Structures Constituting the Sound Source After the Treatment of Early Glottic Cancer

Summary 

Introduction

We indicate the exclusive radiation therapy as initial approach for T1a glottic tumors, and the frontolateral laryngectomy for the tumors staged as T1b and selected T2 glottic tumors. The videolaryngostroboscopy is a useful tool to analyze the laryngeal structural changes and compensatory motion after the therapeutic approach.

Objectives

To evaluate the endolaryngeal structures of patients who participate in the vibratory sound source after the early glottic cancer treatment through the videolaryngostroboscopy.

Methods

It was a retrospective transversal study in which 20 patients who underwent exclusive radiation therapy and 25 patients who underwent frontolateral laryngectomy were analyzed by means of videolaryngostroboscopy. The radiation doses ranged from 5000 to 7020cGy in the radiation therapy group. The mucosal wave and the vibratory source components were evaluated.

Results

All of the irradiated patients presented vibratory behavior, and hyperfunction was occasionally observed in four cases. The mucosal wave source was glottic in 18 cases and mixed in two cases. In the laryngectomy group, 10 supraglottic sources, 10 glottic sources, and five mixed sources were identified. Among the 10 cases of supraglottic source, eight patients presented global constriction and two patients presented medial constriction. Among the five cases of mixed source, two patients presented global constriction, one patient presented medial constriction, and one patient presented anteroposterior constriction. Regarding the number of anatomical structures presenting vibratory pattern, five patients had two structures, four patients had three structures, and one patient had four structures.

Conclusion

Patients who underwent radiation therapy recruit less supraglottic structures as vibratory source than the patients undergoing vertical laryngectomy.

Key Words: Laryngeal neoplasms, Laryngoscopy, Laryngectomy, Radiotherapy