglycosides, cisplatin)
• Infections (e.g., rubella, meningitis)
• Head trauma

3. Mixed Hearing Loss

Involves both conductive and sensorineural components.

Pharmacotherapy of Deafness

Treatment depends on the underlying cause and type of deafness.

1. Conductive Hearing Loss

• Ear wax:
• Wax softeners: Carbamide peroxide, hydrogen peroxide, sodium bicarbonate drops
• Infections:
• Acute Otitis Media: Amoxicillin or amoxicillin-clavulanate
• Chronic Otitis Media: Topical antibiotics (e.g., ciprofloxacin drops)
• Otitis externa: Antibacterial or antifungal ear drops
• Inflammation:
• Steroid drops for allergic or inflammatory conditions

2. Sensorineural Hearing Loss

• Sudden SNHL:
• Systemic or intratympanic corticosteroids (e.g., prednisolone)
• Autoimmune causes:
• Immunosuppressive therapy (steroids, methotrexate)
• Infectious causes (e.g., syphilis):
• Specific antibiotics (e.g., penicillin)
• Ototoxicity:
• Discontinuation of offending drug
• Antioxidants under research (e.g., N-acetylcysteine)

3. Supportive Therapy

• Hearing Aids for irreversible hearing loss
• Cochlear Implants in profound SNHL
• Speech and language therapy
• Tinnitus management (e.g., ginkgo biloba, anti-anxiety meds)

National Programme for Prevention and Control of Deafness (NPPCD)
Objectives, Functioning, and Outcomes – Summary

Objectives:

1. Prevent avoidable hearing loss due to disease or injury.
2. Ensure early identification, diagnosis, and treatment of ear problems.
3. Provide medical rehabilitation for people of all age groups with hearing loss.
4. Strengthen inter-sectoral linkages for long-term rehabilitation.
5. Develop institutional capacity through training and equipment.
6. Reduce the overall burden of hearing impairment by 25% by the end of the 12th Five Year Plan.

Functioning:

• Training & Capacity Building:
  Training of ENT specialists to grassroot workers (e.g., ASHAs, AWWs, teachers). Strengthening PHCs, CHCs, and district hospitals with ENT kits and diagnostic tools.

• Service Provision:
  Audiometric assistants and speech instructors posted at district hospitals. Services include screening, treatment (medical/surgical), rehabilitation, and referral.

• Awareness Generation (IEC/BCC):
  Public campaigns to promote early detection and reduce stigma around deafness.

• Screening Camps & School Screening:
  Regular camps and annual screening of primary school children for ear conditions.

• Hearing Aids Distribution:
  Free hearing aids provided to children under 15, with one-year service support.

Outcomes:

• Expansion to 228 districts across 27 States/UTs.
• Over 6,380 hearing aids distributed.
• More than 335 screening camps conducted.
• Improved public awareness, early intervention, and infrastructure for ear and hearing care.