Thursday, October 3, 2019
Cleft Lip and Palate and its Effect on Speech Essay Example for Free
Cleft Lip and Palate and its Effect on Speech Essay Introduction on Speech and Phonetics            Phonetics and phonology are concerned with speech – with the ways in which human produce and hear speech. Talking and listening to each other are so much part of normal life that they often seem unremarkable. Yet, as in any scientific field, the curious investigator finds rich complexity beneath the surface. Even the simplest of conversations – an exchange of short greetings, for example – presupposes that the speaker and hearer make sense to each other and understand each other. Their ability to communicate in this way depends in turn on proper bodily functioning (of brain, lungs, larynx, ears and so on), on recognizing each other’s pronunciation a bewildering jumble of unpronounceable and unintelligible noise only underlines the extent of our organization and control of talking and listening within particular social and linguistic conventions.            Once we make a decision to start with an examination of speech, we can come up to it on a range of steps. At one step, speech is an issue of anatomy and physiology where we can examine the organs of speech such as tongue and larynx and their role in the creation of speech. Taking another perspective, we can focus on the speech sounds produced by these organs – the units that we commonly try to identify by letters such as a ‘b-sound’ or an ‘m-sound’. But speech is transmitted as sound waves themselves. Taking yet another approach, the term ‘sounds’ is a prompt that speech is proposed to be heard or supposed that it is then probable to concentrate on the manner in which a listener understands and process a sound wave (Clark, Yallop, Fletcher, 2006).            Phonetics is the study of the sounds of natural language. The use of sounds in speech involves three distinct phases: 1) the production of sounds by the speaker, 2) the transmission of sounds between the speaker and the hearer, and 3) the reception of the sounds by the hearer. Each of these phases especially 1) and 3), which clearly involve the human brain, is an extremely complicated process, each needs to be understood if we wish to have full understanding of the workings of human speech, and each requires its own methods of study. The science of phonetics thus consists of three main branches, each devoted to the study of one of the phases of speech.            Articulatory phonetics is the study of the way in which speech sounds are produced or ‘articulated’ by the speaker. It includes a description of the organs of speech, such as the vocal cords, the tongue and the palate, and how they are used to produce sounds. The description of speech in articulatory terms has a long history, going back to ancient times, and is still considered the most useful type of description for language teaching purposes. Acoustic phonetics is the study of the transmission of speech sounds through the air in the form of air waves. Precise studies of the transmission stage of speech rely heavily on electronic equipment which has only been available since the 1930s and 1940s, but in the relatively short space of time since then great strides have been made in our understanding of the transmission of speech sounds. Acoustic phonetics is not as important in pronunciation teaching as articulatory phonetics, but it can be of valuable assistance in certain areas such as the description of vowel sounds or intonations, which are not easily described in articulatory terms. Auditory phonetics, finally, studies the processes in the ear, auditory nerve and brain which lead to the perception of sounds by the hearer (Hall, 2003). Organs of Speech            The first essential for the student of Phonetics is to have a clear idea of the structure and functions of the various parts of the organs of speech. The term organs of speech is used to refer to parts of the body in the larynx and the vocal tract that are involved in the production of speech. It is a misleading term in that it suggests that we have special physical organs for speaking. This is not so: all our so-called ‘organs of speech’ have primary biological functions relating to our respiratory system and the processing of food (Gussenhoven Jacobs, 1998).            The organs of speech are all bodily structure composed of a variety of tissue types (such as bone, cartilage and skin) which are specific to their biological (rather than linguistic) function. Bodily organs are generally grouped into systems which have particular functions in the life of the organism. These include the respiratory system, the digestive system, and the reproductive system and so on. While it can be argued that the organs of speech form a system, they do not contribute to life support in the same way as other systems, and they are generally not thought of as performing their primary biological function when they are used in speech production (Clark et al., 2006). Nature of Speech Defects            Speech is a motor act that requires little concentration once it is learned. The energy source for speech is air. The diaphragm is the primary muscle of respiration and air is inhaled and exhaled through the vocal tract, the diaphragm contracts and flattens; this enlarges the thoracic cavity by displacing the abdominal contents downward and expanding the thoracic volume. The external intercostals assist the diaphragm in increasing the size of the thoracic capacity. If these movements are not coordinated, the supply and control of air may be reduced. Lack of coordination occurs during inhalation when the abdominal muscles contract simultaneously with the diaphragm and push the abdominal contents upward. This upward movement decreases the size of the thoracic cavity, which reduced the amount of air available for the production of speech. Restriction of the air supply may lead to reduced loudness, illogical breath groups, limited pitch range, decreased intelligibility and increased expiratory effort. Respiration for speech should be effortless and coordinated with phonation and resonation. Adduction of the vocal folds in a stream of air produces phonation. During quiet respiration, the vocal folds are abducted to an intermediate position by the poster cricoarytenoid muscles. Changes in the vibration pattern may result in altered voice quality, pitch, and loudness and decreased speech intelligibility Communication is a closed loop system. When individuals speak, others hear them and respond to their speech. In addition, individuals hear themselves speak and monitor their speech production. If speech production does not match the specific intention, then speech os modified. When speakers have a speech disorder, they may compensate for the impaired speech production by changing their respiration, phonation, and articulation. If this compensation is carried out in an effortful way, the compensation may be counterproductive and may worsen the symptoms (Brin, Comella, Jankovic, 2004). Speech Assessments            Speech assessments proper are established from the age of 4 years and allow objective evaluation to take place over a long period.            The articulation of phonemes is routinely evaluated during sessions of repetition as well as free speech.            The speech-language pathologist (SLP) will also evaluate the child’s speech production and some of the aspects of phonology. The SLP will ask the child to say various syllables or words and evaluate the â€Å"correctness†of what the child says. The SLP is trained to listen and compare all aspects of speech to a criterion of correct production. The SLP will comment on the child’s voice quality. Does the child’s voice sound like a typical child’s should at that age? Is it too high-pitched, strained, or too nasal? The SLP will comment on fluency, or the relative ease with which the child talks. Does the child stutter or stammer? The SLP will also perform oral-motor exam. In this exam, the SLP asks the child to do some movements incorporating his tongue, lips, teeth, cheeks, soft palate, and jaw. These movements are checked to see if the child has any weakness or coordination problems with the muscles and structures of the mouth that would influence the child’s ability to produce the speech sounds correctly. The SLP will also do an articulation test. In this test the SLP asks the child to say a group of syllables or words that contain all the sounds of English. The SLP makes a judgment about how correctly the child produced the sound. Sometimes the SLP marks whether the error was an omission (the child did not say the sound at all), a substitution (the child substituted one sound for another; for example the child said â€Å"pish†instead of â€Å"fish†), or a distortion (the child said a sound that was not the correct speech sound and did not sound like another sound). The SLP will list which sounds were produced incorrectly and make suggestions for follow-up therapy (Easterbrooks Estes, 2007). Cleft Lip and Palate            It is the term applied to a fissure in the roof of the mouth (palate) and/or the lip which is present at birth. It is found in varying degrees of severity in about 1 in 700 children. Modern plastic surgery can greatly improve the appearance of the baby and often further cosmetic surgery later will not be necessary. The parent of the child who has cleft lip and/or palate will be given detailed advice specific to his case. In general the team of specialists involved are the pediatrician, plastic surgeon, dentist or orthodontic specialist, and speech therapist (Havard, 1990).            The deficiencies associated with cleft palate depend on the location of the defect in the palate. In the normal palate, the tensor veli palatine and levator palatine muscles within the soft palate insert into an aponeurosis at the midline raphe. In the cleft palate, the muscle fibers follow the medial margin of the cleft and insert into the medial cleft edges and the posterior edge of the lateral bony hard palate. Clefts involving the alveolus can disrupt normal dental development, eruption, and retention.            The subject of normal human facial growth is extremely complex and incompletely understood; and superimposing a cleft defect complicates an already complex process. Many children with clefts will develop collapse of the alveolar arches, midface retrusion, and resultant malocclusion as they approach their teenage years. The underlying cleft deformity itself, as well as the surgical procedures performed to correct the defect, has been implicated as possible contributing causes of these developments. Currently, controversy exists regarding the relationship between surgical procedures and maxillary growth in terms of the sequencing of the surgical procedures, the timing of the cleft repair; whether or not the cleft repair itself has an effect on maxillofacial growth, and the various surgical techniques of lip and palate repair. Of interest, it is common in nonsyndromic older children whose cleft is unrepaired to have relatively normal midfacial projection and occlusion (Bailey, Johnson, Newlands, 2006). The Effects on Speech and Resonance            Dental problems in children with cleft lip and palate or craniofacial syndromes can be quite complex. These problems frequently require dental specialists to coordinate treatment with other health care providers in order to properly manage the patient. The specialists involved usually include a pediatric dentist, an orthodontist, an oral maxillofacial surgeon, and a prosthodontist. Together, they monitor and treat problems of the developing dentition, occlusion, and facial growth of the cleft lip/palate patient. As dental professionals reconstruct the oral environment, the speech pathologist leads to a more holistic management of the structural and functional effects of dental and speech abnormalities (Kumme, 2000).            Speech may be difficult to understand and have a muffled nasal quality, the greatest difficulty being in the pronunciation of consonants. This type of inadequate closure leads to the diagnosis of ‘cleft-palate’ speech, even though the palate is anatomically closed. In some cases adenoid tissue helps to close the space, so its removal by surgery or its decrease at the time of adolescence leads to further deterioration of speech. There may be associated, non-specific neurological symptoms (Baird Gordon, 1983). Cleft Palate Repair            The reasons for cleft palate repair are improved feeding, speech development and protection of the Eustachian tube, and effect on the growth of the middle third of the face. Not enough attention was paid to the hearing in cleft palate patients and, in the earlier years, the speech was also not given important consideration. All the attention was focused on the growth of the middle third of the face but if one misses the hearing and the speech, the damage is irreversible. The timing of cleft palate repair has always been governed by geographical location. In the European Centers, the repair is delayed for considerably longer, even up to six to seven years. In the English speaking countries, the repair is done around one year of age, but why leave these repairs till so late as speech usually develops by seven months? Physiologically, it is better to repair the palate before speech starts developing, so that postoperative edema and scarring settles down, it is then better to operate in the cleft palate at four months. Traditionally, the treatment of cleft lip and palate was to repair the cleft lip and anterior palate (single layer closure) between six to 12 weeks of age and repair the palate at about 18 months (Desai, 1997).            Currently, the majority of surgeons around the world who treat many of these children prefer to operate around 3 months of age for physiological and technical reasons. A 0.25mm error in alignment in a 1-day-old- child will show noticeable 1 to 2mm malalignment by age 1 year. The cleft palate is repaired best at around age 12 months. This is a compromise. Earlier repair may be an advantage for speech, but it is a disadvantage to subsequent facial growth. Late repair has an opposite effect. It is subsequently easier today to correct an underdeveloped midface in the 10% to 20% of patients in whom it may occur, rather than trying to correct bad speech in nearly all patients so treated by late palate closure. Cleft lip and palate need no longer be devastating deformity that it was 30 years ago, if untreated by an experienced team (which needs to see at least 40 new patients a year), the child should be expected to have normal speech, a symmetrical lip with a fine scar, a nose close to normal in appearance, and a full set of well-fitting teeth. To achieve this requires good patient and parent cooperation. In most cases, further surgery will be required by age 5 years to improve the nose shape. The wearing of orthodontic braces is almost inevitable but should be limited to 1 session in early adolescence. With good psychosocial support and good parenting, such children should grow into normal well-adjusted adults. However, if the quality of the surgery is bad and repeated operations are carried out, the speech and hearing are ignored and the teeth are not treated, then a very different psychological outcome will be present. Unfortunately, this still occurs even in the most advanced countries, if children are treated by either inexperienced or inadequately trained people, or without the benefits of a team approach, or where the team does not have a big enough population load to maintain its expertise (Eder, 1995). Surgical Management of the Primary Deformity            Lip Adhesion            If the child presents with a very wide cleft lip and a palate, it may be advantageous to â€Å"help†the cleft to become narrower, thereby facilitating the surgical outcome of the cleft lip repair. Most commonly, presurgical orthopedic molding of the wide cleft palate and lip can be accomplished with a process called â€Å"taping.†In taping, a strip of hypoallergenic tape is applied with tension across the cleft and secured to the child’s cheeks. The tape is worn 24 hours a day and reapplied as needed. Taping causes molding of the bony tissues by applying gentle pressure onto the protruding bony portions of the maxilla. This simple technique can be extremely effective in reducing the width of the cleft in a nonsurgical manner. When taping a ineffective or not tolerated by the infant, a lip adhesion can be considered. The goal of a lip adhesion is to surgically convert a complete cleft lip into an incomplete cleft lip, allowing the definitive lip repair to be performed with less tension. The lip adhesion also orthopedically molds and improves the alignment of the underlying maxillary segments before definitive lip repair. Lip adhesion, if indicated, is the initial procedure and it is performed at 2 to 4 weeks of age. Definitive lip repair follows the adhesion at 4-6 months of age, which allows the scar to mature. The following criteria are used to determine if lip adhesion is needed (following failure of the taping technique): Wide, unilateral complete cleft lip and palate where closure with conventional lip repair might produce excessive tension on the incision Symmetric, wide bilateral complete cleft lip with a very protruding premaxilla Introduction of symmetry to an asymmetric bilateral cleft lip A disadvantage of lip adhesion is the introduction of scar tissue, which can occasionally interfere with the definitive lip repair; although not usually a major concern, this has prompted some surgeons to limit its use. Cleft Lip Repair If no medical contraindications exist, and a lip adhesion has not been performed previously, definite lip repair is accomplished at 8 to 12 weeks of age. In the United States most surgeons follow the â€Å"rule of tens†: lip repair is performed when the infant is at least 10 weeks old, weighs 10 pounds, and has hemoglobin of 10 g. Cleft Palate Restoration Historically, the exact timing of surgical closure of the cleft palate has been controversial. The desire to facilitate velopharyngeal competence for adequate speech favors relatively early closure of the palate, whereas the possible negative influence on maxillofacial growth and occlusion favors relatively late closure. Anatomic factors to consider when evaluating the palate include the extent and width of the cleft (between both the alveolar ridge and palatal shelves); position of the maxillary segments; and, in the bilateral cleft, the size, position, and degree of protrusion of the premaxilla and prolabium. In both unilateral and bilateral complete cleft palate, collapse of the lateral maxillary segment can occur following the lip repair. In some cases, preoperative orthopedics can be used to realign the maxillary segments in a more normal position before the palate is repaired. In bilateral cleft, presurgical orthopedic treatment consists of molding the nasoalveolar process with progressively modified splints, and achieving lengthening of the deficient and short columella tissue, leading to an improved nasal appearance with a single stage procedure. Other groups favor techniques that allow for intranasal correction of the deformity and malposition during the lip repair. Although insufficient space exist to describe all the commonly used techniques, the principles of bilateral lip repair are common among them, including creation of the philtrum from the prolabium and midline tubercle from the lateral vermilion. A symmetric, bilateral complete cleft lip and palate with an adequate and moderately protruding prolabium and premaxilla are used as an example. Asymmetric, bilateral cleft lips and those with a rotated premaxilla can be treated with a one or two-stage closure (using the lip adhesion as the first stage). For children with an extremely protruding premaxilla, presurgical orthopedics may be required before definitive lip repair to move the premaxilla posteriorly, either surgically or via molding with appliances or tape (Bailey et al., 2006). Clinical Alert            Daily use of folic acid before conception decreases the risk for isolated (not associated with another genetic or congenital malformation) cleft lip or palate by up to 25%. Women of childbearing age should be encouraged to take a daily multivitamin containing folic acid until menopause or until they’re no longer fertile (Kumme, 2000).            Use of a contoured speech bulb attached to the posterior of a denture to occlude the nasopharynx helps the child develop intelligible speech when a wide horseshoe defect makes surgery impossible. Special nipples and other feeding devices are available to improve feeding patterns and promote nutrition in infants with a cleft lip or palate (Eder, 1995). Conclusion            There is no comparable series of routine cleft lip repair in newborn within 48 hours over a long period using the same technique; it is extremely difficult to fulfill such requirements as the temptation to alter the technique or timing is so great.            Every now and then, ideas about the treatment and techniques are reported in the literature or at conferences. There was considerable opposition to, and criticism of, our work at every level, nationally as well as internationally.            If one contemplates surgery in the newborn, then a proper team should be assembled. A surgeon should only undertake such a project if he feels it will help the child, not to impress other surgeons. A time will come when there will be fewer surgeons undertaking the treatment of these children in specialized centers.            It is a safe procedure in the hands of dedicated clinicians and surgeons. Pediatricians and the anesthesiologist should have a final say in the decision for surgery. It is possible to do a formal repair. The scar revision in unilateral cleft is comparable to any other series. In bilateral clefts the plan is to lengthen the columella, repair the orbicularis and narrow the philtrum at the same time at about four or five years of age. It may be worth looking at the technique of palate repair. One has to find a way to achieve repair early on in order to maintain hearing and speech results while achieving excellent maxillary alignment (Desai, 1997). References: Bailey, B. J., Johnson, J. T., Newlands, S. D. (2006). Head Neck Surgeryotolaryngology (4th ed. Vol. 1). Tokyo: Lippincott Williams Wilkins. Baird, H. W., Gordon, E. C. (1983). Neurological Evaluation of Infants and Children. London: Cambridge University Press. Brin, M. F., Comella, C. L., Jankovic, J. J. (2004). Dystonia: Etiology, Clinical Features, and Treatment. New York: Lippincott Williams Wilkins. Clark, J., Yallop, C., Fletcher, J. (2006). An Introduction to Phonetics and Phonology. Victoria, AU: Blackwell Publishing. Desai, S. N. (1997). Neonatal Surgery of the Cleft Lip and Palate. Hongkong: World Scientific. Easterbrooks, S. R., Estes, E. L. (2007). Helping Deaf and Hard of Hearing Students to Use Spoken Language. Thousand Oaks, CA: Sage Publications Inc. Eder, R. A. (1995). Craniofacial Anomalies: Psychological Perspectives. New York: Springer. Gussenhoven, C., Jacobs, H. (1998). Understanding Phonology. London: Oxford University Press US. Hall, C. (2003). Modern German Pronunciation: An Introduction for Speakers of English. New York USA: Manchester University Press. Havard, C. W. H. (1990). Blacks Medical Dictionary. Savage, Maryland: Rowman Littlefield. Kumme, A. W. (2000). Cleft Palate and Craniofacial Anomalies: The Effects on Speech and Resonance. San Diego, Canada: Thomson Delmar Learning.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.