A kaleidoscopic view into Pterygopalatine fossa and its approaches.

1. PTERYGOPALATINE FOSSA &
ITS APPROACHES
DR.ASHWIN MENON

2. PTERYGOPALATINE FOSSA
• A small space between the posterior surface of the
Maxilla and the Pterygoid process of the Sphenoid
bone.

3. BOUNDARIES
• It can be considered as a pyramidal space:
• ANTERIOR: posterior surface of maxilla below floor
of orbit
• POSTERIOR: lateral pterygoid plate and a part of
medial plate also
• MEDIAL: perpendicular plate of palate
• LATERAL: pterygomaxillary fissure
• SUPERIOR: under surface of greater wing of sphenoid
• INFERIOR: ABSENT (the post wall meets the ant wall and
between them is greater palatine canal)

6. ANTERIOR
WALL
POST WALL
OF MAXILLA
INFERIOR ORBITAL
FISSURE
ORBIT TRANSMITS INFRAORB
VESSELS,NERVES, ASC BR
OF PtP GANG
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
PTERYGOMAXILLA
RY FISSURE
INFRATEMPOR
AL FOSSA
TRANS MAX ARTERY
SUPERIOR
WALL
GREATER
WING OF
SPHENOID
F. ROTUNDUM MID CRANIAL
FOSSA
TRANSMITS MAXILLARY
NERVE
INFERIORLY ABSENT GREATER PALATINE
AND LESSER
PALATINE CANALS
ORAL CAVITY
ROOF
GREATER PALATINE AND
LESSER PALATINE NERVES
AND VESSELS

8. CONTENTS
MAXILLARY NERVE
3RD PART OF MAXILLARY ARTERY
PTERYGOPALATINE GANGLION
NERVE OF PTERYGOID CANAL
Fat (Bichat’s)

10. TRIGEMINAL NERVE

11. BRANCHES

12. BRANCHES

13. MAXILLARY NERVE
•ORIGIN- From a semilunar ganglion in Meckel’s cave
as 2nd part of trigeminal nerve.
•Sensory nerve.

15. IN MID
CRANIAL
FOSSA
MENINGEAL BRANCH DURA
IN
PTERYGO
PALATIN
E FOSSA
ZYGOMATIC BRANCH ENTERS ORBIT THROUGH INFRA ORBITAL FISSURE,
THROUGH ZYGOMATICO ORBITAL FORAMEN AND
SUPPLIES LACRIMAL GLAND AND ZYG-FACIAL AND
ZYG-TEMP
GANGLIONIC BRANCH PTERYGOPALATINE NERVES TO GANGLION
POSTERIOR SUPERIOR
ALVEOLAR NERVE
ENERS POST SURFACE OF MAXILLA AND SUPPLY
MOLARS
IN ORBIT ANT SUP ALV NERVE
(FROM INFRAORBITAL NERVE-
A CONTINUATION OF
MAXILLARY)
MAIN TRUNK AFTER ENTERING ORBIT, GIVES THIS
BRANCH FOR PREMOLARS, CANINE AND INCISORS
MIDDLE SUPERIOR ALV NERVE SEEN AT TIMES
IN FACE TERMINAL BRANCHES PALPABRAL, NASAL, LABIAL, LOWER EYELID, ANT
NASAL APERTURE, ANT CHEEK

17. PTERYGOPALATINE GANGLION
• The pterygopalatine ganglion (ganglion
pterygopalatinum, meckel's ganglion, nasal
ganglion, sphenopalatine ganglion) is a
parasympathetic ganglion found in the
pterygopalatine fossa.
• It is one of four parasympathetic ganglia of the
head and neck. (The others are submandibular
gang., otic gang., and ciliary gang.).

19. PTERYGO PALATINE GANGLION
(HAY FEVER GANGLION)
PARASYMPATHETIC
(SECRETOMOTOR)
SUPERIOR SALIVATORY AND LACRIMAL NUCLEAS (PONS) – FACIAL
NERVE – IN MID EAR TRVELS 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
FIBRES SUPPLY LACRIMAL, NASAL, PALATINE GLANDS
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

21. 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)

22. NERVE OF PTERYGOID CANAL
(VIDIAN NERVE)
• The nerve of the pterygoid canal (Vidian nerve) is
formed by the junction of the great petrosal nerve and
the deep petrosal nerve within the pterygoid canal
containing the cartilaginous substance which fills the
foramen lacerum.
• It passes forward through the pterygoid canal with its
corresponding artery (artery of the pterygoid canal)
and is joined by a small ascending sphenoidal branch
from the otic ganglion. It then enters the
pterygopalatine fossa and joins the posterior angle of
the pterygopalatine ganglion.

24. • Parasympathetic preganglionic fibers from the facial
nerve (contained within the greater petrosal nerve)
which synapse in pterygopalatine ganglion.
• Sympathetic postganglionic fibers from the deep
petrosal nerve which do not synapse in
pterygopalatine ganglion.
• The postganglionic parasympathetic fibers of the
deep petrosal nerve, upon synapsing in the
pterygopalatine ganglion, will distribute to the nose,
palate, and lacrimal gland through various nerves
leaving the pterygopalatine fossa.

25. VIDIAN CANAL
• It is through this canal the vidian nerve passes. This is a
short bony tunnel seen close to the floor of sphenoid
sinus. This canal transmits the vidian nerve and vidian
vessels from the foramen lacerum to the pterygopalatine
fossa.
• According to CT scan findings the vidian canal is
classified into:
 Type I: The vidian canal lies completely within the floor
of sphenoid sinus
 Type II: In this type the vidian canal partially protrudes
into the floor of sphenoid sinus
 Type III: Here the vidian canal is competely embedded in
the body of sphenoid bone

27. ARTERY OF THE PTERYGOID CANAL
• 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.
• 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 which anastomoses
with the other tympanic arteries.

29. MAXILLARY ARTERY
• The main arterial supply to the infratemporal fossa
• Largest terminal branch of the external carotid artery
• The maxillary artery arises just posterior to the neck of
the mandible in the substance of the parotid gland and
courses somewhat obliquely through the fossa to end in
the pterygomaxillary fissure.
• Through its course It usually lies lateral (superficially
to the lateral pterygoid muscle, but it can sometimes lie
on the deep side of the muscle.

30. • Divided into three parts by lateral pterygoid muscle
• BRANCHES:-
1ST PART 2ND PART 3RD PART
IN FRONT OF STYLOMAND
LIGAMENT ALONG THE
LOWER BORDER OF LAT
PTERYGOID
DEEP TO LATERAL PTERY
MUSCLE UPTO
PTERYGOMAXILLARY
FISSURE
ENTERS
PTERYGOMAXILLAY
FISSURE INTO
PTERYGOPALATINE FOSSA
1ST PART 2ND PART 3RD PART
Deep auricular
Anterior tympanic
Middle meningeal
Accessory meningeal
Inferior alveolar
Deep temporal
Masseteric
Pterygoid
Buccal
Post . Superior
alveolar
Infra orbital
Greater palatine
Sphenopalatine
Pharyngeal
 Art.of pterygoid
canal

33. THIRD PART OF MAXILLARY ARTERY
• Enters pterygopalatine fossa through
Pterygomaxillary fissure.
GREATER PALATINE AND LESSER
PALATINE ARTERIES
THROUGH THE GP AND LP CANALS AND SUPPLIES HARD
AND SOFT PALATE
POSTERIOR SUPERIOR
ALVEOLAR ARTERY
MOLARS, PREMOLARS AND MAXILLARY SINUS
SPHENOPALATINE ARTERY ENTERS NOSE THROUGH POSTERIOR PART OF SUPERIOR
MEATUS, THROUGH SPHENOPALATINE FORAMEN
DIVIDES INTO: POST LATERAL NASAL AND POST SEPTAL
ARTERY OF PTERYGOID CANAL SUPPLIES THE ROOF OF THE PHARYNX
PHARYNGEAL ARTERY SUPPLIES ROOF OF NASOPHARYNX
INFRA ORBITAL ARTERY CONTINUATION OF THE MAX ARTERY, ENTERS ORBIT
AND APPEARS IN FACE THROUGH INFRA ORBITAL
FORAMEN
ANTERIOR SUPERIOR
ALVEOLAR (INFRA-ORBITAL BR)
BEFORE EXITING THROUGH THE INFRA-ORBITAL
FORAMEN

35. IMAGING

36. IMAGING

37. Contrast-enhanced axial CT scan shows pterygopalatine
fossa (arrows) between posterior wall of maxillary sinus and
anterior surface of pterygoid process of sphenoid bone.
Fossa is seen as low density because of contained fat.

38. CLINICAL SIGNIFICANCE
• REFERRED OTALGIA:
Mandibular nerve also innervates a portion of ear (by
Auriculo-Temporal branch) and hence pain in
infected lower tooth (by Inferior alveolar branch)
may be referred to ear
• FORAMEN OVALE LESION:
Paraesthesia of mandible, teeth and side of the face
and paralysis of Masticatory muscles, hearing
abberations and jaw jerk loss

39. • HAY FEVER GANGLION:
In allergic states, congestion of the nasal
glands, lacrimal glands and palatine glands
result in running nose and lacrimation due to
stimulation of Pterygopalatine ganglion. Hence
it is called “Hay fever ganglion”

40. NERVE BLOCKS
• INFERIOR ALVEOLAR NERVE
• MAXILLARY NERVE
• MANDIBULAR NERVE

41. INFERIOR ALVEOLAR NERVE BLOCK
• By inserting the needle, lateral to pterygomandibular
raphae, about 6-10mm above the occlusal table of
mandibular teeth, then sliding posteriorly along the
medial aspect of the ramus.
• Approach area of injection from contralateral premolar
region ,with other hand thumb retracting the buccal
mucosa pressing on the coronoid process.
• Vicinity of mandibular foramen can be reached.
• Tongue and skin of chin are also anaesthetised due to
Lingual and mental nerve blockade.

44. MAXILLARY NERVE BLOCK
• By inserting the needle, through the mandibular notch
(gingivo buccal sulcus opp to 2nd molar) and guiding
it 45degrees superiorly and medially, along the
pterygoid plate, until the pterygopalatine fossa is
reached at a depth of 6-7 cm .
• This can be confirmed by absence of bony resistence
and adjusting the angle accordingly.
• Foramen rotundum can be reached.
• Useful in trigeminal neuralgia involving maxillary
division.

46. MANDIBULAR NERVE BLOCK
• By inserting the needle – 4cm deep through
Mandibular notch and sliding the needle posteriorly
along the lateral surface of the pterygoid plates.
• Foramen ovale can be reached.
• Useful in trigeminal neuralgia involving Mandibular
division.

49. JUVENILE NASOPHARYNGEAL
ANGIOFIBROMA
• Spread of a tumor along the axis of Pterygomaxillary
fissure with the expansion of the walls.
• Tumor in the sphenopalatine foramen can spread to
pterygopalatine fossa and through the PtM fissure into
the infratemporal fossa.
• Most important sign in the imaging is the ‘bowing’ of
posterior wall of Antrum.
• They quickly spread to parapharyngeal and carotid
space.

51. APPROACHES TO PTERYGOPALATINE FOSSA
• TRANS ANTRAL APPROACH
• TRANS NASAL APPROACH
• TRANS PALATALAPPROACH

52. TRANS ANTRAL APPROACH
• Golding Wood -1961(Classic)
• Vidian neurectomy
• Maxillary artery ligation
• Nomura -1974 (sub periosteal)

53. VIDIAN NEURECTOMY
Indications:-
• Severe intractable vasomotor rhinitis
• Crocodile tears
• Senile nasal drip
• Severe recurrent nasal polyposis
General anaesthesia-hypotensive-60 mm/Hg
Antrum opened (wider) as for Caldwell Luc
procedure- preserve infra orbital nerve

55. • Elliptical
Posterior antral
window is made
with chisel cuts
after removing
mucosa
• A Zeiss
microscope with
300 mm lens used
to remove only
bone

57. • Exposing
maxillary
artery, cleaning
and application
of occluding
clips and
division.

58. •Artery is
displaced
downwards seek
for maxillary
nerve and trace
upto foramen
rotundum.

59. • Identify and
follow
spenopalatine
bundle medial to
maxillary nerve
and trace it upto
medial butress.

60. Identify and
follow
spenopalatine
bundle medial to
maxillary nerve
and trace it upto
medial butress
where
shenopalatine
artery lies
anteriorly.

61. • Shenopalatine
bundle traced
further
medially to find
the ganglion
where it
diverges to
descending
palatine and
nasal branches.

62. • Shenopalatine
ganglion is found
8mm medial and
inferior to foramen
rotundum.
• A hook is slipped
over divergence of
Shenopalatine bundle
and sickle knife
passed beneath it to
cut VIDIAN NERVE
emerging from
pterygoid canal.

64. The mouth of
canal is then
coagulated with
diathermy.

65. • Surgery is completed with haemostasis
Post op complications
1. Absence of lacrimation
2. Facial analgesia
3. Ophthalmoplegia
4. Infection of antrum

66. Maxillary artery ligation
• Indications:-
1. Acute massive epistaxis
2. Recurrent massive epistaxis
3. Herditary telengectiasis
4. Nasopharyngeal angiofibroma

69. TRANS NASAL APPROACH
• Endoscopic
• Minnis and Morrison -1971(Trans septal)
• Patel and Gaikward -1975 (Direct)

70. Endoscopic Transsphenoidal Approach
• After general anesthesia is administered,
the patient is placed in the semi-Fowler
position.
• Cottonoids soaked with diluted
epinephrine (1:100 000) and cocaine, 10%
benzoylmethylecgonine),are positioned
between the middle turbinate and the nasal
septum to enlarge the space between them
and to obtain decongestion of the nasal
mucosa.

71. • The head of the middle turbinate is delicately
dislocated laterally to further widen the virtual
space between the middle turbinate and the nasal
septum.
• After creation of adequate space between the
middle turbinate and the nasal septum, the
endoscope is angled upward along the roof of the
choana until it reaches the sphenoid ostium,
usually located approximately 1.5 cm above the
roof of the choana.

72. • Once the sphenoid cavity is reached,
coagulation of the area around the sphenoid
ostium is performed. This serves to avoid
arterial bleeding originating from septal
branches of the sphenopalatine artery.
• Ostium enlargement proceeds
circumferentially by use of bone punches; care
must be taken in the inferolateral direction,
where the sphenopalatine artery or its major
branches lie.

73. • Once the anterior sphenoidotomy is
completed, A 70° endoscope is used to identify
the vidian canal, usually at the sphenoid sinus
floor, lateral to the natural ostium. Transection
of the nerve is performed using an angle probe
under direct vision.

74. Intraoperative endoscopic views of
the transsphenoidal approach.
The vidian canal can be visualized
at the floor of the sphenoid sinus.
A probe is used to transect the
vidian canal.
Successful transection of the vidian
nerve is performed by direct vision.

75. • The fragment of the nerve is removed
whenever possible and is sent for
pathologic examination. At the end of the
procedure, hemostasis is obtained, and the
middle turbinate is gently restored in a
medial direction.
• Packing of the nasal cavity- bleeding
from the nasal mucosa- usually removed
on the second day. Most patients are
discharged 2 days after surgery.

76. TRANSNASALAPPROACH
• The patient is prepared, and the sphenoid
ostium is identified as in the
transsphenoidal approach. Sphenoidotomy
is performed near the level of the sphenoid
sinus floor.
• Just enough space is offered for the
entrance of a 4-mm endoscope. The
mucoperiosteum is elevated off the anterior
and inferior surfaces of the sphenoid

77. • The vidian canal can usually be identified
between its exit from the sphenoid bone
and its entrance into the
pterygopalatinefossa, usually medial to the
root of the middle turbinate.
• The nerve is subsequently transected by a
sickle knife or by an angle probe. The
remainder of the procedure is performed as
described for the transsphenoidal approach.

79. TRANS PALATALAPPROACH
• Done under GA
• Boyle – Davis mouth gag
• Curving incision 1 cm anterior to the
posterior margin of hard palate
• 5mm bone removed
• 300mm Zeiss microscope –visualise ET
orifice
• Incision over mucosa to expose medial
pterygoid plate, -which is removed with burr
• Pterygoid canal is 2-3 mm deep- cauterised

80. Maxillary nerve block
• Maxillary nerve may be blocked in PPF by
anaesthetic infiltration to greater palatine
canal
• Also a method of anaesthesia to posterior
superior alveolar nerve
• Indications:
1. Dento facial deformities
2. Maxillary sinus surgeries
3. Diagnostic or therapeutic in trigeminal
neuralgia cases

81. • Two intra oral approaches
i. High tuberosity approach and
ii. Greater palatine canal approach
 High tuberosity approach- direct needle posteriorly
superior and medially along zygomatic and
infraorbital surfaces of maxilla to enter the PPF
• Depth of insertion is measuring distance from
gingival crest of premolar to infra orbital rim on face
 Greater palatine canal approach-7mm anterior to jn.
Of hard and soft palate- a 25 g needle bent at 45
degree parallel to mid sagittal plane-in postero
superior direction-gently rotate the needle as it falls
into the canal