Surgical Approaches to the Sphenoid Sinus and Pituitary Gland
Presented by Sang-Hoon Chun, M.D.,
April 3, 1997
Comments and Supervision by Kyung Shik Suh, M.D.
HISTORICAL
OVERVIEWS
Schloffer.(1906)
1st extracranial approach through the nose
suffered from permanent nasal obstruction and
crusting
Von Eiselberg(1906) included frontal sinus
Very large tumors even orbital exentration discribed
Forehead flaps to seal off CNS
No antibiotics, Microscope, C-arm
Halstead (1910)
Gingivobuccal sulcus incision - sublabial transseptal
approach
Resected whole septum
Hirsch (1911)
Preserved normal structures and nasal function
Subtotal resection
Cushing (1914)
Combined into the sublabial incision of Halstead and
submucosal septal approach
of Hirsch : lip and external nose raised as one, good exposure
,preserving nasal
function, avoiding facial scar
203 transseptal hypophysectomies 7.38% mortality
rate by 1922
Transcranial approach (1930) Cushing and most American
surgerns
removal of suprasella lesions
Extracranial approaches to pituitary ablation in 1953
Dott and Bailey
learned the transsephenoidal approach from Cushing and
later introduced Guiot
Guiot and Bouche (1960)
490 cases 1.9% mortality rate
Hardy
transseptal transsphenoidal technic
Kern and colleagues
transseptal transsphenoidal approach by way of maxilla-
premaxilla approach
Jankowski (1992)
endonasal endoscopic approach
ANATOMY OF SPHENOID
SINUS
most posteriorly located of the paranasal sinuses.
pneumatization : develop rapidly between 5 and 7 years of
age
complete by age 20 to 25 years
Hamberger's classification
Three varieties
Sellar type (86%) : sella floor bulging into a well
developed sinus(0.4mm)
Presellar type (11%) : cancellous bone of the
sphenoid extends from under the
sella trucica to the anterior sapect of the floor(0.7mm)
Concha type (3%): sphenoid sinus is absent and
entirely filled by cancellous
bone(>10mm)
1. Development
4month : indentified
birth : evagination of sphenoethmoid
recess
3 yrs : begin to grow
after 5yrs : rapid invasion of sphenoid
bone
7 yrs : extended posteriorly to level of sella
trucica
late teens : aerated to dorsum sellae
2 Anatomy
open into sphenoethmoidal recess
capacity : 0.5 - 30 ml
average : 7.5 ml
20 mm in height, 23 mm in length , 17 mm in
width
two sphenoid sinus rarely symmetrical
Septum of sphenoid snius
deviated from the midline.(midline
cases 27%)
oblique or transverse,vertical
case(25%)
accessory septa arising from
synchondroses of the sphenoid
sinus usually asymmetircal, one much larger
and overlapping the other
the two sinus rarely communicated
3.Parasellar anatomy
lateral to the shenoid sinus
: cavenous sinus
internal carotid artery (
posterioinferior surface of the latral sphenoid sinus)
several cranial nerve(occulomotor,
trochlear, abducens, ophthalmic, maxillary
branch of trigerminal nerve)
optic nerve and chiasm
: located in the anterolateral aspect of the
sphenoid roof
4% optic canal bone - absent
above : middle cranial fossa and pituitary
gland, olfactory tract, frontal lobe
laterally : carvenous sinus and teh internal
carotid artery, abducens n.
posteriorly : posterior cranial fossa most
thick bone basillar art. ons
floor : nasopharynx, pterygoid fossa.
Pterygoid canal : 16.2mm long
4.Onodi cells - Lang
Def. : posterosuperior ethmmoidal cells lying within the
sphenoid bone
Sphenoid sinus solely develops in lower half of body of
the sphenoid bone
upper body unites with ethmoid labyrinth 9-12%
surround the optic canal with bone (0.5 - 1.0mm)
reached the anterior wall of the sella trucica
5.Recesses of the sphenodal sinus
Septal recess - sphenovomerine bulla
Ethmoidal recess
Superior and inferior lateral recess
Palatine recess
Inferolateral recess
Pterygoid recess
Posterioradn posterosuperior recess
6.Drainage
poor drainage favor its function
15 % all sinusitis
35 % of all intracranial complication from
nose
drainage is through the cilliary action since the
ostium is located
1.5cm above the floor of the sinus
Drainage interference
a. narrow sphenopalatine recess
b. pathologic blockage : thickening of mucosa,
hyperplasis, polyp
blood supply and innervation - similar to post.
ethmoid cell
Preoperative Evaluation
Active sinus infection is the primary contraindication to a
transnasal intracranial
procedure.
APPROACH TO THE SPEHNOID
SINUS
Absolute Indication for transnasal
- tumor into sphenoid sinus
- intrasellar microadenoma
- tumors with CSF leak
Absolute Contraindication
- sphenoid sinusitis
- intracranial extension
1.Transseptal approach
sublabial transseptal approach
intranasal transeptal approach
external rhinoplasty transseptal
approach
collumellar flap modification
2.Transantral approach
3.Transethmoidal approach
external approach
intranasal approach
4.Transpalatal approach
5.Endoscopic endonasal pituitary surgery
SURGIICAL APPROACH
1.Transseptal sphenoidectomy
Sublabial transseptal approach
after general anesthesia
1% lidocaine with 1:100,000 epinephrine
- injected into the upper buccal sulcus,
septum, floor of the nose.
incision upper labial sulcus
- approximately 5mm superior to the
junction between gingiva & mucosa
premaxillary periostium elevation.
bone and nasal spine is resected as needed for
exposure.
perichondrium is incised over the caudal end of the
right side of the nasal septum.
mucoperiostium is elevated from the inferior lip of
th pyriform aperture
floor of the nose bilaterally
dissection continue on the right side along the
lateral wall of the maxillary crest
superiorly along the right cartilage and bony septum
left nasal floor mucosa elevated the same method but
left septal mucosa is left intact
catilaginous septum is dislocated form the
perpendicular plate & maxillary crest
displaced into the naris
perpendicular plate of the septum is removed until
only vomer remaims
neurosurgical pituitary speculum insertion
sphenoid sinus is entered int the midline with use
of the operationg microscope.
- sphenoid ostia used initially as the
superior and lateral landmarks for safe removal of the
anterior sinus wall
resection of septa
External rhinoplasty - Transseptal approach
standard rhinoplasty incision
columellar flap is raised onto the nasal dome.
(elevation - only midway over the lower
lateral cartilage )
medial crura separated by incising the intercrural
ligaments
Exposing the caudal edge of the quadrilateral
crtilage
and then traditional transseptal approach is
continued.
Septal translocation approach
supine position, head rotated to the
right
xylocaine infiltration as for septoplasty
hemitransfixion incision made ipsilatral to
the side of pathologic involvement
elevation of the mucoperichondrium/periosteum from
the septum of the contralateral side
vomer and perpendicular ethmoid plate
removed
mucosa along the floor ipsilateral to the mass is
incised from the lower aspect of the hemitransfixion
incision anteriorly to the posterior choana
incision : midline of the nasal floor
contralateral mucoperichondrium/periosteum elevated
from septum, maxillary crest and nasal floor
transverse sublabial incision
maxillary crest rmoved with rongeurs and
chisels
self retaining hypophysectomy retractor
insertion
sphenoethmoid complex - surgical manuplation
2. Transethmoidal sphenoidectomy
External approach
endotracheal anesthesia
protection of eye : lubricant and a tarsorrhaphy
stitch
xylocaine injection : septum, trubinates
incision : curvilinear, extending from below the eyebrow
inferiorly along the lateral nasal wall, halfway between the
inner canthus and the dorsum of the nose
elevation of periosteum : along the lateral aspect of the
lacrimal and ethmoid bone,
gently retraction of orbital contents
mobilize the lacrimal sac from surrounding anterior and
posterior lacrimal crest
incise the medial canthal ligament
blunt dissection : reveal lamina papyracea and
frontoethmoid suture line
anterior ethmoidal artery : clipped or
electrocauterization
posterior ethmoidal artery : preservation for landmark of
optic nerve
cf) Anatomic landmark
anterior ethmoidal
artery - 24mm posterior to the posterior lacrimal crest
posterior ethmoidal
artery - 12mm posterior to the anterior vessel
optic nerve - 6mm
posterior to the posterior ethmoidal artery
frontoethmoid suture
line - identifying the level of the anterior cranial fossa
exposing the lacrimal bone, rontal process of
maxilla, lamina papyracea, orbital process of frontal
bone
enter the ethmoid cells through the lacrimal
fossa
removal of ethmoid cells sequentially
exposed anterior wall of sphenoid sinus
removal of anterior wall of sphenoid sinus and
septum of sphenoid sinus
Intranasal
3.Endoscopic endonasal approach of sphenoid sinus
Indication
1) CT evidence of sphenoid disease
: opacification, air-fluid level, mucocele or mucosal thickening
> 2mm
2) Evidence of sphenoid obstruction on endoscopic exam
: edematous tissue, polyps or mucoprulent drainage
3) Recurrent vertex or retro-orbital headache in the prescence of
radiologic endoscopic evidence of paranasal sinus disease
Anesthesia
general anesthesia
xylocaine injection to the septum, nasal floor,
turbinate
recognition of the both the arch of the choana and the end
of middle turbinate
Superior turbinate
: key landmark for identification of sphenoid ostium in both
approach
Transnasal approach
Lateral displacement of middle turbinate with a Freer elevator
Identification of the superior turbinate alonside the nasal
septum
: more inferiorly located superior turbinate than initially
expected
Cutting the superior attachment of the superior turbinate with a
turbinate scissors
Grasping the trasected turbinate with a Blakesley forceps
Displacement of the forceps downward with a gentle twisting
motion
Identification of sphenoid ostium with spoon curette
: located medial to the superior turbinate remnant at the point
when its course along the face of the sphenoid change from a
vertical to a transverse direction
Enlargement of the ostium in an inferior and medial direction
with spoon curette, Hayek forceps or bone rongeur
: keep the curette medial to the superior turbinate attachment
when the sphenoid ostium is being enlarged due to reduce the
injury of skull base, optic nerve or carotid artery
: pass medial to the middle turbinate into the sphenoethmoid
recess
: direct approach to sphenoid ostium through the sphnoehtmoid
recess
Identifying the location of the optic nerve and carotid canal
along the lateral sphenoid wall
Removal of remaining anterior wall of the sphenoid opening
: optimal size of ostium widening : 5-10 mm
Transethmoid approach
: pass lateral to the middle turbinate
: most suitable for coexistent sphenoid and ethmoid disease
through the ethmoid sinus
Endoscopic ethmoidectomy
Identification of the sphenoethmoid angle
: where the roof of the posterior ethmoid sinus meets the face of
the sphenoid sinus
Passing a Freer elevator in a posterior direction along the
lateral surface of the middle turbinate
Cutting the superior attachment of the superior turbinate with a
turbinate scissors
Grasping the trasected turbinate with a Blakesley forceps
Displacement of the forceps downward with a gentle twisting
motion
Identification of sphenoid ostium with spoon curette
: located between the superior turbinate remnant and the sphenoid
sinus in the sphenoethmoid recess
Enlargement of the ostium in an inferior and medial direction
Identifying the location of the optic nerve and carotid canal
along the lateral sphenoid wall
Further enlargement of the sphenoid opening
: optimal size of ostium widening - 10 mm
natural ostium
sphenoid sinus lies at medial inferior
portion of the posterior ethmoidal cell
anterior wall of sphenoid sinus - 7cm posterior the
anterior nasal spine open inferior and lateral
remember the anatomic variations in the relationship
between the optic canal and Onodi cell -
distance to the posterior wall of sphenoid sinus (9cm)
COMPLICATIONS OF SPHENOID
SINUS SURGERY
Nasal complications
Cosmetic (saddle and tip deferomities)
Septal perforation
Infection
Epistaxis
Neurologic complications
Injury to optic nerve and cranial nerves
III,IV,V1,V2
Trauma to optic chiasm
Late prolapse of chiasm into sella
Trauma to hypothalamus
Cerebrospinal fluid leak
Vascular complications
Hemorrhage from internal carotid artery
Hemorrhage from cavernous sinus plexus
EMERGENCIES OF SPHENOID
SINUS
Preoperative state
Acute sinustis with meningitis or other neurologic
signs
- Surgical drainage
Developing visual loss in sellar / parasellar tumor
- surgical decompression, radiation therapy
Intraoperative state
Retrobulbar hemorrhage with proptosis and visual
compromise
- lateral canthotomy, opthalmology
consultation
Persistent hemorrhage from sphenoid or carvenous sinus
region
- interventional arteriography
References :
1. Bailey et al, Approaches to the sphenoid. Head and Neck Surgery-Otolaryngology, 1st Ed. Vol 1, p402-12, J.B. Lippincott, Philadelphia, 1993.
2. Bailey et al, Intranasal sphenoidectomy, Atlas of Head and Neck Surgery-Otolaryngology, 1st Ed p874-7, J.B. Lippincott, Philadelphia, 1993.
3. Johannes Lang, Clinical Anatomy of the Nose, Nasal Cavity and Paranasal Sinuses, Thieme Medical Publishers, New York, 1989.
4.Ralph Metson, Richard E,Gliklich , Endoscopic treatment of sphenoid sinusitis, Otolaryngol Head and Neck Surg 1996 ; 114 : 736-44.
5.Steven D, Endoscopic sinus surgery : Posterior approach, Operative technices in Otolaoryn- gology - Head and Neck Surg 1990 ; 1: 104-7.