Changes in the Laryngeal Mucosa After Thyroid Surgery: A Rat Model

Area of Science:

• Otorhinolaryngology
• Surgical Pathology
• Tissue Engineering

Background:

• Thyroidectomy frequently leads to airway symptoms, diminishing patient quality of life.
• Understanding laryngeal mucosa changes post-thyroid surgery is crucial for managing airway complications.

Purpose of the Study:

• To investigate extracellular matrix (ECM) composition shifts in the laryngeal mucosa after thyroidectomy.
• To analyze markers of inflammation and microcirculation in the laryngeal mucosa following thyroid surgery.

Main Methods:

• Sixty Sprague-Dawley rats underwent flap elevation (FE), thyroid and trachea exposure (TE), or thyroid isthmectomy (TI).
• Analysis included TGF-β1, VEGFR-3, CD31, MMP-9 expression, and extracellular matrix (ECM) components (hyaluronic acid, collagen) in the subglottic area (SA).
• Samples were collected on postoperative days 3, 7, and 21.

Main Results:

• Surgical procedures increased subglottic area (SA), hyaluronic acid (HA), and inflammatory markers (TGF-β1, VEGFR-3, CD31, MMP-9) in a manner related to surgical extent.
• Collagen deposition decreased, leading to a higher HA to collagen ratio post-surgery.
• MMP-9 expression was notably higher in the thyroid isthmectomy group.

Conclusions:

• Thyroid surgery, particularly TE and TI, alters subglottic area (SA) and extracellular matrix (ECM) composition, favoring higher hyaluronic acid (HA) and lower collagen.
• Thyroid surgery induces acute inflammation and promotes microcirculation changes and tissue remodeling in the laryngeal mucosa.
• These findings highlight the impact of thyroidectomy on laryngeal tissue homeostasis and potential for airway symptom development.