STATE OF THE ART
Year : 2018 | Volume
: 5 | Issue : 2 | Page : 68--73
Intravelar veloplasty: A review
Rajshree Jayarajan1, Anantharajan Natarajan2, Ravindranathan Nagamuttu2,
1 Department of Plastic Surgery, University Hospitals of Leicester, United Kingdom
2 Maxillofacial, Facial Plastic and Reconstructive Surgery Centre, Pantai Jerudong Specialist Centre, Brunei Darussalam, Brunei
Dr. Ravindranathan Nagamuttu
Facial Plastic and Reconstructive Surgery Centre, Pantai Jerudong Medical Centre, Brunei Darussalam
Good speech is the ultimate aim in palate repair. Muscle function has to be optimum for the palate to be able to move to provide this goal. The fact that there has been a multitude of techniques of palatal repair indicates that none has been able to attain the intended objective. The method of intravelar veloplasty as a funtional technique has been the one that has gained wide acceptance all over the world. Use of magnification loops and microscope and better understanding of the cleft anatomy has helped to further refine the technique. This review aims at evaluating the outcome of this technique and its various modifications and complications. Literature search was performed in PubMed, Embase and Lilacs Bireme using the terms 'intravelar veloplasty', 'cleft palate repair', and radical muscle dissection'. No restriction were placed with regards to date of publication or language. Abstracts of the articles were assessed and the selected articles were reviewed in full by the authors. There is a striking diversity in the extent of muscle dissection between cleft surgeons. The evidence from the studies available showed better speech outcomes and velopharyngeal competence with radical intravelar veloplasty with varying complication rates. Uniformity in defining the degree of dissection of muscle by using a classification and standardised methods of outcome measurements are to be used in future studies to provide high quality evidence to guide decisions.
|How to cite this article:|
Jayarajan R, Natarajan A, Nagamuttu R. Intravelar veloplasty: A review.J Cleft Lip Palate Craniofac Anomal 2018;5:68-73
|How to cite this URL:|
Jayarajan R, Natarajan A, Nagamuttu R. Intravelar veloplasty: A review. J Cleft Lip Palate Craniofac Anomal [serial online] 2018 [cited 2019 Jan 20 ];5:68-73
Available from: http://www.jclpca.org/text.asp?2018/5/2/68/237635
“To assess the success of a palatal repair, listen, not look, as speech says it all” (Dr. H S Adenwalla). In earlier days, the aim of a palate repair was no breakdown and no fistula. Today, the criterion of success is clear audible speech. If this goal has not been achieved, the cleft team must review the surgical technique.
The principal aim of palate repair being good speech, the most important part of surgery is establishing maximal muscle function. This is achieved by meticulous dissection of the muscles, most importantly levator veli palatini (LVP) from its abnormal insertion and recreating the normal muscle sling – intravelar veloplasty (IVV).
There is a great amount of variation between surgeons on the extent of dissection done and no consensus as to “how much” is optimal. Hence, a review regarding how this problem can be addressed based on available evidence is of utmost importance in clinical practice.
Palatogenesis is complete by day 60 postconception. After the primary palate formation, which contains the central alveolar arch, the maxillary palatal shelves start fusing from incisive foramen anteriorly to soft palate posteriorly. Genetic and environmental factors can disrupt the normal process during this period resulting in either complete, incomplete or submucous cleft of the palate.
Normal palate anatomy
Velum forms the posterior third of palate and plays an important role in velopharyngeal closure. This is achieved by proper structural and physiological function of the velum musculature. The muscles of the soft palate include tensor veli palatini, LVP, palatoglossus, palatopharyngeus, musculus uvulae, and superior constrictor. Except musculus uvulae, all the muscles have extrinsic origin or insertion.
Tensor veli palatini arises from the scaphoid fossa and descends anteromedially and takes a right-angle turn at the pterygoid hamulus. Part of its fibers are attached to the hamulus and the remaining fibers run horizontally forming a thin sheet of palatine aponeurosis which fuses with the opposite side occupying anterior 20% of the soft palate. LVP arises from the skull base at the junction of cartilaginous and bony part of the eustachian tube and descends anteromedially before entering the velum. It interdigitates with the fibers of palatoglossus and palatopharyngeus over the middle 50% of the velar length and fuses with the opposite side. On contraction, it pulls the velum upward and backward toward the posterior pharyngeal wall. Together with tensor veli palatini, it helps in opening the eustachian tube, thereby contributing to middle-ear function. Musculus uvulae are a linear muscle on the superior part of LVP. Together with levator, it forms the genu of the soft palate on contraction, thereby effectively closing the velopharyngeal port. Superior constrictor forms the lateral and posterior pharyngeal wall and unites in the midline raphe posteriorly. On contraction, it pulls the lateral and posterior pharyngeal wall medially and anteriorly. Passavant's ridge, a localized mucosal bulge in the posterior pharyngeal wall caused by the underlying musculature, is present in 19% of normal speakers and in 24% of speakers with velopharyngeal insufficiency (VPI). Its functional role is debatable as the location in relationship to the isthmus is variable. The soft palate on the oral surface has thick submucosa with prominent minor salivary gland and absent on the nasal surface. The anatomical difference should be kept in mind while separating the nasal layer from the velar muscle. Hard palate is covered by thick mucoperiosteum on both the nasal and oral surface.
Veau and Borel in 1931 described the abnormal muscular attachment in the cleft palate. In cleft, the velar muscles are displaced anterolaterally. The tensor tympani tendon inserts into the posterior border of hard palate laterally without forming well-defined palatine aponeurosis. Few fibers of LVP muscle insert into the tensor tendon. The longitudinal fibers of palatopharyngeus, musculus uvulae, and most fibers of LVP muscle form a bundle and insert along the cleft margin in the anterior half of the velum and posterior edge of the hard palate without forming a muscle sling. The rigid attachment of muscle bundle results in isometric contractions, thereby pulling the palatal halves to move laterally, forward, and upward (paradoxical movement). Studies in cleft cases have shown that LVP muscle is hypoplastic with more connective tissue and less contractile elements. This may account for possible VPI even after a good cleft palate repair in some cases.
In 1954, Calnan described the triad (bifid uvula, a zona pellucida, and a notch in the posterior border of hard palate) for the submucous cleft palate. Kuehn et al. using magnetic resonance imaging (MRI) scan showed the absence of LVP muscle fibers across the midline in the submucous cleft palate. Superior constrictor muscle as such is not affected in cleft palate and is separated from the cleft muscles by palatosalpingeal fascia.
Mechanism of speech and swallowing, even though different, requires adequate closure of velopharyngeal isthmus. This is achieved by synchronous movement of soft palate and pharynx but is impaired in cleft palate resulting in hypernasality, nasal emission, and nasal regurgitation of food particles. Complete velopharyngeal closure is essential for the production of high-pressure oral sounds. Proper levator repositioning during surgery is critical for its function in speech and swallowing. Videofluoroscopy and videoendoscopy and recently MRI are being used to assess the velopharyngeal movement.
The evidence so far
Randall et al. found that patients with longer palates preoperatively had better speech after palate repair than those with shorter palates. However, the alteration in anatomy in cleft, namely normal origin and abnormal insertion of the muscles need to be addressed if a good functional outcome is to be achieved. As stated by Furlow, “if the velum cannot rise, its length is immaterial.”
The first surgical closure of congenital cleft of palate was done by Le Monnier, a French dentist, in 1764 by cauterizing the edges of the soft palate and bring them together with sutures.
Correction of the abnormal muscle in palatoplasty was first described by Braithwaite,, and the term “IVV” was coined by Kriens. The concept of radical IVV was put forward by Cutting et al. and modified by Sommerlad.
Velopharyngeal closure involves contribution from other muscles also, such as palatopharyngeus, palatoglossus, and superior pharyngeal constrictor. This review is specifically on IVV and the various modifications of this technique.
The steps in IVV consist of primarily:
Freeing the abnormal muscle attachment from the posterior border of the hard palateSeparation of muscle from nasal and oral mucosa to a different extentRetropositioningCreating a muscle sling by suturing the muscles in the midline.
The extent to which the dissection and retropositioning are done varies considerably.
The classification of IVV proposed by Andrades et al. has five types and is very useful when discussing the magnitude of dissection due to the considerable variation among cleft surgeons.
Type 0: No muscle dissection or suturing of muscleType 1: No dissection, parallel suturing of muscleType II a: Partial dissection (release from posterior palatal shelf but minimal dissection from nasal and oral mucosa) creating inverted-U muscle slingType II b: Partial dissection (dissection from nasal mucosa but not oral mucosa) creating inverted-V muscle slingType III: Complete dissection creating a transverse muscle sling (radical IVV).
In a follow-up series by Trier and Dreyer  of more than 4 years of levator reconstruction with von Langenbeck palatoplasty, velopharyngeal competency has been reported to be present in 89% of patients. During IVV, separation of muscle is done from palatal shelf, nasal, and oral mucosa, but the description regarding the extent of separation is not given.
A prospective single institute study by Marsh et al. on a sample of 51 patients concluded that IVV has no beneficial effect on velopharyngeal competence or if present is only of small magnitude. A long-term follow-up  of more than 25 years from the same study showed similar outcomes in adult quality of life.
Following better descriptions of muscle dissection and implementing the same, the results of IVV improved considerably.
A prospective cohort study comparing Wardill–Kilner pushback technique with Kriens IVV by Hassan and Askar  showed better velopharyngeal competence and eustachian tube function in the IVV group but higher incidence of fistula.
Bosi et al. assessed the immediate and late postoperative complications and their association with fistulae and with hypernasality of 60 patients who underwent palatoplasty with IVV. Their method involved dissection from the nasal mucosa using scissors and Freer elevator and minimal separation from oral mucosa (Type IIb). They had 20% incidence of immediate (fever cough, bleeding, and vomiting) and 13.3% incidence of late complications (bleeding, cough, infection, and trauma) and 16.67% incidence of fistulae and hypernasality incidence of 18.6%. Statistical analysis showed a significant association (P < 0.05) between the incidence of complications (both immediate and late) and fistula formation but no such relationship between fistula and hypernasality. They have concluded that IVV is a safe technique efficient for speech.
An assessment of 47 patients who underwent IVV at a teaching hospital in Erbil from 2009 to 2014 by Malki and Mustafa showed major improvement in velopharyngeal closure. The results seemed to be worse with wide and complete clefts.
A systematic review comparing Furlow's technique and IVV by Timbang et al. found that there is an increased incidence of VPI in straight-line IVV group compared to Furlow's group, but the fistula rate difference was not statistically significant.
A modification of Kriens IVV with a wavy-line incision with the aim of lengthening the palate has been reported by Henkel et al. They have reported an average lengthening of 56% with improved speech outcome and no fistulas with this method.
Radical intravelar veloplasty
Sommerlad  has described certain variations from the radical dissection by Cutting et al. A mucoperiosteal flap elevation is avoided, and muscle approach is through cleft marginal incisions. Von Langenbeck lateral releasing incisions are made only if necessary. The procedure is done under the operating microscope, and knife is used instead of scissors for dissection. The mucous glands are left attached to the oral mucosa and central part of nasal mucosa. Nasal dissection is done after the nasal mucosa has been sutured in the midline as this provides the tension for sharp dissection and is carried down to the blue in the mucosa. During the backward dissection from the posterior border of the hard palate, the tensor tendon is divided medial to the pterygoid hamulus. Once retroposed, the levator muscle bundles on either side are brought together in the posterior half of the velum using nonabsorbable sutures including the tensor tendon.
During a 10-year follow-up, the requirement for secondary velopharyngeal surgery reduced from 10.2% to 4.9% to 4.6% by 1992. The rate of fistula repair is reported to have been 15%, considered to be due to attempts to avoid lateral releasing incisions.
A retrospective study by Lu et al. on the incidence of palatal fistula following IVV by Sommerlad technique showed no increase in fistula rate. They have concluded that palatal fistulas are likely to be associated with the severity of cleft and the expertise of the surgeon.
In a study on 175 patients who underwent palatoplasty according to Sommerlad technique by Becker and Hansson, the fistula rate was found to be low, and they attribute this to liberal use of lateral releasing incisions. The most common site of fistula was at the junction of the hard and soft palate, and no difference in frequency of fistula was seen between different types of clefts in their series.
The advantages of using operating microscope for palate surgery have been enumerated by Sommerlad  as he has been using the same for the purpose since 1991. For the surgeon and assistant, it ensures a comfortable position, reliable lighting, and variable magnification and for the other trainees and operating theater staffs a good view of the procedure on the video screen.
The retrospective cohort series by Andrades et al. reports significantly better speech outcomes with radical IVV (81.9%) when compared to palate repair without radical IVV (49.5%), with postoperative complication rates remaining the same. They also had a low rate of secondary surgery ratio for VPI in the radical group (6.7% compared to 29% in other group).
Comparison of speech, VPI, and complications in another retrospective series  between two protocols (Malek and Talmant) one of which includes IVV has again shown statistically significant improvement in speech (75% with IVV and 30% without IVV) and lower rate of VPI (15% as compared to 55% without IVV) with no added complications for IVV. Here, IVV was done according to Sommerlad.
Addition of an oral Z as in Furlow's technique to the radical IVV technique of Sommerlad has been an innovation by Nagy and Swenne. Assessment of speech and VPI in their series is not available yet.
Overlapping IVV with oral Z pasty as a new technique is mentioned by Nguyen et al. This technique described as Woo palatoplasty by Albert S Woo for both primary and secondary palate surgery  involves overlapping the levators upon each other to create a taut reconstruction. In their study comparing non-IVV, Kriens IVV, radical IVV, and overlapping IVV, at 3 years, statistically significant improvement in velopharyngeal function was found in patients who underwent overlapping IVV compared to all the other groups, with none of the patients requiring secondary surgery. The fistula rates were 6.5% in non-IVV, 1.9% in Kriens IVV, 6.5% in radical IVV, and 3.8% in overlapping IVV. This study also like Marsh et al. has found no significant difference between non-IVV and Kriens IVV, probably indicating that it is the extent of dissection of the levator muscle that determines the outcome.
It is interesting to note that the use of operating microscope for palate repair, particularly dissection of LVP from the oral and nasal mucosa, has been described by Fujino  as early as 1977. He also mentions the technique of overlapping the muscle.
Role in re-repair of palate with intravelar veloplasty for velopharyngeal insufficiency
Palate re-repair with radical IVV (radical secondary IVV) as a method of correcting VPI was introduced by Sommerlad,, and he recommended it as the first-line treatment for VPI where primary palate repair has been done with little or no levator dissection and retrodisplacement. Statistically significant improvement in nasal escape and nasal resonance, velar closure, rate of velar movement, and extensibility was noted during postoperative assessment. A further consecutive series was reported later by Sommerlad et al. in which 84% of patients had previously undergone some degree of muscle correction in the primary repair. The indication for this procedure in patients with confirmed VPI was evidence of anterior insertion of LVP during intraoral examination, videofluoroscopy, or nasoendoscopy. A pharyngoplasty has been avoided in 88.2% of patients with this procedure.
A comparative study of IVV and pharyngeal flap for VPI by Barbosa et al. has shown pharyngeal flap to be more efficient in reducing hypernasality and attaining adequate velopharyngeal closure than IVV. The indication for IVV has been taken as anterior insertion of palate muscles and the presence of small velopharyngeal gap and good mobility of soft palate. Muscle retroposition was done according to Braithwaite in their series.
A retrospective cohort study series of 183 patients on palate re-repair with radical IVV for VPI by Elsherbiny et al. from 2000 to 2015 has demonstrated significant improvement in articulation, nasality, and nasal emission – 66.7% achieved normal or borderline normal speech and 24.3% showed improvement in speech. In their series, more than half of the cases which initially had radical IVV by the same surgeon also showed improvement with re-repair. They have recommended dissection and retropositioning of levator as a first-line procedure in cases of VPI even if the primary operation involved muscle dissection.
Extensive dissection of the muscle from oral and nasal mucosa leaves behind dead space with a potential risk for hematoma (stab incisions are made intentionally in the nasal mucosa by Sommerlad to avoid hematoma), and more the dissection, more the chances of scaring. Logically thinking, scar tissue would tether the muscle down and impair further movement – resulting in a paradoxical effect. However, studies have somehow shown that speech and VPC improve with more extensive muscle dissection.
We perform a radical dissection of the levator under 3.5-loupe magnification. Lateral releasing incisions are always used. The muscle is separated from the oral mucosa. After closure of the nasal layer, dissection of the muscle from the nasal mucosa is carried out down to “blue” in the mucosa. Slow and careful dissection is carried out at this stage, staying away from the blue itself to avoid fistulas. The pterygoid hamulus is fractured routinely. A transverse muscle sling is reconstructed using three sutures of nonabsorbable synthetic monofilament polyamide. During oral layer closure, two stitches at the junction of hard and soft palate include the nasal layer also. Uvuloplasty is done meticulously. We have had very good speech results and not had any fistulas or suture-related complications postoperatively for the past 10 years. We perform a similar technique for palate redo for VPI if lack or inadequate palatal movement is found to be the factor contributing to VPI during assessment. If palatal movement is adequate, we would do a pharyngoplasty, most often Orticochea.
The results of the studies available are in favor of a radical dissection and retroposition of the muscle in terms of speech and VPC. The reports show an increased incidence of fistulas as the amplitude of the muscle dissection increases. Complications appear to vary depending on experience of the surgeon and extent of muscle dissection and utilization or not of lateral releasing incisions. Functional outcome comparison is arduous as there is no international standardized scale. Well-designed multicenter randomized prospective studies with long-term follow-up using internationally standardized scales of outcome assessment are required to provide high-level evidence to govern our decisions on optimal surgical technique.
Palatal movement alone does not guarantee good speech. There are other factors involved such as length of palate, functioning of pharyngeal muscles, timing of surgery, and central nervous system function. Hence, quality of palatal muscle or extent of muscle dissection and muscle repair alone cannot be held responsible for suboptimal speech. As Adenwalla and Narayanan  have stated - there is no absolute truth in surgery.
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Conflicts of interest
There are no conflicts of interest.
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