Successful and rapid response of speech bulb reduction program combined with speech therapy in velopharyngeal dysfunction: a case report

A 16 year old female had suffered from nasal sound during conversation, and she was
very depressed and stressful due to her condition. The patient had a history of incomplete
cleft palate that was repaired 15 years ago. According to the patient, she had received
speech therapy at local clinic several times, but the patient believed that there
was no obvious change after the therapy. Clinical examination revealed that she had
seemingly insufficient palatopharyngeal tissue. Speech and voice assessment was conducted.
Speech resonance was measured using nasometer (Nasometer II model 6200-3, Kay Elementrics
Corp., USA) which can calculate a ratio of the acoustic energy collected by the two
separate microphones placed near to nose and mouth. This ratio means nasalance and
higher percentage indicates higher nasality. Simple vowels (/a/, /i/, /e/, /o/, /u/),
diphthong (/ja/, /je/, /wi/) and two passages were repeated for the test. As a result,
the vowel /i/ revealed severe nasalance (78.4 %, mean value of 22.3 %) and high nasalance
was found on /u/, /je/. Syllable repetition test indicated a hyper-nasality on oral
consonants (Table 1). Articulation differential test showed relatively high percentage of correct consonants
(97 %); however, a distortion of a specific consonant /s/ was found. Maximum phonation
time (MPT), sustaining phonation of a vowel sound /a/ as longer as patient can do,
was only 9.3 second which was short for her age representing an air escape thorough
a nasal pathway. Overall assessment indicated that minor velopharyngeal insufficiency
with the pattern of phoneme-specific nasal emission. Bulb type prosthesis with intensive
speech therapy was planned.

Table 1. Results of nasometric assessment before and after intervention

A careful impression with adequate extension to the soft palate was taken. Then, the
palatal portion of speech aid with posterior wire extension was fabricated by acrylic
resin. The appliance was delivered to the patient and initially she complained of
gaging reflex. After 2 weeks of adaptation period, pharyngeal portion was shaped using
high-viscosity impression wax during production of oral pressure sounds which cause
velopharyngeal function. Modification of the bulb was continued until remarkable reduction
in nasal emission was observed. This pharyngeal portion of the speech aid was replicated
in acrylic resin. The patient was recommended to have speech therapy once a week at
least. After the delivery of the appliance, the nasometric assessment was conducted
by 2, 4, 6, 8, 12, 16, 20 weeks, and the result was recorded (Fig. 1). The nasalance score was dramatically reduced in two weeks and the score was consistently
sustained. Wearing time reduction and speech bulb reduction was carried out by 12
and 16 weeks follow-up session respectively. After 20 weeks of follow-up, she eventually
did not want to wear the appliance any longer since the annoying problem of nasal
voice was disappeared.

Fig. 1. Changes of nasalance score for vowels before and after placement of the speech aids