EXERCISE 5

PHOTO ATLAS OF ENDOSCOPIC ENDOMEATAL TEMPORAL BONE DISSECTION

ENDOSCOPIC INTACT BRIDGE ATTICO ANTROTOMY

STEP A – Superior canalplasty.. After removal canal skin or elivation of superior tympano meatal flap the outer attic wall is thinned out along with superior canal wall either with drill or with piezo

STEP B – Creation of Bridge using 0 degree endoscope and drill the attic is entered and the bridge is created. The attic drilling can be extended posteriorly to enter antrum and mastoid

STEP C – Identification of ossicles. Intially the thick bridge covers the ossicles, by thinning the bridge the heads of the ossicles are identified. The prominence of lateral semicircular canal is observed including trabiculea of attic.

STEP D – Removal of incus. After seperation I S joint and incudo malleal joint the incus is removed

Labelling:
1 – Lateral wall of attic
2 – Intact bridge
3 – Attic space
4 – Incus
5 – Lss
6 – incus
M and 7 – Malleus
P – Partially removed bridge
AML – Anterior mallear lig
C – cog
Ssc – Superior semi circular canal
Lss – lateral seni circular canal
FN – Facial nerve
SLC – suoralabyrintine cells
PGC – Pre ganglionic cells
ENDOSCOPIC ENDOMEATAL CADAVERIC DISSECTION OF TEMPORAL BONE

STEP I – Seperation and removal of malleus.
Anterior mallear ligament is cut and malleus is seperated and removed
The anterior mallear ligament is laterally present attaching anterior tympanic spine to process gracilus or process cuneatus .
The chorda tympani is medially placed and in between, the anterior tympanic artery passes.

STEP J – Visualisation of anterior attic space.
once ossicles are removed anterior attic space cochleariform process, chorda, hfn and cog are clearly seen

STEP K – Supralabyrinthine triangle.
supralabyrinthine triangle is visualised including supra geniculate cell system. Supra geniculate fossa approach is good approach to petrous apex endoscopically

AML – Anterior mallear lig
CH – Chordatympani
C – Cog
LSS – Lateral semicircular canal
FN – Facial nerve
SSC – Ampulla of ssc
SLC – Supralabyrinthine cells
PGC – Perigeniculate cells