Pharyngeal flap surgery
Encyclopedia
Pharyngeal flap surgery is a procedure to correct the airflow during speech. The procedure is common among
people with cleft palate and some types of dysarthria
.
flap surgery is the most commonly used operation to restore velopharyngeal competence (i.e., develop a functional seal between the nasal cavity and the oral cavity), and therefore correct hypernasality and nasal air escape (Ysunza et al., 2002). Posterior pharyngeal flaps can be based superiorly or inferiorly and the velum
can be split transversely or along the midline (Lideman-Boshki et al., 2005). Centrally positioned, superior based flaps continue to be the most popular pharyngeal flap choice, yet inferior based flaps are easier for the surgeon
to perform. Compared to superiorly based flaps, inferiorly based flaps are limited in regard to the size of velopharyngeal opening that can be covered (Peterson-Falzone et al., 2001).
Pharyngoplasties correcting hypernasal speech
can be traced back as far as the 19th century when Passavant first explored palatopexy in a 23-year-old female (Hall et al., 1991). In 1876, Schoenborn also attempted to reduce the amount of air entering the nasal cavity by developing the first true inferior based pharyngeal flap surgery, where a flap of tissue
was sutured into the velum and attached to the lower end of the posterior pharyngeal wall. Modifying his technique, Schoenborn published a superior based pharyngeal flap surgery in 1886, where the flap of tissue attached to the upper end of the posterior pharyngeal wall. In 1928, Rosenthal used an inferiorly based posterior pharyngeal flap in combination with a modified von Langenbeck palatoplasty in primary surgery for cleft palate repair. Taking a different approach, Padgett (1930) utilized a superiorly based flap for cleft palate patients whose primary surgical repair had been unsuccessful (Sloan, 2000). By the 1950s, posterior pharyngeal flap surgery became widely adopted in the correction of VPI (Peterson-Falzone et al., 2001).
In the 1970s, Hogan and Shprintzen advanced posterior pharyngeal flaps, leading to an increased success rate in the elimination of VPI. Hogan (1973) proposed a ‘lateral portal control’ flap to modulate the postoperative port size. In this flap, lateral ports exist on both sides of the pharyngeal flap to assist in drainage, nasal breathing, and nasal resonance. Using the pressure-flow studies of Warren and colleagues as a basis for lateral port size, Hogan placed a 4 mm diameter catheter
through the lateral ports on either side of the flap to tailor the port size to the perception of nasal resonance (Sloan, 2000). Consistent with Warren’s aerodynamic data, Hogan advocated that the velopharyngeal opening be no greater than 4 mm in diameter because a larger gap would most likely result in hypernasal speech (Peterson-Falzone et al., 2001).
In 1979, Shprintzen advocated ‘tailor-made’ flaps, with the width of the flap determined by the degree of preoperative lateral pharyngeal wall adduction. According to Shprintzen, the base of the pharyngeal flap should be positioned at the site with the greatest level of lateral pharyngeal wall movement. In addition, Shprintzen recommends that a narrower flap be used with pronounced lateral pharyngeal wall movement, while a wider flap should be used with limited lateral pharyngeal wall movement (Sloan, 2000) Use of a narrow flap in individuals with limited preoperative lateral pharyngeal wall movement has the potential to increase lateral pharyngeal wall movement postoperatively (Karling et al., 1999).
The patient’s pattern of VP closure is one aspect that is taken take into consideration by doctors in deciding whether pharyngeal flap surgery is the appropriate method of treatment (Armour et al., 2005). A variety of closure patterns have been found, and the pattern varies person to person. When planning pharyngeal flap surgery, it is imperative for the doctor to match the postoperative structure to the preoperative movements in order for an adequate seal to be achieved (Ysunza et al., 2002). Research has found that pharyngeal flap surgery has been most effective for those with a sagittal closure pattern (good lateral wall movement but poor velar movement (Armour et al., 2005).
Pharyngeal flap surgery is not recommended for everyone and alternative treatment methods are available. One alternative is the use of a prosthesis
. In some instances, a prosthesis is capable of stimulating pharyngeal wall movement, thus aiding in VP closure. Most often, prostheses have been recommended for use in young children (Mazaheri et al., 1994). Currently, no accurate method is available to determine whether a pharyngeal flap or an alternative method will have better results for eliminating velopharnygeal incompetence.
Pharyngeal flap surgery has been completed in both children and adults. When younger children undergo the surgery, fewer speech impairments tend to occur. A possible explanation is that the earlier the surgery, the less likely the child will have developed compensatory strategies to overcome the velopharyngeal incompetence (Armour et al., 2005). However, with thorough preoperative planning, pharyngeal flap surgery can be just as effective in eliminating VPI in adults as it is in children (Hall et al., 1991).
of pharyngeal flap surgery include airway obstruction
and sleep apnea
(Pena, 2000). Snoring
has also been noted as a possible negative outcome of the surgery (Sloan, 2000). As a result of flap surgery, the airway is compromised in several ways. Some of the issues associated with this compromise include: narrowing of the nasal and oral airway secondary to edema
, impeding of the nasopharynx
by the flap itself, anatomical changes in which the oropharynx
becomes smaller, and decreased respiratory drive following anesthesia
. There is also a correlation between the individuals who have this surgery and the presence of other craniofacial
and neurological conditions. These factors together may lead to the above complications (Pena, 2000).
Postoperative airway obstruction may range from mild stridor
events to severe blockage of the airway resulting in intubation
or tracheostomy. All patients should be closely monitored following surgery due to the possible damage to the newly repaired palate or even the risk of death. In the literature, airway obstruction following pharyngeal flap surgery using the Wardill-Kilner and von Langenbeck techniques are well documented. It has been concluded that individuals with Franceschetti syndrome or Pierre Robin sequence are at increased risk for developing airway obstruction following pharyngoplasty due to their shallow nasopharyngeal airway and inadequate maxillofacial growth at the time of the surgery. It is also believed that prolonged duration of the surgical procedure may be directly correlated with an increased incidence of airway obstruction. Age does not seem to influence the risk. Factors that increase the risk of airway obstruction include associated congenital anomalies and a history of airway problems (Anthony & Sloan, 2002).
Sleep apnea can be categorized as obstructive sleep apnea (OSA) or central sleep apnea. The potential health risks of OSA are severe and therefore even a small percentage of incidence
is considered significant. Obstructive sleep apnea symptoms must be carefully assessed following pharyngeal flap surgery (Ysunza). This condition was found to be more commonly linked to posterior pharyngeal flap surgery, however, pharyngeal flaps are considered to be more valuable in correcting velopharyngeal function than other treatment options, especially in severe cases of VPI (Sloan, 2000). It has also been reported that large tonsils have been found in a high percentage of OSA cases. Large tonsils may be shifted posteriorly, under the ports of the flap. In superiorly-based pharyngeal flaps, tonsils are a likely contributor to OSA. Surgical procedures such as uvulopalatopharyngoplasties and tonsillectomies may be required to resolve the OSA. Consequently, tonsillar tissue is an important area of pre-operative assessment (Ysunza et al., 1993).
Often, speech improvements are not obvious immediately following the surgery. Speech improvements are more prevalent after one year post surgery and usually continue for several years. The outcomes of pharyngeal flap surgery vary among each individual in regards to improvements in hyponasality, hypernasality, nasal turbulence, voice quality, articulation, and intelligibility (Tonz et al., 2002; Liedman-Boshki et al., 2005).
Patients who undergo pharyngeal flap surgery encounter the risk of never breathing through their nose again, which could create abnormal speech (i.e., denasal resonance) (Witt et al., 1998). It is estimated that around 20-30% of patients with clefts develop hypernasal speech after pharyngeal flap surgery (Heliovaara et al., 2003). The percentage reported for individuals developing hypernasal speech is debated by researchers. It is possible that hypernasality can be a side effect of pharyngeal flap surgery, however hyponasal speech occurs more frequently after a successful surgery (Liedman-Boshki et al., 2005).
It is also possible that pharyngeal flap surgery will be unsuccessful. Some patients may even require secondary surgery for velopharyngeal insufficiency. It is common that individuals who have to undergo a second surgery could develop secondary speech problems, more specifically compensatory articulation and resonance disorders. Problems occurring post secondary surgery are often more difficult to extinguish (Tonz et al., 2002).
As previously mentioned, one problem that may occur after surgery is hypernasality. This is caused when a narrow flap and inadequate lateral pharyngeal wall movement prohibit lateral port closure during phonation. There are several other reasons surgery may fail the first time, including a poorly designed flap such as one that is too narrow, postoperative scar
(contracture of the flap), or inappropriate patient selection. Also, the flap may be too wide and occlude the lateral ports. There are higher rates of surgical failure in children with a history of perinatal upper airway obstruction, such as those with Robin sequence (Witt et al., 1998).
The type of cleft, as well as the type of flap used (superiorly or inferiorly-based) does not seem to make a difference in postoperative speech outcomes. It has been reported that different types of flaps give different speech configurations, however the results showed equally good outcomes for postoperative speech, regardless of the type of flap used. Therefore, it is imperative that the surgeon selects the right type of flap for each individual (Liedman-Boshki et al., 2005).
Overall, speech should improve after pharyngeal flap surgery. It is important to remember that improvement is variable and individuals react differently to surgery. Changes in speech do not always occur immediately after surgery, but this does not mean improvements will not be made. Lastly, speech problems such as compensatory articulation strategies do not often extinguish on their own. A speech language pathologist is usually involved both before and after pharyngeal flap surgery to monitor and help improve speech difficulties.
adults who have had this surgery as a child, when the tonsils are remained intact, can suffer as an adult if tonsillitis occurs, as currently no standard procedure exists to allow tonsils to be removed at a later date if tonsillitis become recurrent.
people with cleft palate and some types of dysarthria
Dysarthria
Dysarthria is a motor speech disorder resulting from neurological injury of the motor component of the motor-speech system and is characterized by poor articulation of phonemes...
.
Pharyngeal flap procedures
Posterior pharyngealHuman pharynx
The human pharynx is the part of the throat situated immediately posterior to the mouth and nasal cavity, and anterior to the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx , the oropharynx , and the laryngopharynx...
flap surgery is the most commonly used operation to restore velopharyngeal competence (i.e., develop a functional seal between the nasal cavity and the oral cavity), and therefore correct hypernasality and nasal air escape (Ysunza et al., 2002). Posterior pharyngeal flaps can be based superiorly or inferiorly and the velum
Soft palate
The soft palate is the soft tissue constituting the back of the roof of the mouth. The soft palate is distinguished from the hard palate at the front of the mouth in that it does not contain bone....
can be split transversely or along the midline (Lideman-Boshki et al., 2005). Centrally positioned, superior based flaps continue to be the most popular pharyngeal flap choice, yet inferior based flaps are easier for the surgeon
Surgeon
In medicine, a surgeon is a specialist in surgery. Surgery is a broad category of invasive medical treatment that involves the cutting of a body, whether human or animal, for a specific reason such as the removal of diseased tissue or to repair a tear or breakage...
to perform. Compared to superiorly based flaps, inferiorly based flaps are limited in regard to the size of velopharyngeal opening that can be covered (Peterson-Falzone et al., 2001).
Pharyngoplasties correcting hypernasal speech
Hypernasal speech
Rhinolalia , aperta = open, is the medical term for hypernasal speech. The other terms are hyperrhinolalia and open nasality. Hypernasality is a disorder of nasal speech when the sound of the voice is different, an abnormal resonance...
can be traced back as far as the 19th century when Passavant first explored palatopexy in a 23-year-old female (Hall et al., 1991). In 1876, Schoenborn also attempted to reduce the amount of air entering the nasal cavity by developing the first true inferior based pharyngeal flap surgery, where a flap of tissue
Biological tissue
Tissue is a cellular organizational level intermediate between cells and a complete organism. A tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. These are called tissues because of their identical functioning...
was sutured into the velum and attached to the lower end of the posterior pharyngeal wall. Modifying his technique, Schoenborn published a superior based pharyngeal flap surgery in 1886, where the flap of tissue attached to the upper end of the posterior pharyngeal wall. In 1928, Rosenthal used an inferiorly based posterior pharyngeal flap in combination with a modified von Langenbeck palatoplasty in primary surgery for cleft palate repair. Taking a different approach, Padgett (1930) utilized a superiorly based flap for cleft palate patients whose primary surgical repair had been unsuccessful (Sloan, 2000). By the 1950s, posterior pharyngeal flap surgery became widely adopted in the correction of VPI (Peterson-Falzone et al., 2001).
In the 1970s, Hogan and Shprintzen advanced posterior pharyngeal flaps, leading to an increased success rate in the elimination of VPI. Hogan (1973) proposed a ‘lateral portal control’ flap to modulate the postoperative port size. In this flap, lateral ports exist on both sides of the pharyngeal flap to assist in drainage, nasal breathing, and nasal resonance. Using the pressure-flow studies of Warren and colleagues as a basis for lateral port size, Hogan placed a 4 mm diameter catheter
Catheter
In medicine, a catheter is a tube that can be inserted into a body cavity, duct, or vessel. Catheters thereby allow drainage, administration of fluids or gases, or access by surgical instruments. The process of inserting a catheter is catheterization...
through the lateral ports on either side of the flap to tailor the port size to the perception of nasal resonance (Sloan, 2000). Consistent with Warren’s aerodynamic data, Hogan advocated that the velopharyngeal opening be no greater than 4 mm in diameter because a larger gap would most likely result in hypernasal speech (Peterson-Falzone et al., 2001).
In 1979, Shprintzen advocated ‘tailor-made’ flaps, with the width of the flap determined by the degree of preoperative lateral pharyngeal wall adduction. According to Shprintzen, the base of the pharyngeal flap should be positioned at the site with the greatest level of lateral pharyngeal wall movement. In addition, Shprintzen recommends that a narrower flap be used with pronounced lateral pharyngeal wall movement, while a wider flap should be used with limited lateral pharyngeal wall movement (Sloan, 2000) Use of a narrow flap in individuals with limited preoperative lateral pharyngeal wall movement has the potential to increase lateral pharyngeal wall movement postoperatively (Karling et al., 1999).
Candidacy
Pharyngeal flap surgery may be recommended to resolve velopharyngeal incompetence after patients prove unable to achieve significant speech improvements through speech therapy alone. Other requirements to qualify for the surgery include a short and immobile or easily fatigued palate (Mazaheri et al., 1994).The patient’s pattern of VP closure is one aspect that is taken take into consideration by doctors in deciding whether pharyngeal flap surgery is the appropriate method of treatment (Armour et al., 2005). A variety of closure patterns have been found, and the pattern varies person to person. When planning pharyngeal flap surgery, it is imperative for the doctor to match the postoperative structure to the preoperative movements in order for an adequate seal to be achieved (Ysunza et al., 2002). Research has found that pharyngeal flap surgery has been most effective for those with a sagittal closure pattern (good lateral wall movement but poor velar movement (Armour et al., 2005).
Pharyngeal flap surgery is not recommended for everyone and alternative treatment methods are available. One alternative is the use of a prosthesis
Prosthesis
In medicine, a prosthesis, prosthetic, or prosthetic limb is an artificial device extension that replaces a missing body part. It is part of the field of biomechatronics, the science of using mechanical devices with human muscle, skeleton, and nervous systems to assist or enhance motor control...
. In some instances, a prosthesis is capable of stimulating pharyngeal wall movement, thus aiding in VP closure. Most often, prostheses have been recommended for use in young children (Mazaheri et al., 1994). Currently, no accurate method is available to determine whether a pharyngeal flap or an alternative method will have better results for eliminating velopharnygeal incompetence.
Pharyngeal flap surgery has been completed in both children and adults. When younger children undergo the surgery, fewer speech impairments tend to occur. A possible explanation is that the earlier the surgery, the less likely the child will have developed compensatory strategies to overcome the velopharyngeal incompetence (Armour et al., 2005). However, with thorough preoperative planning, pharyngeal flap surgery can be just as effective in eliminating VPI in adults as it is in children (Hall et al., 1991).
Complications
The most common complicationsComplication (medicine)
Complication, in medicine, is an unfavorable evolution of a disease, a health condition or a medical treatment. The disease can become worse in its severity or show a higher number of signs, symptoms or new pathological changes, become widespread throughout the body or affect other organ systems. A...
of pharyngeal flap surgery include airway obstruction
Airway obstruction
Airway obstruction is a respiratory problem caused by increased resistance in the bronchioles that reduces the amount of air inhaled in each breath and the oxygen that reaches the pulmonary arteries...
and sleep apnea
Sleep apnea
Sleep apnea is a sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing, during sleep. Each pause in breathing, called an apnea, can last from a few seconds to minutes, and may occur 5 to 30 times or more an hour. Similarly, each abnormally low...
(Pena, 2000). Snoring
Snoring
Snoring is the vibration of respiratory structures and the resulting sound, due to obstructed air movement during breathing while sleeping. In some cases the sound may be soft, but in other cases, it can be loud and unpleasant...
has also been noted as a possible negative outcome of the surgery (Sloan, 2000). As a result of flap surgery, the airway is compromised in several ways. Some of the issues associated with this compromise include: narrowing of the nasal and oral airway secondary to edema
Edema
Edema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
, impeding of the nasopharynx
Nasopharynx
The nasopharynx is the uppermost part of the pharynx. It extends from the base of the skull to the upper surface of the soft palate; it differs from the oral and laryngeal parts of the pharynx in that its cavity always remains patent .-Lateral:On its lateral wall is the pharyngeal ostium of the...
by the flap itself, anatomical changes in which the oropharynx
Oropharynx
The Oropharynx reaches from the Uvula to the level of the hyoid bone.It opens anteriorly, through the isthmus faucium, into the mouth, while in its lateral wall, between the two palatine arches, is the palatine tonsil....
becomes smaller, and decreased respiratory drive following anesthesia
Anesthesia
Anesthesia, or anaesthesia , traditionally meant the condition of having sensation blocked or temporarily taken away...
. There is also a correlation between the individuals who have this surgery and the presence of other craniofacial
Craniofacial
Craniofacial may be used to describe certain congenital malformations, injuries, surgeons who subspecialize in this area, multi-disciplinary medical-surgical teams that treat and do research on disorders affecting this region, and organizations with interest in...
and neurological conditions. These factors together may lead to the above complications (Pena, 2000).
Postoperative airway obstruction may range from mild stridor
Stridor
Stridor is a high pitched wheezing sound resulting from turbulent air flow in the upper airway. Stridor is a physical sign which is produced by narrow or obstructed airway path. It can be inspiratory, expiratory or biphasic . Inspiratory stridor is common...
events to severe blockage of the airway resulting in intubation
Intubation
Tracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic or rubber tube into the trachea to maintain an open airway or to serve as a conduit through which to administer certain drugs...
or tracheostomy. All patients should be closely monitored following surgery due to the possible damage to the newly repaired palate or even the risk of death. In the literature, airway obstruction following pharyngeal flap surgery using the Wardill-Kilner and von Langenbeck techniques are well documented. It has been concluded that individuals with Franceschetti syndrome or Pierre Robin sequence are at increased risk for developing airway obstruction following pharyngoplasty due to their shallow nasopharyngeal airway and inadequate maxillofacial growth at the time of the surgery. It is also believed that prolonged duration of the surgical procedure may be directly correlated with an increased incidence of airway obstruction. Age does not seem to influence the risk. Factors that increase the risk of airway obstruction include associated congenital anomalies and a history of airway problems (Anthony & Sloan, 2002).
Sleep apnea can be categorized as obstructive sleep apnea (OSA) or central sleep apnea. The potential health risks of OSA are severe and therefore even a small percentage of incidence
Incidence (epidemiology)
Incidence is a measure of the risk of developing some new condition within a specified period of time. Although sometimes loosely expressed simply as the number of new cases during some time period, it is better expressed as a proportion or a rate with a denominator.Incidence proportion is the...
is considered significant. Obstructive sleep apnea symptoms must be carefully assessed following pharyngeal flap surgery (Ysunza). This condition was found to be more commonly linked to posterior pharyngeal flap surgery, however, pharyngeal flaps are considered to be more valuable in correcting velopharyngeal function than other treatment options, especially in severe cases of VPI (Sloan, 2000). It has also been reported that large tonsils have been found in a high percentage of OSA cases. Large tonsils may be shifted posteriorly, under the ports of the flap. In superiorly-based pharyngeal flaps, tonsils are a likely contributor to OSA. Surgical procedures such as uvulopalatopharyngoplasties and tonsillectomies may be required to resolve the OSA. Consequently, tonsillar tissue is an important area of pre-operative assessment (Ysunza et al., 1993).
Outcomes
Pharyngeal flap surgery may be able to improve speech performance in children or adults with a cleft palate who have velopharyngeal insufficiency. In fact, there is a high success rate for improvement of speech following pharyngeal flap surgery. However, surgery does not guarantee perfect or 100% intelligible speech. In addition to speech improvements, pharyngeal flap surgery may help eliminate hypernasality, nasal turbulence, and facial grimacing (Tonz et al., 2002).Often, speech improvements are not obvious immediately following the surgery. Speech improvements are more prevalent after one year post surgery and usually continue for several years. The outcomes of pharyngeal flap surgery vary among each individual in regards to improvements in hyponasality, hypernasality, nasal turbulence, voice quality, articulation, and intelligibility (Tonz et al., 2002; Liedman-Boshki et al., 2005).
Patients who undergo pharyngeal flap surgery encounter the risk of never breathing through their nose again, which could create abnormal speech (i.e., denasal resonance) (Witt et al., 1998). It is estimated that around 20-30% of patients with clefts develop hypernasal speech after pharyngeal flap surgery (Heliovaara et al., 2003). The percentage reported for individuals developing hypernasal speech is debated by researchers. It is possible that hypernasality can be a side effect of pharyngeal flap surgery, however hyponasal speech occurs more frequently after a successful surgery (Liedman-Boshki et al., 2005).
It is also possible that pharyngeal flap surgery will be unsuccessful. Some patients may even require secondary surgery for velopharyngeal insufficiency. It is common that individuals who have to undergo a second surgery could develop secondary speech problems, more specifically compensatory articulation and resonance disorders. Problems occurring post secondary surgery are often more difficult to extinguish (Tonz et al., 2002).
As previously mentioned, one problem that may occur after surgery is hypernasality. This is caused when a narrow flap and inadequate lateral pharyngeal wall movement prohibit lateral port closure during phonation. There are several other reasons surgery may fail the first time, including a poorly designed flap such as one that is too narrow, postoperative scar
Scar
Scars are areas of fibrous tissue that replace normal skin after injury. A scar results from the biological process of wound repair in the skin and other tissues of the body. Thus, scarring is a natural part of the healing process. With the exception of very minor lesions, every wound results in...
(contracture of the flap), or inappropriate patient selection. Also, the flap may be too wide and occlude the lateral ports. There are higher rates of surgical failure in children with a history of perinatal upper airway obstruction, such as those with Robin sequence (Witt et al., 1998).
The type of cleft, as well as the type of flap used (superiorly or inferiorly-based) does not seem to make a difference in postoperative speech outcomes. It has been reported that different types of flaps give different speech configurations, however the results showed equally good outcomes for postoperative speech, regardless of the type of flap used. Therefore, it is imperative that the surgeon selects the right type of flap for each individual (Liedman-Boshki et al., 2005).
Overall, speech should improve after pharyngeal flap surgery. It is important to remember that improvement is variable and individuals react differently to surgery. Changes in speech do not always occur immediately after surgery, but this does not mean improvements will not be made. Lastly, speech problems such as compensatory articulation strategies do not often extinguish on their own. A speech language pathologist is usually involved both before and after pharyngeal flap surgery to monitor and help improve speech difficulties.
See also
- Augmentation pharyngoplastyAugmentation pharyngoplastyAugmentation pharyngoplasty is a kind of plastic surgery for the pharynx when the tissue at the back of the mouth is not able to close properly. It is typically used to correct speech problems in children with cleft palate. It may also be used to correct problems from a tonsillectomy or because...
adults who have had this surgery as a child, when the tonsils are remained intact, can suffer as an adult if tonsillitis occurs, as currently no standard procedure exists to allow tonsils to be removed at a later date if tonsillitis become recurrent.