Pathology and clinical features


The diseases runs through the following stages:

1. Stage of tubal occlusion
2. Stage of pre-suppuration
3. Stage of suppuration
4. Stage of resolution or complication

1. Stage of tubal occlusion.

Oedema and hyperaemia of nasopharyngeal end of eustachian tube, blocks the tube, leading to absorption of air and negative intratympanic pressure. There is retraction of tympanic membrane with some degree of effusion in the middle ear but fluid may not be clinically appreciable.
Symptoms.
Deafness and earache are the two symptoms but they are not marked. There is generally no fever.


Signs.

Tympanic membrane is retracted with handle of malleus assuming a more horizontal position, prominence of lateral process of malleus and loss of light reflex. Tuning fork tests show conductive Deafness.

2. Stage of pre-suppuration.

If tubal occlusion is prolonged,
pyogenic organisms invade tympanic cavity causing hyperaemia of its lining. Inflammatory exudate appears in the middle ear. Tympanic membrane becomes congested.

Symptoms.

There is marked earache which may disturb sleep and is of throbbing nature. Deafness and tinnitus are also present, but complained only by adults. Usually, child runs high degree of fever and is restless.

Signs

. To begin with, there is congestion of pars tensa. Leash of blood vessels appear along the handle of malleus and at the periphery of tympanic membrane imparting it a cart-wheel appearance. Later, whole of tympanic membrane including pars flaccida becomes, uniformly red.Tuning fork tests will again show conductive type of hearing loss.

3. Stage of suppuration.

This is marked by formation of pusin the middle ear and to some extent in mastoid air cells. Tympanicmembrane starts bulging to the point of rupture.

Symptoms.

Earache becomes excruciating. Deafness increases. child may run fever of 102-103"F. This may be accompanied by vomiting and even convulsions.

Signs

. Tympanic membrane appears red and bulging with loss of landmarks. Handle of malleus may be engulfed by the swollen and protruding tympanic membrane and may not be discernible. A yellow spot may be seen on the tympanic membrane where rupture is imminent. In pre-antibiotic era, one could see a nipple-like protrusion of tympanic membrane with a yellow spot on its summit. Tenderness may be elicited over the mastoid antrum.

X-rays of mastoid will show clouding of air cells because of
exudate.

4. Stage of resolution.

The tympanic membrane ruptures withrelease of pus and subsidence of symptoms. Inflammatory processbegins to resolve. If proper treatment is started early or if the infectionwas mild, resolution may start even without rupture of tympanicmembrane.
Symptoms.

With evacuation of pus, earache is relieved, fever comes down and child feels better.
Signs.

External auditory canal may contain blood tinged discharge which later becomes mucopurulent. Usually, a small perforation is seen in antero-inferior quadrant of pars tensa.Hyperaemia of tympanic membrane begins to subside with return to normal colour and landmarks.

5. Stage of complication.

If virulence of organism is high orresistance of patient poor, resolution may not take place and diseasespreads beyond the confines of middle ear. It may lead to acutemastoiditis, subperiosteal abscess, facial paralysis, labyrinthitis,petrositis, extradural abscess, meningitis, brain abscess or lateralsinus thrombophlebitis.


Treatment