Time-Synchronized MRI-Assessment of Respiratory Apparatus Subsystems-A Feasibility Study.

The thorax (TH), the thoracic diaphragm (TD), and the abdominal wall (AW) are three sub-systems of the respiratory apparatus whose displacement motion has been well studied with the use of magnetic resonance imaging (MRI). Another sub-system, which has however received less research attention with respect to breathing, is the pelvic floor (PF). In particular, there is no study that has investigated the displacement of all four sub-systems simultaneously. Addressing this issue, it was the purpose of this feasibility study to establish a data acquisition paradigm for time-synchronous quantitative analysis of dynamic MRI data from these four major contributors to respiration and phonation (TH, TD, AW, and PF). Three healthy females were asked to breathe in and out forcefully while being recorded in a 1.5-Tesla whole body MR-scanner. Spanning a sequence of 15.12 seconds, 40 MRI data frames were acquired. Each data frame contained two slices, simultaneously documenting the mid-sagittal (TH, TD, PF) and transversal (AW) planes. The displacement motion of the four anatomical structures of interest was documented using kymographic analysis, resulting in time-varying calibrated structure displacement data. After computing the fundamental frequency of the cyclical breathing motion, the phase offsets of the TH, PF, and AW with respect to the TD were computed. Data analysis revealed three fundamentally different displacement patterns. Total structure displacement was in the range of 0.94 cm (TH) to 4.27 cm (TD). Phase delays of up to 90∘ (i.e., a quarter of a breathing cycle) between different structures were found. Motion offsets in the range of -28.30∘ to 14.90∘ were computed for the PF with respect to the TD. The diversity of results in only three investigated participants suggests a variety of possible breathing strategies, warranting further research.

Objective measurement of vocal fatigue in classical singers: a vocal dosimetry pilot study.

OBJECTIVES: To collect objective vibration dose data on singers and relate them to subjective measurements of vocal fatigue. STUDY DESIGN AND SETTING: Seven subjects completed a 2-week study period. The National Center for Voice and Speech (NCVS) dosimeter recorded vocal load, soft phonation tasks, and subjective soft voice ratings. Three vocal doses (time, distance, and cycle) were measured in classical singers' larynges during an intensive practice period. RESULTS: Spikes in vocal load are reflected as harsher subjective ratings on the same day as well as 24-72 hours later. When at least 48 hours of vocal rest occurred before a vocal load, improved subjective evaluations were seen after the load. CONCLUSIONS: The NCVS dosimeter appears to be an effective tool for data collection on prolonged use of the voice. SIGNIFICANCE: This is the first multi-day study comparing objective and subjective data on vocal fatigue in a group of professional singers.

Vocal range and intensity in actors: a studio versus stage comparison.

A voice range profile (VRP) was obtained from each of eight professional actors and compared with two speech range profiles (SRPs). One speech profile was obtained during the dramatic reading of a scene in the laboratory and the other during a performance on stage in a professional theater. The objective was to determine the pitch and loudness ranges used by the actors in speech relative to the VRP. The principal question of interest was whether the actors stayed within the center of the VRP, or whether they tended to drift toward the boundaries of intensity and frequency. A second question was whether the performance within the laboratory accurately reflects that of a stage performance. The results suggest that some subjects tend to exceed the center of the VRP during the stage performance. It is hypothesized that these actors may stress their vocal mechanism during performance and are more likely candidates for vocal injury.

Nontraditional tools helpful in the treatment of certain types of voice disturbances.

Voice therapy has evolved considerably over the past decade. Our field has learned to draw from other disciplines to help facilitate the restoration of vocal function by implementing a more holistic approach and utilizing principles of motor learning to create our therapy programs. Clinicians have learned to recognize that the voice is more than just the larynx. Rather, it is a whole body system, and breakdowns in systems throughout the body can be responsible for vocal disturbances. This review will cover the nontraditional approaches that aid in treating certain voice disorders that often are not discussed in textbooks or classrooms. Facilitating techniques include principles from singing and acting voice production, Feldenkrais, Alexander technique, Qigong, and circumlaryngeal massage.