Auer Ch 44 Pharynx

Front 1

Function of intrinsic nasopharyngeal muscles:

Back 1

support the pharynx by contraction which tenses and dilates the nasopharynx

Front 2

Function of extrinsic nasopharyngeal muscles:

Back 2

regulate soft palate position, to increase nasopharyngeal diameter and decrease nasopharyngeal compliance (make it stiffer) by moving the tongue, or hyoid or laryngeal structures

Front 3

What are the intrinsic nasophayngeal muscles:

Back 3

tensor veli palatini, levator veli palatini, palatinus, palatopharyngeus, and caudal stylopharyngeus

Front 4

Combined function of TVP, LVP, palatinus, and palatopharyngeus:

Back 4

soft palate position

Front 5

Composition of the soft palate from ventral to dorsal:

Back 5

oral mucosa, palatine aponeurosis, palatinus & palatopharyngeus muscles, and the nasopharyngeal mucosa

Front 6

What is the palatine aponeurosis?

Back 6

expanded tendon of the TVP

Front 7

What does the palatine aponeurosis attach to?

Back 7

caudal aspect of the hard palate

Front 8

Vascular supply to the soft palate:

Back 8

linguofacial trunk and maxillary artery

Front 9

TVP innervation:

Back 9

mandibular branch of the trigeminal nerve

Front 10

Origin & insertion of TVP:

Back 10

originates at the petrous temporal bone, pterygoid bone, and lateral lamina of the auditory tube, travels ventral and rostral to the hamulus of the pterygoid bone, and inserts on the caudal hard palate as the palatine aponeurosis

Front 11

Function of the TVP:

Back 11

tenses the rostral soft palate and depresses it ventrally during inspiration

Front 12

Origin and insertion of the palatinus:

Back 12

originates just caudal to the palatine aponeurosis, extends caudally to end at the caudal free border of the soft palate, but it sends muscle bundles laterally to form the pillars of the soft palate, uniting dorsally to form the palatopharyngeal arch

Front 13

Origin and insertion of the palatopharyngeus?

Back 13

orgininates just lateral to the palatinus and form a portion of the nasopharyngeal wall, before terminating on the dorsal edge of the thyroid cartilage and dorsally on midline

Front 14

Innervation of palatinus:

Back 14

pharyngeal branch of the vagus nerve

Front 15

Function of the palatinus:

Back 15

shorten the soft palate, depressing it ventrally toward the tongue

Front 16

Innervation of palatopharyngeus:

Back 16

pharyngeal branch of the vagus nerve

Front 17

Function of the palatopharyngeus:

Back 17

shorten the soft palate, depressing it ventrally toward the tongue

Front 18

Origin and insertion of LVP:

Back 18

from the petrous temporal bone to insert within the glandular layer of the dorsal soft palate

Front 19

Function of LVP:

Back 19

elevates the soft palate during swallowing

Front 20

Innervation of LVP:

Back 20

pharyngeal branch of the vagus nerve

Front 21

Origin and insertion of caudal stylopharyngeus:

Back 21

originates on the medial aspect of the middle third of the stylohyoid bone and travels ventral and rostral to insert on the dorsolateral wall of the pharynx

Front 22

Innervation of caudal stylopharyngeus:

Back 22

glossopharyngeal nerve (CN9)

Front 23

How do extrinisic nasopharyngeal muscles increase nasopharyngeal diameter?

Back 23

altering the size of the oropharynx or the position of the larynx, which results in stability of the soft palate during exercise

Front 24

What are the extrinsic nasopharyngeal muscles?

Back 24

geniohyoideus, thyrohyoideus, genioglossus, hyoglossus, styloglossus, hyoepiglotticus, sternohyoideus and sternothyroideus

Front 25

Origin and insertion of genioglossus:

Back 25

originates within the median plane of the tongue and inserts on the mandible caudal to the symphysis

Front 26

Function of genioglossus:

Back 26

protracts the tongue, pulling the basihyoid rostral

Front 27

Innervation of genioglossus:

Back 27

hypoglossal nerve (CN12)

Front 28

Origin and insertion of geniohyoideus:

Back 28

originates on the medial aspect of the mandible and inserts on the basihyoid

Front 29

Function of geniohyoideus:

Back 29

tongue is protracted and the hyoid apparatus is pulled rostral

Front 30

Innervation of geniohyoideus:

Back 30

hypoglossal nerve (CN12)

Front 31

Function of styloglossus:

Back 31

retracts the tongue

Front 32

Origin and insertion of styloglossus:

Back 32

originating on the lateral aspect of the stylohyoid bone and inserting on the tip of the tongue

Front 33

Innervation of styloglossus:

Back 33

hypoglossal nerve (CN12)

Front 34

Function of hyoglossus:

Back 34

retracts the tongue, depressing the base of the tongue

Front 35

Origin and insertion of hyoglossus:

Back 35

originates on the lingual process, stylohyoid and thyrohyoid bones and inserts on the dorsal aspect of the tongue

Front 36

Innervation of hyoglossus:

Back 36

hypoglossal nerve (CN12)

Front 37

Function of sternohyoideus and sternothyroideus:

Back 37

retract the hyoid and laryngeal apparatus caudally

Front 38

Origin and insertion of sternohyoideus:

Back 38

originates at the sternum, inserts on the basihyoid bone and lingual process

Front 39

Origin and insertion of sternothyroideus:

Back 39

originates at the sternum, inserts on the thyroid cartilage

Front 40

Innervation of sternohyoideus :

Back 40

branches of the first and second cervical nerves

Front 41

Origin and insertion of hyoepiglotticus:

Back 41

originates on the hyoid bone and inserts on the epiglottis

Front 42

Function of hyoepiglotticus:

Back 42

pulls the epiglottis ventrally, increasing the ventral dimension of the rima glottis

Front 43

Innervation of hyoepiglotticus:

Back 43

hypoglossal nerve (CN12)

Front 44

Location of thyrohyodeus:

Back 44

between the thyroid cartilage and the thyrohyoid bone

Front 45

Function of thyrohyoideus:

Back 45

moves the larynx rostral so the thyroid cartilage is more dorsal and rostral than the basihyoid

Front 46

Examples of anatomical nasopharyngeal disorders:

Back 46

nasopharyngeal cicatrix or masses

Front 47

Where does nasopharyngeal cicatrix predomindately occur?

Back 47

hot climates in horses on pasture

Front 48

Etiology of nasopharyngeal cicatrix:

Back 48

environmental allergen is though to be the instigator of inflammation that results in a web of scarring

Front 49

Management of nasopharyngeal cicatrix:

Back 49

removing the horse from pasture and administering topical and systemic anti-inflammatory medications. Laser transection of some of the scar tissue or permanent tracheostomy can be considered in more severe cases

Front 50

What is not indicated for the treatment of nasopharyngeal cicatrix?

Back 50

Partial arytenoidectomy is not indicated because heavy scarring in the region predisposes to decreasing the diameter of the rima glottis

Front 51

Surgical approaches to the nasopharynx:

Back 51

nasal endoscopy, pharyngotomy, orally, or laryngotomy

Front 52

Complications of pharyngotomy:

Back 52

damage to the hyoepiglotticus muscle or its innervation

Front 53

Describe pharyngotomy:

Back 53

skin incision is centered on midline between the rostral aspect of the thyroid cartilage and the basihyoid bone. The sternohyoideus is separated on midline and the loose fascia between the thyroid cartilage and basihyoid is incised. Deep to this fascia is the hyoepiglotticus, which is separated on midline. The oropharyngeal mucosa is incised. The basihyoid can be split longitudinally with an osteotome to improve visualization

Front 54

Closure of a pharyngotomy:

Back 54

simple continuous closure of the oropharyngeal mucosa with poliglecaprone, steel wire in the basihyoid, continuous closure of the sternohyoideus, and just the subcutaneous and skin over the basihyoid

Front 55

Functional disorders of the nasopharynx:

Back 55

rostral pharyngeal collapse, dorsal or lateral nasopharyngeal collapse, and dorsal displacement of the soft palate

Front 56

What is rostral pharyngeal collapse?

Back 56

fluttering of the rostral aspect of the soft palate

Front 57

What rostral pharyngeal collapse conditions exist?

Back 57

Rostral palatal instability is billowing of the rostral aspect of the soft palate during inspiration and is associated with minimal obstruction. Palatal instability is billowing of the entire soft palate, which does cause obstruction and may be a precursor condition to DDSP

Front 58

Medical therapy for rostral pharyngeal collapse:

Back 58

systemic and topical anti-inflammatory medications, and use of a dropped or figure 8 noseband to prevent airflow into the oropharynx

Front 59

Surgical management of rostral pharyngeal collapse:

Back 59

laser thermoplasty, injection of sclerosis agents, thermal palatoplasty, and tension palatoplasty.

Front 60

Describe thermal palatoplasty:

Back 60

oral approach under GA. A T shaped iron is heated and used to cauterize the ventral (oral) surface of the soft palate from the hard palate to beyond the palatoglossal arch

Front 61

Describe tension palatoplasty:

Back 61

9-12 cm elliptical incision on the ventral (oral) surface of the soft palate extending from just caudal to the hard palate, removing a portion of the mucosa and submucosa. The edges are apposed with poliglecaprone in an interrupted pattern

Front 62

What is maximum tension palatoplasty?

Back 62

repeating the tension palatoplasty procedure 4 weeks after the initial procedure to further increase tension of the soft palate

Front 63

When can training resume after tension palatoplasty?

Back 63

hand walked for 4 weeks before training resumes

Front 64

Causes of dorsal or lateral pharyngeal collapse:

Back 64

Inflammation or neuritis may cause these conditions or they can be secondary to GP disease, HYPP, botulism, or EPM

Front 65

Treatment of dorsal or lateral pharyngeal collapse:

Back 65

directed toward the underlying condition and controlling inflammation

Front 66

Causes of DDSP:

Back 66

in a small amount of cases can be caused by structural abnormalities such as palatal cysts, subepiglottic masses, and epiglottic entrapment. Most cases are cause by intrinsic muscular disfunction which results in increased compliance (less stiffness) of the soft palate

Front 67

What tends to confer stability to the soft palate during exercise?

Back 67

Dorsally positioned larynx and basihyoid bone

Front 68

What does dysphagia with DDSP indicate?

Back 68

more advanced deficit of the intrinsic muscles or innervation and traditional treatments directed toward correction of respiratory impairment caused by DDSP may worsen aspiration associated with dysphagia

Front 69

Experimental models of DDSP:

Back 69

Model 1 is blockade of the pharyngeal branch of the vagus nerve, but results in both airway and swallowing dysfunction at rest. Model 2 is the thyrohyoideus muscle model which showed that this muscle decreased the collapsibility of the nasopharynx during exercise. Model 3 is blockade of the hypoglossal nerve which determined at the function of this muscle had a stabilizing effect on the nasopharynx

Front 70

What phase of respiration does DDSP affect?

Back 70

expiratory

Front 71

What are the differences in diagnosis of DDSP by treadmill or over ground endoscopy?

Back 71

treadmill examination diagnoses DDSP more frequently than over ground endoscopy, presumably due to lack of exercise protocol and reluctance of trainers to work the horse at maximal intensity with over ground endoscopy

Front 72

How is DDSP diagnosed if neither over ground or treadmill exercise is possible?

Back 72

Resting endoscopy immediately following work

Front 73

What may be associated with but not pathopneumonic for DDSP?

Back 73

ulceration of the caudal edge of the soft palate and bruising of the dorsal nasopharyngeal wall

Front 74

Medical management of DDSP:

Back 74

systemic and topical anti-inflammatory medication, allowing immature or unfit horses to mature or become fit, using a figure 8 noseband, using a bit that secures the tongue or restricts caudal movement of the tongue, using a tongue tie, or using a throat support device (cornel collar.)

Front 75

Bit options for DDSP:

Back 75

W bit, a spoon bit or a serena song bit

Front 76

Efficacy of tongue tie in DDSP:

Back 76

shown to be effective in 53-61% of cases, but experimentally is not associated with a change in position of the hyoid or larynx

Front 77

What procedures have not shown to be beneficial in DDSP?

Back 77

Those that aim to stiffen the soft palate, tension palatoplasty, thermal palatoplasty, sclerosing agent injection, and staphlectomy alone are not recommened

Front 78

When is staphlectomy used?

Back 78

removal of palatal cysts or granulomas, performed with laser application through nasal endoscopy in the standing post-operative laryngeal tie forward patient

Front 79

Describe staphlectomy:

Back 79

dorsal recumbency, a laryngotomy is performed. The caudal free margin of the palate is grasped with allis tissue forceps and retracted caudally OR by nasal endoscopy with application of laser to caudal free margin

Front 80

How much of the caudal free margin of the soft palate can be resected with a staphlectomy?

Back 80

less than 1 cm wide and in depth because resection of more than .75cm may disrupt the seal between the oro- and nasopharynx

Front 81

When can training resume after staphlectomy?

Back 81

2-3 weeks

Front 82

Complications of staphlectomy:

Back 82

removal of too much tissue from the caudal margin allowing aspiration of feed material

Front 83

Surgical options for DDSP:

Back 83

standard myectomy, minimally invasive myectomy, and laryngeal tie forward

Front 84

What is standard myectomy?

Back 84

partial resection of the sternohyoideus and sternothyroideus

Front 85

Function of standard myectomy?

Back 85

reducing caudal retraction of the larynx

Front 86

Describe standard myectomy:

Back 86

standing or under GA. A 10 cm incision is made on ventral midline at the junction of the proximal and middle third of the neck. The sternohyiodeus and sternothyroideus muscles are undermined. The proximal and distal aspect of the undermined muscles are clamped with Rochester-calmart forceps then sharply transected to remove a 6-8 cm segment of both muscles

Front 87

When can training resume after standard myectomy?

Back 87

2 weeks when sutures are removed from the skin

Front 88

Complications of standard myectomy?

Back 88

incisional

Front 89

What is minimally invasive myectomy?

Back 89

Llewellyn procedure or a partial sternothyroideus myectomy and tenectomy

Front 90

Describe minimally invasive myectomy?

Back 90

performed under GA. An incision is made on ventral midline centered over the cricoid cartilage, and dissection continues to expose the ventral, caudolateral aspect of the thyroid cartilage. The tendon of insertion of the sternothyroideus is undermined and transected 1 cm caudal to its insertion on the thyroid cartilage, which avoids injury to the caudal laryngeal artery and the cricothyroid muscle. A 3 cm section of the muscle is removed.

Front 91

When does training resume after minimally invasive myectomy?

Back 91

In STB, training begins in 2-3 days but in TB training is not resumed for 2-3 weeks

Front 92

Success of the partial sternothyroideus myectomy and tenectomy?

Back 92

58-70%

Front 93

Function of laryngeal tie forward:

Back 93

mimic or replace the action of the thyrohyoideus muscles

Front 94

Describe laryngeal tie back:

Back 94

dorsal recumbency, a 10 cm skin incision is made from 1 cm caudal to the cricoid cartilage to 2 cm rostral to the caudal aspect of the basihyoid. Dissection exposes the ventral and lateral aspected of the thyroid cartilage and the basihyoid bone. 5 fiberwire suture is double passed through the lamina of the thyroid cartilage just ventral to the insertion of the sternothyroideus tendon. A wire passer is placed under the basilyhoid on 1 side of the lingual process from rostral to caudal. The suture ends are passed through the wire passer, with the dorsal suture ends on the ipsilateral side and the ventral suture ends on the contralateral side. Suture is repeated on the opposite side. The head is flexed and the suture is tied so that the thyroid cartilage is dorsal to and 0.1 to 1.5 cm rostral to the caudal border of the basihyoid bone. A sternothyroideus tenectomy is performed prior to closure of the fascia, SQ and skin

Front 95

How is post-operative success of laryngeal tie forward assessed?

Back 95

Endoscopically the epiglottis is more forward and dorsal and often does not contact the soft palate. Radiographically, the tip of the epiglottis and larynx are more forward and dorsal

Front 96

When does training resume after laryngeal tie forward?

Back 96

hand walked for 2 weeks and then training can resume

Front 97

Nasopharyngeal disorders in foals:

Back 97

choanal atresia, nasopharyngeal dysfunction, and cleft palate

Front 98

What is choanal atresia?

Back 98

congenital abnormality with failure of the bucconasal membrane to resorb. The bucconasal membrane separates the oro- and nasopharynx

Front 99

When should surgical repair of unilateral atresia be performed?

Back 99

delayed until the foal is a yearling because there is a larger nasal cavity. Larger nasal cavity decreases the likelihood of post-operative fibrosis, and reduced diameter or complete choanal closure

Front 100

Approaches to choanal atresia repair:

Back 100

standing, laser assisted endoscopic resection of the membrane, a nasal bone flap approach, or through a laryngotomy

Front 101

When is nasal bone flap approach selected for choanal atresia?

Back 101

cases of bilateral atresia or when the membrane is osseous

Front 102

When is laryngotomy approach chosen for choanal atresia repair?

Back 102

young foals

Front 103

How is laryngotomy choanal atresia performed?

Back 103

nasal endoscopic illumination of the membrane. Incision of the membrane is with uni- or bipolar laparoscopic forceps

Front 104

What causes foal nasopharyngeal dysfunction?

Back 104

immaturity of neonatal neuromuscular reflexes and defenses mechanisms that normal protect the larynx and pharynx

Front 105

Treatment of foal nasophayngeal dysfunction:

Back 105

generally resolved in 10 to 30 days, with supportive care during this period. A tracheostomy can be considered for severe airway obstruction and enteral feeding in cases of dysphagia and aspiration

Front 106

Palatoschisis:

Back 106

cleft palate, a congenital defect caused by interruption of embryonic closure of the soft (+/- hard) palate

Front 107

Options for small cleft palate defect:

Back 107

surgical repair

Front 108

When should small cleft palate defects be repaired?

Back 108

delayed until the foal is older and the nasal cavity is larger

Front 109

Options for larger cleft palate defects:

Back 109

repaired or euthanasia

Front 110

Approaches to cleft palate repair:

Back 110

transoral approach, laryngotomy, pharyngotomy, or mandibular symphysiotomy

Front 111

When is pharyngotomy used for cleft palate repair?

Back 111

caudal 1/3 of the soft palate

Front 112

When is mandibular symphysiotomy used for repair of cleft palate?

Back 112

with soft and hard palate defects

Front 113

Complications of cleft palate repair:

Back 113

dehiscence, osteomyelitis of the mandible, salivary fistulas, and incisional infections

Front 114

When is cleft palate dehiscence apparent?

Back 114

7 to 14 days

Front 115

function of caudal stylopharyngeus:

Back 115

tenses the roof of the nasopharynx, preventing collapse during inspiration

Front 116

Disadvantages of injection of sclerosis agents or laser thermoplasty:

Back 116

have not shown to biomechanically alter the soft palate

Front 117

Innervation of sternothyroideus:

Back 117

branches of the first and second cervical nerves

Front 118

Back 118

nasaopharyngeal cicatrix

Front 119

Back 119

Front 120

Back 120

Thermal palatoplasty

Front 121

Back 121

Lateral pharyngeal collapse

Front 122

Back 122

DDSP

Front 123

Back 123

Front 124

Back 124

Front 125

Back 125