DIAGNOSIS.--Tracheoscopy, a modification of laryngoscopy, can alone determine with certainty whether, and to what extent, the trachea is inflamed. Unfortunately, very few practitioners have as yet mastered this method of examination, which, though really not more difficult than laryngoscopy, requires greater illumination (necessitating under some circumstances a mirror of longer focal distance) and different relative position of patient and operator. (See article by Seiler.) Figs. 25 and 26 show the tracheoscopical images of a case in which there was intense acute tracheitis. The anterior wall is seen in Fig. 25, and the posterior in Fig. 26; on both, but especially the latter, clumps of phlegm and ramifying injected blood-vessels are distinctly seen. In many cases, by means of the stethoscope, either dry sonorous or mucous râles may be heard over the windpipe; at other times we may be aided in coming to a conclusion by the presence of dysphagia--increased when the chin is raised and diminished when the chin is pressed on the chest, as pointed out by Hyde Salter--and by the morbid sensations, increased by pressure, in the region of the windpipe when there is cough and expectoration. {135} [Illustration: FIG. 25. Acute Tracheitis: anterior wall.] [Illustration: FIG. 26. Same case as Fig. 25: posterior wall.] PROGNOSIS.--Simple tracheitis, though occasionally not without danger in extremely young and very old patients, rarely if ever destroys life. Under good hygienic circumstances it frequently gets well of itself, and it does not usually produce sufficient swelling or hypertrophy to cause stenosis. It is, however, when severe, an annoying disease, apt to recur, and, unless properly managed, difficult to eradicate.