Lateral Temporal Bone Resection

1.     Skin incisions are made either:
a.     A large post-auricular C-shaped flap.
b.     A pre-auricular incision extending into the temporal hairline and down into the neck and incorporating the ear canal.
c.     A Y-shaped flap using a pre-auricular incision and a post-auricular incision.  This option risks loss of the pinna, especially in patients who have had prior radiotherapy.
2.     Simple mastoidectomy is performed identifying the tegmen, sigmoid sinus, horizontal semicircular canal
3.     The operating microscope is brought in, and the antrum widened to identify the incus and malleus.
4.     The root of the zygoma is drilled to identify the capsule of the temporomandibular joint (TMJ).
5.     Bone lateral to the ossicular chain between the ear canal and tegmen is removed until the temporomandibular joint capsule is exposed.
6.     The facial recess is then opened.
7.     The facial nerve is identified and traced to the stylomastoid foramen.
8.     The digastric ridge is drilled away to expose the underlying muscle.
9.     A bony cut is made inferior to the ear canal and lateral to the facial nerve at the stylomastoid foramen to liberate the mastoid tip.
10.  The soft tissue attachments of the mastoid tip are divided with electrocautery.
11.  The facial recess is extended, and the corda tympani nerve is sacrificed.
12.  Drilling is performed between the annulus and the facial nerve until the hypotympanic air cells are reached.
13.  The inferior tympanic ring is drilled down to expose the soft tissue anterior to the ear canal.
14.  The bone along the annulus is divided through hypotympanic air cells until the carotid canal is reached.
15.  The carotid artery can typically be visualized at the posterior/inferior aspect of the eustachian tube orifice.  This serves as an important landmark for staying lateral to the carotid as tympanic ring bone is removed.  Review of the preoperative imaging is crucial for understanding the position of the carotid artery and jugular bulb relative to the tympanic annulus.  
16.  The incus is disarticulated.
17.  The tensor tympani tendon is divided.
18.  Thumb pressure on the ear canal allows it to fracture anteriorly.
19.  A Freer elevator is used to ensure that the anterior annulus is free from the bony annulus.
20.  The ear canal is removed by following the tragal cartilage and anterior ear canal bone medially.  Care is taken to avoid injuring the facial nerve.
21.  Facial nerve decompression can be performed if parotidectomy is being performed concurrently.
22.  Neck dissection for levels II and III is performed at the time of parotidectomy.
23.  Resection of the mandibular condyle is performed when disease extends into the TMJ.
24.  Osseo-integrated implant for cochlear stimulator can be placed.
25.  Reconstruction depends on extent of the resection.
a.     Temporalis muscle flap
b.     Microvascular free tissue transfer

1. Cancer of the ear canal.
2. Parotid cancers that involve the ear canal.
3. Used as a first step for subtotal and total temporal bone resection.

1. Any serious medical condition that prevents a 4 to 6 hour procedure.
2. Unresectable disease, i.e. tumor encompasses the carotid artery, tumor invading brain, lower cranial nerve (IX-XII) deficts, or perineural spread to Gasserian (CNV) ganglion or internal auditory canal.

1. General anesthesia is induced, and the patient is orotracheally intubated. No long-acting paralytics are given.
2. The patient is padded and strapped to the operating table. TED hose and sequential compression devices placed to prevent deep vein thrombosis.
3. The table is turned with the patient¢s head 180 degrees from the anesthesia stand.
4. The scrub tech/nurse is situated across from the surgeon.

1. Biopsy proving cancer in the ear canal.
2. CT scan showing location of tumor. Care is taken to note the extent of the lesion.
3. Patient must be in good general health to undergo this procedure.

Please see the operative description above for the important landmarks to note.

1. Advantage: For tumors that are contained within the ear canal (Pittsburgh Stage 1), LTBR is sufficient treatment.
2. Disadvantage: The surgery produces maximum conductive hearing loss.

1. Hearing loss. A maximum conductive hearing loss is expected. A profound sensorineural hearing loss is possible.
2. Tinnitus.
3. Dizziness.
4. Facial weakness or paralysis.
5. Loss of taste on the anterior 2/3 of the tongue due to corda tympani nerve sacrifice.
6. Loss of pinna. The pinna is at risk when incisions are made anterior and posterior to the pinna, especially if pre-operative radiotherapy has been given.
7. CSF leak.
8. Meningitis.

1. Hearing loss. A maximum conductive hearing loss is expected. A profound sensorineural hearing loss is possible.
2. Tinnitus.
3. Dizziness.
4. Facial weakness or paralysis.
5. Loss of taste on the anterior 2/3 of the tongue due to corda tympani nerve sacrifice.
6. Loss of pinna. The pinna is at risk when incisions are made anterior and posterior to the pinna, especially if pre-operative radiotherapy has been given.
7. CSF leak.
8. Meningitis.

1. Gidley PW. Lateral and Subtotal Temporal Bone Resection. In: Cohen JI, Clayman GL, eds. Atlas of Head & Neck Surrgery. Philadelphia, PA: Elsevier Saunders; 2011:438-449.
2. Gidley PW, Thompson CR, Roberts DB, DeMonte F, Hanna EY. The oncology of otology. The Laryngoscope. Feb 2012;122(2):393-400.