Dr. Morton Cooper reports outstanding results from using Direct Voice Rehabilitation (DVR) with Bowed Vocal Cords. Covering over 100 cases between 1961 and 2005, his success ratio is excellent (90%+).

Dr. Cooper’s success and cures of this condition were detailed in his textbook Modern Techniques of Vocal Rehabilitation in 1973. From that time on, Dr. Cooper reports faster results because of discoveries he has made with locating the right pitch of voice, the right placement of voice, the better way to breathe right for speaking, and focusing in on the voice image and voice identity, which he finds are all key to successful voice rehabilitation.

The condition of bowed vocal folds as referred to in this book may be functional or organic in etiology. Bowed vocal folds that are functional in nature are created by voice misuse and abuse and may be alleviated by voice rehabilitation. Organic bowed vocal folds have an organic condition or nodules, polyps, or polypoid degeneration in addition to the bowing. Although surgery may be necessary to remove the organic lesions (especially polypoid degeneration) prior to voice rehabilitation, the bowing and the growths are often amenable to voice therapy.

Differentiating Bowed Vocal Folds from Paralytic Dysphonia and Myasthenia Laryngis

Bowed vocal folds may be confused with two other dysphonic conditions which produce a noticeably breathy voice: paralytic dysphonia and myasthenia laryngis.

Myasthenia laryngis is a term used by Jackson to describe “ a morbid entity characterized by asthenia of the phonatory musculature of the larynx, especially the powerful overworked thyroarytenoideus muscles.” (1940, p. 434) Jackson considers myasthenia laryngis as a muscular disability. He posits a continuum of this condition, with the possibility of controlling the early stages through extended voice rest and proper voice training. He adds: “that cure is obtainable only in the earlier stages of the disease.” (p. 461) According to Jackson, myasthenia laryngis is created by too high a pitch in singing and in speaking; voice abuse is the chief etiological factor.

Differential diagnosis between myasthenia laryngis and unilateral paralytic dysphonia in the intermediate (cadaveric) position cannot be made auditorily by the voice therapist. A similar auditory presentation (leakage of air and effortful voice) is afforded to the voice therapist by these two conditions. Unilateral paralytic dysphonia with the cord in the paramedian position may also resemble myasthenia laryngis auditorily, but an effortful volume at the optimal pitch level may reveal a natural voice. Myasthenia laryngis in the final stage does not present a discernible optimal pitch nor a clear tone. The voice quality is noticeably breathy.

The voice therapist may be able to determine if the patient has temporarily bowed vocal folds (functional or organic) or myasthenia laryngis in the final stage. If the patient is able to laugh at his optimal pitch level with a clear tone that is not breathy, the patient has bowed vocal folds. If the sound continues to be breathy when the patient is using the optimal pitch level, then myasthenia laryngis may be present.

In this final stage of myasthenia laryngis, the vocal folds may be bowed, but they respond minimally to maximal voice rehabilitation. The condition of bowed vocal folds (functional or organic) may be considered to be on a continuum leading to myasthenia laryngis (first stage and second stage) if voice misuse is persistent.

Treatment Methods

In some cases of unilateral paralytic dysphonia, the paralyzed cord is bowed in the midline position or in the paramedian position. If the paralyzed fold is in the midline position, voice rehabilitation alone is often successful. If the cord is in the paramedian position and voice rehabilitation alone is unsuccessful, a Teflon injection followed by voice rehabilitation may be necessary (see Paralytic Dysphonia).

When the vocal fold is paralyzed in the midline position or if the patient is in the first stage of myasthenia laryngis, the patient’s production of the optimal pitch level as directed by the voice therapist may immediately result in a clear and normal voice. A program of voice rehabilitation must be undertaken to maintain the optimal pitch.

Clinical Results

Wilson recommends lowering the habitual pitch for bowed cords: “In addition, it is often necessary to eliminate voice abuse such as loud talking and yelling, to establish correct pitch usage often by lowering the habitual level, and to improve the clarity of the voice.” (1966, p. 79)

Clinical experience with 42 patients with bowed vocal folds is entirely contrary to this point of view: almost all of these patients had been using to low a pitch level. Raising the pitch of voice for these patients as well as increasing the oronasal resonance eliminated the bowing and created an efficient voice.

Voice therapy for bowed vocal folds is similar to that used for paralytic dysphonia in which the paralyzed cord is in the median position. (The therapy is described under Paralytic Dysphonia.)

Clinical Results

Of the 32 patients seen with functional bowed vocal cords, the following conclusions may be drawn:

  1. Of the 32 patients seen, 26 (81.25%) entered therapy.
  2. Of the 26 patients entering therapy, 24 (92.3%) completed therapy.
  3. Of the 24 patients completing therapy, 7 (29.2%) had long-term therapy and 17 (70.8%) had short-term therapy.
  4. Of the 24 patients completing therapy, the results were: 20 (83.3%) excellent, 2 (8.3%) good, and 2 (8.3%) fair.
  5. The comparison between males and females seen: 20 (62.5%) males and 12 (37.5%) females.

Of the 10 patients seen with organic bowed vocal cords, the following conclusions may be drawn:

  1. Of the 10 patients seen, 10 (100%) entered therapy.
  2. Of the 10 patients entering therapy, 7 (70%) completed therapy.
  3. Of the 7 patients completing therapy, 3 (42.9%) had long-term therapy and 7 (57.1%) had short-term therapy.
  4. Of the 7 patients completing therapy, the results were: 5 (71.4%) excellent and 2 (28.6%) good.
  5. The comparison between males and females seen: 3 (30%) males and 7 (70%) females.
  6. Of the 10 patients seen, in addition to the bowing: 7 had nodules (5 no surgery, 2 postoperative), 1 had a polyp (1 post-operative), and 2 had polypoid degeneration (1 no surgery, 1 postoperative).


A few testimonials from former Bowed Vocal Cord and Spastic Dysphonia patients: