Chapter 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 using overground exercise?
It is currently considered the gold standard for diagnosis
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 2021Where 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 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 sinus and teeth
name the teeth and sinuses
Endoscopic image with inspissated material trappedbetween the dorsal and ventral conchae
Name the sinus and teeth
Name the sinus and teeth
describe the projection and the bone
intraoral DV
Sites for establishing drainage from the paranasal sinusesinto the nasal cavity (cross section of the skull at the level of the firstmolar 109/209). The conchofrontal sinus may be fenestrated at (A) toestablish drainage into the nasal cavity. Fenestration of the ventromedialwall of the ventral conchal sinus at (B) creates ventral drainage of theventral concha sinus into the nasal cavity. This diagram of the skull alsodemonstrates the medial and lateral edges of the frontonasal bone flap(arrows) at this level. The structures within the dashed lines have to beremoved to provide access to the dorsal conchal and maxillary sinuses,ventral conchal sinus, and the nasal passage. a, Dorsal meatus; b, frontalsinus; c, dorsal conchal sinus; d, infraorbital canal; e, rostral maxillarysinus; f, ventral conchal sinus; g, oblique septum between the rostral,and caudal compartments of the maxillary sinus.
What is the procedure being performed?
FIGURE 1 (A) The ventral wire (black) and caudal wire (red)
placed under endoscopic guidance. (B) One end of the caudal wire
(red) is redirected through a Chamber’s catheter directed from caudal
to rostral (not shown) to pass through the trephine opening. This is
repeated through the other nostril to bring the caudal wire around the
intrapharyngeal portion of the septum and through the trephine
opening. (C) Three wires positioned to make final cuts in the septum.1
The black wire cuts the ventral attachment of the septum, the red wire
the caudal aspect, and the green wire cuts the dorsal attachment. The
dorsal wire is passed through the trephine opening through a
Chamber’s catheter,1 without endoscopic guidance. A Chamber’s
catheter (not shown) is passed over the caudal wire to direct the wire in
the direction of the arrow to create a 60 cut relative to the nasal bones.
Diagnosis
Periodontal ligament wideningaround an upper 07
Figure 44-7. Diagram of the skull demonstrating the site for the boneflap technique for exposing the maxillary sinus. The boundaries outlinedby bold dashed lines provide maximal exposure of the maxillary sinuswhile protecting the nasolacrimal duct and infraorbital canal. The longdashed line from the medial canthus to the incisive notch depictsthe approximate course of the nasolacrimal duct. (For a description ofthe margins of the maxillary bone flap, see “Surgical Approaches to theParanasal Sinuses.”)
Figure 44-8. Diagram of the skull demonstrating the site for thefrontonasal bone flap technique for exposing the caudal aspect of thenasal cavity, dorsal conchal sinus, and frontal sinus (a). The long dashedline (b) from the medial canthus to the incisive notch depicts the approximatecourse of the nasal lacrimal duct. (For a description of the marginsof the frontonasal bone flap, see “Surgical Approaches to the ParanasalSinuses.”)
Endoscopic view with the endoscope passed via a frontal portal into the frontal sinus (FS),and directed ventrally towards the caudal maxillary sinus (CMS). Note the well-defined fronto-maxillaryaperture (arrows). The ventral conchal bulla (VCB) can also be seen at the caudal rim of the frontomaxillaryaperture:a) Intact bulla visualized at the rostral edge of the fronto-maxillary aperture. The infra-orbital canal(IOC) can be seen within the caudal maxillary sinus.
What is the diagnosis?
Figure 25.12 Endoscopic appearance of the dorsal and
ventral conchae and the stump of the nasal septum at
10 weeks after surgery. Note the lack of reaction and
thickening along the cut edges. Despite the favorable
appearance of the surgery site, this horse had an abnormal
nasal odor that resolved shortly afterward.
FIGURE 2 Bronchoesophageal forceps guided by an
endoscope in the same nasal passage to grasp obstetrical wire
introduced into the contralateral nasal passage through a
Chamber’s catheter.
FIGURE 3 Two sutures of different colors (size 2 nylon and
polypropylene) through two Chamber’s catheters in the same nostril
to prevent crossing of wires. The sutures are retrieved with the biopsy
instrument so the ventral one is ventrally placed and the dorsal one
is dorsally placed in the nasal passages. The suture ends are tied to
obstetrical wires that are then drawn around the back of the septum
while maintaining correct ventral to dorsal relationships.
what is teh diagnosis
FIGURE 4 (A) Right-sided
choanal atresia in horse 1. Note
the opening into a meatus in the
ethmoturbinates (*) dorsal to the
choanal membrane and the
profuse vascular branching on
the buccopharyngeal membrane.
(B) Same area in horse 1, 4 days
after laser opening of the
choanal atresia that would allow
wire passage.
FIGURE 7 Septum removed from horse 2 with diffuse and
marked thickening caused by Aspergillosis, to demonstrate the
approximately 60 cut required to remove the most caudal end of
the septum in a wide part of the nasopharynx.
FIGURE 8 Entanglement of ventral (black) and caudal (red)
wires with the caudal wire directed at 60 in a Chamber’s catheter
(not shown) in the direction of the arrow. This cuts the septum
while the slack ventral wire can follow through the cut to emerge
through the trephine hole and be disentangled.
FIGURE 9 (A) Remnant edge of the buccopharyngeal membrane (arrow) in horse 1 and demonstrating close proximity to the
ethmoturbinate region day 105 after surgery. (B) Remnant of choanal membrane (arrow) in same horse close to its attachment to the floor of
the nasal passage, day 105 after surgery. Both images demonstrate the enlarged opening into the pharynx.
Surgical enlargement of the nasomaxillary aperture and transnasal conchotomy of the ventral conhcal sinus: two surgical techniques to improve sinus drainge by Bach et al 2019. Mentiones the use of an endoscope which size? What are the instruments to access the VCS?
5.9 mm endoscope and conchotome
What were the 2 surgical trephinations site for SENMAP in the same article??
instruments used in Kolas 2019
diode laser in working canal
middle laparoscopic electrocutery
customised rigid lavage catheter
Perez et al 2020 published a standing trans-nasal endoscopic guided CO2 laser fenestration of the palatine bone to acess the sphenopalatine sinus in a horse. What is the appropriate site to access?
Wihtin the nasopharynx midway between the vomer and dorsal conchal wall. The endoscopic procedure was performed as 2step process via standing sedation due to mucosal bleeding obscuring visualization.
This fenestration allowed biopsy under direct endoscopic visualization with long-handled bronchoesophageal forceps inserted via the ipsilateral middle meatus.
Ostrowska et al. 2019 published Computed tomography characteristics of equine paranasal cysts. What is the characteristic?
Detection of a hyperattenuating cystic wall and the paranasal sinus cyst wall has mineralization
F I G U R E 1 (A-D) Comparison of mineralisation pattern between two groups. A,B, Reformatted parasagittal plane CT image of two
horses showing varying degree and pattern of the paranasal sinus cyst wall mineralisation. A, Extensive spiculated paranasal sinus cyst
wall mineralisation (arrows) in the conchofrontal, caudal maxillary sinus and sphenoid sinuses; kernel H70a, WL 829 HU, WW 3429 HU. B,
Peripheral, focal and linear paranasal sinus cyst wall mineralisation (arrows) in the rostral maxillary sinus; WL 868 HU, WW 3932 HU, kernel
H70a. C, amorphous/swirling internal mineralisation (arrows) of the mass in the caudal maxillary sinus extending from the pituitary fossa
mass (meningioma), WL 596HU, WW 2051HU, kernel H40fa. D, internal mineralisations (arrows) in the rostral maxillary sinus progressive
ethmoid haematoma; WL 891HU, WW 4243HU, kernel H70a
FIGURE 5 Transverse (A,B)
and coronar (C) computed
tomography images before (A) and
after (B,C) performing combined
TCVCS and SENMAP in head
8. The resected portions of the bulla
of the maxillary septum and the
medial wall of the ventral concha
are indicated with yellow dotted
lines (B). Two-tipped white arrows,
distance measured from the incised
medial conchal wall to the bony
base of the ventral conchal sinus (B).
Two-tipped red arrows, distance
measured from the rostral to the
caudal SENMAP incisions of the
ventral conchal wall (5C)
Fig 7: Endoscopic fenestration of the ventral concha using a diode laser fibre (top) and an electrocautery instrument (bottom). Radiographs of a cadaver showing corresponding positions of the endoscope and instrument (left). Endoscopic images of the incision (right) (Cases 3 and 6). VC, ventral concha; DC, dorsal concha; NS, nasal septum; SP, soft palate.
Poyet in EVE 2022 published extranasal approach to access the dorsal and ventral conhcal bullae in horses. Name the landmarks
To access the dorsal and ventral conhal bullae through two rhinocenteses it was performed.
Frontal sinus - 40% of the distance from the medial canthus of the eye to midline and** 2 cm caudal** to the rostral aspect ofthe rostral lacrimal tubercle.
Caudal maxillary sinus - mini sinusotomy was performed** 1 cm** **rostral and 3 cm ventral **to the rostral aspect of the **rostral lacrimal tubercle, **with the needlei nserted perpendicular to the bone
**Rostral maxillay sinus **performed 40% of the distance from the rostral end ofthe facial crest to the level of the medial canthus and 1 cmventral to a line joining the infraorbital foramen and themedial canthus, with the needle directed slightly upward(approximately 30; Figure 2).
