Chapter 43 & 44 - Nasal passages and sinuses Flashcards
What are strong indicators of palatal dysfunction?
Easy and prolonged displacement of the soft palate (SP).
How can dynamic displacement of the soft palate (DDSP) be induced during endoscopy?
- By transient nostrils occlusion
- inserting an endoscope into the cranial trachea, slowly withdrawing,
- flexing the head and neck.
What is the specificity and sensitivity of observing DDSP at rest?
Specificity is 85%, and sensitivity is 26%.
Apart from DDSP, what other abnormalities may be observed, as per postmortem studies in racehorses?
Prevalent lesions in the subepiglottic area.
What is the gold standard for diagnosing DDSP, and why?
Exercising endoscopy is the gold standard because DDSP is a dynamic event occurring during exercise.
What steps are taken during a resting endoscopic evaluation of the trachea, guttural pouch, and nasal passage?
Sedation, local anesthesia, and elevating the epiglottis with bronchoesophageal forceps.
What might indicate temporohyoid osteoarthropathy during endoscopy?
Enlargement of the stylohyoid bone and the temporohyoid joint within the dorsal guttural pouch.
What factors are simulated on the treadmill to induce exercise stress?
Head/neck flexion,
fatigue,
and incremental speed.
What is the primary diagnostic tool for exercise intolerance and respiratory noise?
Treadmill.
Why is uphill exercise considered appropriate, especially in jumping horses?
To simulate the conditions faced by jumping horses.
How can septal deviation be evaluated since it’s difficult with an endoscope?
Check with radiographs.
How is dynamic endoscopy categorized, and what are the major criteria for abnormal laryngeal function during exercise?
Categorized as A, B, C;
A is able to obtain and maintain full abduction of the arytenoid cartilages (AC) during exercise.
What are predisposing factors for inducing dynamic displacement of the soft palate (DDSP)?
Headgear, head/neck flexion, and pressure on the bit.
What cases exhibit** normal laryngeal** and pharyngeal function at rest but not during** exercise?**
1- Axial deviation of the aryepiglottic folds,
2- pharyngeal wall collapse,
3 - epiglottic retroversion.
How might epiglottic hypoplasia and falccidity contribute to predicting DDSP during exercise?
These conditions, along with soft palate ulceration, can help predict DDSP during exercise.
What percentage of racehorses with respiratory noise or exercise intolerance may have a false-negative diagnosis DDSP based on resting endoscopic findings?
A. 60%
B.30%
C. 85%.
C. 85%.
What is considered the gold standard for diagnosis of upper airway disease?
Overground endoscopy or dynamic endoscopy
Ventral concha sinus and rostral maxillary sinus
What additional diagnostic information can ultrasound provide regarding upper airway diseases?
It can provide structural and functional information about the location and extent of disease, corroborating endoscopic findings.
What enhances the diagnostic value of radiography for equine skulls?
Large gas-filled structures such as the guttural pouch, nasal cavity, larynx, pharynx, and paranasal sinus.
Middle (MM) and common (CM)nasal meatuses of the right nasal cavity in thenormal horse. The middle meatus is defined asthe space between the dorsal and ventralconchae, and the common meatus is the spacebetween the conchae and the nasal septum –note the ‘y’-shape created by the dorsal concha(DC) dorsally, the ventral concha (VC) ventrolaterallyand the nasal septum (NS) medially.The lateral part of the middle meatus is usuallytoo small to pass an endoscope into.
What is the major criteria for diagnosing sinusitis in radiographs?
Identification of a fluid line, but multiple fluid lines require careful distinction of affected sinuses.
What are some other special views mentioned for equine skull radiography?
Intraoral,
right to left lateral,
left to right lateral,
dorsal obliques,
lateral obliques,
and contrast studies.
Which sinuses are more predisposed to disease due to direct communication with the nasal cavity and dental alveoli?
The maxillary sinuses.
What variation in the bony labyrinth of the sphenopalatine sinuses is mentioned?
Incomplete formation of the sphenoidal septum, leading to bilateral discharge even if only one side is affected.
What is the clinical significance of the rostral maxillary sinus and ventral conchal sinus communication?
They communicate with the middle nasal meatus via the nasomaxillary opening.
Which sinus is located beneath the rostral brain and optic chiasm in horses?
The sphenoid sinus.
Perez et al VS 2021 Where within the nasopharynx was the fenestration site located in cadavers?
Midway between the vomer and dorsal conchal wall - For the
palatine bone, 10–15 W continuous wave varying from 1 to 2 cm focal distance was used to create the necessary 12–
15 mm fenestration mucosa required 460 J and bone 1890 J
What are the most common clinical signs of diseases involving the external nares in horses?
Reduced airflow, nasal stertor, and facial distortion.
Perez et al VS 2021 What condition was identified in the clinical case’s sphenopalatine sinus?
A. A benign cyst
B. A soft tissue abscess
C. An undifferentiated carcinoma
D. A vascular anomaly
C. An undifferentiated carcinoma
Perez et al 2021 What tool was used to ablate the mucosa and palatine bone during the procedure?
A. Bronchoesophageal forceps
B. Flexible endoscope
C. CO2 laser fiber
D. Standing CT scanner
C. CO2 laser fiber - Endoscopically guided fenestration of the rostral palatine bone
within the nasopharynx using CO2 laser in the standing horse provided good
access and visualization of the palatine portion of the SPS.
FIGURE 1 Multiplanar reconstructed CT images ((A) sagittal, (B) transverse, and (C) dorsal views) at the level of the sphenopalatine
sinus (SPS) of the clinical case when initially presented for right intermittent epistaxis. Note the soft tissue/fluid attenuating mass within the
right sphenopalatine sinus (asterisks). Red arrow indicates proposed site of fenestration of right rostral palatine bone
FIGURE in Perez et al 2021 VS
What clinical signs may indicate laceration of the external nares?
Reduced airflow,
nasal stertor,
and facial distortion.
Why should sinus and neurological deficits together raise suspicion of disease?
Because disease processes in this area can result in erosion of thin bone plates separating sinuses from cranial nerves.
What is the new name for what was previously called sebaceous cysts in horses?
Epidermal inclusion cysts.
What diagnostic method is pathognomonic for epidermal inclusion cysts?
Visual inspection of homogenous, thick brown aspirated material during cytological examination of a fine-needle aspirate.
What is the age variation for horses with epidermal inclusion cysts?
2 to 18 years old.
Why should laceration of the nares not be underestimated in performance horses?
Nares represent the point of maximal airflow resistance, and suboptimal repair could lead to undesirable airflow restriction during exercise.
What is the recommended treatment for epidermal inclusion cysts in horses?
Single intralesional 10% formalin administration.
Latero-45° Ventral-Lateral Oblique Projections
What is the suggested technique for standing surgery to remove epidermal inclusion cysts?
Incise the skin and subcutaneous tissue, remove the cyst by dissection, and take care not to rupture the cyst wall.
What other technique beside direct incision is mentioned for removing epidermal inclusion cysts from the nasal diverticulum?
Lancing the cyst into the nasal diverticulum through a stab incision, followed by cyst lining eversion using a burr.
What is the common outcome after treatment of epidermal inclusion cysts in horses?
Cysts either resolve spontaneously or are manually removed as small, desiccated structures.
(R) Normal sinus anatomy. Yellow (Frontal) Red (Dorsalconchal) Green (Rostral Maxillary) Purple (Caudal Maxillary) Blue (Sphenopalatine)
Latero-30° Dorsal-Lateral Oblique Projections
name the projection
Dorsal-Ventral Projection
Diagnosis
Periapical sclerosis
There are many signs of apical infection described in the literature. 1 of the earliest signs reportedis loss of the lamina dura surrounding the tooth. Recent studies have shown this sign to be highlysensitive but very poorly specific, meaning a high degree of false positives which is not desirable in aclinical situation. The same study showed clubbing of the roots, periapical halo formation and periapicalsclerosis to be the most useful signs of periapical infection.
describe endoscopic image
L) Cadaver specimen showing the nasal passageways being divided by the dorsal and ventral conchae.(R) Endoscopic appearance of the middle nasal meatus
Septum on the right
Endoscopic images of the sinus drainage angle (L) and an inflamed endoturbinate (R). Both cases havedischarge from the sinus drainage angle.
Diagnosis
Endoscopic image of a sinus cyst protruding into the nasalpassageway between the dorsal and ventral conchae
Endoscopic image of a progressive ethmoid haematoma
Name the 2 structures in red and blue
Sagittal computed tomography imageshowing the outline of the dorsal conchal bulla(DCB – red) and ventral conchal bulla(VCB – blue)
The dorsal and ventral conchae are invaginated on their caudal aspects by the dorsal and ventralconchal sinuses respectively and within their more rostral aspect contain the dorsal and ventralconchal bullae. These bullae do not communicate with the paranasal sinuses and may become infectedin dependent of the sinuses.
name the teeth and sinuses
Endoscopic image with inspissated material trapped between the dorsal and ventral conchae
Name the sinus and teeth
Name the sinus and teeth
describe the projection and the bone
intraoral DV
What are the external nares and how are they supported in horses?
Openings into the nasal passages; supported by alar cartilages.
What divides the nasal cavity into equal halves?
Nasal septum and vomer bone.
How many major nasal conchae are there in each nasal cavity, and what are their divisions?
Two major nasal conchae; dorsal, middle, ventral, and common meatus.
What is the function of the dorsal conchal bulla and ventral conchal bulla?
They are air-filled structures separate from the paranasal sinus network.
How many pairs of sinuses make up the horse’s paranasal sinus system?
Seven pairs.
How does the volume of the bullae correlate with head size and age in horses?
head size and age in horses? Older large-headed horses have larger bullae than younger, small-headed horses.
What is the term for the communication between the frontal sinus and dorsal conchal sinus?
Conchofrontal sinus.
What are the common clinical signs of diseases of the nares, and why should lacerations be carefully repaired?
Reduced airflow,
nasal stertor, and
facial distortion;
lacerations can cause airflow restriction during rigorous exercise.
Where is the sphenopalatine sinus located, and what structures is it associated with?
Usually contiguous with the** palatine sinus; **
associated with the calvarium and cranial nerves II, III, IV, V, and VI.
What is the alternative name for epidermal inclusion cysts, and where are they located?
Atheromas; dorsolateral aspects of the nasal diverticulum.
What is the treatment option using a single intralesional 10% formalin administration?
Reported for treating intradermal inclusion cysts with complete resolution in all instances.