Abstract
Clinical and histopathological investigations were performed on 175 cases of the laryngeal polyp in order to elucidate its etiology and development. Six larynges with the laryngeal polyp were examined out of 922 cases obtained by autopsy.
The results were as follows:
1) The laryngeal polyps are classified into three types according to their features; i. e., vocal cord polyp, vocal nodule and polypoid degeneration of the vocal cord. However, no histolgical differences were found among them.
2) The hoarseness was found in the history of many cases to occur suddenly in course of common cold or after the excessive use of the voice.
3) The polyp was most freqwmtly observed at the middle portion of the membranous vocal cord where the vibration of the vocal cord is the strongest (60.5%).
4) The vocal cord polyp was clinically classified into red and white one, the ratio of which was 3 to 1.
5) The polyp was histologically classified into 4 types; 1) fibrous, 2) oedematous, 3) hemorrhagic, 4) hyalinization. The most noticeable findings were the vascular i:changes such as vascular dilatation, hemorrhage, thrombus and hyalinization. Hemorrhage (fresh and old) was observed in 64% of all cases and hyalinization in 82%. Both of them were frequently found in the same specimen, especially in the early cases. It was suspected that the hyalinization was a degenerative change of hemorrhage. The fibrous type was mostly noticed in large and longstanding polyps. It indicates that the fibrous change of the tissue of the polyp is the final stage of histology.
6) Six larynges obtained by the autopsy were used to the examination by the large section, which revealed that all of the polyp originated at the site of stratified squamous cells epithelium of the vocal cord and the histological change was not limited only in the polyp but found in the surrounding tissue of the polyp.
From the results described above and the consideration of the physiology of the vocal cord as a “high speed vibrator”, the etiology of the laryngeal polyp was concluded to be circumscribed hemorrhage in the subepithelial layer of the vocal cord.
