- Spector JE, Werkhaven JA, Spector NC, et al (Vanderbit Univ Med Ctr, Nashville, Tenn)
Preservation of Function and Histologic Appearance in the Injured Glottis With Topical Mitomycin-C.
Laryngoscope 109: 1125-1129, 1999
This animal experiment in 16 mongrel dogs, where laser injury was induced to the glottis, 8 dogs were treated with 3 minutes application of pledget of cotton soaked with mitomycin-C.
If this further leads to aerosol preparation and is used in human injured larynx due for exposure to toxic chemicals, smoke or fire, intubation, it will be a great boon. Further application if it is not site-specific, it could be used to treat aerodigestive tract.
RW, Titze IR (Univ of Iowa, Iowa City; Denver Ctr for the Performing Arts)
Hyaluronic Acid (with fibronectin) as a Bioimplant for the Vocal Fold Mucosa
Laryngoscope 109: 1142 -1149, 1999.
This study indicates that Hyaluronic acid may be optimal bioimplant for the surgical management of vocal fold mucosal defects because of its biomechanical properties.
Perhaps treatment by hyaluronic acid and mitomycin-C will improve healing and result in improved motion of the vocal mucosa over the muscle.
- Golding GS, Bierbaum RW (Univ of Minnesota, Minneapolis; Medtronic, Inc, Minneapolis, Minn)
Relationship of the Posterior Cricoarytenoid Muscle to the Posterior Cricoid Lamina
Otolaryngol Head Neck Surg 120: 493-498, 1999
This cadaveric study of posterior cricoarytenoid muscle (PCA) identifies two muscle groups on the basis of origin on the PCL and its insertion into the muscular process of arytenoid cartilage. This quantification has implications for electrode design and its placement in those cases where electrical stimulation is used for the paralysed larynx.
- Cho S-H, Kim H-T, Lee I-J, et al (Catholic Univ of Korea, Taejon City)
Influence of Phonation on Basement Membrane Zone Recovery After Phonomicrosurgery – A Canine Model
Ann Otol Rhinol Laryngol 109: 658-666, 2000
Basement membrane zone (BMZ) of the vocal fold is a structure with a unique physiology that plays a key role in phonatory function. There is no data available on the specific histologic healing process of the vocal fold following phonomicrosurgery used to treat polyps, nodules and other benign lesions which do not respond to speech therapy.
Method : Phonomicrosurgery was done in both vocal cords of 20 adult dogs. At 1, 2, 4, 8 and 12 weeks postoperative vocal folds were studied histologically.
Conclusion : The reorganization of the basement membrane is completed by 2 weeks, complete regeneration by 8 weeks. Thus 2 weeks of voice rest appears appropriate and 8 weeks of vocal hygiene to be maintained.
This is an attempt to identify when the basement membrane of the laryngeal mucosa is strong enough to sustain increased distraction forces from vocalization.
In addition to vocal rest, the patient should not cough or clear the throat, as that is likely to be more distracting than gentle speaking.
- Paniello RC (Washington Univ, St Louis)
Laryngeal Reinnervation With the Hypoglossal Nerve: II. Clinical Evaluation and Early Patient Experience
Laryngoscope 110: 739-748, 2000
In laryngeal reinnervation usually the donor nerve is ansa cervicalis. Recent reports of use of XII nerve (hypoglossal) may be an useful alternative.
It was however noticed that (1) hypoglossal nerve in humans might be 2 cm or short to reach the target nerve RLN (recurrent laryngeal nerve).
(2) Having RLN and XII nerve on same side may lead to problems of speech and aspiration. The results of XII-RLN laryngeal reinnervation were assessed in this pilot study.
This was done in 9 patients with evaluation focused on morbidity associated with procedure and results in terms of voice and the swallowing function.
Promising results are reported. The length of the nerve is adequate. The effects of temporary lidocaine block of XII is one good predictor of the effects of surgery. It has thus numerous potential advantages and warrants further study in patients with unilateral vocal fold paralysis (UVFP).
According to G. R. Holt this is an interesting study. Although knowledge of laryngeal innervation phenomena is much greater now than in the past, it is still not known how central and peripheral compensatory mechanisms occur in the presence of neural insults to the larynx – this likely plays some role in recovery after anastomosis.