The Center for Laryngeal (Voice) and
Esophageal Disorders
Lee M. Akst, MD, Director
Information for Physicians
General information about voice and swallowing conditions and procedures is available on the Conditions page. Dr. Akst’s treatment philosophies can also be discerned by reading the Treatments and Procedures page, and further information is available in the references found in Dr. Akst’s curriculum vitae. This page is meant to provide more specific and technical information about some of the procedures discussed on the Information for Patients page and is meant to supplement the information available elsewhere on this website.
If you are a physician who would like to discuss a possible referral or patient care with Dr. Akst, please call the office at 708-216-9183. If you would like to reach the appointment line directly, please call 708-216-8563.
Strobovideolaryngoscopy
With normal human speech, vocal fold vibration occurs too rapidly to observe
with a normal camera. At typical frequencies, the male vocal fold oscillates
at 80-120 Hz (cycles/second) and the typical female vocal fold oscillates
at 170-230 Hz. As pitch goes up, the oscillatory frequency of a person’s
vocal cords may reach several hundred cycles/second. Strobovideolaryngoscopy
takes advantage of the periodicity of the waveform of vocal cord vibration
by flashing a strobe light just off the frequency of the vocal cord vibration
itself. By capturing images only when the strobe light is on, and by making
sure that each image is a little farther along in the vocal cord oscillatory
cycle than the image before it, a series of still pictures is assembled
at high speed which gives the impression of constant motion. In this way,
laryngeal videostroboscopy creates a look at vocal cord motion in much the
same way a movie is made by splicing together a series of still images played
at high speed. By slowing down the vocal cord vibratory cycle enough to
observe the “mucosal wave” of the vocal cord, much more information
can be obtained about the mechanics of voice production than might be obtained
without the strobe light. For this reason, strobovideolaryngoscopy is a
crucial tool in analysis of voice disorders.
Phonomicrosurgery
Phonomicrosurgery is laryngeal surgery designed to improve or preserve the
voice. The chief principle of phonomicrosurgery is to save
normal vocal fold superficial lamina propria and epithelium wherever possible.
Voice quality depends upon the pliability of the vocal folds during entrained
vibration, and this pliability comes largely from the superficial lamina
propria – the layer of the vocal cord between the epithelium and the
vocal ligament which is largely gelatinous in consistency. Nodules and cysts
are phonotraumatic lesions which exist deep to the epithelium, within the
superficial lamina propria. If these lesions are resected, the best voice
outcomes will be obtained by meticulous dissection of the lesion with preservation
of as much normal surrounding superficial lamina propria and overlying epithelium
as possible. Several advanced laryngeal surgery techniques
applied to phonomicrosurgery can help to obtain optimal results –
these include the use of laryngoscopes designed to provide
the best possible vocal cord exposure, high-powered operative microscopes,
vocal fold infusion to help delineate the lesion, and the use of subepithelial
resection techniques to save as much normal tissue as possible.
Laryngeal Framework Surgery
Laryngeal framework surgery is designed to improve glottal closure and improve
voice – it is used most often in patients with vocal cord paralysis.
The mainstay of laryngeal framework surgery is medialization laryngoplasty,
in which a transcervical approach is used to create a window in the thyroid
cartilage through which Gore-Tex strips can be placed into the paraglottic
space. The overall effect of medialization laryngoplasty is to permanently
move the musculomembranous vocal fold closer to the midline to allow for
improved glottal closure and stronger voice. In a patient with a paralyzed
vocal cord, medialization laryngoplasty also allows for improved cough and
better airway protection during swallowing. The procedure is done under
local anesthesia with conscious sedation, so that the effect of the implant
on voice quality can be assessed intra-operatively, allowing for “fine-tuning”
of the voice by controlling implant size and shape.
In some patients medialization laryngoplasty alone is not enough to offer a fully satisfactory voice outcome. In particular, those patients with large posterior glottic insufficiency may find that medialization laryngoplasty helps to improve closure within the anterior larynx but allows for continued leak of air posteriorly. In patients that are expected to have difficulty with posterior glottal gaps, adduction arytenopexy is a sophisticated technique that allows for re-positioning of the arytenoid cartilage of the paralyzed vocal cord. Adduction arytenopexy involves actually opening the cricoarytenoid joint, moving the arytenoids cartilage in such a way that it obtains natural phonatory positioning and closes the posterior glottal gap, and then suturing the arytenoids cartilage in this new position. In patients that require the additional posterior glottal closure, adduction arytenopexy is generally performed at the same time as medialization laryngoplasty in order to provide for optimal voice outcomes.
Lastly, cricothyroid subluxation is an innovative procedure that is designed to lengthen a vocal cord which has become flaccid secondary to paralysis and neurologic injury. The technique of cricothyroid subluxation involves placing a suture around the inferior thyroid cornu and the anterior cricoid – tightening this suture then pulls the thyroid forward relative to the cricoid, lengthening a flaccid vocal cord. By simulating the action of the cricothyroid muscle, cricothyroid subluxation allows patients with vocal cord paralysis to enjoy more normal pitch variation than they might otherwise experience.
Those readers interested in more details about medialization laryngoplasty, adduction arytenopexy, and cricothyroid subluxation are encouraged to read the manuscripts written on the topic by Dr. Steven Zeitels.
Pulsed Laser Therapy
Pulsed laser therapy, or pulsed laser photoangiolysis, uses laser energy
to cause angiolysis of vocal cord vasculature without causing thermal damage
to adjacent vocal fold tissue. The ability of the surgeon to do this depends
upon selective absorption by of the laser energy by hemoglobin and the short
pulse width of the laser application. By delivering energy in short pulses
only to the blood vessels, the vessel can be coagulated before the energy
has a chance to diffuse to the adjacent tissue – in this way, the
blood supply to epithelial proliferative diseases such as dysplasia, carcinoma-in-situ,
and recurrent respiratory papilloma (RRP) can be treated while limiting
any damage to the surrounding normal vocal fold. By limiting damage to adjacent
superficial lamina propria, the vocal fold pliability can be maintained
and voice can be preserved. Since conditions such as dysplasia and RRP often
recur, the ability to treat them without causing cumulative vocal cord scarring
is of paramount importance.
The two lasers generally used in this application are the pulsed KTP laser (532 nm) and the pulsed dye laser (585 nm), as these wavelengths fall along peaks of the oxyhemoglobin absorption curve. The principles of photoselective pulsed laser angiolysis were first elucidated by R. Rox Anderson, a dermatologist, in 1984, and the pulsed dye laser was first used to treat cutaneous vascular malformations. After a series of discussions with Dr. Anderson, Dr. Steven Zeitels was the first to use the pulsed dye laser on vocal cords several years ago. In 2005, the pulsed KTP laser was adapted for vocal cord use as well – experience with this laser so far suggests that the KTP laser is more effective and has a wider therapeutic window than the pulsed dye laser, primarily because the pulsed KTP laser has an adjustable pulse-width of 1-30 ms, while the pulsed dye laser is fixed with a very short pulse width of 0.45 ms. Both the pulsed dye and pulsed KTP lasers are fiber-based lasers, which allows for their use both in the operating room through direct suspension microlaryngoscopy and in the office through the sideport of a flexible fiberoptic endoscope.
Laboratory studies presented at the 2006 Annual American Society of Lasers in Medicine and Surgery meeting confirm the lack of adjacent thermal damage seen with the pulsed KTP laser, and several papers have documented its clinical efficacy. If you are interested in learning more about pulsed laser photoangiolysis, please consider the following references:
- Zeitels SM, Akst LM, Burns JA, Hillman RE, Broadhurst MS, Anderson RR. Pulsed Angiolytic Laser Treatment of Ectasias and Varices in Singers. Annals of Otology, Rhinology, and Laryngology 115:571-580, 2006.
- Zeitels SM, Akst LM, Burns JA, Hillman RE, Broadhurst MS, Anderson RR. Office-Based 532nm Pulsed-KTP Laser Treatment of Glottal Papillomatosis and Dysplasia. Annals of Otology, Rhinology, and Laryngology 115:679-685, 2006
- Broadhurst MS, Akst LM, Burns JA, Kobler JB, Heaton JT, Anderson RR,
Zeitels SM. Effects of 532nm Pulsed-KTP Laser Parameters on Vessel Ablation
in the Avian Chorioallantoic Membrane: Implications for Vocal-Fold Mucosa.
Laryngoscope, submitted.
Transnasal Esophagoscopy
Transnasal esophagoscopy (TNE) is an emerging technique in otolaryngology,
and it is proving to be a popular office-based alternative to sedated esophagogasgtroduodenoscopy.
The procedure is well tolerated by most patients with only topical anesthesia
to the nasal cavity and, sometimes, the oropharynx. Transnasal esophagoscopy
allows for high-quality imaging of the nasopharynx, oropharynx, larynx,
and hypopharynx as well as of the esophagus. Because transnasal esophagoscopes
include both suction and instrument sideports, these scopes also serve well
for office-based laser therapy or biopsy. Because of these diverse uses,
transnasal esophogoscopy is gaining an ever-larger role in the diagnosis
and evaluation of head and neck cancer, dysphagia, and odynophagia.
Transnasal esophagosopy is also valuable for esophageal screening among patients with reflux disease. In patients with persistent gastroesophageal reflux disease requiring prolonged PPI use, the role of esophagoscpy in screening for Barrett’s metaplasia and esophageal adenocarcinoma is well-established by the American College of Gastroenterology. For patients with laryngopharyngeal reflux, the indications for esophageal screening are less clear. However, it has been estimated that 7% of patients with laryngopharyngeal reflux will have findings of Barrett’s metaplasia on transnasal esophagoscopy (Koufman JA, Belafsky PC, Bach KK, Daniel E, Postma GN. Prevalence of esophagitis in patients with pH-documented laryngopharyngeal reflux. Laryngoscope 112:1606-9, 2002). Additionally, among patients who ultimately develop esophageal adenocarcinoma, laryngopharyngeal reflux is though to be a more robust predictor of disease than esophageal reflux (Reavis KM, Morris CD, Gopal DV, Hunter JG, Jobe BA. Laryngopharyngeal reflux symptoms better predict the presence of esophageal adenocarcinoma than typical gastroesophageal reflux symptoms. Ann Surg. 239:849-56; discussion 856-8, 2004).
For these reasons, Dr. Akst and other surgeons believe it is reasonable to perform esophageal screening in those patients with laryngopharyngeal reflux that is either refractory to management with PPI’s or which requires long-term PPI use for continued control of symptoms. When transnasal esophagoscopy is performed for esophageal screening of patients with laryngopharyngeal reflux, common findings include esophagitis and hiatal hernia; Barrett’s metaplasia is seen less often. Anecdotally, among patients who have had both office-based transnasal esophagoscy and sedated EGD performed, most patients prefer transnasal esophagoscopy for serial evaluation.
