Archive for ENT Tit-Bits

Mechanism of Sound Production in Humans

Humans produce speech and singing sounds using Myoelastic-Aerodynamic mechanism (MEAD).

Vocal folds oscillate from about 100 times/sec in normal speech to 1400 times/sec during highest possible notes.

Ethmoidal arteries

Ethmoidal arteries may be absent.

  1. Anterior Ethmoidal A. ~7-14%
  2. Posterior Ethmoidal A. ~31%

Rhinitis Medicamentosa

Topical nasal decongestants work because of alpha agonistic action.

Rebound nasal congestion occurs due to mild beta agonist action of the agents. Over a period of time alpha receptors also become refractory to the agents.

Nonallergic Rhinitis

Mostly does not have inflammatory reaction (Exception is Nonallergic Rhinitis With Eosinophilia).
Develops in adulthood.

Samter’s Triad

  1. Rhinitis /Sinusitis Nasal polyps
  2. Asthma
  3. Aspirin Sensitivity

Other Names

  • AERD (aspirin-exacerbated respiratory disease)
  • AIAR (aspirin-induced asthma and rhinitis)
  • Widal’s triad (or syndrome)
  • Widal-Abrami-Lermoyez triad
  • Widal-Lermoyez triad
  • Francis’ triad
  • Aspirin triad
  • Aspirin intolerance
  • Aspirin-sensitive asthma

Nasal Valves

  • Internal Nasal Valve
  1. Upper Lateral Cartilage
  2. Cartilaginous Septum
  • External Nasal Valve
  1. Fibrofatty Alar Tissue
  2. Caudal Septum
  3. Lower Lateral Cartilage
  4. Piriform Aperture

Auditory Dyssynchrony

Also synonymous with Auditory Neuropathy.

  1. Disordered Speech and language processing OUT OF PROPORTION to hearing loss.
  2. Normal Cochlear Function on OAE.
  3. Abnormal or severely deranged ABER.
  4. Stapedial reflex absent or increased threshold.

Sensorineural Hearing Loss in Children

Most Common Infectious Cause

  1. Congenital CMV.
  2. Postnatal Bacterial Meningitis.

Most Common Anatomical Cause

  • Enlarged Vestibular Aqueduct

Most Common Genetic Cause

  • Mutation in Gap Junction Beta 2 Gene

Signs of imbalance in very young children.

Very young children cannot express or articulate their symptoms properly hence following signs need to be noted or asked about to the guardians:

  1. Episodic ?
  2. Imbalance
  3. Staggered or clumsy Walk
  4. Repeated falls on standind or walking.

Tinnitus : current theory

Compensatory Hyperactivity :

Decreased activity / stimulus in the auditory nerve upregulates the central nuclear activity in ascending auditory pathways.