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TEMPORAL & INFRA-TEMPORAL REGION
presented by – Dr. Anindya Chakrabarty
Content
General information Temporal region & its contents Infra-temporal region & its contents Clinical importance of this region
INTRODUCTION
A knowledge of the anatomy of the infratemporal and Temporal region and their contents is essential for understanding regarding oro-facial region.
Many of the nerves and blood vessels supplying the structures of the maxillofacial region run through or close to these fossae.
In addition, the infratemporal fossa contains the pterygoid muscles which play an important part in movements of the mandible.
Border of Temporal Region
TRAUMA TO THE TEMPORAL REGION
The bone of calvarium is thinnest in the temporal fossa. Strong blows to the side of the head may cause a depressed fracture, in which a fragment of bone is depressed inward to compress or injure the brain. At the pterion, the middle meningeal artery is easily ruptured following such an injury CAUSING EXTRA DURAL HEMATOMA. The resulting hematoma will compress the brain and could be fatal if untreated. TREATMENT According to the "Guidelines for the Management of Traumatic Brain
Injury, EDH with volume greater than 30 mL should undergo surgical evacuation
This criterion becomes especially important when the EDH exhibits thickness of 15 mm or more, and a midline shift beyond 5 mm
Gillie’s temporal approach
Border of Infra-temporal Region
TEMPORALIS MUSCLE
ORIGIN: floor of temporal fossa & deep surface of temporal fasica
INSERTION: the tendon passes deep to zygomatic arch to be inserted to all coronoid process NERVE SUPPLY: temporal branch from anterior division of mandibular nerve
BLOOD SUPPLY:DEEP TEMPORAL ARTERY
ACTION: Elevation of mandible, Its posterior fibers retract the mandible
Temporalis Muscle as a flap reconstruction This type of flap was first described
by Golovine in 1898. The approach to harvest is through a
temporal rhytidectomy incision and subperiosteal dissection.
Indicationsorbital reconstructionssling for the lower eyelid and lip in facial paralysisReconstruction of oral cavity and oropharynx defect
Temporalis Tendon Transfer as Partof a Comprehensive Approach to Facial Reanimation
REHABILITATION of facial paralysis is one of the greatest challenges faced by reconstructive surgeons today.
The available options for facial reanimation are determined by the duration and cause of the paralysis.
Dynamic muscle transfer remains an excellent option for facial reanimation in patients for whom the options of primary nerve repair, grafting, and nerve transfer are not possible.
The mainstay of this technique is temporalis muscle transfer.
Temporalis tendon transfer provides for improved function and elimination of the telltale signs of temporalis transfer produced by the classic technique.
Orthodromic temporalis insertion transfer involves release and mobilization oftemporalis at the insertion into the coronoid.
The temporalis is then transferred to the oral commissure, effectively eliminating the depression in the temple and any tissue protrusion around the zygomatic arch.
LATERAL PTERYGOID
ORIGIN:1. Upper head: infratemporal
surface of greater wing of sphenoid
2. Lower head: lateral surface of lateral pterygoid plate
INSERTION: pterygoid fovea (in front of neck of mandible) + capsule & articular disc of TMJ
NERVE SUPPLY: from anterior division of mandibular nerve
ACTION:1. Pulls the condylar process
forward to depress the mandible
2. Side-to-side movement
RELATIONS OF LATERAL PTERYGOID
Superficial: temporalis, masseter, ramus of mandible, maxillary artery, buccal nerve
Deep: medial pterygoid, mandibular nerve, middle meningeal artery, otic ganglion
Emerging through its upper border: deep temporal & masseteric nerves
Emerging through its lower border: lingual & inferior alveolar nerves + maxillary artery
Emerging between its 2 heads: buccal nerve, maxillary artery
MEDIAL PTERYGOID
ORIGIN:1. Superficial head: tuberosity
of maxilla2. Deep head: medial surface
of lateral pterygoid plate INSERTION: medial surface
of ramus & angle of mandible
NERVE SUPPLY: from trunk of mandibular nerve
ACTION: 1. Elevation of mandible2. Protrusion of mandible
(when muscles on both sides act together)
3. Side-to-side movement (when muscles on both sides act alternatively)
Clinical notes of venous drainage:
Anastomoses of the pterygoid venous plexus with the facial vein and cavernous sinus represent an important potential pathway for the spread of infection.
Normally, blood from the medial angle of the eye, nose and lips drains down through the facial vein.
Veins in the head, including those of the pterygoid venous plexus, do not have valves, however.
Infections may therefore reverse the flow of blood into the cavernous sinus, resulting ultimately in meningeal infections.
CLINICAL CORRELATION OF INFRATEMPORAL FOSSA AND MANDIBULAR NERVE BLOCK
The pathways are significant clinically because they help describe the consequences of interrupted nerve function, due either to anesthesia or injury. To numb the mandibular teeth for a dental procedure, anesthetic is injected at the lingula of the mandible to block the inferior alveolar nerve. If the needle passes too far posteriorly, it may anesthetize branches of CN VII coursing through the parotid gland.
• CLINICAL CORRELATON-AURICULOTEMPORAL Nerve
• Frey’s syndrome produces flushing and sweating instead of salivation in response to taste of food after injury of the auriculotemporal nerve, which carries parasympathetic secretomotor fibers to the parotid gland and sympathetic fibers to the sweat glands.
• When the nerve is damaged, the fibers can regenerate along each other’s pathways and innervate the wrong gland.
• It can occur after parotid surgery and may be treated by cutting the tympanic plexus in the middle ear.
INFRATEMPORAL FOSSA AND NERVE BLOCKS FOR THE MAXILLA
The posterior superior alveolar artery runs with the nerve(s), but is no more likely to be damaged than arteries in other neurovascular bundles.
The pterygoid venous plexus lies within and around the lateral pterygoid muscle, and should not be damaged unless the needle is inserted too deeply or laterally.
If a positive (venous) aspiration is observed during this procedure, withdrawal will disengage the needle with minimal bleeding resulting—injecting into the friable plexus causes disruption which can lead to haematoma formation and postoperative trismus.
Infection of infratemporal region
Cervicofacial celulitis Infratemporal fossa space infection Submasseteric space infection Pharyngeal space infection Cavernous sinus thrombosis
APPROACHES TO INFRATEMPORAL FOSSA
Several surgical approaches to the infratemporal fossa have been described over the years and some of them have been improved and modified. Basically the various approaches can be grouped under the following categories, which are
Transoral,
Transantral,
Transpharyngeal,
Transmaxillary,
Extended maxillotomy,
Maxillary swing,
Transmandibular,
Transzygomatic ,
Facial translocation,
Transcranial,
Combined
TRANSORAL APPROACH
The superior gingivolabial sulcus posteriorly is close to the tuberosity of the maxilla and provides access to the lower part of the infratemporal fossa.
An approach through this area does not provide enough exposure for removal of tumours,
the view is obstructed by fatty tissue and there is no vascular control.
However, the recess provides access for biopsy purposes
especially if the lesion is located low in the infratemporal fossa.
Occasionally a benign tumour may be removed through this approach.
TRANSANTRAL APPROACH
The antral cavity is entered through a sublabial incision, extending from the level of the canine to the first molar tooth and the mucoperiosteal flap is elevated until the infraorbital foramen, so as to preserve the infraorbital vessels and
A window is made into the anterolateral wall of the antrum large enough to provide good exposure of the complete posterior wall of the maxillary sinus.
The roots of the canine and premolars are preserved.
The antral mucosa on the posterior wall is incised at its junction with the medial, lateral and superior walls, and the mucoperiosteal flap is reflected down.
• The periosteum on the outer surface of the posterior wall is incised along its medial, lateral and superior border and reflected downwards.
• At the end of the procedure the bony posterior wall and the mucoperiosteal flap are replaced.
• This approach is not suitable for tumour excision by itself, but may be combined with other approaches. It is invariably employed for the purpose of obtaining a biopsy.
TRANSPHARYNGEAL APPROACH
The authors Kornfehl et al. have basically described a transpharyngeal approach via the palate.
The nasopharynx is reached via an ‘S'-shaped incision running vertically on the soft palate and on to the anterior pharyngeal arch towards the side of the lesion.
The mucosa of the lateral wall of the nasopharynx is incised vertically, the superior constrictor muscle of the pharynx is split to enter the most medial part of the infratemporal fossa.
Kornfehl et al. employed this approach to extirpate a cavernous haemangioma close to the lateral pterygoid muscle which had been shown not to have any feeding vessels.
This is not a safe approach for tumour excision.
The internal carotid artery is close to the pharyngeal wall and it is not possible to obtain any control on the vessel. The exposure obtained is limited.
TRANSMAXILLARY APPROACH
It was originally described by Langenbeek in 1859 as an osteoplastic technique for tumours of the pterygopalatine fossa.
An incision is placed in the buccal sulcus above the attached gingivae between the maxillary second premolars.
the incision is placed half a centimetre
above the apices of tooth to ensure the viability of the teeth.
A mucoperiosteal flap is raised. The nasal septum is separated from the anterior nasal spine and the maxillary crest and the facial soft tissue are retracted cranially.
• An osteotomy incision is placed, using an electric burr from one maxillary tuberosity to the other.
• The incision passes just under the zygomatic buttress and divides the anterior nasal aperture.
• An osteotomy of the medial wall of the maxilla is performed through the inferior meatus to the palatine canal. At this stage the palate and the inferior portion of the maxilla remain attached by the pterygomaxillary suture, the thin posterior wall of the maxillary sinus and the bone forming the canal of the palatine vessels.
• Using a curved osteotome the maxilla is separated and disimpacted downwards.
• The buttress of bone anterolaterally and at the piriform nasal aperture are preserved so that they can be approximated at closure.
EXTENDED MAXILLOTOMY APPROACH
This is essentially a transantral approach with an extended sublabial incision taken from the midline to the maxillary tuberosity and carried down to the periosteum.
The posterior wall of the maxillary sinus is widely excised allowing access to the pterygomaxillary portion of the tumour.
The medial wall of the maxillary sinus and the nasopharynx is removed. Lateral extension of the tumour can be exposed by removing the lateral wall of the antrum.
It can also be combined with a transpalatal approach. It was described by Krause and Baker who used it mainly for surgical treatment of nasopharyngeal angiofibroma.
TRANSMANDIBULAR APPROACH
The concept of approaching the retromaxillary area through a mandibulotomy is not new and has been advocated by Conley and Barbosa. The infratemporal fossa communicates inferiorly with the neck.
If the mandible is laterally retracted and the medial pterygoid muscle is detached from its mandibular attachment the infratemporal space can be reached.
This approach provides good control of the vessels and nerves and en bloc resection of nasopharynx, posterior maxilla, infratemporal fossa structures, mandibular ramus and parotid gland can be performed.
The procedure has been modified by Attia et al. to obtain wide field exposure without sacrifice of either mandibular function or the sensory supply of the face and oral cavity.
• The mandibular osteotomies are arranged to spare the inferior alveolar nerve and vessels and are positioned under the intercondylar notch above the opening of the mandibular canal and just medial to the mental foramen.
• Detachment of the medial and lateral pterygoid muscles and the sphenomandibular ligament allows the mandibular segment to be reflected superiorly .
• This provides direct access to the infratemporal fossa; osteosynthesis of the mandible and intermaxillary fixation is performed. The procedure preserves function, exposure is good and is cosmetically acceptable.
MAXILLARY SWING Incision – Weber Ferguson incision without
gingivolabial component
Bilateral tarsorraphy should be performed
Inverted “U” shaped incision is marked out on the hard palate
After deepening the facial incision the lacrimal sac should be skeletonized and sectioned at its lower end.
Infra orbital nerve should be sectioned as it comes out of infraorbital foramen.
Periosteum of the inferior orbital wall should be elevated.
Osteotomies should be performed on the frontal process of maxilla and at the maxillo zygomatic suture.
The maxillo ethmoidal junction should be separated using a straight osteotome.
• The mucoperiosteum over the hard palate should be elevated based on the contralateral greater palatine vessels. The ipsilateral greater palatine vessels were cauterized and sectioned.
• A straight osteotome should be placed between the arms of a v shaped notch located on the anterior nasal spine and hammered in order to separate the maxilla down the middle.
• Now the whole maxilla with its attached cheek tissue can be swung like a door laterally exposing the whole of nasopharynx.
• Mass in the naso pharynx can now be removed under direct vision.
• Maxilla can be repositioned after surgery and secured in position by using miniplate and screws.
COMBINATION OF APPROACHES
Radical excision of tumours and the relatively limited access obtained by any single approach have made combined approaches necessary.
It offers the patients the maximum benefit of the technical ‘know-how’ of the surgical team and the best opportunity for surgical excision.
References
- HOLLINSHED- BOOK OF ANATOMY- GRAYS ANATOMY- LAST ANATOMY- ATLAS OF HUMAN BODY- NETTERS- B.D.CHAURASIA- TEXT BOOK OF
ANATOMY- JOHN D LANGDON- SURGICAL
ANATOMY OF INFRATEMPORAL FOSSA
- JATIN SHAH- HEAD AND NECK CANCER