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Biomedical subjects

E T Doherty

Publications and source records attributed to E T Doherty.

9 recordsLinked to original sources
PubMed2000

Prevention of pharyngoesophageal spasm after laryngectomy with a half-muscle closure technique.

Because pharyngoesophageal spasm can limit successful voice restoration after total laryngectomy, 24 patients underwent a modified pharyngeal closure in an effort to avoid this problem. All patients underwent total laryngectomy with appropriate neck dissections and pharyngeal closure with a half-muscle closure technique in which only one side of the remnant constrictor muscles was used to reinforce the primary closure. Twenty-three patients underwent voice restoration. Twenty-two (96%) had a functional voice, and 1 patient (4%) had pharyngoesophageal spasm that required a secondary myotomy. One fistula (4%) occurred and resolved with conservative measures. Quantitative voice analysis demonstrated no significant differences between half-closure patients and control patients for fundamental frequency (96 Hz versus 101 Hz) or intensity (57 dB versus 64 dB). Extensive qualitative analysis by trained and naive listeners revealed no differences. This preliminary report indicates the half-muscle closure modification of the pharyngeal closure at primary laryngectomy may provide a simple and effective means of avoiding pharyngoesophageal spasm and maintaining an effective voice without increased complications.

Esophageal Spasm, Diffuse↗
PubMed1999

Effects of sound pressure levels on fundamental frequency in tracheoesophageal speakers.

The quality of tracheoesophageal (TE) voice after laryngectomy is dependent on numerous factors. The relative contribution of specific variables is not well described. To evaluate the modulation of fundamental frequency (F0) pitch in TE speakers after total laryngectomy and voice restoration, we instructed 11 TE speakers to complete a series of vocal tasks under standardized conditions. All patients underwent standard laryngectomy with appropriate neck dissection and full-course radiation therapy. Each speaker produced 4 sustained phonations at distinct levels. Sound pressure level (SPL) intensity and F0 measurements were taken for each level. Statistical analysis to assess the relative effect of SPL on F0 demonstrated a statistically significant effect. However, the knowledge of SPL allowed only a 9% greater prediction of F0, indicating that factors other than SPL are integral to the modulation of F0 by TE speakers. These data lend further support to the theory that TE voice is an active process incorporating the myoelastic properties of the pharyngoesophageal segment as well as the properties of aerodynamic flow.

Biomechanical Phenomena↗
PubMed1998

Quantitative and qualitative analysis of tracheoesophageal voice after pectoralis major flap reconstruction of the neopharynx.

Although tracheoesophageal voice restoration is accepted after reconstruction of the neopharynx with the pectoralis major myocutaneous flap, the character of such voice is not well described. Six patients reconstructed with the pectoralis major flap after laryngopharyngectomy underwent successful voice restoration with the Blom-Singer prosthesis. Voice was evaluated by a standardized protocol and compared with voices of control subjects treated with total laryngectomy and similar voice restoration. The patients with pectoralis major flaps produced similar intensity levels for soft voice (53.7 dB vs. 55.6 dB) and loud voice (61.3 dB vs. 65.3 dB) when compared with controls (p > 0.05). No significant differences (p > 0.05) were noted for fundamental frequency (F0) between patients with pectoralis major flaps and controls for soft (62.3 Hz vs. 85.4 Hz) and loud (109.8 Hz vs. 133.8 Hz) voice. Jitter was also comparable. Trained and naive listeners completed qualitative analyses for 10 parameters and judged that control patients had significantly better voice for most parameters. This finding demonstrates that dependable voice is attainable after pectoralis major flap reconstruction of the neopharynx. Although this voice does not differ significantly from voice after standard laryngectomy for acoustic parameters, perceptual analysis does reveal significant differences.

Carcinoma, Squamous Cell↗
PubMed1994

Tracheoesophageal voice following tubed free radial forearm flap reconstruction of the neopharynx.

Tracheoesophageal voice restoration after laryngectomy is possible with a variety of neopharyngeal reconstructions. We have used the tubed radial forearm free flap for neopharyngeal reconstruction since 1991. Six patients have undergone voice restoration with the Blom-Singer prosthesis and were available for quantitative and qualitative speech analysis. These patients were compared to five laryngectomy patients with standard pharyngeal closures and similar voice restorations. The free flap patients produced similar loudness levels compared to the standards with soft speech (52.06 dB and 47.19 dB, respectively) and loud speech (62.66 dB and 60.91 dB, respectively). The free flap patients demonstrated adequate intelligibility, with fundamental frequencies comparable to standards (124.82 Hz and 135.66 Hz, respectively), although with increased jitter (5.00% versus 1.96%). No differences were statistically significant, but evaluation by trained and naive listeners demonstrated significant differences in voice quality. This quantitative and qualitative and qualitative analysis of tracheoesophageal speech after radial forearm free flap reconstruction of the neopharynx demonstrates that acceptable voice can be achieved, but with limitations.

Aged↗
PubMed1994

Speech measures indicating workload demand.

Heart rate and six speech measures were evaluated using a manual tracking task under different workload demands. Following training, 17 male subjects performed three task trials: a difficult trial, with a $50 incentive for successful performance at a very demanding level; an easy trial, with a $2 incentive for successful performance at a simple level; and a baseline trial, in which there was physiological monitoring but no tracking performance. Subjects counted aloud during the trials. It was found that heart rate, speaking fundamental frequency (pitch), and vocal intensity (loudness) increased significantly with workload demands. Speaking rate showed a marginal increase, while vocal jitter and vocal shimmer did not show reliable changes. A derived speech measure, which statistically combined information from all other speech measures except shimmer, was also evaluated. It increased significantly with workload demands and was surprisingly robust in showing differences for individual subjects. It appears that speech analysis can provide practical workload information.

Adult↗
PubMed1988

Tape recorder effects on jitter and shimmer extraction.

To test for possible contamination of acoustic analyses by record/reproduce systems, five sine waves of fixed frequency and amplitude were sampled directly by a computer and recorded simultaneously on four different tape formats (audio and FM reel-to-reel, audio cassette, and video cassette using pulse code modulation). Recordings were digitized on playback and with the direct samples analyzed for fundamental frequency, amplitude, jitter, and shimmer using a zero crossing interpolation scheme. Distortion introduced by any of the data acquisition systems is negligible when extracting average fundamental frequency or average amplitude. For jitter and shimmer estimation, direct sampling or the use of a video cassette recorder with pulse code modulation are clearly superior. FM recorders, although not quite as accurate, provide a satisfactory alternative to those methods. Audio reel-to-reel recordings are marginally adequate for jitter analysis whereas audio cassette recorders can introduce jitter and shimmer values that are greater than some reported values for normal talkers.

Acoustic Stimulation↗
PubMed1980

Selected acoustic characteristics of pathologic and normal speakers.

The purpose of this study was to determine if measures of speaking fundamental frequency and its perturbation could be useful in differentiating talkers with no known vocal pathology and talkers with cancer of the larynx. Ten male subjects, five with a diagnosed malignancy of the larynx and five with normal voice, produced speech samples from which five voice production measures were obtained: the average speaking fundamental frequency (SFF), SFF variability during the reading of a sentence, the fo of a sustained vowel and a percent and magnitude jitter value. The perturbation factors, both directional and magnitudinal, during sustained vowels were found to be significant in discriminating normal talkers from those with laryngeal cancer. The speaking fundamental frequency and its variability during the reading of a sentence improved the discriminant function.

Aged↗
PubMed1979

Predicting vocal frequency from selected physiologic measures.

Simultaneous physiologic measures were obtained on four young adult male subjects as they sustained phonation at seven frequencies within their modal-to-falsetto voice range. Data were analyzed using a multiple regression program to determine the contribution of each measure singly and in combination with other measures to the prediction of the resultant voice frequency. Results showed that by far the best predictor was cricothyroid muscle activity for both the pooled data model, and for each individual subject. The contribution of subglottal air pressure and thyroarytenoid muscle activity increased the variance explained by only 4% while the measure of vertical laryngeal position was a significant factor in only one subject's predictive model. Partial models from the pooled data explained from 67% to 73% of the variance; whereas the obtained measures for individual subjects explained from 90% to 94% of the variance.

Adult↗