Physiology and pathology of the mucociliary system. Special regards to mucociliary transport in malignant lesions of the human larynx

Abstract

After a short historical introduction, the current state of knowledge of the anatomy and physiology of the mucociliary system is reviewed. Description and discussion of the clinical and experimental methods of investigation and measurement of the mucociliary transport and of the ciliary activity then follow. Light and electron microscopy are also considered. Next, the pathology, pathophysiology and pharmacology of the mucociliary system are reported. The introduction ends with the consideration of specific diseases related to the mucociliary system, such as the immotile cilia syndrome. The main interest of this investigation is directed to changes in the ciliary epithelium in laryngeal malignancies. Therefore the literature relevant to physiology is critically evaluated. Pilot studies of the method used for investigating the physiology of the ciliary epithelium were mainly undertaken on the more accessible nasal mucosa as a model for ciliary epithelium. The use of the saccharin test for demonstration of nasal mucociliary transport is thoroughly assessed and the suitability of a new, improved, marking substance was tested. The quantification of cell types for cytological assessment of nasal smears under the phase contrast microscope was appraised. The method of determination of ciliary frequency by microphotometry was evaluated critically by a series of experiments. The author's electron microscopic findings on ciliary epithelium taken from human larynges affected with cancer are also discussed. After these pilot studies the method of the saccharin test and the cytological smear appeared to be unsuitable for oncological investigations. Therefore, mucociliary transport in the subglottic space of 75 human larynges excised for malignancy was investigated by the development of a suitable method. This method demonstrated abnormal mucociliary transport pathways. Investigations of the normal pathway of mucociliary transport in the larynx were obtained in animal experiments and by endoscopic investigations in man.