3. Introduction
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•
•
The Pterygopalatine fossa is a small bony
space between the posterior surface of
maxilla and the pterygoid process of the
sphenoid bone
It is pyramidal in shape
It functions as a neurovascular conduit
4. Boundaries
ANTERIOR: Superomedial part of Posterior
surface of maxilla
POSTERIOR: Lateral pterygoid plate and also a
part of medical plate
MEDIAL: Perpendicular plate of palatine bone
LATERAL: Pterygomaxillary fissure
SUPERIOR: Under surface of body of sphenoid
INFERIOR: The posterior wall meets the anterior
wall and between them is greater palatine canal
Pterygomaxillary fissure
Greater wing of sphenoid
Pterygoid process
Perpendicular plate of palatine
bone
Pyramidal process of palatine
bone
Posterior surface of maxilla
Pterygopalatine fossa
Zygomatic bone
5. Communicatio
ns
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•
•
•
•
With infratemporal fossa via pterygomaxillary
fissure
With orbit via inferior orbital fissure
With middle cranial fossa via foramen rotundum
With nasal cavity via sphenopalatine foramen
With oral cavity (inferior aspect of hard palate)
via greater palatine canal
Inferior orbital fissure
Palatovaginal
canal
Sphenopalatine foramen
Foramen
rotundum
Pterygoid canal
Palatine canal
Alveolar foramen
7. Contents
3rd part of maxillary artery and its branches
Maxillary nerve
Pterygopalatine ganglion and its branches
Nerve of pterygoid canal (Vidian nerve)
Fat (Bichat’s)
8. Maxillary artery
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•
•
•
The main arterial supply to the infratemporal fossa
Largest terminal branch of the external carotid artery
The maxillary artery passes through the pterygomaxillary f i
ssure from the infratemporal fossa
into the pterygopalatine fossa, where it terminates as the third part of the maxillary artery
It gives off numerous branches including the posterior superior alveolar, infraorbital,
sphenopalatine, and greater palatine arteries
9. •
•
•
Divided into three parts by lateral pterygoid muscle.
1st Part:
In front of the stylomandibular ligament along the lower border of the lateral pterygoid
2nd Part:
Deep to lateral pterygoid muscle up to pterygomaxillary fissure
3rd Part:
Enters pterygomaxillary fissure into pterygopalatine fossa
10. 1st Part 2nd Part 3rd Part
Deep auricular
Anterior tympanic
Middle meningeal
Accessory
meningeal
Inferior alveolar
Deep
temporal
Masseteric
Pterygoid
Buccal
Posterior Superior
alveolar
Infra orbital
Greater palatine
Sphenopalatine
Pharyngeal
Artery of pterygoid canal
Branches
12. •
•
•
Posterior superior alveolar artery:
The posterior superior alveolar artery arises from the maxillary artery within the
pterygopalatine fossa and runs through the pterygomaxillary f i
ssure onto the maxillary
tuberosity
It gives off branches that penetrate the bone here to supply the maxillary molar and premolar
teeth and the maxillary air sinus, and other branches that supply the buccal mucosa
Occasionally the posterior superior alveolar artery arises from the infraorbital artery
13. •
•
Infraorbital artery:
The infraorbital artery enters the orbit through the
inferior orbital fissure.
It runs on the f l
oor of the orbit in the infraorbital groove
and infraorbital canal and emerges onto the face at the
infraorbital foramen to supply the lower eyelid, part of
the cheek, the side of the external nose, and the upper
lip.
Infraorbital artery
In inferior orbital
foramen
•
•
Anastomoses:
Ophthalmic a.
Facial a.
14. •
•
While within the infraorbital canal, it gives off the anterior superior alveolar artery which runs
downwards to supply the anterior teeth and the anterior part of the maxillary sinus. A middle
superior alveolar artery is also often described.
When present, it branches from the infraorbital artery within the infraorbital canal and runs
inferiorly along the lateral wall of the maxillary sinus towards the region of the canine and
lateral incisor teeth and anastomoses with the anterior and posterior superior alveolar arteries.
15. •
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•
Artery of the pterygoid canal:
The artery of the pterygoid canal (Vidian artery) arises as a branch of either the distal part of
the maxillary artery (70%) or the petrous segment of the internal carotid artery (30%).
It passes through the pterygoid canal and anastomoses with the pharyngeal, ethmoidal and
sphenopalatine arteries in the pterygopalatine fossa and with the ascending pharyngeal.
Accessory meningeal, ascending palatine and descending palatine (occasionally) arteries in
the oropharynx and around the pharyngotympanic tube.
16. •
•
Through these complex anastomoses, the artery of the pterygoid canal contributes to the
supply of part of the pharyngotympanic tube, the tympanic cavity, and the upper part of the
pharynx.
It may also anastomose with the artery of the foramen rotundum, and so communicate with
branches of the cavernous portion of the internal carotid artery.
Artery of the
pterygoid canal
Lesser palatine
artery
Descending
palatine
artery
Greater
palatine
artery
17. •
Pharyngeal artery:
The pharyngeal branch of the maxillary artery passes through the palatovaginal canal,
accompanying the nerve of the same name, and is distributed to the mucosa of the nasal roof,
nasopharynx, sphenoidal air sinus, and pharyngotympanic tube.
18. •
Greater (descending) palatine artery:
The greater palatine artery leaves the pterygopalatine fossa through the greater (anterior)
palatine canal, within which it gives off two or three lesser palatine arteries.
Artery of the
pterygoid canal
Lesser palatine
artery
Descending
palatine
artery
Greater
palatine artery
19. •
•
•
The lesser palatine arteries emerge onto the palate through the lesser (posterior) palatine
foramen, or foramina, and supply the soft palate.
The greater palatine artery supplies the inferior meatus of the nose, then passes onto the
roof of the hard palate at the greater (anterior) palatine foramen and runs forwards to
supply the hard palate and the palatal gingivae of the maxillary teeth.
It gives off a branch that runs up into the incisive canal to anastomose with the
sphenopalatine artery, and so contribute to the arterial supply of the nasal septum.
20. •
Sphenopalatine artery:
The sphenopalatine branch of the maxillary artery passes through the sphenopalatine
foramen and enters the nasal cavity posterior to the superior meatus.
Sphenopalatine
artery
Posterior lateral
nasal branch
Posterior septal
branch
Kiesselbach’s
area
•
•
•
Anastomoses:
Ethmoid aa.
Superior labial a.
Greater palatine a.
21. •
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•
From here its posterior lateral nasal branches ramify over the conchae and meatuses,
anastomosing with the ethmoidal arteries and nasal branches of the greater palatine artery to
supply the frontal, maxillary, ethmoidal, and sphenoidal air sinuses.
The sphenopalatine artery next crosses anteriorly on the inferior surface of the sphenoid and
ends on the nasal septum in a series of posterior septal branches which anastomose with the
ethmoidal arteries.
A branch descends on the vomer to the incisive canal to anastomose with the greater palatine
artery and the septal branch of the superior labial artery.
22. Maxillary nerve
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•
•
•
It is the 2nd part of trigeminal nerve
It contains only general sensory fibers
Leaves middle cranial fossa and enters pterygopalatine fossa via foramen rotundum
passes anteriorly through pterygopalatine fossa and enters the orbit via inferior orbital
fissure where it becomes the infraorbital nerve
This infraorbital nerve lies first in infraorbital groove and then in infra orbital canal and
emerges onto face through infraorbital foramen
23. Branches
Maxillary nerve
Zygomatic nerve
Infraorbital
Posterior superior
alveolar nerve
Zygomaticofacial
Zygomaticotempor
al
Middle superior
alveolar nerve
Anterior superior
alveolar nerve
Nasal branch
Palpebral branch
Labial branch
(Via infraorbital
foramen)
Ganglionic
branches
Dural branch
24. In Pterygopalatine fossa
Zygomatic branch
Enters orbit through infra orbital
f issure, through zygomatic
orbital foramen and supplies
lacrimal gland and zyg-facial and
zyg-temp
Ganglionic branch
Pte ry gopalatine ne rve s to
ganglion
Posterior superior alveolar nerve
Enters post surface of maxilla
and supply molars
26. Pterygopalatine ganglion
The pterygopalatine ganglion is a parasympathetic ganglion found in the pterygopalatine
fossa
It is also called as ganglion pterygopalatinum or Meckel’s ganglion or nasal ganglion or
sphenopalatine ganglion
It is one of four parasympathetic ganglia of the head and neck (The others are submandibular
ganglion, otic ganglion, and ciliary ganglion)
27. •
Parasympathetic (Secretomotor):
Superior salivatory and lacrimal nucleus (pons) – Facial nerve – In mid ear travels through
greater superficial petrosal nerve – Through a hiatus enters mid cranial fossa – Enters F.
Lacerum – Joins with deep petrosal nerve (sympathetic) – Vidian nerve – Pterygoid canal –
Pterygopalatine fossa, Relayed by PPt Gang – Post gang fibers supply lacrimal, Nasal,
Palatine glands.
28. •
•
Sympathetic (Vasoconstrictor):
From T1 and T2 segments of spinal cord – Superior cervical sympathetic ganglion –
Plexus around internal carotid – Deep petrosal nerve at the level of F. Lacerum – Passes
through the gang without relaying – Supplies the same glands.
Sensory:
From ganglionic branches of maxillary nerve.
29. Branches
Ascending Descending Posterior Medial
Orbital branches
(Secreato motor to
lacrimal and
ethmoidal air cells)
Greater palatine nerve
(supplies hard palate
and gives off postero
inferior lateral nasal
branches)
Pharyngeal branch
(Supplies pharyngeal
mucosa around the
eust. tube orifice)
Posterio-superior
medial nasal (Antero-
inf septum and floor of
nose)
Lesser palatine nerve
(Supply soft palate and
tonsils)
Nasopalatine nerves
(Roof of the mouth)
Postero-superior lateral
nasal (upper lateral
quadrant of nasal
septum)
30. •
•
It is also called the nerve of pterygoid canal
It is formed by
i) Greater petrosal nerve:
ii) Deep petrosal nerve:
The greater petrosal nerve carries preganglionic parasympathetic fibers
responsible for lacrimation and nasal gland secretions
The deep petrosal nerve carries sympathetic fibers that regulate blood
vessel constriction and dilation, among other functions
Vidian nerve
31. Course of Vidian nerve
It is located at the cartilaginous substance that fills the foramen lacerum
Passes forward through pterygoid canal accompanied by artery of pterygoid canal
Here, the ascending branch from the otic ganglion joins the nerve
Exits its bony canal in the pterygopalatine fossa, where it joins the pterygopalatine ganglion
33. Artery of pterygoid canal
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•
The artery of the pterygoid canal (Vidian
artery) is an artery that can arise from the
internal carotid (ICA) or external carotid
(ECA), or serve as an anastomosis between
these arteries
It more commonly arises from the ECA
Artery of pterygoid canal
34. •
•
The artery passes backward along the pterygoid canal with the corresponding nerve
It is distributed to the upper part of the pharynx and to the auditory tube, sending into the
tympanic cavity a small branch that anastomoses with the other tympanic arteries
35. •
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•
Vidian canal:
It is a short bony tunnel close to the floor of the sphenoid sinus
It transmits vidian nerve and vessels from the foramen lacerum to the pterygopalatine fossa
According to the CT findings, this canal is classified into:
Type 1- Vidian canal lies completely within the floor of the sphenoid sinus
Type 2- Vidian canal partially protrudes into the floor of the sphenoid sinus
Type 3- Vidian canal completely embedded in the body of the sphenoid bone
36. Fig. The nerves of the pterygoid canal and the pterygopalatine
ganglion.
37. Overview
Anterior wall Post wall of
Maxilla
Inferior orbital
fissure
Orbit Transmits infraorbital
vessels, nerves, and
ascending branches of
the pterygopalatine
ganglion
Posterior wall Lateral and
medial Pterygoid
plates
Pterygoid canal Middle cranial
fossa near F.
Lacerum
Trans vidian nerve and
vessels
Medial wall Perp plate of
palate
Sphenopalatine
foramen
Nasal cavity SP artery BR and PtP
gang branches to np
mucosa
Lateral wall Gap between the
pterygoid plates
and maxilla
Pterygomaxillary
fissure
Infratemporal
fossa
Trans max artery
Superior wall Greater wing of
sphenoid
F. Rotundum Mid cranial fossa Transmits maxillary
nerve
Inferiorly Posterior wall
meets the anterior
wall
Greater palatine
and lesser
palatine canals
Oral cavity roof Greater palatine and
lesser palatine nerves
and vessels
39. •
•
•
1. Trans antral approach:
Given by ‘Golding wood’ – Classic type
Given by ‘Nomura’ – Subperiosteal type
Indications – (i) Vidian neurectomy
(ii) Maxillary artery ligation
40. (i)
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•
Vidian neurectomy:
Indications: (a) Severe intractable VMR
(b) Crocodile tears
(c) Senile nasal drip
(d) Severe recurrent nasal polyposis
Procedure: Under GA
Antrum opened as for Cardwell Luc procedure (to preserve
the Infraorbital nerve)
Elliptical posterior antral window made with chisel cuts after
removing mucosa
43. •
2. Trans nasal approach:
3 types – (i) Endoscopic Trans Sphenoidal
(ii) Trans septal
(iii) Direct trans nasal
44. (i)
Endoscopic Trans Sphenoidal: Under GA
Patient in a ‘semi-flower’ position
Lateralize the middle turbinate
Angled endoscope towards the roof of choana till sphenoid ostium (located just 1.5 cm above
roof of choana
Ostium enlarged circumferentially with bone punches
Care taken inferolaterally, where SP artery and its branches present
After anterior sphenoidotomy, identify the Vidian canal – at the floor of sphenoid sinus
Transection of nerve using an angled probe under direct vision
45.
3. Trans palatal approach:
Procedure: Under GA
Keep Boyle Davis mouth gag
Curving incision 1 cm anterior to posterior margin of hard palate
5 mm bone removed
Incision over mucosa to expose the medial pterygoid plate – removed with a burr
Pterygoid canal identified and 2-3 mm deeply cauterized
46. References
1.
2.
3.
4.
Grey’s Anatomy - 40th edition
Scott-Brown’s Otorhinolaryngology Head & Neck Surgery - 8th edition
Endoscopic Sinus Surgery (Author - Peter John Worlamald) – 4th edition
Rhinology Diseases of Nose, Sinuses, and Skull base (Authors – David W. Kennedy and
Peter H.Hwang)
