I. Introduction
Secretory otitis media has been noted as the most common cause of the conductive deafness of children and its remarkable increase in recent years is of particular interest.
Although it is well established that the formation of this disease is mainly attributed to the dysfunction of the eustachian tube, additional factors may be involued in some instances. Thus, the complexity of the contributory factors would make the clinical features of the disease more complicated and also make the treatment difficult.
The purpose of this study is to elucidate this disease by clinical evaluations basing on the otological and audiological examinations and by various experimental approaches as described below.
II. Morphological and histopathological studies of the eustachian tube and the middle ear cavity
A. Observations of the normal eustachian tube mucosa and the middle ear mucosa
1. light microscopy
2 scanning electron microscopy
3. transmission electron microscopy
4. histochemistry
5. autoradiography
B. Experimental studies
1. obstruction experiments of the eustachian tubes
2. injection of the antigen into the middle ear cavities
3. injection of the protalgol into the middle ear cavities
C. Observations of human middle ear mucosa in “glue ear”
D. Biochemical analysis of the middle ear fluid
III. Clinical studies of secretory otitis media
A. Statistical analysis
1. the incidence of the disease by years
2. age distribution
B. Signs and symptomes in children
C. Mobility of the ear drum
1. myringo-manometry
2. significance of myringo-manometry
3. simplified method of myringo-manometry and its clinical application
D. Diagnostic values of impedance audiometry
E. Audiograms and their diagnostic values
F. Roentgenologic studies
G. Function of the eustachian tube
1. patency of the tube
2. visualization of the tube on the rentgenogram
H. Other factors affecting the disease
1. tonsils and adenoid tissues
a. measurement of the size of the adenoid tissue on the roentgenograms
b. changes of hearing after adenoidectomy
c. antibody-producing cells in tonsils and adenoid tissues
2. chronic sinusitis
3. skin tests for allergy
I. Cases resistant to the ordinary treatments and so-called “blue ear drum”
IV The evaluation of the ordinary treatments, especially on the transmyringeal insertion of a polyethylene tube
The epithelial cells composing the middle ear mucosa are mainly of non-ciliated type. As the ciliated epithelial cells in the eustachian tube extend further beyond the tubal orf ice into the middle ear mucosa, one can find groups of ciliated cells in the hypotympanum or in the promontry area.
Secretory cells such as goblet cells and of other kinds are dispersed among the ciliated epithelial cells and they form the mucociliary system which is important for the clearance of the middle ear cavity.
Pathological changes of the mucosa in the induced middle ear eff usions are characterized by following features; i, e. sporadic dissociations of the epithelial junctions, formations of wide intercellular spaces which contain the amorphous substance, shrinkage of non-ciliated epithelial cells and increase of the vascular permeability. However, in the human middle ear mucosa in “glue ear”, another feature suggesting the fasciliation of secretory activity of the cells was recognized.
The middle ear effusions of children tend to be looked over due to the difficulty of otological examinations. However, it should be emphasized that the early discovery of the disease is crucial for the prevention of the successive hearing impairment.

View full abstract