الفهرس 
ANATOMY AND HISTOLOGY OF THE VOCAL FOLDSOnly 14 pages are availabe for public view
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Abstract
Phonosurgery is laryngeal surgery done solely or primarily to improve phonation which requires some glottis adjustment by altering the physical characteristics, placement, contour and function of the vocal folds. Therefore, when closure is improved often gains are achieved not only in voice but also in breathing and swallowing. It is based on the intended operative aim and not on the surgical method.
To establish a practical classification system for PS, we propose four groups of operations:-
1. Vocal fold surgery (VFS): surgical procedures performed directly on the vocal folds either by:
Cold instrument (conventional microlaryngeal phonosurgery).
Laser assisted (Laser microlaryngeal phonosurgery).
2. Laryngeal framework surgery (LFS): Surgical procedures performed on the laryngeal skeleton and/or inserting muscles for correction of position and/or tension of the vocal folds.
3. Neuromuscular surgery (NMS): Surgical procedures performed on the laryngeal neuromuscular structures for restoring mobility and/or tension of the vocal folds.
4. Reconstructive surgery (RCS): Surgical procedures for restoring the voice after loss of functional structures or the entire larynx.
Modern and functionally oriented phonosurgery is based on: progress in functional microanatomy, including Hirano’s body-cover theory, Gray’s work on cellular physiology, studies on benign lesions, knowledge acquired in perceptual evaluation and laboratory assessment of dysphonia and progress in the operating microscopes, laryngoscopes and new phonosurgical instruments as well as CO2 lasers.
The vocal fold is a multilayered vibrator structure which gives the vocal folds their mechanical properties. These structures oscillate during the production of sound. According to cover-body complex theory layers structure can be classified into 3 sections:-
4- Cover: epithetlium + superficial layer of lamina propria.
5- Transition portion: intermediate and deep layers of lamina propria.
6- Body(core): vocalis muscle.
Benign superficial lesions of the vocal folds arise from the epithelium and the superficial layer of the lamina propria. Vocal abuse and misuse presumably lead to excessive mechanical stress and trauma in the membranous portion of the vocal fold resulting in wound formation. Wound healing leads to remodeling of the superficial layer of the lamina propria. This tissue remodeling leads to formation of benign vocal fold lesions.They include:
- Vocal fold polyp.
- Vocal fold cyst.
- Vocal fold nodules.
- Reinke’s oedema and polypoid degeneration.
- Vocal process granuloma.
These lesions are classically treated either by conventional microsurgery or recently by CO2 laser. The use of the CO2 laser for surgical treatment of Minor Associated Pathological Lesions (MAPL’s) is still controversial. Some preferred cold instruments, whereas others appreciate CO2 laser as a novel alternative to conventional microsurgery for benign vocal fold lesions. To summarize the reviewed literature the issue of CO2 laser versus cold instruments is still controversial and the stage is open for more studies.
The general principles for microlaryngeal phonosurgery:
- Good visualization.
- Preservation of normal tissue.
- Avoidance of injury to the intermediate and deep layers of the lamina propria.
Surgical procedures are performed directly on the vocal folds with the aim of:
1- Improving the vibratory movement restoration of the normal mucosal wave.
2- Correction of vocal folds position and/or tension.
The objective is to create a common language in order to improve the surgical description of the procedures proposed by different authors for addressing specific vocal fold lesions or disorders. This common language will simplify postoperative outcome comparisons, standardize phonosurgical procedures and facilitate the teaching of phonosurgery.