Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_33_библиотеки_им_акад_М_И_Перельмана
.pdf
Impact of VPI on Articulation
Not all individuals with cleft palate develop deviant speech
articulation. For many, the initial palatoplasty provides an adequate VP
closure mechanism that minimizes the risk of early or prelinguistic
speech sound mislearning. Such early mislearning (of airflow direction
and articulatory placements) may be subsequently incorporated into the
child's phonemic inventory and early lexicon. (See Chapter 4 in this text
and Peterson-Falzone, et al., 2010, Chapter 7, for a more comprehensive
review and summary of early speech development.) Based on their
review of the literature, Peterson-Falzone et al. (2001, 2010) concluded
that normal articulation can be expected in approximately 25% of
preschoolers with cleft palate who receive team care, and some
individuals continue to demonstrate articulation problems in
adolescence. Many of these misarticulations will be due to dental and
occlusal problems. Lohmander (2011) summarized the findings from 34
studies of speech outcome after primary surgery over a 25-year period
(1984 to 2010); all of these studies employed (audio or video) speech
recordings for data collection and analysis. Participants included
preschoolers through young adults, and nine different languages were
represented. Speech outcomes were categorized in terms of (1) speech
accuracy (presence or absence of audible nasal emission, hypernasality,
and articulation errors) and (2) speech intelligibility. The most
information was available on 5 year olds, and the findings were
generally compatible with outcomes reported in frequently referenced
studies based on live ratings and chart reviews. Namely, 50% to 60% of
3 year olds should have good speech; and 60% to 70% of 4 to 5 year olds
and 70% to 80% of 6 to 8 year olds should have normal speech.
Approximately 80% of 10 to 16 year olds and 90% of young adults
should have good speech; /s/ distortions were the most common
residual problem. Clearly, these data tell us that cleft-related speech
errors decrease with increasing age. Whether this reflects improved
surgical techniques, appropriately timed and executed speech therapy,
or a combination of both cannot be determined without a more robust
evidence base. What is apparent is that up until the midteens, many
individuals with repaired cleft palates continue to need the services of
the speech-language pathologist (SLP).
144
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
The perceptual impact of VPI on articulation in speakers with cleft
palate is commonly acknowledged among SLPs and other professionals
involved in cleft care. At a global or superficial level, it includes the
familiar triad of “nasal emission,” “weak pressure consonants,” and
“compensatory articulations.” Although accurate, this at-a-glance
categorization of cleft palate speech deviations is of lile use clinically
in the speech management of VPI. For evaluation and differential
diagnosis and for speech treatment planning and effective delivery, a
more in-depth understanding of cleft palate misarticulations is
warranted. Description of these speech sound disorders is the focus of
the remainder of this chapter.
Nasal Emission
Nasal emission (NE), like hypernasality, results from inappropriate
coupling of the oral and nasal cavities. Nasal emission is the airflow
deviation or airflow direction error that affects the high pressure
consonants (the stops, fricatives, affricates) that require oral airflow
under pressure. In nasal air emission, the nasal and oral cavities are
“coupled” or united as one, rather than separated to allow for oral
direction of the air stream. Airflow that normally is directed and
emied orally escapes or is sent into the nasal cavity and is released
nasally (Box 5-1).
Box 5-1
Hypernasality Versus Nasal Emission
Although both hypernasality and nasal air emission result from
abnormal or inappropriate coupling of oral and nasal cavities, they are
distinctly different parameters of velopharyngeal inadequacy and they
affect different sound classes. Nasal air emission is not a resonance
disorder.
The usual causes of this inappropriate oral-nasal coupling are VPI
(coupling via the VP port) and fistulas (coupling via the oral cavity).
Depending on the extent of VP opening and the forcefulness of the
airflow, there may be concurrent oral and nasal air emission or speech
airflow may be exclusively (100%) nasal.
145
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
Nasal emission (NE) comes in a variety of forms that are perceptually
distinct. NE can be audible or inaudible. Audible nasal emission (ANE)
can be nonturbulent or turbulent, and whether nonturbulent or
turbulent, ANE can be obligatory or learned. Obligatory nasal emission
and learned nasal emission errors can be distinguished from each other
based on their perceived error paerns. Let us now take a closer look at
these nasal emission variables.
Error “paern” is not the same as error “type.” For example, the gloal
stop is an error type. A speaker who uses gloal stop to replace /p, b, t,
d, k, g/ has an error paern affecting the entire class of stops. Similarly,
the nasal fricative is an error type. A speaker who uses nasal fricative to
replace only certain consonants (e.g., /s/ and /z/) has a phonemespecific error paern. This distinction is discussed further in the section
on learned nasal emission, later in this chapter.
Inaudible Nasal Emission
Inaudible NE is nasal emission that is not heard but can be visibly
detected by holding a dental mirror or other small mirror or reflector
just below the nostrils. The emied nasal airflow will fog or mist the
mirror. Although not perceptually disruptive to speech, inaudible NE
should be flagged in the diagnostic process because it may be an
indicator of incipient VPI or airflow through an oronasal fistula that
could affect or reduce oral pressure, impair veoopharyngeal activity, or
aggravate existing VPI (Diah et al., 2007; Isberg and Henningsson,
1987). It is also possible that the inaudible emission may be a chronic
mild residual of the repaired cleft palate and of no consequence to
speech.
Audible Nasal Emission and Nasal Turbulence
As defined and used throughout this text, audible nasal emission is audible
frication heard when air under pressure flows through the nasal cavity
meeting variable degrees of nasal cavity resistance. Audible nasal
emission is transcribed by placing the ExtIPA diacritic above the
affected pressure consonant (e.g.,
) (Duckworth et al., 1990). Nasal
turbulence is audible snorting with or without associated nasal air
emission, although the overriding perceptual quality is the snorting.
146
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
Nasal turbulence is transcribed by placing the ExtIPA diacritic for
“velopharyngeal frication” above the affected target (e.g.,
).
ExtIPA is an abbreviation for Extensions to the IPA (International
Phonetic Alphabet). It consists of a group of phonetic symbols and
diacritics useful in narrow transcription of speech in special
populations, including persons with cleft lip and palate or other causes
of velopharyngeal inadequacy.
We acknowledge that both audible frication and snorting are
characterized acoustically by aperiodic noise, and therefore both are
“turbulent,” as pointed out by Zajac (2015). Perceptually, however, there
is long-standing and widespread use and acceptance of the term “nasal
turbulence” to label the snorting, both in research involving listeners'
judgments and in clinical practice (Chapman et al., in press;
Henningsson et al., 2008; John et al., 2006; Peterson-Falzone et al, 2006,
2010; Sell et al., 1999; Trost-Cardamone, 2013;), and Sweeney (2011).
This underscores the utility of audible nasal emission
(nonturbulent)/nasal turbulence (turbulent) as a salient perceptual
dichotomy. In addition, “turbulent/nonturbulent” is more aesthetically
pleasing than “snorted/nonsnorted”!
Several authors have identified the VP port as the source of this
“snorting” turbulence. Based on radiographic images, Trost (1981)
identified velar “fluer” frication at the velopharyngeal port as the
source of turbulence and, based on its location and perceptual quality,
labeled this a “posterior nasal fricative.” Because of its articulatory
gestures, she also offered the term “velopharyngeal fricative.”
Subsequent reports by Kummer and colleagues (1989, 1992, 2003)
demonstrated, through imaging studies, that the VP port is the source
of the nasal turbulence (which they termed “nasal rustle”) and that
nasal turbulence is associated with smaller VP gaps. ANE
(nonturbulent) is generated with a more open VP port. Similarly, the
report by Zajac (2015), based on acoustic and pressure-flow data,
confirmed the VP port locus of the snorting.
SLPs experienced with cleft palate speech have noted the variable
auditory perceptual qualities associated with nasal emission including
the variable snorting. Many labels have been used to identify this
147
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
perceived snorting behavior, dating back to at least 1943. Some of these
are listed (and noted with an asterisk) in Table 5-1. Although nasal
turbulence is the more frequently used term both in clinical practice and
in the published literature at this time, a lack of standardized
terminology for describing nasal airflow deviations persists (Box 5-2).
TABLE 5-1
Terms Used to Label the Various Auditory Perceptual Qualities
Associated With Nasal Emission
REFERENCE TERM
Backus et al., 1943
Nasal snort
*
Van Riper and
Irwin, 1961
Hissing noise
Nasopharyngeal snort
*
Van Demark, 1964 Distortion-nasal and substitution-nasal
Morley, 1970 Nasopharyngeal snort
McWilliams and
Phillips, 1979
Nasal turbulence (as distinguished from nasal emission)
Trost, 1981
Posterior nasal fricative* (based on perceptual quality)
Velopharyngeal fricative (based on articulatory gestures at the velopharyngeal port)
Kummer et al.,
1992, 2003
Nasal rustle* (produced with a “small” velopharyngeal gap compared with a more open
port associated with audible nasal emission)
*
Terms used to describe the “snorting” turbulence quality.
Box 5-2
Audible Nasal Emission Versus Nasal
Turbulence
To reiterate, as used in this text, “audible nasal emission” is nasal
emission that has no snorting sound; it is nonturbulent nasal emission.
“Nasal turbulence” is the snorting sound.
In clinical practice, it is important to distinguish between audible
nasal emission and nasal turbulence because this distinction provides a
clue to VP closure behavior. As just discussed, nasal turbulence is
associated with a smaller or narrow VP gap, whereas audible nasal
emission is generated with a more widely open port (Fig. 5-5A). Such
differences in VP closure behavior often mandate different
management, as discussed in Chapter 10.
148
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
FIGURE 5-5 Nasal emission variables.
Coproduced Nasal Emission Versus Nasal Fricative Replacement
of the Target
It is important to distinguish audible nasal emission or nasal turbulence
that accompanies or is coproduced with high pressure consonant
targets from audible nasal emission or nasal turbulence that is
associated with a nasal fricative replacement or substitution of the
target consonant (see Fig. 5-5B). With coproduced audible nasal
emission or nasal turbulence, the target consonant, although distorted,
still is identifiable. When a nasal fricative is produced, the target is not
perceptually identifiable; it is replaced by the nasal fricative
articulation. (See descriptions of the nasal fricative later in this chapter.)
Obligatory Nasal Emission Versus Learned Nasal Emission
Whereas hypernasality in speakers with repaired cleft palates is almost
always obligatory or has a physical basis, nasal emission can be either
obligatory (passive) or learned (i.e., active; meaning that it has no physical
basis) (see Fig. 5-5C).
Obligatory Nasal Emission.
Obligatory nasal emission is physically based and may result from the
following factors:
149
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
1. VP insufficiency, such as seen in patients with an unrepaired or
inadequately repaired cleft palate, or mechanical interference to closure,
resulting in widespread, pervasive NE affecting all pressure consonants
in the speaker's inventory, and typically accompanied by pervasive
hypernasality
2. VP incompetency as in the dysarthrias of closed head injury in which
NE affects all pressure consonants but may be weakly realized and is
also accompanied by pervasive hypernasality
In linguistic terminology, “realized” is used to mean “produced.”
3. Postoperative or residual oronasal fistulas in which we can see a
correlation between the location of the fistula and the error paern
observed (i.e., the specific sounds affected by the fistula).
Obligatory ANE requires physical management (either through
surgery or prosthetic appliance management).
Learned Nasal Emission.
Learned (active) nasal emission occurs in spite of a capable VP closure
mechanism. The speaker intentionally directs airflow through the VP port.
Two error paerns that you are likely to encounter in clinical practice
are phoneme-specific nasal emission and persisting postoperative nasal
emission. These paerns are discussed in the following paragraphs.
Because learned nasal emission typically affects a specific high
pressure consonant or small subset of pressure consonants, usually the
sibilant fricatives, it has come to be called phoneme-specific nasal emission
(PSNE).
Ruscello (1991) termed this paern “context specific nasal emission.”
According to Harding and Grunwell in the United Kingdom (1998),
“Strategies employed in early speech inevitably affect phonological
processes” (p. 331). These investigators preferred to categorize these
errors as “process specific” and not phoneme-specific because a class of
consonants (e.g., fricatives) can be realized by one error type (e.g., nasal
fricative for all fricatives or all sibilant fricatives). Both terms describe
150
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
the same kind of mislearning that involves intentional nasal emission
or turbulence.
Phoneme-specific nasal emission is probably the most common learned
NE error paern (Box 5-3). It is a very important paern for you to
understand because, although a cleft speech characteristic, it is not
limited to patients with cleft palate. PSNE also occurs in individuals
without clefts who have normal VP closure ability, as well as in
speakers with adequately repaired cleft palates (Peterson-Falzone, 1975;
Peterson-Falzone and Graham, 1990; Trost, 1981, Trost-Cardamone
1988). PSNE is selective nasal emission in that it affects production of
certain high pressure consonants, while the remainder of the high
pressure consonants in the speaker's inventory are produced with
normal (oral) direction of airflow. The phonemes most vulnerable to
PSNE are the sibilant fricatives and affricates /s, z,
, , , /. We usually
perceive audible nasal emission or nasal turbulence coproduced with the
target or a nasal fricative replacement for the target, as described later in
this chapter. Typically, there is no associated hypernasality; there may
be intermient assimilation nasality affecting vowels next to the
consonant phoneme(s) affected by PSNE. Because /s/ is almost always
affected and is the most frequently occurring sound in spoken English,
when a child with no obvious physical signs of clefting presents with
phoneme-specific, clinicians unfamiliar with this paern think there
must be some type of submucous cleft. Importantly, because this error
paern is learned, PSNE is corrected through speech therapy and does
not require or respond to surgical management.
Box 5-3
Learned Audible Nasal Emission or Nasal
Turbulence: Different Presentations
Perceptually, learned nasal emission can be realized as nasal emission
that is coproduced with an oral pressure consonant or in a nasal
fricative substitution for the pressure consonant, either of which may
have associated nasal turbulence or snorting.
Persisting postoperative nasal emission is nasal emission that persists in
speakers with repaired cleft palate and adequate VP closure ability. In
151
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
other words, for some speakers, the early-learned option or strategy of
directing air nasally to produce pressure consonants may be
incorporated into their phonological system, and they continue to direct
airflow nasally. In our experience, persisting postoperative nasal
emission differs from nasal emission that is phoneme-specific in that it
is not restricted to a certain sound class or group. It can affect any of the
high pressure consonants, depending on which early developing
sounds were “learned” with nasal emission. Like phoneme-specific
nasal emission, persisting postoperative nasal emission is perceptually
realized as nasal emission coproduced with the target or as a nasal
fricative replacement of the target.
Nasal Emission: Conclusion and Recommendation
Much of the evidence on the perceptual characteristics of nasal emission
comes from our clinical experience and from anecdotal reports and
informal exchange among clinicians. Both of these learned paerns
warrant further definition through clinical documentation and
systematic study. Nevertheless, you should keep in mind that not all
nasal air emission has a physical basis. Unless you are familiar with these
paerns, confirmation of suspected learned nasal emission by a cleft
palate team or an SLP experienced in cleft palate management is
strongly recommended and is preferred over referral to a plastic
surgeon or ENT physician who may not be involved with a team or
knowledgeable regarding best practices for cleft care.
Figure 5-6 presents a schematic illustration of the potential sources of
nasal emission. In Chapter 8 we describe clinical assessment procedures
to guide you in differential diagnosis of nasal emission paerns, where
you will learn that the target sounds affected by nasal emission depend
on the source of that nasal emission. There is a relationship between the
source of nasal air escape and place of articulation of affected
consonants.
Audio 5-4
provides samples of three speakers with different sources
of nasal air emission. Speaker 1 has pervasive nasal turbulence,
generated at the velopharyngeal port as a result of an unoperated
submucous cleft palate. Speaker 2 has nasal air emission audible on /p,
b, t, d/ because of an anterior oronasal fistula; other pressure
consonants (e.g., /f, v, k, g/ are not affected. Speaker 3 has phoneme-
152
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
specific nasal emission that affects the sibilant fricatives and affricates
but none of the other high pressure consonants in his inventory.
FIGURE 5-6 Sources of nasal emission. A, Nasolabial fistula.
B, Anterior oronasal fistula. C, Posterior oronasal fistula. D,
Velopharyngeal port (VP insufficiency, VP incompetency, VP
mislearning).
Weak Pressure Consonants
When there is a leak in the aerodynamic system, (e.g., nasal airflow due
to VPI or a sufficiently large fistula), oral pressures for speech will drop,
just as water pressure drops in a leaky hose. Weak pressure consonants
are the result of this pressure drop that reduces or eliminates the
153
t.me/Dr_Mouayyad_AlbtousH
https://t.me/medicina_free
Соседние файлы в папке Библиотека им академика М.И. Перельмана