christos georgalas phd mrcs dlo frcs(orl-hns) consultant otolaryngologist academic medical centre,...
TRANSCRIPT
Christos Georgalas PhD MRCS DLO FRCS(ORL-HNS)Consultant OtolaryngologistAcademic Medical Centre, Amsterdam
Access to the sphenoid
Sphenoidotomy
Sphenoid septae
Pre-clival carotid
Axial CTCoronal CT
Internal carotid is vulnerableInternal carotid is vulnerable
Axial CTAxial CT
Internal carotid may project and may not be covered by boneThe septae almost always end on the carotid canal
Septae
SphenoidectomySphenoidectomy
Internal carotid is vulnerable!!Internal carotid is vulnerable!!
Dehiscent carotid canal (8%)
Axial CT Axial CT !!!!!!
Onodi Cell
Posterior ethmoid cell that grows into the sphenoid cell and contains the optic nerve
Axial CT
Sagittal CT
Coronal CT
Sphenoid sinus
Surgery posterior ethmoidsSurgery posterior ethmoids
Optic nerve is vulnerable!Optic nerve is vulnerable!
Coronal CT
Axial CT
11 22
22
1. Projection of the optic nerve into the sphenoid sinus
2. Dehiscent optic nerve (4%)!!!!!!
Sphenoid surgerySphenoid surgery
Types of sphenoid pneumatisation
A. Conchal) B. Pre-sellar) C.Sellar
Sphenoidotomy
• The anterior surface of the sphenoid sinus is approximately 8 cm from the nasal spine and at 15 angle with the horizontal ⁰plane of nasal cavity
The 3+1 ways to enter the sphenoid
A. Superior turbinate
• Lateralise gently medial turbinate
• Posterior and superior to the middle turbinate you can visualise the superior turbinate - Lateralise it!
• Medially you will find the sphenoid ostium
The 3+1 ways to enter the sphenoid
B. Nasopharynx- posterior choanae• Follow nasopharynx
• Find posterior choanae –(exactly where the posterior wall becomes from vertical horizontal)
• 1.6 – 2 cm above that you will find the ostium (4 – 5 times the width of a straight suction
The 3+1 ways to enter the sphenoid
C. Through the posterior septum – rostrum (safer)
• Remove the mucosa from the rostrum
• Follow the bone laterally
• The ostium is 0.5-1 cm from the septum
The 3+1 ways to enter the sphenoid
And the less safe way
D: Through the posterior ethmoids
Perforate the posterior ethmoids aiming postero medially – NOT recommended!!!!
Sphenoidectomy
The posterior septal brach of the sphenopalatine artery runs on the frontal wall of the sphenoid – risk of troublesome (but not dangerous) bleeding
The same branch is used for nasoseptal flap for skull base defects reconstruction!
Enlarge the ostium in an inferior and medial direction with Hayeck punch or drill
If necessary repeat procedure on other side and combine the two enlarged openings medially. Remove distal part of the bony septum.
CA
ON
. Identify the location of the optic nerve (ON) , carotid canal (CA) and opticocarotid recess (OCR) along the lateral sphenoid wall and sella (SE) on the posterior wall
Steps of Surgery
• NASAL PHASE– Diagnostic endoscopy– Localising and opening sphenoid sinus ostium– Preparing mucoseptal flap (if extended approach)
• SPHENOID PHASE – Widening of the ostium and exposure of sphenoid sinus– Exposure of the anterior sellar wall
• SELLAR PHASE– Opening of the sella– Incising the dura– Tumor removal– Closure of the sella
• Completion of surgery (application of flap, closure, packs)
Finding the Sphenoid
• Lateralize or remove lower half of middle turbinate if necessary– identify superior turbinate.
• Inferomedially to the superior turbinate is the sphenoid ostium.
• The sphenoid ostium is 10-15 mm above the choana
The pedicled nasoseptal flap
Hadad G, Bassagasteguy L, Carrau RL, Mataza JC, Kassam A, Snyderman CH, Mintz A. A novel reconstructive technique after endoscopic expanded endonasal approaches: vascular pedicle nasoseptal flap. Laryngoscope. 2006 Oct;116(10):1882-6.
Repeat on other side
Repeat procedure on other side and combine the two enlarged openings medially. Remove distal part of the bony septum and rostrum with blakesley, punch or drill, depending on consistency
Identify sella, carotid bulge, optic nerve, opticocarotid recess and planum sphenoidale – rarely also vidian nerve
OCR
CPS
Enlarge the sphenoid ostium
B. Use initially a Stammberger and subsequently a Kerrison punch – always working medially and inferiorly
A long way to go