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Phonomicrosurgery: Strategies
Equipment Plays Key Role
Successful phonomicrosurgery is based on the use of equipment that gives the best unobstructed magnified view of the vocal folds and the use of the most delicate instruments for handling the tissue.
Preservation of Superficial Lamina Propria
Most benign or non-cancerous vocal fold lesions are within the upper sublayers of the vocal fold (epithelia, basement membrane, and superficial lamina propria – the vocal fold mucosa). These upper layers are fairly elastic and vibrate most during voice production. Benign vocal fold lesions seldom extend deeper than the superficial lamina propria, so removal of lesions need not damage deeper structures of the vocal folds. (For more information, see Anatomy & Physiology of Voice Production.)
 Key Information
Removal or destruction of superficial lamina propria causes the epithelium to adhere to the deeper vocal fold structures, restricting vocal fold vibration and making the voice harsh and breathy. (For more information, see Anatomy & Physiology of Voice Production.)
Preservation of Vocal Ligament
The vocal ligament is composed of the intermediate and deep laminae propria, which contain collagen fibers that are stronger and more rigid than the superficial lamina propria contained in the mucosa. The vocal ligament is thought to be responsible for transmitting the action of the vocal fold muscles up to the mucosa, thus allowing vibratory function to occur. Cutting into the vocal ligament can result in a proliferation of cells that produce scar tissue. Scar tissue decreases vocal fold vibration – without proper vocal fold vibration, the voice can be breathy, harsh, or hoarse, which can then result in voice fatigue, voice strain, etc. (For more information, see Anatomy & Physiology of Voice Production.)
Staying in the Proper Surgical Plane
During phonomicrosurgery, it is critical to identify the vocal fold layers, preserve the superficial lamina propria – a layer that is central to vocal fold vibration, and stay in the proper dissection plane. Surgeons often inject saline or other solutions in the plane of the superficial lamina propria to delineate it for optimal preservation.
Minimally Invasive Surgery Principles
As voice research has revealed the importance of the cellular and non-cellular protein substances in the vocal fold, voice surgeons have used smaller and smaller incisions to afford optimal tissue preservation.
Avoiding "Secondary Intention Healing"
It is important to preserve as much of the normal tissue as possible and to cover any exposed deeper layers with epithelium (the lining cover) in order to avoid "secondary intention healing." Secondary intention healing is healing by a process of granulation and scarring, both of which impede or destroy vocal fold vibration.
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