Velopharyngeal Gap Research Articles

The use and limitations of the barium pharyngogram in the detection of velopharyngeal insufficiency.

A barium pharyngogram was incorporated into the multiview videofluoroscopic evaluation of the velopharyngeal portal in 195 subjects in order to assess its usefulness in demonstrating competence or incompetence. Reflux of barium was always associated with a velopharyngeal gap and/or hypernasality; however, the absence of reflux was not similarly diagnostic. The pharyngogram proved to be useful in confirming the presence of a palatal or pharyngeal-flap fistula. While it is helpful in assessing velopharyngeal closure in selected cases, it should not be used in the absence of other information.

Velopharyngeal relationships of /i/ and /s/ as seen cephalometrically for persons with suspected incompetence.

Measurements of velopharyngeal gaps were obtained for 110 subjects with suspected velopharyngeal incompetence. Cephalometric x rays during a high vowel, /i/, and a sustained voiceless sibilant, /s/, were compared. Velopharyngeal gaps for the two phonemes differed in group means and for most individual subjects, with greater gaps being found for /i/ than for /s/. Persons with smaller gaps generally were found to have /i/ gaps in the absence of /s/ gaps, and greater /i-s/ discrepancy. Relationships between velum and pharyngeal wall perceived cephalometrically during /i/ and /s/ were not found to be equivalent. Generally, the /i/ radiograph agreed better with presumed velopharyngeal incompetence.

The effect of muscle exercise on velopharyngeal gap and nasality

The effect of muscle exercise on velopharyngeal gap and nasality

The modification of velar movement.

The use of displacement transducers and certain procedures for training in an initial attempt to increase soft palate movement in a person with velopharyngeal inadequacy is described. An intraoral appliance with associated instrumentation for monitoring velar movement during speech is also described. Systematic training procedures using the visual feedback of velar movement offered by the transducer appliance were carried out over a period of approximately three months. Baseline elevation and elevation under visual feedback only were determined initially. Conditioning sessions followed during which the subject received points or reinforcement each time he achieved a predetermined criterion of velar elevation. Radiographs were taken before and after the study. Velar elevation was modified, but other structural changes negated any changes in velopharyngeal gap or the perceptual characteristics of speech. Problems encountered in instrumentation and procedure are reported.

Quantitative Comparison of Perception of Nasality and Cinefluorographic Analysis of the Velopharyngeal Mechanism

There is a continuing question in clinical literature about what is meant by the term “nasal speech” and about the measurement of this phenomena. Bzoch (1971) and others (Moll, 1968, and Kantner, 1964) insist upon an operational definition, which includes a listener's general perception of acoustic features of the voice quality. Bzoch also states that velopharyngeal insufficiency alone may not be a determinant of hypernasality. This study investigates the relationship of degree of velopharyngeal gap, as determined by cinefluorographic, to listener judgements of hyper- and hyponasality. Two judges rated 30 subjects with a known degree of velopharyngeal gap on a five-point scale. This allowed the judges to assess the voice quality as +3, severely hypernasal, to −3, severely hyponasal, with a midpoint of 0 for normal. The velopharyngeal gaps were ranked in three categories for comparison; 0 as normal, 1 to 5 mm as moderate hypernasality, and beyond 6 mm as severe hypernasality. The judgments were compared between judges and between judges and degree of velopharyngeal gap. The reliability of the intrajudge ratings were also examined. These results and their importance to research are discussed.

Oral and Nasal Sound-Pressure Levels as Related to Presence or Absence of Velopharyngeal Closure

In this study, a comparison is made between oral and nasal sound-pressure levels for subjects with normal oral structures and complete velopharyngeal closure, for subjects who had undergone surgical repair of the palatal clefts and had complete velopharyngeal closure, and for subjects with repaired cleft palates but who lacked velopharyngeal closure as determined by cinefluorographic analysis. The study is also concerend with the relationship between SPL measures obtained for the right nostril as opposed to the SPL for the left nostril for all subjects. Statistically significant differences were found between the normal group and the cleft-palate group that lacked velopharyngeal closure and between the normal subjects and the cleft-palate group with no velopharyngeal gap. Other aspects of this study are presented.