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New
Treatments for Vocal Problems It was a lovely, late spring evening. The other 100 or so members of my singing group, the Back Bay Chorale, opened their mouths in unison. Out came the exquisite opening chords of the Brahms’ Requiem. I, too, opened my mouth. But nothing came out, or more precisely, nothing beautiful, nothing tunable, nothing remotely resembling what a singer is supposed to sound like. Like millions of other Americans, I had something clearly, and stubbornly, wrong with my vocal cords (also called vocal folds). I had been hoarse for several weeks, following one bout of bronchitis and another of reflux, a condition in which acid from the stomach backs up into the throat, causing inflammation. But geography was on my side. There are only a few American cities blessed with state-of-the-art centers for the diagnosis and treatment of voice disorders, but Boston is one of them. More centers are springing up as the need for them grows. A hundred years ago, most people did not earn their livings with their voices, says Dr. Steven M. Zeitels, director of laryngology at the Massachusetts Eye and Ear Infirmary. But today, in communications-crazed America, the vast majority of workers have jobs that use – and abuse – the delicate vocal cords in the throat, most notably teachers, lawyers, politicians, singers and, the latest crop of victims, telemarketers. In addition to people who wind up with voice disorders because of overuse, many others lose their voices to cancer of the larynx (voice box), throat infections from the papilloma virus, damage to vocal cords during insertion of a breathing tube for surgical operations, paralysis due to nerve damage, and other vocal problems from neurological diseases like Parkinson’s. Fortunately, treatments for voice problems are growing almost as fast as the need. Voice therapy, in which a person learns to take the strain off vocal cords by improving breathing and reducing tension on vocal muscles can work wonders for run-of-the-mill vocal cord damage like mine. For more serious problems, there are new micro-surgical and laser techniques, injections of biomaterials such as collagen or hyaluronic acid to fill in damaged vocal tissues – even a new generation of artificial larynxes for the 5,000 people a year who lose their voices to cancer. The goal is “to reconstitute the structure of vocal folds… so patients can have more normal-sounding voices," says Dr. Charles Ford, chairman of otolaryngology and head and neck surgery at the University of Wisconsin in Madison. The effort to improve treatment of voice problems got a major boost last month (June) from Julie Andrews, whose singing career ended several years ago when an operation to repair her vocal cords ended up damaging them. Andrews is lending her support to a $2 million effort by the Mass Eye and Ear, Massachusetts General Hospital, Harvard Medical School and the Massachusetts Institute of Technology, led by Zeitels. The larynx, a.k.a Adam’s apple, even in women, is one of nature’s least-appreciated marvels. Yet it is "an important part of our humanness," says Dr. Gregory Randolph, director of the general otolaryngology service and thyroid surgical clinic at Mass Eye and Ear. People who lose their voices often feel that loss "takes away their power," he says. At the center of the larynx are the vocal cords – two bands of elastic muscle that lie side by side in the airway, just above the trachea, which itself lies in front of the esophagus (foodpipe) in the neck. When you are silent, the vocal cords remain open, like a valve, so you can breathe. When you start to speak, the vocal cords close. Air is forced upward from the lungs, through the closed cords, forcing them to vibrate – very fast for high pitched sounds, slower for lower pitch sounds. Sound is caused by the release of air through each opening and closing vibratory cycle; it is then shaped in the back of the throat (like the "box" in a guitar) to create resonance - and an individual’s unique voice pattern. The sound is then refined still further, or articulated, by the tongue, teeth and lips to produce all the distinct sounds humans can recognize as speech. But as the vocal cords flap together – women’s vibrate at 180 to 220 cycles per second, men’s at 100 to 140 – they can collide with such force, especially in people who sing, yell or scream loudly and often, that they form nodules at the points of contact. With voice therapy, small nodules, which are like calluses, can recede, though big ones may need surgery. Polyps - small, soft growths that usually occur on only one vocal cord – are also caused by micro-trauma to the vocal cords. But one of the leading causes of laryngitis (swelling of vocal cords) is reflux of stomach acid up into the back of the throat. As I discovered, you can have reflux and not know it until you lose your voice. "Many people assume that if they don’t have heartburn, they don’t have reflux. That’s not true, “ says Zeitels. Reflux – often characterized by frequent throat-clearing - can be triggered by caffeine, alcohol and carbonated beverages; it can be treated effectively with acid-reducing medications. (Laryngitis can also be caused by respiratory infections, allergies, smoking, chemical fumes and overuse; smoking can also cause vocal cord tumors.) One way to repair damaged vocal cords is “tissue engineering" to create better biomaterials. At MIT, Robert Langer, professor of chemical and biomedical engineering, and his team are studying materials such as hyaluronic acid, collagen or elastin that could be injected or implanted into damaged vocal cords to plump up and restore pliability to damaged sections of cords. "We need a material that can vibrate, that has the right elasticity, that is safe and that can withstand the frequency" at which vocal cords collide, Langer says. Another alternative is to create such a material from scratch. In a recent issue of the journal Nature Biotechnology, Langer’s team reported that it had made a new kind of "biorubber" that is “very elastic and very biocompatible," he says. Still another way to restore vocal cord tissue is to use stem cells taken from a donor or vocal cord cells taken from the patient himself. In either case, the idea is to start with a small sample of these cells, chemically stimulate them to grow in the lab and, when there is enough viable tissue, inject or implanted it onto the damaged areas of the vocal cords. Increasingly sophisticated surgical approaches are also underway. At Mass Eye and Ear, surgeons can often restore vocal function in patients with one paralyzed vocal cord, which can occur when nerves to the larynx are damaged by pressure from tumors, from inflammation or in rare cases, from being cut inadvertently during neck or thyroid surgery. When a vocal cord is paralyzed, it can’t move in and out with the other cord, kind of like trying to clap with only one movable hand. But now, in a procedure pioneered by Zeitels, surgeons can move the paralyzed cord a few millimeters closer to the healthy one so the cords can close together to produce speech. Jeremy Geidt, 72, a senior actor at the American Repertory Theatre in Cambridge, is a happy beneficiary of just that approach. During chest surgery last fall at another hospital, Geidt’s right vocal cord was paralyzed. But Zeitels operated recently and a delighted Geidt got his voice back: “He did the brilliant handiwork. He is super.” Lasers, too, are finding a role in vocal cord repair. Dr. Rox Anderson, a laser surgery specialist at MGH, is working with Zeitels to use pulsed dye lasers to heal vocal cord damage from scarring or papilloma virus infections. The laser selectively destroys tiny blood vessels and causes scars to soften, says Anderson. For many patients, the laser treatment can be used under local anesthesia. There is even growing hope for people who have had their larynxes removed because of cancer. Until recently, artificial larynx technology had been largely unchanged since World War II, says Robert Hillman, director of the voice and speech lab at Mass Eye and Ear. He holds one such device, a small cylinder, to his neck, pushes a button and mouths, "One, two, three." The device, called an electrolarynx or "shaker", literally creates buzz in the throat that is shaped into identifiable speech by the throat, mouth, lips and tongue and teeth even though no air is passing through the vocal cords. The words that come out sound highly robotic – but understandable. The goal now, says Hillman, is to create a better voice simulator such as the one his graduate student, Ehab Goldstein is working on. In this system, still highly experimental, a nerve near the voice box is surgically re-routed to a different muscle in the neck. The contraction of this muscle can then be picked up on the surface of the skin and used as a signal to power a voice-synthesizer. So far, though the surgery has been done in 13 people, all are still waiting for further development of the technology. Just as treatments are getting better, so is the ability to pinpoint what’s wrong in the first place. "Diagnostically, the big advance is the voice lab," says Dr.Gary Bellack, clinical chief of otolaryngology at Cedars-Sinai Medical Center in Los Angeles. As I can attest. At Mass Eye and Ear, I willingly submitted to mild, friendly torture as a stream of people poked tubes down through my nose and throat to get a close look at my vocal cords. (Not fun, but not as bad as I expected.) One of these exams used a strobe light and camera attached to the end of a long tube to make moving pictures of my cords flapping like the wings of some poor, distressed hummingbird as I croaked an awful "eeeee." The moving image on the computer screen could then be stopped to catch the nodules on my vocal cords in mid-collision. Then, Patricia Doyle, a singer herself as well as senior speech pathologist at Mass Eye and Ear, set to work. She made me sing a few notes. (Dreadful.) She had me read standardized texts into a microphone attached to a digital recorder to gauge my normal pitch and volume. Then she had me sing more eeeee’s and aaaaa’s, also recorded, to determine exactly how hoarse I was. I read yet another standard passage as she counted the number of times I made harsh glottal attacks. (Too many: another sign that my vocal cords were banging together too abruptly, and getting damaged in the process.) With a special mask covering my nose and mouth to catch all my expelled air, she had me say "Pah, pah, pah" over and over as a computer kept track of how much air pressure I needed to get my vocal cords vibrating and to measure the amount and speed of the air flowing between my vocal cords. Then came the hard, that is, my part. Once a week, I went in for therapy – learning how to control my breathing, get better resonance from my throat and mouth and relax all the muscles needed to vocalize without strain. It’s working, and I’m delighted: Singing season starts again in the fall.
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