A detailed history should include any diagnosed syndromes, history of cleft palate, history of recurrent ear infections, neurologic abnormalities, prior surgical intervention within the oral cavity or pharynx, episodes of nasal regurgitation during eating, and risk for obstructive sleep apnea.[3][24] 

The physical examination should focus on the oral and nasal cavities with attention to the soft palate height, mobility, and symmetry, tonsil size, tongue mobility and symmetry, oral competence, nasal mucosa, nasal turbinates, and septum. Inspection for any anatomical abnormalities such as a submucosal cleft palate, bifid uvula, zona pellucida, posterior palatal notching, or neuromuscular weakness and asymmetry is recommended. Mobility of the soft palate is inspected by asking the patient to maintain a sustained phonation of the vowel sounds “e” or “i”. The clinician should also perform an otoscopic exam to assess for otitis media with effusion or tympanic membrane retraction, as VPD can be associated with Eustachian tube dysfunction.[3][24]

The diagnosis of VPD is obtained through history, physical exam, assessment of speech production, imaging, and instrumental evaluation.   

1. Instrumental assessment provides a visual complement to perceptual speech analysis and is performed with either video-nasal endoscopy or multi-view videofluoroscopy by an interdisciplinary team of otolaryngologists, speech pathologists, and radiologists.
2. Perceptual speech analysis is the gold standard for VPD diagnosis and is performed by a speech-language pathologist (SLP). Patients are asked to produce plosive, fricative, and affricative sounds and assessed for any hypernasal speech, compensatory facial grimacing, or misarticulation. Common phrases include “pet the puppies” and “Kathy kissed the cat”. Patients can also be asked to count from 60 to 80. A dental mirror can be placed under the nostrils to visualize any nasal air emission through fogging of the mirror.[3][26]
   • Video-nasal endoscopy uses a pediatric flexible laryngoscope to directly visualize the nasal passages, nasopharynx, adenoids, and soft palate. Live images are displayed on a video monitor for the speech pathologist who is performing the phonemic evaluation on the patient. The velopharyngeal sphincter is assessed during sucking through a straw, as well as during the production of plosives, fricatives, and affricatives. The location of VP closure, size of VP gap, and mobility of VP structures can be visualized and used to guide surgical decision-making. Nasal endoscopy can also diagnose an occult cleft palate, seen as a midline groove on the nasal surface of the soft palate, as the cause for a patient’s VPD.[3]
   • Multiview videofluoroscopy is commonly used in young children who may not tolerate a video-nasal endoscopy. Barium is given trans-nasally to coat the soft palate, lateral, and posterior pharyngeal walls. Serial images oriented in the lateral, frontal, and basal views are taken to assess VP closure during phonemic evaluation by the speech pathologist. The VP closure pattern is then classified as either coronal, sagittal, or circular (symmetric). Coronal closure involves only the posterior pharyngeal wall and soft palate. Sagittal closure involves only the lateral pharyngeal walls. Circular closure involves all structures equally.[3][24]
3. Cephalometrics use serial X-rays from multiple views to study VP anatomic relationships during sustained speech. The anterior insertion of the levator veli palatini muscle into the soft palate is assessed, with more anterior insertion (seen in occult cleft palates) resulting in decreased soft tissue stretch and a VP gap during speech. Abnormalities in the cervical spine or skull base (platybasia) can contribute to nasopharyngeal disproportion. Cephalometrics is a quantifiable and reliable evaluation for treatment planning in children with velocardiofacial syndrome and isolated cleft palates.[3][27]
4. Magnetic Resonance Imaging (MRI) can be used to assess levator veli palatine muscle size, insertion into the soft palate, and orientation for cases of suspected submucosal or occult clefts.[28] Advantages include non-invasiveness, high-quality imaging, and lack of radiation exposure. However, it is expensive and often requires sedation for young children.[3]
5. Nasometry measures nasal emission and calculates a ratio between nasal and oral sound emissions (nasalance) using a sound separator placed between the nose and upper lip. The ratio is compared with normative values. Preoperative and postoperative nasalance can also be compared to determine surgery success. However, nasometry does not localize or quantify the VP gap. Large VP gaps can produce artificially low nasometric scores due to diminished high-pressure airflow.[3][24]

Treatment modalities for VPD include speech therapy, prosthetics, and surgery.[23]

1. Speech therapy is the mainstay of treatment for patients with mislearned articulation as well as those with poor compensatory mechanisms from VPD. In addition, patients who undergo surgical intervention should continue speech therapy to further enhance their speech outcomes.[24]
2. Oral prosthetics are custom-made by prosthodontists and anchored to the maxillary teeth to provide soft palate elevation. They are usually poorly tolerated by patients and often used as a temporary measure or for poor surgical candidates.[24] Prosthetics may also be utilized for patients with large palate fistulas after surgery, or as a temporary measure during a staged palate repair before completion of the second stage.
3. Surgery is the definitive treatment for anatomic causes of VPD with the goal of creating a functional seal between the nasal and oral cavities while avoiding airway obstruction. Operative repair usually takes place after age 3-4 years when patients are cooperative with instrumental diagnosis.[3] Surgical interventions include palate muscle repositioning, pharyngeal flap, sphincter pharyngoplasty, and posterior pharyngeal wall augmentation.[3][4]

• Palatal muscle repositioning maneuvers lengthen or readjust the orientation of palatal muscles. The Furlow double-opposing Z-plasty was originally used for primary cleft palate repair but has the added benefit of lengthening the palate by reorienting the levator veli palatini muscles in a transverse fashion.[29][30][31] It also has a lower risk of causing obstructive sleep apnea compared to the sphincter pharyngoplasty and pharyngeal flap.[32] Intravelar veloplasty involves re-aligning the levator veli palatini for cleft palate patients who did not undergo adequate muscle correction after their primary palate repair. The soft palate is opened along the midline with meticulous dissection and realignment of the abnormally inserted muscles.[4][20] Buccal myomucosal flaps raised from the inner aspect of the cheek have also allowed lengthening of the velum and retroposition of palate muscles.[33][34][35]
• Pharyngeal flap is ideal for the sagittal closure pattern and involves elevating a midline, superiorly-based flap of mucosa and superior pharyngeal constrictor muscle from the posterior pharyngeal wall and suturing it to the posterior soft palate.[36][37] The flap narrows the nasopharyngeal inlet and creates two lateral ports for nasal airflow, which can be sealed by the bilateral medial movement of the lateral pharyngeal walls. The width of the midline flap is determined based on the VP gap, location of VP closure, and mobility of the lateral pharyngeal walls on pre-operative nasal endoscopy.[38][39] The pharyngeal flap is also effective in some patients who have neurogenic causes of VPD such as those with 22q11 deletion syndrome with poor palate movement. Because it involves the creation of a permanent bridge of tissue between the palate and the posterior pharyngeal wall, it is not as physiologic as some of the other options for closure.
• Sphincter pharyngoplasty is ideal for the coronal closure pattern and involves elevating bilateral, superiorly-based flaps of palatopharyngeal mucosa and muscle. The flaps are rotated 90 degrees and the distal ends sutured to the contralateral posterior pharyngeal wall or to each other to create two horizontally overlapping arms.[40][41] This creates a smaller central port and a shorter transverse distance between the soft palate and posterior pharyngeal wall.[42]
• Posterior pharyngeal wall augmentation involves expanding the posterior pharyngeal wall with a graft or alloplastic material in order to decrease the distance between itself and the soft palate. Several materials have been described such as cartilage, fascia, acellular dermis, calcium hydroxylapatite, hyaluronic acid, fat, and silicone.[1][24][43] This surgical approach is best suited for mild VPD with a small central gap and can be used to complement pharyngoplasties where a small gap persists.[4][24]

• Faulty learning or dialectal influence. Children with no anatomical or neurological disorders may present with mild hypernasality secondary to mislearning or exaggerated regional dialects that emphases nasal characteristics.[10] Speech therapists should consider the native language and dialect of patients when performing perceptual speech analysis. In English, there is no distinction between nasal and oral vowel sounds, but distinctive nasal vowel sounds are common in many other languages including French, Portuguese, and Polish.

• Speech Sound Disorder (SSD) is a broad speech impediment where patients are unable to correctly form sounds of certain words. Children will commonly try and substitute, omit, or change the sounds of certain phonemes, resulting in unintelligible speech. Although this is commonly seen in young children, most kids self-correct their speech by 4 years old. SSD can be divided into articulation disorders which involve a deficit in the motor production of sound, and phonologic disorders which are characterized by trouble learning the different speech sounds and recognizing their distinct meanings.[44] Treatment is with speech therapy if the child does not self-correct before school-age.
• Childhood apraxia of speech (CAS) is a rare neurological condition that impedes a child’s ability to produce sound precisely and consistently. It involves a deficit in motor programming and planning and children are unable to express what they want to say into the necessary fine oral-motor movements. They have inconsistent errors in consonant and vowel production when repeating sentences.[45] These children need intensive and individualized treatment plans involving both an experienced speech-language pathologist as well as the child’s caregivers.

• Tonsillar hypertrophy can restrict VP closure and cause VPD. Symptoms can be improved after tonsillectomy. Evaluation and treatment of tonsillar hypertrophy should occur prior to any surgical interventions for VPD, as pharyngoplasty in the setting of tonsillar hypertrophy can further obstruct the airway.[24]

Due to the varying etiological causes for VPD, a thorough evaluation must be first be performed. Patients with hypernasal speech secondary to faulty learning, phonologic disorder, or language impairment without anatomic or neurological deficits should be treated with speech therapy.

Instrumentation can assist in surgical planning by determining the location of the VP closure, size of VP gap, mobility of VP structures, and pattern of VP closure (coronal, sagittal, or circular) as well as an underlying occult cleft palate.[3] In patients with neurological deficits or those who are poor surgical candidates, evaluation by a prosthodontist for oral prosthetics is recommended.[24]

VPD secondary to anatomic abnormality is most commonly caused by a cleft palate. Delayed primary cleft palate repair after 18 months is associated with a higher incidence of speech impairment and VPD.[46][47] However, the timing of VPD surgery has not been shown to affect long-term speech outcomes. Pamplona et al showed that earlier surgical treatment of VPD did not affect postoperative speech therapy.[48] Studies have shown that the success of VPD surgery and speech therapy is influenced mainly by the quality of speech therapy as opposed to the timing of the surgery.[49] Thus, older patients should not be denied surgery with the belief that they might not benefit due to their age. Neither speech therapy nor surgery alone can resolve the poor articulation from VPD and patients often require a combination of speech therapy and surgical interventions.[23][49]

Several studies note a successful reduction in hypernasality with pharyngoplasty up to 85%.[50][51] Failure after VPD surgery can present in 4% to 12% of patients who may require additional or revision surgery.[3] Several studies did not find gender, age, palatal defects, prior adenoidectomy, or IQ, to be predictors of postoperative speech outcomes.[52][53][54][55][56]

In a systematic review for patients with 22q11 microdeletion syndrome and VPD, there was no significant difference in speech outcome or morbidity between the different types of pharyngeal flaps.[4] Rates of failures from primary pharyngeal flap and sphincter pharyngoplasty have been equal, with both techniques being amenable to salvage through revision surgery.[55]

Complications from surgical intervention involve obstruction of nasal airflow, hyponasal speech, persistent hypernasal speech, and obstructive sleep apnea (OSA). The pharyngeal flap has been associated with lateral port stenosis, hyponasal voice secondary to over-obturation of the nasopharynx, and postoperative OSA in up to 20% of patients.[3][57] Native mucosa should be used to cover any exposed muscle during flap elevation to prevent tissue contraction and suboptimal obturation of the VP port. An increased risk of postoperative OSA has been found with sphincter pharyngoplasty requiring flap revision.[58]

Risks of posterior pharyngeal wall augmentation include migration or extrusion of injected material, foreign body reaction, and fat embolism.[59] Persistent VP gap and hypernasal speech can be treated with a combined surgical approach using both sphincter pharyngoplasty and Furlow palatoplasty. This combination approach requires significantly less surgical revision compared to pharyngeal flap or sphincter pharyngoplasty alone.[60]

Postoperatively, patients are admitted overnight and monitored for oxygen desaturations, snoring, hyponasal speech, and OSA. They are discharged once tolerating adequate oral intake. Patients with concern for sleep apnea should undergo formal polysomnography to evaluate for OSA and be considered for continuous positive airway pressure in the short term. Persistent sleep apnea, airflow obstruction, and hyponasal speech may require flap revision or takedown in the long term.[3][55] Speech therapy should continue after surgical repair to enhance speech outcomes and address poor compensatory behaviors used by patients prior to surgery.

Collaboration among the otolaryngologist, oral maxillary facial surgeon, plastic surgeon, speech-language pathologist, and the prosthodontist is essential for the diagnosis and treatment of velopharyngeal dysfunction. Close partnership with the cleft lip and palate team at hospitals is also beneficial due to the frequent association of VPD with cleft palate.[23]

The speech therapist is responsible for the perceptual analysis of speech production and interpretation of findings on nasal endoscopy and videofluoroscopy. A multidisciplinary review of endoscopic and radiographic images has been shown to increase the reliability of interpretations.[61]

Patient education on velopharyngeal dysfunction can be challenging due to the heterogeneous causes and need for multidisciplinary management. An early introduction to a speech-language pathologist is key for the diagnosis and alleviation of any inappropriate compensatory behaviors. Patients and their families should be counseled on the different methods of evaluation such as perceptual speech analysis, video nasal endoscopy, videofluoroscopy, and nasometry. Findings on testing and imaging should be shared and a discussion held regarding the best approach for treatment. Prior to any surgical intervention, patients and parents should be educated on the risks of surgery such as airway obstruction, sleep apnea, and need for additional surgical revisions.

Patients with velopharyngeal dysfunction should be managed by a multidisciplinary team of otolaryngologists, oral maxillary facial surgeons, plastic surgeons, neurologists, speech-language pathologists, prosthodontists, radiologists, primary care physicians, pediatricians, and geneticists. Early diagnosis and treatment of VPD are essential for long-term speech fluency and social function. Children with poor speech development and signs of VPD such as hypernasal speech and nasal regurgitation should be referred by their pediatricians to speech therapy for first-line treatment. A genetic workup should also be performed in collaboration with a geneticist.

Patients with associated neurological weakness should be evaluated by neurology. If anatomical abnormalities such as submucosal or occult cleft palate are diagnosed on instrumentation, a referral should be sent to an otolaryngologist or plastic surgeon specializing in velopharyngeal surgery. Speech therapy should continue even after surgical repair to enhance speech outcomes and address poor compensatory behaviors used by patients prior to surgery. Finally, patients may develop social anxiety and avoidance due to the intelligibility of their speech, especially in school and work settings. Formal peer support groups with parents and patients who share the diagnosis can aid patients in addressing their concerns.