Velopharyngeal Insufficiency

Velopharyngeal insufficiency is a disorder of structure that causes a failure of the velum (soft palate) to close against the posterior pharyngeal wall (back wall of the throat) during speech in order to close off the nose (nasal cavity) during oral speech production. Velopharyngeal insufficiency Anatomy The soft palate is commonly referred to as the Velum. Acts as a sphincteric valve to separate the oral and nasal cavities during speech and swallowing. Velopharynx (VP): Anteriorly: the velumLaterally: lateral pharyngeal wallsPosteriorly: posterior pharyngeal wall In speech production, the velopharynx is considered an articulator, as are the jaw, tongue, lips, pharynx, and larynx. In English, ALL phonemes are produced with oral airflow that requires VP closure to exclude nasopharyngeal airflow. Exception of /m/, /n/, and /ng/ which require an open nasopharyngeal valve and nasal airflow to produce these sounds. VELOPHARYNGEAL INSUFFICIENCY Functions of VP valve: Closure: Prevent the nasal escape of air and sound during production of oral sounds (most consonants and all vowels)Prevent nasal regurgitation during swallowing. Opening: Permit nasal consonant production /m/, /n/, and /ng/Permit nasal respiration. VP Closure ( VPC ): At the level of the VP isthmus, located along the inferior aspect of the adenoid bed.Elevation and retraction the of soft palate postero-superiorly.Simultaneous contraction of the lateral and posterior pharyngeal walls that move medially and anteriorly about 10 mm. Muscles of Velopharyngeal sphincter: Tensor veli palatiniLevator veli palatiniMusculus uvulaePalatoglossusPalatopharyngeus:Superior constrictor Tensor veli palatini: Tenses the soft palate and pulls it laterally.Opens the auditory tube during swallowing.Innervated by mandibular branch of the Trigeminal nerve. Levator veli palatini: Main muscle mass of the velum.LVP fibers interdigitate in the midline with the contralateral LVP to form the VP sling.Pulls the velum in a posterosuperior directionMajor elevator of the velumInnervated by Pharyngeal plexus. Palatoglossus: Lowers the velumElevates the tongue upward and backward to constrict the pillarsInnervated by Pharyngeal plexus. Palatopharyngeus: Narrows the velopharyngeal orifice by adducting the posterior pillars and constricting the pharyngeal isthmus.Raises the larynx.Lowers the pharynx.Innervated by Pharyngeal plexus. Musculus uvulae: Elevate the uvulaAdd bulk to the VP to occlude the VP port during speech and deglutition.Innervated by Pharyngeal plexus. Superior constrictor: Medial movement of the lateral aspects of the pharyngea walls.May function to draw the velum posteriorlyInnervated by Pharyngeal plexus. Passavant's ridge: Posterior wall movement seen in some individuals during speech or swallow, caused by a similar movement of the uppermost fibers of the superior constrictor and palatopharyngeus. Functions Levator veli palatini leads to elevation and posterior motion of the velumPalatoglossal + palatopharyngeus muscles - pull the palate downMusculus uvulae - adds bulk to the dorsal side of the velum.Uppermost fibers of the superior constrictor + palatopharyngeus - lateral wall motion. Pharyngeal plexus: Vagus nerve – MotorCranial part of Accessory nerve - MotorGlossopharyngeal nerve - SensorySuperior cervical sympathetic ganglion.Motor Supply to ALL the muscles of the pharynx (except stylopharyngeus, by the glossopharyngeal nerve).Motor Supply to ALL the muscles of the soft palate (except tensor veli palatini, by the mandibular division of the trigeminal nerve).Sensory innervation to oropharynx and hypopharynx. Pharyngeal plexus supplying VELOPHARYNGEAL area Velopharyngeal inadequacy: Failure of the sphincteric mechanism due to structural or neurological impairment or mechanical interference leading to loss of normal functions of the velopharyngeal valve. Etiologic categories: InsufficiencyIncompetenceMislearning Insufficiency: Structural defects that result in insufficient tissue to accomplish closure. Ex: Cleft palate Incompetence: Impairment of motor control secondary to neurologic dysfunction, such as paresis or paralysis. Ex: Post skull base surgery and tumors around the jugular foramen and vagus nerve. (CNS) impairment from brainstem stroke. Mislearning: Etiologic factors independent of structural defects or neuromotor pathology. Structural Abnormalities Cleft palate (most common)Congenital short palateOccult submucous cleft palateAbsent musculus uvulae.Hypertrophic tonsils by impeding palate closurePost tonsillectomy or other pharyngeal surgery causing tethering of velum by scarring Post adenoidectomy. Neuromuscular Abnormalities - Structurally intact VPMuscular dystrophiesMyasthenia gravisDown syndromeCVAPalatal paralysis An adenoidectomy can create or unmask VPD in any of these settings. Large adenoid can compensate for a short palate or a poorly mobile palate. With removal of the adenoidal tissue, the mechanism of compensation is eliminated. Velopharyngeal inadequacy has been reported to occur after 1 in 1500 adenoidectomies. The characteristic speech patterns of VPD : Increased transmission through the nasal cavityHypernasality due to excessive nasal resonance.Nasal emission due to turbulent airflow through the nasal cavityWeak pressure consonants: due to inability to generate sufficient oral pressure due to nasal leakNasal regurgitation. VELOPHARYNGEAL INSUFFICIENCY ASSESSMENT The diagnosis of VPI is typically ascertained by: Routine historical intakePhysical examinationCombination of perceptual speech, instrumental evaluation. Detailed history is elicited for any known syndrome or neurologic abnormalities.Inquiry about prior surgical intervention within the oral cavity or pharynx. Physical examination includes detailed inspection of the oral and nasal cavities.Attention to the velar height, palatine tonsil size, tongue, palatal and uvular appearance, nasal mucosa, turbinates and septum.Attention to the OP searching for signs of a submucosal cleft palate (bifid uvula, zona pellucida, posterior palatal notching)Physical examination always overlooks an occult cleft palate and thus other instrumental evaluation is needed to make this diagnosis. https://www.youtube.com/watch?v=BTZ7bpC5b68 Perceptual Speech Evaluation The gold standard of VPI evaluation.Listening to the spontaneous or prompted production of specific pressure phonemes while monitoring for misarticulations, hypernasal speech, nasal rustle, and facial grimacing.Facial grimacing is a compensatory action to narrow the external nares to decrease nasal air emission during non-nasal speech.Use of the dental mirror placed under the nares during vowel production, may also assist in determining the amount of visible nasal air emission as shown by fogging of the mirror. Speech Videofluoroscopy A small amount of barium is introduced through the nose to coat the velopharynx.Under fluoroscopy, the child repeats or reads a set of phonemespecific speech tasks.Limitations:RadiationCooperationDifficult to evaluate postsurgical changes. Speech Endoscopy Flexible nasopharyngoscope is introduced into the velopharynx.Most useful tool for evaluation.A series of words, phrases, and sentences are spoken while Endoscopy allows assessment of the static anatomy and visualization of the VP closure. Four primary closure patterns. These patterns are best understood in terms of the residual gap orientation on incomplete closureof the velopharynx. Coronal pattern - Coronally oriented gapMost common ( 55% )Major contribution to closure is from the palate (velum) Sagittal pattern - Sagittaly oriented gapLeast common ( 10-15% )Major contribution to closure is from the lateral walls. Circular patter Circular central gap10% to 20% of the populationMajor contribution to closure is from the velum and the lateral walls. Circular pattern with passavant’s ridge 15% to 20% of the populationMotion of the velum and lateral walls with Passavant’s ridgeKnowing where the “gap” is should allow the clinician to decide how best to obturate that gap. Four primary closure pattern of VPI Management: Speech therapy.Not appropriate for abnormal structure only (e.g., VPD with intact articulation after adenoidectomy or tumor resection)Provide compensatory strategies, if the structural abnormality cannot be corrected.Mild VPD.Post-op to learn to use the new structure. Prosthetic Management of Velopharyngeal Insufficiency Palatal lift pushes the palate up and back to contact the posterior pharyngeal wall, Not good for short palate Obturator places a round piece of acrylic into the velopharynx Surgical Management of Velopharyngeal Insufficiency1 Pharyngeal Flap for Velopharyngeal Insufficiency Indicated in case of good lateral wall motion and poor velar motion ( Sagittal or circular closure patterns)The most widely performed surgical procedure to improve VPI.Tissue from the posterior pharyngeal wall is attached to the soft palate, creating a midline subtotal obstruction of the oral and nasal cavities with 2 small lateral openings.Pharyngeal flaps can be based superiorly ( most common ) or inferiorly.Inferiorly based posterior wall flap was initially described.Modification to this procedure was done by using a superiorly based flap after founding that an inferiorly based flap tended to contract and tether the palate downward over time, worsening the patient's VPI. Pharyngeal Flap for Velopharyngeal Insufficiency The soft palate is incised in the sagittal midline from the uvula toward the junction of the soft and hard palate.The superiorly based pharyngeal flap is elevated off the prevertebral fascia.The flap is inset to the soft palate and sutured to the nasal side of the soft palate with interrupted sutures.The donor site is partially closed with 3-0 Vicryl sutures.The oral side of the soft palate is then closed with interrupted sutures. Outcome: 90% resolution of hypernasality.Failure to improve is related to inadequate flap width either by design or due to contracture.A flap that is too wide narrows the lateral ports and produces hyponasal speech.Postoperative airway obstruction is most likely to occur within the first 24 hours and resolved within 2 days in more than 90% of patients. Sphincter Pharyngoplasty for Velopharyngeal Insufficiency Patients with good velar elevation but poor lateral wall motion are good candidates for sphincter pharyngoplasty.Ideal for a coronal closure, and useful in the circular closure.Narrow the central velopharyngeal orifice and minimizing airflow through the nose during speech.It accomplishes this by rearranging palatopharyngeus myomucosal flaps raised from the posterior tonsillar pillars, which are transposed to the posterior pharyngeal wall and approximated on the midline.This procedure tightens the central orifice without creating lateral ports.Decrease risk of post-op airway obstruction. Sphincter Pharyngoplasty for Velopharyngeal Insufficiency Posterior Pharyngeal Wall Augmentation Indicated mainly for very small posterior midline gap.Persistent postadenoidectomy VPI is also an appropriate indication for this procedureA wide variety of implantable materials have been tried.Substances are typically placed within the retropharyngeal space just deep to the superior constrictor muscle but superficial to the pharyngobasilar fascia.Most commonly fat and calcium hydroxylapatite.Outcome data are scant. varying degrees of success have been reported. Rolled posterior pharyngeal wall: Raising a U-shaped posterior pharyngeal wall myomucosal flap to the tubercle of the atlas. The tip of the flap is connected by deep bites to the base of the flap. By securing the knots, the flap is rolled on itself, creating a soft tissue bulge or augmentation. Palatal Lengthening - Goals of this procedure are to lengthen the palate, occlude a small gap in the velopharyngeal port, and retrodisplace the palate in a more physiologically normal place. V-Y pushback procedure Furlow double-opposing Z-plasty palatoplasty https://www.youtube.com/watch?v=394nbrjejko Anatomy of Pharynx References 1. Shprintzen R, Marrinan E. Velopharyngeal insufficiency: diagnosis and management. Curr Opin Otolaryngol Head Neck Surg. 2009;17(4):302-307. doi:10.1097/MOO.0b013e32832cbd6b Pubmed

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