SECONDARY LENGTHENING OF THE SOFT PALATE USING MILLARD'S ISLAND FLAP TECHNIQUE. By R. DIJKSTRA. Zwolle, The Netherlands

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1 SECNDARY LENGTHENNG F THE SFT PALATE USNG MLLARD'S SLAND FLAP TECHNQUE By R. DJKSTRA Zwolle, The Netherlands MST investigators nowadays are inclined to the opinion that velo-pharyngeal closure during normal speech is brought about by a flap-like movement of the soft palate, rather than by sphincteric action. Thus the soft palate is raised by contraction of the levator muscles, fibres of which cross and ioin in the middle third of the palate. They form a muscular sling with both ends attached to the base of the skull. n contraction of this loop the palate is pulled up and backwards, drawn up in its middle third to touch the posterior pharyngeal wall at, or just above, the level of the first cervical vertebra. The posterior third of the palate generally remains flaccid and hangs down, screening the actual area of closure from the examining eye. f, for some reason, closure in this way cannot be easily effected, other muscles may come into play. The palato-pharyngeus muscles (Braithwaite, 62) and possibly the uppermost fibres of the superior constrictor of the pharynx (Whillis, 3 o) can pull the palate backwards, and at the same time narrow the pharynx in its lateral dimension. n this way they play a compensatory role where the valve mechanism, as operated by the levator muscle, is not competent. n the congenital cleft palate it is found that fusion of the paired muscles has not taken place. Apart from this abnormality, or perhaps secondary to it, there is a lack of development in the antero-posterior dimension. Normally the aponeurosis, formed by the tendinous fibres of the tensor palati muscles, forms about one-third of the antero-posterior length of the soft palate. n the cleft palate this aponeurosis has not developed to this extent, according to Veau (3), owing to lack of muscle pull during the foetal stage. As a consequence, the levator muscles, partly attached to this aponeurosis, partly inserting their fibres in the tissue of the free edges of the cleft, run in a more forward direction in the cleft palate (Ruding, 64) than they do in the normal palate. When a cleft of the palate is simply sutured, the position of the levator muscles is not altered and the active part of the palate, as a result, lies too far forward. The levator bundle is tethered to the hard palate on shorter rein than normally, as the underdeveloped aponeurosis allows less muscle movement. Lengthening of the anterior third of the palate by freeing the aponeurosis from the posterior rim of the hard palate is the aim of the lengthening operations, both of primary closure and of secondary procedures. To make the most of this lengthening, after detaching the aponeurosis from the posterior rim of the hard palate, the overlying nasal mucosa has to be divided and tissue has to be added to close the resulting defect in nasal mucosa. A number of procedures have been devised, making use of either grafts or flaps (Dorrance and Bransfield, 43; Sanvenero-Rosselli, 55 ; Cronin, 57; Millard, i62, 63 ; Honig, 63). Whether such methods, applied at the time of primary closure of the palate, give speech results superior to the simple methods such as the V-Y type of repair, in which nasal mucosa is not divided, is still not proven conclusively. f shortness of the palate plays a role in velo-pharyngeal incompetence after simple repair of a cleft palate, the same more radical methods can be used to produce secondary lengthening, in order to attain a normal closing mechanism in speech. 2B ~

2 ~4 BRTSH JURNAL F PLASTC SURGERY t is thus necessary to asccrtain that the palate is short with respect to the anteroposterior diameter of the pharynx, and that there is good muscle action. This is best done by lateral radiological examination as described by Calnan (56). We use four views :. The soft palate at rest, while the patient is breathing through the nose or saying "m ". Pronunciation of this nasal consonant does not involve complete relaxation of the soft palate, but comes near to it, and is easy to achieve in children. 2 and 3. Phonation, using the sustained vowels "u " and "i" These normally involve complete velo-pharyngeal closure and are diagnostically the most important. n cases of insufficiency, a gap is seen between the active part of the soft palate (levator ridge) and the posterior pharyngeal wall, and the diameter of this gap is measured. 4. Producing the consonant "s ". This, like blowing, often involves a more pronounced elevation of the soft palate, due to stronger muscle action and perhaps also higher intra-oral pressure. Closure can sometimes be seen in patients who display minor to moderate nasality in speech. Use of contrast media, at least in children, is not necessary and can even jeopardise the co-operation of the patient, which is so important. TABLE Number of ] mmobile No measurepatients / ncom ~etence in mm. palates ments possible Moderate to severe nasality Slight nasality,. 2 No nasality 5., t is appreciated that this only gives a two-dimensional impression of a threedimensional structure and that, for instance, the width of the pharynx is not taken into account. However, a positive correlation between the degree of nasality in speech and the lateral radiological findings on phonation was found by others (Bj6rk and Nylen, 63 ; Hagerty and Hofmeister) and could also be demonstrated by us, as will be shown. An unselected, consecutive series of 73 patients was reviewed, in whom closure of a cleft palate was carried out by Dr J. Hage between 54 and 6. n 63 patients the operation was performed before they were 8 months of age ; the remaining o were between 2 and 5 years. A minor degree of nasality, only discernable by the trained ear, was found in io patients (3 per cent) and a definite nasality, which could be classified as abnormal speech by the layman, was found in 7 patients (24 per cent). This makes a total of 27 patients with varying degrees of nasality in speech. n 24 of these patients lateral radiographs were obtained. The findings in these 24 patients are enumerated in the Table. Radiographs were also made in 5 random patients from this series, in whom no nasality in speech could be demonstrated. The Table gives the distance between the levator ridge and the posterior pharyngeal wall as measured on the radiographs made while phonating the vowel "i ". n the three cases in which no accurate measurements could be made, the soft palate had been tethered to the posterior pharyngeal wall by a pharyngeal flap.

3 SECNDARY LENGTHENNG F THE SFT PALATE 115 When a radiologically appreciable gap is found, speech training alone will not be sufficient to overcome the abnormality. According to Van Gelder (165) this is the case with gaps of 4 mm. or over on phonation of" i ". Thus far in this department, surgical treatment for residual nasality after palate repair had consisted of a pharyngeal flap operation. The flap was usually raised on a superior base and attached at the posterior part of the soft palate, without concomitant push-back of the soft palate (Sercer, 135). This simple flap makes the naso-pharyngeal orifice smaller, partly by sheer bulk of the flap and partly by contraction of the donor defect on the posterior pharyngeal wall. Thus the compensatory sphincter mechanism FG. FG. 2 To show dissection of island flaps with neurovascular bundles. gets a better chance of closing the naso-pharyngeal leak. n due time the flap contracts to a short narrow band, and ultimately it is impossible to say whether it was originally based superiorly or inferiorly (Blackfield et al., 63 ; Skoog, 165). Speech results are not always found to be satisfactory with this procedure. Lengthening of the palate, aiming to restore the flap-like movement, seems to be a more logical approach to treatment for post-operative nasality. t was decided to adapt Millard's island flap procedure to this end. This operation was carried out in 17 patients, who had nasality following primary closure of a cleft palate. Twelve of these were patients from the above-mentioned series of reviewed cleft palate patients, while five had been operated on elsewhere. Their age ranged from 5 to 18 years. The technical details of the procedure are described

4 6 BRTSH JURNAL F PLASTC SURGERY by Millard. A few points, however, ought to be mentioned. n four early cases the island flap was cut from the anterior part of the muco-periostcum of the hard palate, and bascd on two neurovascular bundles, which as a consequence had to be dissected backwards from the undersurface of the remaining muco-periosteum (Fig. 2). n two cases, post-operative loss of gained length occurred, probably duc to contraction of the flap. This was attributed to ischacmia due to vascular trauma, sustained during the dissection. ne of these cases also developed a fistula in the denuded anterior part of the cleft. n the remaining cases a unilateral island flap was always used, overlying the whole length of the palatine vessels (Fig. ). Contraction of these flaps did not occur. TABLE Age at operation PRE-PERATVE Nasality Velophar. distance in mm. on X-ray Nasality Velophar. distance in mm. on X-ray i $ PST-PERATVE Mm. width of [ Fate of flap island flap as judged used by clips x r " i; 4 o b o r + o ' ( ( contraction contraction Nasality : + -- moderate ; + + = severe. To follow up the fate of the flap and its contribution to length gained, the island flap was marked with silver clips just within its anterior and posterior border, as described by Hage (66). These clips could be traced in cases on post-operative radiographs. n all cases measurements were made of the distance between the levator ridge and the posterior pharyngeal wall, on radiographs taken during phonation. The results of pre- and post-operative radiological examinations and speech assessment are shown in Table. n patients io and 12 a contracted pharyngeal flap tethered the posterior part of the soft palate to the posterior pharyngeal wall and this made pre-operative radiological measurements impossible. n patient, no elevation of the velum was obtained on vowel sounds. However, as mobility was good on " s ", lengthening was carried out. Subsequently a Hynes' pharyngoplasty (Hynes, 5 o) was done to overcome the remaining defect. Although the formed ridge could not be seen on later radiographs, narrowing of the pharynx was obviously maintained and closure was effected on" s ". Speech was ultimately improved. t will be seen that in this last patient, although the insufficiency measured 15 mm., an island flap measuring only ram. across was used. There are two reasons for this :

5 SECNDARY LENGTHENNG F THE SFT PALATE 117. Mucoperiosteum is in limited supply. When also some collapse of the palate exists, it is often not possible to obtain an island flap wider than to Z mm. particularly as it is also advisable to leave the scar tissue overlying the cleft in situ. Two flaps can then be raised on each side of this area. The island flap is formed from one, the other used by transposing it through to cover the island flap on its oral side. x. The second consideration applies to all lengthening procedures2and requires some elaboration. The soft palate is detached from the posterior rim of the hard palate by cutting through the aponeurosis and nasal mucosa after elevation of the mucoperiosteal flaps. t then retracts until the cutting knife has reached the lateral pharyngeal wall. This retraction must be largely caused by the muscles of the soft palate. The mechanism is probably that they, particularly the levator muscles, now take up a normal transverse course instead of the abnormal forward position seen in the cleft palate patient. This is in agreement with observations in three cases of congenital short palates, where we performed a lengthening operation. Retraction was much less than in those cases where a cleft previously existed and where the retraction averages mm. t stands to reason that pushing the palate further back than it will go spontaneously, will not improve active velo-pharyngeal closure, because on contraction the levator bundle will tend to attain its predetermined shortest transverse course. t appears that a" pushback" of more than mm. does not add any effective lengthening. This limitation of effective lengthening has been found by others as well (Trauner, 156 ). Writers who claimed to obtain lengthening of 15 mm. or more in some cases, always refer to the distance between the posterior rim of the hard palate and the anterior rim of the retroposed soft palate (Brauer, 165 ; Dorrance, 125). t is very unlikely that the length obtained in this way is all effective length. The term " pushback" would be better abandoned as well as the effort of " pushing" The lengthening operation should be regarded as a release operation. For the same reason lengthening procedures do not achieve the desired effect in cases of short palate without cleft, as Calnan (161) found in an X-ray study. We tried MiUard's lengthening operation in three cases of congenital short palate, with very disappointing results. No effective lengthening was achieved, although during operation this seemed to be the case. CNCLUSN t is difficult to draw definite conclusions from our findings. The results of this trial with Millard's island flap procedure indicate that a permanent effective lengthening of up to mm. can be achieved, provided that neuro-vascular bundles are treated with respect. t is not possible to compare the speech results with those obtained by authors using other methods. n some cases, especially in patients with scarred palates, they were not spectacular. Any improvement gained could then be attributed, possibly, to the speech therapy which was often given post-operatively, and the extra attention paid to these patients. n the other hand, some cases showed rapid and spectacular improvement, often without speech therapy. The need for the latter is largely determined by established speech faults secondary to the nasal escape. n the whole, we thought results were better than those previously obtained with simple pharyngeal flaps. t must be acknowledged that the method is not universally applicable. Lengthening is obviously of no avail in the paralysed palate, and probably not in the congenitally short palate. Also island flaps are not advisable in the badly scarred and collapsed hard palate, for technical reasons. t is possible that the lengthening procedure in which use is made of a pharyngeal flap to close the nasal defect is preferable, in some cases, as the pharynx

6 18 BRTSH JURNAL F PLASTC SURGERY is also narrowed by contraction of the donor defect. Whichever operation is used in treating nasality, it seems that in cases of repaired cleft palate a lengthening procedure should be incorporated when radiological examination shows that the palate is actively mobile but short. SUMMARY A number of patients with nasality in speech after a cleft palate repair were treated by secondary lengthening of the palate with MiUard's island flap method. The lengthening achieved was found to be permanent in the majority of cases, but the effective lengthening was limited to a maximum of approximately mm. The cause of this phenomenon is discussed. t is thought that lengthening procedures ought to be included in the treatment of nasality in patients with a repaired cleft. The importance of preoperative radiographs of these patients, as being the only accurate and universally recordable assessment of the condition, is stressed. The data on which this paper is based were obtained in the St Elisabeth Ziekenhuis, Tilburg, from patients treated in the department of plastic surgery. would like to thank Dr J. Hage, Head of this department, for his encouragement and advice. Also am grateful to Mr R. W. Hiles for his help with this paper. REFERENCES BJ6RK, L, and NYLEtq, B. (63). Acta chir. scan& 126, 434. BLACKFELD, H. M., WSLEY, J. Q., MLLER, E. R. and LAWSN, L,. (63). Plastic reconstr. Surg. 3, 542. BRATHWATE, F. (162). n " Modern Trends in Plastic Surgery ", ed. Gibson, T. London : Butterworth. BRAUER, R.. (65). Plastic reconstr. Surg. 36. CALNAN, J. (56). Br. 3. plast. Surg. 8, (6). Br. J. plast. Surg. 3, 23. CRtoN, T. D. (157). Plastic reconstr. Surg. 2o, 474. DRRAXCE, G. M. (125). Ann. Surg. 82, 2o8. DgaANCE, G. M. and BRANSFELD (43). Ann. Surg. x7,. Haarlem. De erven F. BohnN. V. GELDER, L. VAN (65). " Het zachte gehemelte bij de spraak ". HAGE, J. (66). Br. J. plast. Surg., 317. HAGERTY and HFMESTER, cited by van Gelder in " Het zachte gehemeke bij de spraak " H~G, C. A. (163). " ver pharyngoplastiek". Thesis, Utrecht. HYNES, W. (5). Br. J. plast. Surg. 3, 2. MLLARD, D. R. (162). Plastic reconstr. Surg (163). Surgery Gynec. bstet. x6, 27. RUDNG, R. (164). Plastic reconstr. Surg. 33, 32. SANVENERo-RoSSELL, G. (55)- Fortschr. Kiefer- und Gesichts-Chir., 65. SERCER, A. (135). Revue Chir. struct. 5, 5. SKG, T. (65). Br. J. plast. Surg. x8, 265. TRAUNER, R. (156). Br. J. plast. Surg. 8, 21. VEAU, V. (131). " Division Palatine ". Paris : Masson. WHLLS, J. (13o). J. Anat. 65, 2.