INTRODUCTION
Vocal cord polyps are one of the most common diseases that cause
hoarseness. They are lesions of the larynx that are second only to the
vocal cord nodules. Vocal cord polys are the most common laryngeal
proliferative lesions as well. They are the products of voice overuse,
misuse and abuse. However, vocal cord polys can also be caused from a
traumatic vocal cord injury.1,2 Vocal cord polyps are
typically unilateral benign lesions, most of which are located at the
edge of the anterior 2/3 of vocal folds and can be classified as
pedunculated or sessile.3,4 The vocal folds are made
up of three major layers from superficial to deep: the epithelium or
epithelial tissue, the lamina propria and the vocalis muscle. The most
superficial layer is the epithelial layer of the squamous epithelium.
The middle section is lamina propria which consists of three layers
referred to as superficial, intermediate and deep layers. The
superficial layer of the lamina propria is a jelly-like material made up
pf elastin and interstitial fluid. The intermediate layer is made up of
elastin and the deep layer is mostly collagen, and together they form
the vocal ligament. The thyroarytenoid muscle is the deepest layer of
the vocal folds and is a muscle which is related to activating chest
voice.5
Mechanical vibrations produce strong force during the vocal fold
movement, which may lead to vasodilatation of the submucosa of the vocal
folds, increased permeability of the vascular wall, and
edema.6 The basic lesions occur in the lamina propria
and accompanied by vascular changes. The major features of pathological
characteristics of vocal fold polyps are increased swelling,
inflammation and vascular lesions in the lamina propria
layer.7,8 The histological features of vocal cord
polys are characterized by their appearances (gelatinous or
translucent), fibrous tissue proliferation, and vascular changes
(hemangioma-like changes or hemorrhages). The typical pathological
changes include diffuse or localized edema, fibrosis, dilated blood
vessels, and degeneration of hyaline and basophils in the lamina
propria.6,9 Although some small and hemorrhagic vocal
cord polyps may recover spontaneously or with conservative treatment,
the vast majority of vocal cord polyps require surgical treatment,
especially sessile vocal cord polyps.10,11
Surgical management of vocal cord polyps usually includes
microlaryngoscopic surgery, electronic flexible laryngoscopic surgery,
rigid laryngoscopic surgery, etc.
Microlaryngoscopic surgery is mostly
performed under general anesthesia at hospital. Electronic flexible
laryngoscopic and rigid laryngoscopic surgery can be performed under
local anesthesia in an outpatient setting, which have more advantages in
the simplicity of treatment.12,13Sessile polyps are less effective and
more difficult to treat by surgery than pedunculated polys. Meanwhile,
the
effectiveness of treatment varies depending on the various histological
features of vocal cord polyps. To the best of our knowledge, there is no
report on the evaluation of the effectiveness of surgical performance
for different histopathological types of vocal cord polyps. Based on the
differences of clinical features and histopathological characteristics,
we retrospectively analyzed the clinical efficacy of transnasal
electronic flexible laryngoscopic vocal fold polypectomy and transoral
microlaryngoscopy in the treatment of broad-based sessile vocal cord
polyps.