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Morbid anatomy and pathophysiology in the cleft palate. Dr.nuas hasab jafar. Anatomy and physiology. In approaching any surgical problem, one must have understanding of both normal and abnormal anatomy. the muscles form opposing slings that meet in the soft palate raphe.
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Morbid anatomy and pathophysiology in the cleft palate Dr.nuas hasab jafar
Anatomy and physiology In approaching any surgical problem, one must have understanding of both normal and abnormal anatomy
the muscles form opposing slings that meet in the soft palate raphe. The tensors and levators form the superior sling .palatoglossus and palatopharangeus form the inferior ones.
there are velar elevators and velar depressors The levator veli palatini is the primary elevator of the velum. It originates from the petrous portion of thetemporal bone , and inserts into the palatalaponeurosis Another elevator is the musculus uvulae Contraction of this muscle shortens the soft palate, basically bunching it up towards the back.
Depressors are the two palatoglossus muscles and the palatopharyngeus muscles . The palatoglossus originates from the palatal aponeurosis and inserts into the sides of the back of the tongue Contraction both elevates the tongue and depresses the velum.
And the last muscle is the tensor veli palatin They interdigitate with its partner on the opposite side in the midline of the soft palate this muscle doesn't elevate the velum at all. It's sole function is to open the Eustachian tube to allow the air pressure in the middle ear to equalize
In reality, the velum does not move like a hinged trap door but is only the anterior part of a complex velopharyngeal valve which functions as a circular sphincter
` *So here's a little physiology note: When at rest, the velum is depressed, allowing us to breath through our nose comfortably. So why do we need velar depressors? Well, the velum is elevated most of the time during speech (or singing), but when we want to make nasal sounds, like /m/ /n/ or nasal vowels, we've got to depress it very quickly. This is where the depressors come in, especially the palatoglossus. Allowing the elevators to simply relax would be too slow for comprehensible, flowing speech.
. Seal off the nasal from the oral cavities in order to isolate the oropharyngolaryngeal tract from atmospheric pressure during deglutition, producing a partial vacuum to facilitate compression of the food bolus by the tongue, cheeks, and pharynx, and therapy forcing it into the esophagus. It is very important for the Eustachian Tubes to open (when swallowing) so that pressure in the middle ear can be equalized with the pressure in the atmosphere Open the Eustachian tube
if the tensor Palatini muscles don't contractedThe Eustachian Tubes would not opentherefore the middle ear pressure cannot be equalized . With a cleft of the soft palate, the Levator Palatini from each side cannot interdigitate. As a result, the velum cannot elevate.
Difficulty in forming negative pressure as air leaks to and from the nasal cavities.Nasal regurgitation of milk, liquids, vomit, solids Effects on Feeding: Effects on Hearing Eustachian Tube dysfunction occurs in 95-100% of cases due to lack of interdigitation of the Tensor Palatini muscles. This results in chronic and recurrent otitis media and conductive hearing loss
Effects on Language Development Language may be delayed secondary to chronic otitis media and conductive hearing loss Difficulty building up positive pressure for high pressure sounds Effects on Speech and Resonance . . Hypernasality of vowels . Nasal air emission of consonants
closing of cleft palate should provide a mechanism for normal speech,hearing,dentalocclusion,swallowing,and separation of the oral and nasal cavities without interfering with facial bone grouth. :