Sinonasal Disease

Question 1

List 10 ddx for epistaxis/serosanguinous nasal discahrge

Answer 1

EIPH

PEH

GP mycosis

Fungal rhinitis

Sinonasal neoplasia

Trauma/skull fracture

Foreign body

Sinus cyst

Ulcerative rhinitis

Rupture of the ventral straight muscles of the head (rectus capitis ventralis and longus capitis)

Question 2

Most common PEH signalment

Answer 2

Middle aged males

Reported age 3-20

Question 3

Histo features of PEH

Answer 3

Capsule consisting of resp epithelium and fiborous tissue

Contains haemosiderophages

May have calcerious deposits

Question 4

Tx options for PEH (3)

Answer 4

Trans-endoscopic intralesional 4% formalin injection (inject until the mass begins to distend), repeated q3-4 weeks until resolution

Sinus flap/trephination and mass extirpation - frontonasal bone flap has the most exposure and versatility

Nd:YAG laser ablation for lesions <5cm diameter

Question 5

% of PEH with bilateral involvement

& % with involvement of the sphenopalatine sinus as determined on CT

Answer 5

50% bilateral

38% involvemet of SPS

Question 6

Sinocentesis (/trephine) site for choncofrontal sinus

Answer 6

60% of the distance from midline to medial canthus and 0.5cm caudal to a line connecting the medial canthi

Question 7

Sinocentesis/trephine site for caudal max

Answer 7

2cm rostral and 2cm ventral to the medial canthus

(ie dorsal to the facial crest and rostral to the orbit - facial crest forms the ventral border of the max sinus and dorsal border formed by a line from medial canthus to infra-orbital foramen)

Question 8

Sinocentesis/trephine site for rostral max

Answer 8

40% of the distance from the rostral end of the facial crest to the level of the medial canthus and 1cm ventral to a line joining the infraorbital foramen and medial canthus

This is approx 3 cm dorsal to facial crest and approximately 3 cm caudal to the infraorbital foramen.

Question 9

Methods of haemostasis for sinus surgery

Answer 9

Packing w gauze (most effective) - necessitates tracheotomy if bilateral packing required

Epinephrine soaked gauze packing

Cold physiologic saline lavage (can’t see how this doesn’t wash clotting factors away)?

Bilateral carotid artery ligation

Liquid nitrogen

Question 10

Label the nerves

Answer 10

A- Facial nerve

B - Trigeminal nerve; maxillary branch

1: Auriculopalpaebral
2: Supraorbital (this is trigeminal)
3: Dorsal buccal
4: Ventral buccal branches of facial nn
5: Maxillary
6: Infraorbital
7: Inferior alveolar
8: Mental

Question 11

In Strand et al (2019 VS) what dx criteria were used to dx alar fold collapse. What breed are over-represented for this condition?

Answer 11

Dx criteria - presence of continuous abnormal expiratory vibrating flutter noise, which coincided with visible inspiratory filling of the nasal diverticula throughout the exercise test and when temporarily suturing the alar folds in a dorsal position alleviated these signs

SBs are over-represented

Question 12

What sx procedure was reported by Strand et al (2019 VS) to treat alar fold collapse?

Describe the main steps

Answer 12

Alar fold resection:

1: GA dorsal w 90° neck flexion
2. 10cm skin incision from the lateral alar caudally to the back of the nasal diverticulum
3. Rochester Carmalt forceps placed along lateral and medial margins of the AF, then AF resected with 10 bade in caudal direction removing as much tissue as poss (incl. the rostral portion of ventral concha) but leaving enough to suture edges in direct apposition
4) The nasal mucosa was sutured to the skin of the nasal diverticulum in a simple continuous pattern with 2-0 polyglactin 910, medially & laterally
5) The lateral ala of the nostril was sutured in 2 layers; the (inner) nasal diverticular skin was sutured with 2-0 polyglactin 910 in a simple continuous fashion, and the external skin was sutured with 2-0 polypropylene in a Ford interlocking pattern.

Question 13

Outcomes following alar fold resection reported by Strand 2019 (VS)

Answer 13

20 of 25 horses had competed after surgery, and 13 of 17 of the harness racehorses had established or improved their km racing time marks

Expiratory nasopharyngeal pressures which were initially elevated, were reduced with suturing and alar fold resection to WNL.

5 unraced horses pre-op didn’t race PO, but none were reportedly dt ongoing AF problems

22/25 owners/trainers were satisfied with outcome

Question 14

What other dynamic URT obstruction may be assoc. with alar fold collapse in SBs (Strand 2019 VS)

Answer 14

iDDSP

Question 15

What 2 surgical procedures were reported by Bach et al (VS 2019) for improving drainage from the paranasal sinuses

Answer 15

1) Endoscopy guided trans-nasal conchotomy of the ventral conchal sinus (TCVCS)
2) Surgical enlargement of the nasomaxillary apperture (SENMAP)

Question 16

Briefly describe the 2 surgical procedures reported by Bach et al (VS 2019) for improving drainage from the paranasal sinuses

Answer 16

1) Trans-nasal conchotomy of the VCS:

a) Scope in middle meatus, VCS conchotomy site was located 10–50 mm rostral to the caudal end of the ventral concha and 15–20 mm dorsal to its ventral border
b) Using electrosurgical conchotomes, Coagulation (80W) of an area of approximately 50 × 15 mm of the caudomedial ventral conchal wall was performed with the ball-tipped conchotome
c) Blade-tipped conchotome inserted at the caudal aspect of the coagulated portion and pulled rostrally for 43-50mm
2) Surgical enlargement of the nasomaxillary aperture:
a) 30mm Galt trephine into CFS
b) A portion of the ventral lamella of the dorsal concha approximately 30–45 mm long and 30 mm wide that was located rostromedially to the frontomaxillary aperture was identified and the mucosal lining cauterised (80 W, coagulation mode) with an electro-thermal scalpel
c) The solid bony lamella was cut along the cauterised lines with a chisel and removed, exposing the underlying bulla of the maxillary septum (BMS).
d) The dorsal aspects of the BMS were cauterised & removed
e) An electrothermal bipolar tissue sealing system was used to make 2 vertical, parallel incisions of the medial wall of the ventral concha (VC) at the rostral and caudal aspects of the resection lines of the BMS & tissue between the incisions removed

Question 17

Main clinical features of sinus cysts

Comment on signalment

Answer 17

Debated in the literature but possible biphasic age distribution of young and then >10yrs. Others report more commonly affecting older horses

Main CSs incl. nasal discharge, facial swelling, epiphora, resp noise, nasal occlusion.

Question 18

Treatment of and reported outcomes for sinus cysts according to Fenner et al (2019 EVJ)

Answer 18

Tx with surgical resection via trephine (n=2) or sinus flap (n-35)

• 76.8% resolution of dz
• 19% recurrence rate
• Complete extirpation likely mandatory for resolution of dz
• Co-morbidities incl. dental dz destruction of the infra-orbital canal were more likely to be present in horses >10yrs; poss dt longer period of CSs before presentation in these
• Although head shaking may develop PO - tends to resolve without specific tx. Equally, those presenting w head shaking usually resolved also

Question 19

What were the main findings of Giovatto and Barackzi (EVE 2019) when describing the radiographic appearance of the dorsal and ventral conchal bullae in cadaver heads?

Answer 19

1. Dorsal and ventral nasal conchae are simple structures, comprising two delicate scrolls of thin, mucosa-covered bone; within each dorsal and ventral nasal concha lies an air-filled bulla = DCB and VCB
2. The DCB was easily identified on straight lateral views in all the equine heads.
3. The rostral border of the VCB was correctly identified on plain lateral radiographs in all the heads of horses aged >5 years, while the location of the caudal border is more difficult to ascertain - not visible in 60% plain rads; generally the caudal border extended further caudally than predicted on plain rads & partially superimposed on the rostral limit of RMS in 60% skulls
4. The radiopacity of the mucosal fold rostral to the VCB was easily identified in all the heads in this study, ∴ this may be used as a landmark in the radiographic identification of the VCB
5. Both more difficult to ID on latero30°dorsal lateroventral rads vs straight lateral, and the DV was not useful for the majority of cases, esp for the VCB
6. Broadly speaking, the larger DCBs are usually located dorsal to the maxillary 07s–09s/10s, & the relatively shorter VCBs are most commonly located dorsal to the maxillary 07s–08s/09s
7. Harder to visualise the caudal and ventral borders of the VCB in horses <5 dt superimposition of maxillary teeth and in ponies dt generalised incr. opacity in the nasal/maxillary region
8. Needs investigating in disease

Question 20

Which 4 muscles dilate the nares & what nerve innervates them

Answer 20

Levator nasolabialis

Caninus

Lateralis nasi

Dilator naris apicalis

Innervated by facial nerve; hence facial nerve paralysis performance limiting in horses exercising at fast work