Equine Respiratory Surgery, Arytenoid Chondritis, Guttural Pouch Issues

Question 1

What is your diagnosis?

Answer 1

Progressive ethmoid hematoma

• Clinical signs:
  
  • Epistaxis (bilateral)
  • Seroanguineous nasal exudate
  • Stridor
• Cause: nasogastric tubing

Question 2

What is the suspected cause of ethmoid hematoma in equines?

Answer 2

nasal gastric tubing

Question 3

Which of these radiographs shows a progressive ethmoid hematoma in this horse?

Answer 3

The one that says “PEH” on it

The way I understand it, the letters “PEH” will not be present on the hematoma in normal radiographs

Question 4

What procedure is taking place here?

Answer 4

Trephination

Question 5

What is the main postoperative complication associated with surgical removal of ethmoid hematomas?

Answer 5

Hemorrhage

Question 6

What is the composition of an ethmoid hematoma when viewed on histopathology?

Answer 6

• Outer surface: respiratory epithelium
• Central: hemosiderin-filled macrophages

Question 7

T/F: Chemical ablation with formalin is an acceptable treatment for ethmoid hematomas

Answer 7

True

• Transendoscopic Chemical Ablation:
  
  • 4% formalin via biopsy channel of endoscope
  • Can be done on an outpatient basis
  • Repeat in 2-3 weeks

Question 8

Definitive diagnosis of progressive ethmoid hematoma in horses is made by:

• Endoscopic exam
• History and PE
• CT
• Histopathologic exam

Answer 8

Histopathologic exam​

Question 9

What is the prognosis for long term resolution of progressive ethmoid hematoma?

• Grave no matter what treatment is performed
• Good if treated with intralesional formalin
• Guarded to poor no matter what treatment is performed
• Good if treated with surgical excision and cryotherapy of the base

Answer 9

Guarded to poor no matter what treatment is performed​

Question 10

In what breed have there been no reports of progressive ethmoid hematoma?

• Warmblood
• Arabian
• Tennessee walking horse
• Standardbred

Answer 10

Standardbred​

Question 11

What causes the color variations of the progressive ethmoid hematoma when viewed through a video endoscope?

Answer 11

Type and distribution of hemoglobin pigments​

Question 12

What is the most common clinical sign observed in horses with progressive ethmoid hematoma?

Answer 12

Epistaxis

Question 13

Which survey radiographic view most consistently demonstrates the lesion associated with progressive ethmoid hematoma?

• Dorsoventral
• Oblique
• Lateral
• None of the above

Answer 13

Lateral

Question 14

Formalin (10%) treatment for progressive ethmoid hematoma in the horse is administered via what route?

Answer 14

intralesional injection

Question 15

To monitor for recurrence after treatment of a progressive ethmoid hematoma, repeat endoscopic exam should be performed at ________ intervals for ________.

• 2 weeks; 2 years
• 1 month; 1 year
• 3-6 months; 5 years
• 1 year; 10 years

Answer 15

To monitor for recurrence after treatment of a progressive ethmoid hematoma, repeat endoscopic exam should be performed at 3-6 month intervals for 5 years.

Question 16

What is the cause of primary sinusitis?

Answer 16

upper respiratory tract infection (URTI)

Question 17

What are the causes of secondary sinusitis?

Answer 17

• Dental disease
• Facial fractures
• Cysts
• Neoplasia

Question 18

What are the clinical signs associated with sinusitis?

Answer 18

• Nasal discharge: serosanguineous
• Coughing
• Facial deformity

Question 19

What is the surgical treatment for sinusitis?

Answer 19

Sinusotomy (trephination)

Question 20

Aftercare for sinusotomy involves:

Answer 20

• Antibiotics + NSAIDs
• Leave open and flush daily
• Prognosis is good/excellent

Question 21

What is this horse doing?

Answer 21

Cribbing

• Grasp object with incisors
• Contract ventral neck muscles
• Pull backward
• Consequences:
  
  • Maybe colic
  • Abnormal wear of incisors
  • Weight loss

Question 22

Identify this piece of equipment:

Answer 22

Cribbing Strap

When the horse swallows, this puts pressure on the larynx

Question 23

What is the Modified Forssel’s procedure?

Answer 23

Surgical treatment for cribbing

• Myectomy:
  
  • Removal of Sternothyrohyoideus and Omohyoideus mm.
• Neurectomy:
  
  • Removal of ventral branch of spinal accessory nerve (XI)

Question 24

The cricoarytenoideus dorsalis muscle is innervated by the __________ nerve

Answer 24

recurrent laryngeal nerve

Question 25

Unilateral or bilateral paralysis of the cricoarytenoid muscle results in a condition known as:

Answer 25

**Recurrent Laryngeal Hemiplegia ("Roaring")** ## Footnote *Caused by progressive neurogenic atrophy (distal axonopathy) of the recurrent laryngeal nerve (branch of vagus nerve)*

Question 26

What is the most common cause of upper respiratory noise in the horse?

Answer 26

**Recurrent Laryngeal Hemiplegia ("Roaring")**

Question 27

Horses with laryngeal hemiplegia (LH) typically present for:

Answer 27

**Noise & Exercise Intolerance**

Question 28

What is the **Slap Test**?

Answer 28

**Evaluates recurrent laryngeal nerve and portions of spinal cord** * *S**lap withers during endoscopy* * *Observe adduction of **_contra_**lateral arytenoid cartilage* * *Pathway: spinal cervical cord* → *medulla decussation* → *recurrent laryngeal nerve*

Question 29

What is the most common surgical treatment for recurrent laryngeal hemiplegia?

Answer 29

**Laryngoplasty (Tie-back)**

Question 30

"Asynchronous abduction, but full abduction could be achieved" describes a Grade ___ laryngeal hemiplegia

Answer 30

**Grade II**

Question 31

"Asymmetry at rest, some movement, but full abduction cannot be achieved" describes a Grade ___ laryngeal hemiplegia

Answer 31

**Grade III**

Question 32

"Asymmetry at rest and no movement of the arytenoid cartilage" describes a Grade ___ laryngeal hemiplegia

Answer 32

**Grade IV**

Question 33

What are some complications associated with laryngoplasty?

Answer 33

* **Prosthesis failure** * **Loss of abduction** * **Seroma** * **Cough** * **Dysphagia**

Question 34

What should be done if an animal is coughing following a tieback procedure?

Answer 34

**Remove the sutures and start over again**

Question 35

Identify this instrument:

Answer 35

**Roaring Bur**

Question 36

What is arytenoid chondritis?

Answer 36

**Inflammation and thickening of the arytenoid cartilage​**

Question 37

What is a partial arytenoidectomy?

Answer 37

**Removal of the arytenoid body and corniculate process** * *50% of racehorses return to racing* * *Significantly improved upper airway flow dynamics* * *Coughing may be noted after surgery* * *Preferred treatment for arytenoid chondritis*

Question 38

\_\_\_% of racehorses return to racing after a partial arytenoidectomy

Answer 38

**50%**

Question 39

When the **soft palate** is **dorsally displaced** over the epiglottis, it is appropriately termed:

Answer 39

**Dorsal Displacement of the Soft Palate (DDSP)**

Question 40

This image shows a treatment option for *what condition?*

Answer 40

**Dorsal Displacement of the Soft Palate (DDSP)** *The image shows a tongue tie*

Question 41

What is a **staphylectomy**?

Answer 41

**resection of the posterior part of the soft palate** *May be used for surgical treatment of DDSP*

Question 42

Identify this instrument:

Answer 42

**Bistoury** *a surgical knife with a long, narrow, straight or curved blade*

Question 43

What intrinsic laryngeal muscle provides arytenoid abduction by drawing the dorsomedial margins of the arytenoid cartilages together?

Answer 43

**the arytenoideus transversus muscle**

Question 44

Which intrinsic laryngeal muscle is not innervated by the recurrent laryngeal branch of the vagus nerve? * the cricoarytenoideus dorsalis * the arytenoideus transversus * the cricothyroideus * the thyroarytenoideus

Answer 44

**the cricothyroideus​**

Question 45

A remnant of the thyroglossal duct is thought to cause: * Dorsal epiglottic abscessation * Subepiglottic granulomas * Epiglottitis * Subepiglottic cysts

Answer 45

**Subepiglottic cysts​**

Question 46

Alone, which recommended treatment for RLN _does not_ improve upper airway noise or return the upper respiratory airflow mechanics to baseline values? * Laryngoplasty * Bilateral ventriculocordectomy * Unilateral laser vocal cordectomy * None of the above

Answer 46

**Unilateral laser vocal cordectomy​**

Question 47

Laryngoplasty failure can be corrected by: * Partial arytenoidectomy * Ventriculectomy * Bilateral ventriculocordectomy * Unilateral laser vocal cordectomy

Answer 47

**Partial arytenoidectomy​**

Question 48

Which upper airway disturbance is thought to be caused by a developmental abnormality of the fourth branchial arch? * A subepiglottic cyst * Axial deviation of the aryepiglottic folds * Epiglottic retroversion * Rostral displacement of the palatopharyngeal arch

Answer 48

**Rostral displacement of the palatopharyngeal arch​**

Question 49

Which nerve/muscle combination is used when performing a neuromuscular–pedicle graft to treat recurrent laryngeal neuropathy (RLN)? * Hypoglossal nerve/hyoepiglotticus muscle * First cervical nerve/omohyoideus muscle * External branch of the cranial laryngeal nerve/cricothyroideus muscle * External branch of the cranial laryngeal nerve/thyrohyoideus muscle

Answer 49

**First cervical nerve/omohyoideus muscle​** *The neuromuscular–pedicle graft technique entails creating a pedicle graft involving the first cervical nerve and the omohyoideus muscle and implanting the entire graft into the affected cricoarytenoideus dorsalis muscle.*

Question 50

Which of the following is not a complication of surgical correction of epiglottic entrapment? * Reentrapment * Dorsal displacement of the soft palate * Laceration of the epiglottis * Epiglottic retroversion

Answer 50

**Epiglottic retroversion​**

Question 51

Which of the following disorders results in distortion of the corniculate process of the arytenoid cartilage, causing decreased arytenoid cartilage abduction, axial displacement of the arytenoid cartilage, and rostral displacement of the palatopharyngeal arch? * Axial deviation of the aryepiglottic folds * Rostral displacement of the palatopharyngeal arch * Arytenoid chondritis * Dorsal epiglottic abscessation

Answer 51

**Arytenoid chondritis​**

Question 52

In a resting horse, what fraction of the total resistance to airflow is in the upper airway?

Answer 52

**2/3**

Question 53

Videoendoscopy with the patient at rest allows diagnosis of all the following upper respiratory disturbances except: * Arytenoid chondritis * Axial deviation of the aryepiglottic folds * Persistent dorsal displacement of the soft palate (DDSP) * Persistent epiglottic entrapment

Answer 53

**Axial deviation of the aryepiglottic folds​**

Question 54

The intrinsic musculature of the pharynx includes all of the following except the: * Tensor veli palatini * Levator veli palatini * Palatopharyngeus * Hyoepiglotticus

Answer 54

**Hyoepiglotticus​**

Question 55

Which of the following extrinsic muscles of the pharynx is innervated by the pharyngeal branch of the vagus nerve? * Genioglossus * Thyrohyoideus * Sternohyoideus * Sternothyroideus

Answer 55

**Thyrohyoideus​**

Question 56

Rostral pharyngeal collapse has been experimentally reproduced by transecting the tendon of the _________ muscle.

Answer 56

**tensor veli palatini**

Question 57

Staphylectomy, epiglottic augmentation, rostral palatoplasty, and sternohyoideus/sternothyroideus myectomy are all treatments for: * Rostral pharyngeal collapse * Nasopharyngeal cicatrix * Dorsal pharyngeal collapse * DDSP

Answer 57

**DDSP**

Question 58

Dysfunction of the ________ muscle causes collapse of the pharyngeal roof during dorsal pharyngeal collapse

Answer 58

**stylopharyngeus caudalis**

Question 59

Which of the following _is not_ an acceptable treatment for nasopharyngeal cicatrix? * Antiinflammatory medications * Transendoscopic laser transaction * Permanent tracheostomy * Partial arytenoidectomy

Answer 59

**partial arytenoidectomy**

Question 60

Which upper respiratory disturbance may predispose a horse to DDSP as a result of inflammation of the pharyngeal branch of the vagus nerve? * Pharyngeal lymphoid hyperplasia * Elongated soft palate * Subepiglottic cyst * Epiglottic hypoplasia

Answer 60

**Pharyngeal lymphoid hyperplasia​**

Question 61

What is the maximal length that should be removed from the soft palate during staphylectomy for correction of DDSP?

Answer 61

**5 mm**

Question 62

What is the most likely diagnosis in this horse?

Answer 62

**Guttural pouch tympany**

Question 63

Which approach to the guttural pouch is illustrated below?

Answer 63

**Hyovertebrotomy** *The problem with this approach is that there is no ventral drainage*

Question 64

Which approach to the guttural pouch is illustrated below?

Answer 64

**Viborg's Triangle** * *Borders:* * *Sternomandibular muscle* * *Linguofacial vein* * *Caudal border of vertical ramus of the mandible*

Question 65

Which approach to the guttural pouch is illustrated below?

Answer 65

**Modified Whitehouse**

Question 66

What are the causes of guttural pouch empyema?

Answer 66

* **Upper respiratory infection** * **Abscessation of the retropharyngeal LN** * **Fracture of stylohyoid bone**

Question 67

Is guttural pouch empyema usually unilateral or bilateral?

Answer 67

**Unilateral**

Question 68

What are the main clinical signs associated with guttural pouch mycosis?

Answer 68

**Epistaxis and Dysphagia**

Question 69

What structure in the guttural pouch is most commonly affected by mycosis?

Answer 69

**internal carotid artery**

Question 70

Which surgical approach to the guttural pouches does not provide ventral drainage? * Hyovertebrotomy * Whitehouse * Viborg's triangle * Modified Whitehouse

Answer 70

**Hyovertebrotomy​**

Question 71

Which surgical approach is best suited for treat­ing guttural pouch mycosis? * A low hyovertebrotomy * Viborg's triangle * Whitehouse * Modified Whitehouse

Answer 71

**Viborg's triangle​**

Question 72

What is the most common complication of gut­tural pouch surgery? * Blindness * Dysphagia * Facial nerve paralysis * Abnormal respiratory noise

Answer 72

**Blindness​**

Question 73

Mycotic lesions of the guttural pouch have a propensity for developing in the __________ artery

Answer 73

**internal carotid**

Question 74

Which organisms are most commonly grown from diphtheritic plaque in cases of guttural pouch mycosis? * *A fumigatus and Streptococcus equi* * *E. nidulans and Histoplasma capsulatum* * *E. nidulans and A. fumigatus* * *Candida albicans and Blastomyces dermatitis*

Answer 74

***E. nidulans and A. fumigatus***

Question 75

What is the most common presenting sign of guttural pouch mycosis? * Dysphagia * Bilateral epistaxis, especially after work * Facial nerve paralysis * Unilateral epistaxis at rest

Answer 75

**Unilateral epistaxis at rest**

Question 76

Which ancillary procedure is most effective in diagnosing guttural pouch mycosis? * Endoscopy * Radiography * Ultrasonography * Fluoroscopy

Answer 76

**Endoscopy​**

Question 77

What is the recommended therapy for guttural pouch mycosis? * Scraping the fungal plaque off the guttural pouch membrane * Irrigation with antifungal medication * Surgery * Systemic antifungal medication

Answer 77

**Surgery​**

Question 78

Which artery is most likely to cause retrograde blood flow to mycotic lesions in the external carotid and maxillary arteries? * Linguofacial * Major palatine * Infraorbital * External ophthalmic

Answer 78

**Major palatine​**

Question 79

Current surgical techniques for arterial occlusion in treating guttural pouch mycosis include: * Ligation * Balloon catheterization * Transarterial coil embolization * All of the above

Answer 79

**All of the above​**