Pediatric otolaryngological relations of velopharyngeal insufficiency

International Journal of Pediatric Otorhinolaryngology, 5 (1983) 199-212

199

Elsevier

Pediatric otolaryngological relations of velopharyngeal insufficiency * Jen/5 Hirschberg Heim P6I Hospital for Sick Children, Delej u. 10. H-1089 Budapest (Hungary)

(Received October 5, 1982) (Accepted November 3rd, 1982)

Key words: velopharyngealinsufficiency -- velopharyngealincompetence -- phonosurgery -- pharyn-

goplasty -- flap operation -- pediatric otolaryngology-- hyperrhinophony

Summary On the basis of his examinations, the author presents data and gives his opinion on the classification, etiopathogenesis, diagnostics, phonosurgery, and therapy of the otological complications of velopharyngeal insufficiency (VPI). VPI may be organic or functional, produced by congenital or acquired causes, due to paresis or local disorders, but most frequently occurs as a result of cleft palate. Usually, diagnosis is evident; however, the verification of the milder cases of anatomic disproportion a n d / o r muscular dysfunction is sometimes difficult. For the examination of dubious cases the author suggests, apart from the well-known methods (auditive evaluation, function tests, nasopharyngoscopy, velopharyngometry, supersound, X-ray, manometric measurements, speech intelligibility tests, acoustic analyses, etc.), electrophysiological and enzyme-histochemical measurements. Careful examination is most important, also on account of the possible indication of phonosurgery. An operation is to be proposed when a progressive neuro-myogenic process can thus be excluded, or when logopedic treatment is hopeless. The author has done 500 flap operations (as well as 2500 cleft palate and cleft lip ones) in the course of 30 years with a 9870 result of anatomical healing. According to the pathological situation he employed 10 variants of the operation. As a result, hyperrhinophony ceased or became minimal in 9070 of the cases; speech intelligibility was judged good or excellent in 74%. Functional effects can be influenced by the following: the width of the flap, the functional ability of the pharyngeal muscles, the

* Presented paper. "IQhirdInternational Conference in Paediatric Otolaryngology,Bath, 16-18 September, 1982. 0165-5876/83/$03.00 © 1983 ElsevierScience Publishers B.V.

200

cause of VPI, the patient's age, and the state of ears and hearing. In case of VPI otological and audiological examinations are routinely required. The author considers adenoidectomy and grommet-insertion to be alternative methods. One of the most important factors in achieving good results is teamwork, which the author discusses on the basis of the model developed at the Heim Phi Hospital for Sick Children, Budapest.

Introduction

Velopharyngeal insufficiency (VPI) is a border-line problem of several disciplines. Early detection of the symptoms, proper therapy and the assessment of the consequences of the disease is the combined task of pediatrician, otolaryngologist, phoniatrician, logopedist and plastic surgeon. However, for a more precise diagnosis, and to reveal the etiology of VPI, the collaboration of radiologist, orthodontist, genetician, neurologist and psychologist may also be necessary. Material

Our "experiences are based on a 30-year-work at the Department of ORL and Bronchology and at the Station of Phoniatrics and Pedoaudiology of the Heim Phi Hospital for Sick Children, Budapest [21]. During this period 3000 cleft palate a n d / o r lip operations--among them 500 pharyngoplasties--have been carried out. The Station of Phoniatrics and Pedoaudiology is an integrated part of the ENT Department, where care, research work and special diagnostics take place. Here 50-60 VPI patients without cleft are examined in one year. In more recent years there has been a more intensive collaboration with pedo-neurologists, enzymehistochemists, orthodontists, phoneticians and acoustic specialists. This team has examined 250 VPI and mentally retarded children from a neurological-psychological point of view [17], done electrophysiological examinations in 79 cases [19], performed cephalometry in 33 cases of Sedlh~kovh syndrom [33], and made several observations on new-born infants [18]. On the basis of our research we have created new speech intelligibility tests and worked out methods of acoustic analysis [ 12,16]. This paper discusses the problems of definition, symptoms, and diagnostic methods, and presents our classification, our medicinal and operative therapy especially emphasizing the pediatric otorhinolaryngological relations of VPI.

Definition

VPI means that the velum, regardless of etiology, cannot close the gap between the posterior pharyngeal wall and the velum. The term itself originates from Lermoyez [23], and the first mention of VPI can be found in Homer's Odyssey.

201

Symptoms The symptoms derive from the weakness of the functions in which the velum takes part, that is the malfunction of sucking, swallowing, speech, and middle ear ventilation. The consequences are aspiration, fluid-reflux through the nose, retarded speech development, hyperrhinophony, serous and frequent purulent otitis, and hypacusis. There is no universally accepted description of how the innervation of the velum and the muscles produce velopharyngeal closure and there are still many questions to be answered. Fritzell [8], Bell-Berti [1] and Honjo et al. [20] seem to prove convincingly that the m. levator veli palatini is the only muscle concerned in velopharyngeal closure. The m. tensor palatini only opens the Eustachian tube. Four cerebral nerves (V, VII, IX, X) play a role in the innervation. Among them, the facial and vagus are most important. In Sedlh~kov~t's opinion [31], there is a twofold innervation. The facial nerve directs the velum during articulation, while the vagus is in action during swallowing. These two systems can be damaged independently; digestive function, which is ontogenetically more ancient, suffers lesion more rarely. It is clear, on the basis of this theory, that the congenital disorders of swallowing are cured more easily that the younger function of phonation. Our own experience [ 18] proves that the aspiration of new-born infants more often than not ceases spontaneously, even though the infant can be fed only through a catheter for weeks or months. If there is no cleft palate, reflux, too, decreases gradually. Thus the most frequent, most persistent, and often the first or only symptom of VPI is hyperrhinophony. Sometimes, years later, only phoniatric examination explains the origin of infant asphyxia.

Diagnostics The 3 main bases of diagnosis are: correct anamnesis, judgement of velum function during phonation, and auditive evaluation of rhinophony. In every day practice VPI can be easily diagnosed in most cases with these 3 main elements. But for greater certainty, exactness and more refined diagnosis or documentation, several other methods may help (Table I). These methods can be used to define (a) the fact or degree of dysfunction, (b) pathological (nasal) air-flow, (c) pathological speech and voice tone, (d) tube function, and (e) to explore etiological factors, and (f)judge teachability. By the latter we assess in the case of maximum innervation, and by the help of various technical tricks, the improvement of hyperrhinophony. The speed with which new reflexes are created, their stabilization and unconscious performance which may follow within days, i.e. the success of conditioning, are characteristics of teachability. Two factors define the methods to be proposed: (a) the character and form of the disorder, i.e. the question how well the case can be judged by simple inspection or auditive observation, and r(b) the problem to be solved. In most cases complementary examinations are needed in the interest of etiology, prognosis, indication and effect

202 TABLE I DIAGNOSTIC METHODS IN CASE OF VELOPHARYNGEAL INSUFFICIENCY Documentation of type and degree of VPI Direct nasopharyngoscopy Photography Nasopharyngometry X-ray methods Special pictures Tomography Cinefluoroscopy Combined, with photoelectric method Contrast material Xeroradiography Supersound Measurement of pathological air-flow through the nose Manometry Aerodynamic methods Nasal vibration indicator Speech and voice examinations Auditive observation Functional tests Speech intelligibility and articulation tests Acoustic analysis Sonography LTAS Summation spectrography Measurement of tube function Audiometry Tympanometry Assessment of etiological factors EMG Skeletal, velopharyngeal and lingual myography (interference analysis) Motor conduction velocity Distal latent time evaluation Combined tests (Tensilon, d-tubo-curarin, etc.) Acoustic reflex test Enzyme examinations Cranial X-ray, CT Biopsy Light-microscopy Electron-microscopy Histochemistry Intelligence tests Methods for judging teachability IQ tests Motor tests Motoscopic tests Personality tests Ability to cooperate

203 of phonosurgery, and other therapy. It is useful to choose methods which approach the degree, results and cause of VPI from different angles, in order to get information from many viewpoints about our patient. Apart from direct endoscopy, we most frequently use X-ray, speech intelligibility tests, tympanometry, and electrophysiological methods. These methods are complemented, if needed, by manometric measurements, acoustic analysis, certain physiological tests, impedance audiometry, and the histochemical and microscopic examination of muscle tissue obtained through biopsy. The above-mentioned methods are necessary for documentation, statistical analysis, and especially in the absence of obvious paralysis or local change (overt or submucous cleft, Fig. 1.; defect; shortening). When the symptoms of insufficiency are present without any obvious pathology in the pharynx, we have to think of anatomical disproportion or muscular dysfunction. In such a case length and function of the velum or, for that matter, the size and depth of the epipharynx are not in proportion. In this connection Cooper's [2] simile about the door and the frame is very witty and appropriate. The d o o r - - t h e velum--does not shut well if it is too small for the frame or if the frame--the epipharynx--is too large for the door. Such relative VPI can be due to formes frustes of congenital anomalies or syndromes, discrete encephalopathy, or myopathy. Considering all this we emphasize the significance of 4 methods which have been

Fig. 1. Typicalviewof submucous cleft palate.

204 successfully used in our department, and due to which we can present some new data to the literature until now. On the basis of the American Templin-Darley test [35] we have composed a speech intelligibility and articulation evaluation method. We have put together 5 word lists for different ages. The lists of 50 one- or two-syllable words proportionally comprise all the sound in various acoustic environments. In order to define therapy and to judge the optimal time for phonosurgery, the evaluation of the speech intelligibility of 4-5-year-old children is most important. The examined child reads or repeats onto tape one of the lists. Then, 6 listeners, to whom the words are unknown, write down the replayed recording. From the average of correct answers speech intelligibility can be judged. In another test, following a similar method, the listeners judge the intelligibility of six sentences (about 50 words) from different children's stories. Sometimes the two tests have different results, e.g. with respect to the use of phonemes in continuous speech as opposed to words; thus the tests complement each other. Having evaluated 100 tests [12], we have also stated that the auditive judgement of experienced logopedists (based on a 4-degrees scale) most exactly coincides with the scores of our tests. In our opinion, 94-100% intelligibility can be evaluated as excellent, 80-94% as good, 64-80% as acceptable and less than 64% as bad. These results coincide with the findings of well-trained Iogopedists, who did not know about the scores of our test. To assess craniofacial structure, r6ntgenographic cephalometry is suitable [28,29]. We have defined by such cephalometric measurements, that the open mouth and the filtrum-shortening of the patients suffering from Sedlh~kov~ syndrom is only illusory: a deep bite caused by dysmorphy of the carniofacial complex is the primary disorder [33]. This result is important for orthodontic treatment. Teleradiography is especially reasonable in longitudinal measurements. From this we can draw conclusions of the expected development of the skull and the effects of the operations on skeletal growth. With the help of these examinations we demonstrated that flap-operation does not influence the configuration of the skull, as also shown by Pearl and Kaplan [27]. In border-fine cases, if the motility of velum cannot be assessed properly by routine examination, it is important to make an electrophysiologieal or electronmicroscopic examination of the tissue taken from the velum by biopsy. In the last 3 years 79 patients of between 2 and 14 years of age with border-fine cases of hyperrhinophony have been examined [19]. Electromyography was performed with the MEDICOR M G 42, a 4-channel chart recorder, using concentric needle-electrodes manufactured by Szabolcs Horv~th. Symmetrical skeletal and velar points were detected and measured. After interference analysis of the myograms the motor conduction velocity of nervus peroneus and medi~inus, and the distal latency time at the terminal non-myelinated end of the nerve fibers was evaluated. Occasionally, these evaluations were complemented by fight- and electron-microscopic examinations of skeletal and velar muscle-tissue obtained through biopsy, by impedance measurements, i.e. acoustic reflex tests, and by the d-tubo-curarin test which excludes myasthenia gravis. Using these methods in 49 of our 79 cases, the cause of VPI was verified as neuro-myogenic. According to the neurotopical classification, we

205 TABLE II CASES WHERE FLAP OPERATION IS CONTRAINDICATED OR TO BE CAUTIOUSLY CONSIDERED Progressiveprocess in intracranium Pathological nuclear processes Mononeuropathy,mononeuritis Myositis Myasthenia gravis Polyneuropathy Myopathy

diagnosed 23 cases as supranuclear, 10 as nuclear, and 6 as infranuclear damage. In 11 cases paresis proved to be myogenic. A detailed examination of VPI patients could demonstrate and point out 'hidden' diseases, such as a toxic neuropathy caused by drugs such as hidantoin, the joint presence--very rare in the literature--of nemalin myopathy and central core disease, or Kiloh-Nevin myopathy. The stapedius reflex may also help in localizing facial nerve lesion (paresis). As a result of all these examinations, pharyngoplasty aimed at improving speech was in certain cases contraindicated because of its danger or hopelessness. At times the patient was operated on after a different medicinal therapy as a result of its partial success or failure (Table II). In clarifying the etiology and type of VPI certain psychological tests may also help. By thoroughly performing the intelligence and motor tests, one can sometimes diagnose in the background of the so-called passive functional forms as organic disorders that cannot or only very painstakingly be identified by other methods. Signs pointing to these disorders are great deviation in part performance, strikingly faulty solutions of complex tests, grave motor retardation in relation to intelligence, and bad output in manual tests. With these examinations we have found in 18.4% of 250 mentally retarded children that their hyperrhinophony, thus far generally considered as functional, may often be due to infant age minimal cerebral damage (encephalopathia), which thus can be a joint, central cause of both oligophreny and hyperrhinophony [ 17].

Classification VPI is a polyetiological clinical condition. According to Minami and his coworkers [25], the palatopharyngeal structure has more than 50 abnormalities. Kaplan [22] places VPI patients without cleft into 4 categories: (a) anatomic disproportion with normal palate muscle function, (b) muscle dysfunction with normal anatomic proportions, (c) intermediate, and (d) indeterminate cases. On the basis of 30 years' experience and by the help of the above-mentioned diagnostic methods, we differentiate organic and functional types, which may be congenital and acquired, caused by

206 TABLE II1 FORMS AND CAUSES OF VELOPHARYNGEALINSUFFICIENCY Functional causes

Active Passive Neurogene (central,peripherical) Myogene

~/Acquired ~ _ ~ .Paresis

/

~ ~'Congenital

~ ~ ~

Encephalopathy Rudimenter paresis Nucleus aplasia sec. Moebius

Organic causes~x / / ~Local

~ Congenital ~

disorders~//

~

Cleft palate Submucous cleft Shortening D:ePto~iPhdYsnp~oportion

~ "Acqmred~

-

Destruction Cicatrization

local disorder or paresis (Table III). It is very important to differentiate the types of VPI in order to obtain a clear etiology, prescribe therapy including surgery, and set up a prognosis [15].

Treatment

Treatment of VPI depends on etiology. An operation is indicated for local defects such as trauma, cleft, tumor etc. In neuromyopathies drug therapy should be chosen, in functional disorders psychotherapy is adequate. Speech disorders can be cured in most cases by conservative treatment a n d / o r logopedy; however, in some cases phonosurgery is necessary.

Indications for surgery

Surgery is indicated in all cases of organic rhinophonia aperta, when certain pathological processes, e.g. progressive neurological diseases, can be excluded, and when there is no success to be expected from conservative treatment (i.e. when the distance between the velum and the posterior pharyngeal wall is longer than 6-8 mm during phonation).

207 The operation can also be done in multiply handicapped (both mentally, motorically, and speech-affected) children, but then more modest results should be expected. Before such operations, careful clinical examinations and tests are especially important. In the case of paresis of the central type a n d / o r decreased pharyngeal wall mobility, some improvement can also be expected, because of the mechanical effect of the tightened flap causing a decrease in air flow through the nose. We have the same opinion about cases of mental retardation and debility: one should try to improve what can be improved, namely speech. The minimum IQ necessary for the indication of pharyngoplasty is 50. In border-line cases conservative treatment is appropriate. Surgery can then be considered after 6 months when success is lacking. In what is called functional VPI, the operation is indicated if an organic background is proven. There are several methods of pharyngoplasty. The pharynx can be tightened: (1)

Fig. 2. Inferiorlybased flap one year after operation.

208 by bulging the posterior pharyngeal wall through muscle slinging or various implants (silastic, teflon, cartilage, etc.), (2) by prostheses, obturators (speech bulbs), (3) by lengthening the palate (push back), (4) by directly sewing together the velum a n d / o r the pharyngeal folds and the posterior pharyngeal wall, (5) by flap operation and (6) by a combination of the above methods. According to the character of the disorder, the state of the velum and the posterior pharyngeal wall, or the degree of VPI, we have developed and employed 10 operational variants [14]. These are partly well-known types of operations, partly modifications, or the result of our own research work. Most commonly we sew a mucosa-covered fibromuscular flap derived from the posterior pharyngeal wall on the denudated velum, or fix under 'door-frame' flaps, possibly in a bag prepared behind the uvula. When the velum is too short, and the velopharyngeal gap is thus large, we lengthen the velum by making an apron flap, this way securing a bigger receiving bed for the pharyngeal flap. This is the most secure, most frequently used, and thus far most successful variant. When there is a A defect on the soft palate, we sew together the posterior pharyngeal pillars, after mobilization, or turn out an apron flap from them, thus preparing the necessary receiving bed, which can be increased by simultaneously removing the large tonsils. When operating on a greatly destroyed velum, sometimes only the remaining intact side of the velum can be made suitable for receiving the pharyngeal flap. With the above variants the pharyngeal flap is always based inferiorly. In 15% of our ope.rations we have chosen to base the flap superiorly. Injecting teflon into the posterior pharyngeal wall has only rarely been done, and can only be suggested w i t h a duly mobile and moderately shortened velum. When deciding on the type of operation, the character of the disorder is also to be considered, but one should prefer to employ the variant proven to be best, and best practised (Fig. 2).

Results--surgical healing, speech results We have done 500 flap operations. In 490 patients (98%) there was anatomical healing (in 26 cases the flap healed partly or a little dehiscence developed, but even in these cases speech has improved). In 10 cases the flap became detached. Out of four reoperations, two were successful. In three further inoperable cases, we used the speech bulb to decrease hyperrhinophony [34]. Although generally flap operation is not risky when performed by well-trained hands, sometimes grave complications do occur. From the immense material of 645 operations, Croatto [3] reports 2 deaths; Grahan~ and his coworkers [9] have been compelled to postoperative tracheotomy in 7 cases out of 222. We have observed 2 serious complications, massive bleeding and aspiration. Both cases required tracheotomy. We had no lethal complications. One hundred cases out of 500 postoperative examinations are presented in Table IV. Functional results are given, separately evaluating rhinophony, articulation and intelligibility at least one year after the operation. Hyperrhinophony ceased or

209 TABLE IV FUNCTIONAL RESULTS AFTER FLAP OPERATIONS Hyperrhinophony

Ceased

45%

Minimal

45%

Moderate

10%

Intense -

Phonemes defective Articulation

Correct 42%

1-2 8%

3-4 21%

More

Speech intelligibility

Excellent 42%

Good 32%

Acceptable 21%

Bad 5%

29%

became minimal in 90%, speech intelligibility proved to be excellent or good in 74%. The relatively large number of articulation defects illustrates the necessity, or for that matter, the insufficiency of the postoperative logopedic treatment. Other authors [5,30] report about the same results, hyperrhinophony decreasing in 80%. We have evaluated functional results, and the most important circumstances influencing speech intelligibility by statistical analysis, using the least squares method in stating significance [13]. On the basis of these data, the improvement of speech depends on the following factors: the width of the flap, the functional ability of pharyngeal muscles, the cause of VPI (results are generally better in the case of anatomical disproportion than in that of muscular dysfunction), the state of the ears, hearing, and the patient's age at the time of the operation (results are better with young children). The practical experience of the surgeon, the competence of postoperative logopedic treatment, the patient's cooperation and intelligence can all b,e very important factors, but the site of basing the flap, or whether the operation is primary or secondary, do not influence effectiveness. Seventy percent of our operations were secondary ones after palatoplasty; 30% primary in cases without cleft (Table V). According to the literature and our results, on the basis of proper indication and due experience of the surgeon, pharyngoplasty improves speech and good results can be promised for intelligent, young children. In our opinion the age between 4½ and 5 is optimal for the operation. In later years speech disorder becomes more and more fixed, and is less influenced by surgery, or not at all.

TABLE V DIAGNOSIS IN CASES OF 500 PHARYNGOPLASTIES Cleft palate Submucous cleft Shortening Deep epipharynx, anatomical disproportion Paresis, muscular dys~function t Destruction

350 50 63 19 16 2

210 Otology,

audiology

It is well-known and also proved by our experience that in cases of VPI, the number of pathological changes in the middle ear is high: 30-76% [4,10,26]. In a late postoperative survey, tympanometry showed a pathological state in 36% (Table VI) of our cases. Tube dysfunction is mostly responsible for ear pathology. The role of food and drink reflux can be ignored. Neglecting the treatment of ear disorders and tardy diagnosis not only set back logopedy, but also deteriorate the possible effect of pharyngoplasty, eventually resulting in tympanosclerosis, and irreversible hearing impairment. In our opinion, during habilitation, one should strive to improve hearing as well, this being one of the basic conditions of successful speech teaching. Thus, the maximally non-committal attitude has no justification. Ear pathology should be cured as soon as possible, and in case of pharyngoplasty by all means prior to surgery. The alternatives of adenoidectomy, lateral adenotomy or ventilation tube insertion have still not been decided [11]. Our own practice [6] has been the following. In case of frequent upper airway inflammation or recurrent sinusitis and purulent otitis, we carry out adenoidectomy, if necessary after mastoid operation. If speech should deteriorate we suggest flap operation. Before pharyngoplasty the removal of the adenoid is indicated, as a rule. This also helps the incision o f the flap. In the case of chronic serous otitis, when dysfunction of the tube is predominant, we prefer the insertion of the middle ear ventilation tube. Pharyngoplasty does not influence hearing or the state of the ear, as also shown by Pearl and Kaplan [27], Subtelny and Nieto [32], and Leworthy and Schliesser [24]. Early diagnosis of ear pathology and the soonest possible objective evaluation of hearing is very important. For this reason we urge the audiological screening of all VPI new-born infants, to be repeated at the age of 6 - 8 months. Impedance audiometry has a great significance. This examination may be carried out on infants too, when necessary, with general anesthesia [7].

TABLE VI TYMPANOGRAM TYPES OF REEXAMINED PATIENTS OPERATED ON -- WITH PHARYNGOPLASTIES -- FOR VPI Number of ears

%

A

128

64

B

32

16

Ct C2

16 24

8 12

- 199 mm H20 < C t < C2 ~< - 200 mm H 20.

- 100 m m

H20.

211

Conclusions Pediatric ORL deals with various problems and forms of VPI. When discovering these complaints in infants, the parents or GP will most often consult a pediatric ORL or phoniatrician. That is why we have dealt with the above-mentioned most important problems of diagnostics, therapy and ear pathology. The pediatric ORL may undertake the flap operation himself, on the basis of proper training, experience and functional knowledge. The specialty of the surgeon is not relevant, as long as he secures the cooperation of the representatives of all the professions necessary for the complex rehabilitation of the patient during and after the operation. Finally, we would like to stress the importance of teamwork, the pediatric clinic background and the collaboration of medical specialists and speech therapists.

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