Abstract
In order to decide the feasibility of conservation surgery in hypopharyngeal carcinoma, an accurate preoperative determination of involvement into various laryngeal structures is necessary. Twenty-two cases of hypopharyngeal carcinoma were investigated to evaluate the preoperative diagnostic accuracy of determination of the extent of laryngeal involvement by comparing preoperative CT and inspection with corresponding histopathological findings of whole organ serial section study after total laryngopharyngectomy. The results were summerized as follows: 1) Estimation of the involvement into laryngeal cartilages by CT was difficult. Most incorrect readings were false positives due to overestimation. 2) Invasions into thyroarytenoid, cricothyroid, lateral cricoarytenoid and interarytenoid muscles were detected relatively easily, but those of the posterior cricoarytenoid muscle were difficult to determin by CT. For the estimation of the involvement into the interarytenoid and posterior cricoarytenoid muscles, inspection proved more useful than CT. 3) Invasion into the paraglottic space was easily detectable by CT, but at the glottic level, it was difficult to detect by inspection. In the preepiglottic space, some false positive cases were observed with CT, but it was almost possible to determine the invasion by inspection. 4) In the aryepiglottic fold, there were some false positive diagnoses with CT. Inspection was more accurate than CT. 5) It was possible to predict the invasion into the recurrent laryngeal nerve by CT.
