Vocal Fold Microsurgery and Postoperative Rehabilitation – Part 2

Post Operative Posture Memory Rehabilitation using Speech Level Singing Exercises and Balanced Onsets

In 2002 I had the opportunity to publish a study I took part in regarding Vocal Fold Microsurgery for the Journal of Singing magazine.  Here is the second part of that article.  I have added the last part of that post for clarity and consistency, but you can read the first part in it’s entirety here.

Speech Level Singing

The majority of the exercises are used in the Speech Level Singing (SLS).  Developed by Seth Riggs(7), SLS emphasizes a neutral laryngeal position (speech level) as in the position one would find when he or she speaks comfortably.  Riggs’s exercises are designed to create pitch and/or register adjustments using intrinsic laryngeal musculature only.  Adduction is so efficient that very little air is needed to engage the Bernouli effect, therefore ensuring that the folds always close along the whole length.  The exercises are sequenced – in the order presented here – to shape behavior towards the goal of connected singing, without interference of outside muscles, regardless of pitch and/or register.  Audio examples for the ensuing exercises can be found in Riggs’s book, Singing for the Stars.(7)

Lip Trills

In this exercise the lips are put into vibration in addition to the vocal folds.  The purpose is to balance out airflow and resistance to it in order to create favorable subglottal pressure.  Less pressure ensures that extrinsic musculature will not be needed to bring the folds to the midline and help adjust pitch.  To keep the folds and lips vibrating simultaneously, the right balance must be present or the whole process will break down and the folds and/or the lips will cease vibrating.  Titze also notes that, because of the secondary compression created by the lips, supraglottal pressure is created, assisting the closure of the superior portion of the folds as cricothyroid involvement is introduced(8).  This exercise was used in each session.  In addition to the benefits detailed above, it is traditionally recognized as a good warm-up for the instrument and relaxes oral and facial muscles.

The Witch’s Voice

To accustom the subject to the feeling of connected singing throughout the various registers, we actually used the assist of suprahyoid muscles, in this case to lengthen the folds as a pitch rose out of the chest voice and to help promote more complete closure.  The sound of the voice is rather spread and excessively bright and does resemble that of a witch.  Riggs reveals that this exercise dates back to the days of castrati and was used to train the voice on how to bridge out of chest voice through the first passaggio (or bridge, as SLS calls it), into the lower portions of the head voice.  This exercise can not be carried too high, because the involvement of the high larynx muscles puts too much pressure on the larynx as the pitch rises.  As soon as the goal of introducing the subject to a connected sound is accomplished, the exercise should be dropped.

Low Larynx Exercises

According to Bastian, a correlation exists between a lower laryngeal position and more efficient adduction.  We used a bit of a cry or whimper (a “Yogi Bear dumb sound” perhaps is more appropriate) in the voice to promote a lower laryngeal position in this exercise.  This imposition of the “dumb sound” causes the suprahyoid muscles to disengage and the infrahyoid muscles to lower the larynx.

Creaky Voice

Creaky voice is the core exercise of the program in that all adjustments take place in the larynx without the assistance of either high or low larynx muscles.  Creaky voice is a form of phonation that maximizes the lateral cricoarytenoid and interarytenoid groups to adduct the folds in such a manner that very little airflow is needed in order to engage the Bernoulli effect.  This combination of firm adduction coupled with low airflow creates complete medial compression along the full length of the folds regardless of pitch and/or register changes.  According to Riggs(7), all adduction and pitch changes take place intrinsically without the use of suprahyoid or infrahyoid muscle groups.  This form of phonation exhibits a peculiar quality in that it has a squeaky, creaky quality not unlike an unoiled door hinge.  It shares some, but not all, of the qualities of vocal fry and would be in accordance with what Bastian call a stingy use of air(6).

Speech Level Singing also emphasizes a connection out of chest register.  Because the subject of this study is a pop singer, a connection out of chest voice is important to the genre the subject sings and also in achieving full vocal fold closure in the bottom third of the voice.  Lack of thyroarytenoid involvement in the bottom third of the voice leaves the folds too thin; therefore, they do not fill in the gaps and leave too much space between the folds.  The subject is a soprano, and the registration points can be determined from the chart (Figure 1).

Riggs view of registration (heavily influenced by Caesari(10)) is similar to Appleman’s description of the vibrating string theory(11).  As the voice rises out of chest voice (in which the thyroarytenoids are the regulator of pith) the cricothyoid muscles tilt the thyroid and cricoids cartilages toward each other, causing the folds to become longer and thinner.  The amplitude of vibration decreases and the flds vibrate along their whole length.  This is what is described as middle voice (mix) and correlates to Riggs’s first passaggio point (bridge #1).  As pitch continues to rise, the longitudinal tension in the folds increases, but because of a lack of necessary elasticity in the folds, the vibrating margin decreases.  The folds stay closed (adducted) in the posterior portion, and the length of fold left free to vibrate decreases.  Riggs calls this vocal cord shortening(7); others call it dampening (Vennard and Zemling both discuss this phenomenon) (12,13) and it corresponds to Riggs’s description of connected head voice.

Balance Onsets and The Mirror

We also used balanced onsets in the program as a way of fine tuning the prephonatory tuning.  The helped bring about the closed phase our subject was missing, and that is largely missing in singers exhibiting posture memory.

Richard Miller writes about the balanced onset in which prephonatory tuning brings the folds together so that only a narrow slit exists prior to onset of phonation (14).  This even onset is somewhere between a glottal (hard) onset and an aspirated (soft) one.  An immediate, or almost immediate, occurrence of vibrato is also characteristic of a balanced onset.  This exercise was introduced toward the end of the program.  Its therapeutic benefit is questionable with posture memory clients in that it does not necessarily promote building of strength in deficient muscle groups.  However, it promotes proper corrdination after adductor muscles have been strengthened and retrained.  We used one of Miller’s exercises designed to promote coordination in conjunction with the use of a mirror to help the client, via visual feedback, to know if too much air is being wasted.

Conclusion

One can determine from the following photographs (Figures 2-4) that the program proved to be a successful one.  In four sessions, it corrected the posture memory problem and, as shown under stroboscopic examination, created efficient closure between the vocal folds.  The folds behaved so efficiently in the reexamination that Bastian avowed, “If I did not know these folds had surgery on them, I would have never have guessed from this examination.  They look and behave in a completely healthy, efficient manner.”

The principal reason for the observed improvement was the efficacy of exercises and the way they were sequenced in order to shape behavior towards the goal of efficient vocal fold closure using intrinsic musculature.  The fact that the targeted behavior was achieved indicates that the program may also be efficient in other disorders where lack of closure in the vocal folds is the issue.

Although the design of this program was to correct posture memory, the significant change from before treatment to after treatment seems to validate the claim by Speech Level Singing advocates that the training program quickly creates efficient, connected singing through coordinated behavior on a vocal fold level.  However, much more research is needed to fully confirm that finding.

Acknowledgments

My deepest thanks to Dr. Robert Bastian whose input and tutelage were and remain invaluable and greatly appreciated.  Thanks also to Seth Riggs, without whose mentoring and oversight this paper would not have been possible, and to my anonymous subject for her participation.

Notes

  • Cornut and M. Bouchayer, “Phonosurgery for Singers,” Journal of Voice 3 (1989): 269-76.
  • Robert W. Bastian, “Vocal Fold Microsurgery in Singers,” Journal of Voice 4 (1996): 389-404.
  • Robert W. Bastian, “Benign Vocal Fold Mucosal Disorders,” Chapter 111 in Otolaryngology – Head and Neck Surgery, ed. C.W. Cumming and J.M. Frederickson, vol. 3, 3rd (St. Louis: Mosby, 1998), 2096-2129.
  • Robert W. Bastian, “Vocal Fold Surgery in Singers,” Medical Problems of Performing Artists 2 (1987): 49-52.
  • Robert W. Bastian, C. Klitzke, and L. Thurman, “Vocal Fold and Maryngeal Surgery,” Chap 11 in Body, Mind and Voice: Foundations in Voice Education, ed. 1., Thurman and G. Welch, vol. 3, rev. ed. (Iowa City, IA: The Voice Care Network 2000), 620-631.
  • Robert W. Bastian, Clinical observation and conversations at Loyola Medical Center and Loyola Voice Clinic, 1998-1999.
  • Seth Riggs, Singing for the Stars (Van Nuys, CA: Alfred Publishing, 1998(.
  • Ingo Titze, “Voice Research: The Use of Low First Formant Vowels and Nasals to Train the Lighter Mechanism,” Journal of Singing 55, no. 4 (March/April, 1999): 41-42.
  • Seth Riggs, Personal conversations, 1997-1999.
  • Herbert Caesari, The Voice of the Mind (Lndon: Alma Caesare-Gramatke, 1996).
  • Ralph Appleman, The Science of Vocal Pedagogy (Bloomington, IN: Indiana University Press 1967), 64-67.
  • William Vernnard, Singing: the Mechanism and the Technique (New York: Carl Fischer, 1967), 67-69.
  • Willard R. Zemlin, Speech and Hearing Science, Anatomy and Physiology (Englewood Cliffs, NJ: Prentice Hall, 1988), 167-168.