Editors: Chelly, Jacques E.
Title: Peripheral Nerve Blocks: A Color Atlas, 3rd Edition
Copyright ©2009 Lippincott Williams & Wilkins
> Table of Contents > Section VII – Pain Blocks > 67 – Trigeminal Ganglion Block
67
Trigeminal Ganglion Block
Miles Day
Rinoo Vasant Shah
Patient Position: Supine.
Indications:Trigeminal neuralgia (“tic douloureux”), cluster headache, ocular pain,
cancer pain, surgical anesthesia, differential neural blockade,
prognostic block for neurolytic procedures.
Needle Size:16-gauge, 32-mm angiocatheter (introducer), 20-gauge curved, blunt
Racz-Finch Kit (RFK needle; Radionics, Burlington, MA) is preferred or
22-gauge b-beveled needle, 3-mL syringe, T-connector tubing.
Medications:0.2% ropivacaine and 2% lidocaine in a 1:1 mixture for block (0.25%
bupivacaine or 0.25% levobupivacaine may be substituted for
ropivacaine). Total volume of 1 to 2 mL with or without 40 mg
methylprednisolone, 4 mg dexamethasone, or 40 mg triamcinolone acetate,
plus Omnipaque (Amersham Health, Buckinghamshire, England) (iohexol)
water-soluble contrast 240 mg/mL (0.5 mL).
Anatomic Landmarks:The trigeminal ganglion lies in the Meckel cave at the apex of the
petrous part of the temporal bone. The mandibular branch exits the
foramen ovale and is partly enclosed by a dural cuff (see Fig. 23-3).
Surface
-
Ipsilateral corner of lip: start 2 to 3 cm lateral.
-
Ipsilateral pupil: aim midline.
-
Ipsilateral auditory meatus: aim along line connecting entry and aim to a point 3 cm anterior to meatus, at proximal zygoma.
Radiographic
Fluoroscopically Guided Technique
After sterile preparation of the region, a submental or
subzygomatic view is obtained. The anteroposterior view shows the
petrous ridge through the orbits; 1 cm medially, it also shows a dip in
the petrous ridge. The C-arm is then angled cephalocaudad and obliquely
to visualize the foramen ovale just medial to the mandible and at the
top of the petrous “pyramid.” A forceps is used to mark the surface
entry point directly over the foramen oval. The site of introduction of
the needle is about 2 cm lateral and 0.5 cm inferior to the labial
commissure. A 16-gauge, 1¼-inch angiocatheter is introduced in
gun-barrel fashion (i.e., through the “eye” of the needle). Then, a
20-gauge blunt, curved RFK needle is inserted through the angiocatheter
in similar gun-barrel fashion toward the medial aspect of the foramen
ovale. Surface anatomic landmarks may help but are usually unnecessary
with fluoroscopy. Once the needle is at the level of at the foramen
ovale, a lateral view is obtained. The needle tip should aim for the
junction of the clivus and petroclinoid ligament. V1 is at this junction. V2 is 50% of the distance between the petrous pyramid and the junction between the clivus and petroclinoid ligament. V3
is at the junction of the clivus and petrous pyramid. The ideal
location of the needle is approximately 1 mm beyond the clivus but
never beyond 2 to 3 mm. Aspirate for blood and cerebrospinal fluid
(CSF) (commonly occurs with sharp but not blunt curved needles) until
negative, then instill the contrast. The trigeminal cistern should
opacify. Initiate sensory stimulation at 50 Hz on a 0- to 2-V scale.
Paresthesias are felt at 0.5 to 0.7 V, while around 2 V a contraction
of the masseter muscle is elicited confirming the right positioning of
the needle. Slowly instill 2 to 3 mL of the local anesthetic and
steroid mixture. This is usually followed by the generation of a pulsed
electromagnetic field radiofrequency at 42°C for a 120-second cycle
times two to three cycles. Standard radiofrequency neurolysis can also
be performed at 67°C for 90 seconds. This latter technique, however, is
associated with a risk of sensory loss in the trigeminal nerve
distribution. After the needle is removed, an ice pack is placed on the
patient, and standard monitoring is maintained.
subzygomatic view is obtained. The anteroposterior view shows the
petrous ridge through the orbits; 1 cm medially, it also shows a dip in
the petrous ridge. The C-arm is then angled cephalocaudad and obliquely
to visualize the foramen ovale just medial to the mandible and at the
top of the petrous “pyramid.” A forceps is used to mark the surface
entry point directly over the foramen oval. The site of introduction of
the needle is about 2 cm lateral and 0.5 cm inferior to the labial
commissure. A 16-gauge, 1¼-inch angiocatheter is introduced in
gun-barrel fashion (i.e., through the “eye” of the needle). Then, a
20-gauge blunt, curved RFK needle is inserted through the angiocatheter
in similar gun-barrel fashion toward the medial aspect of the foramen
ovale. Surface anatomic landmarks may help but are usually unnecessary
with fluoroscopy. Once the needle is at the level of at the foramen
ovale, a lateral view is obtained. The needle tip should aim for the
junction of the clivus and petroclinoid ligament. V1 is at this junction. V2 is 50% of the distance between the petrous pyramid and the junction between the clivus and petroclinoid ligament. V3
is at the junction of the clivus and petrous pyramid. The ideal
location of the needle is approximately 1 mm beyond the clivus but
never beyond 2 to 3 mm. Aspirate for blood and cerebrospinal fluid
(CSF) (commonly occurs with sharp but not blunt curved needles) until
negative, then instill the contrast. The trigeminal cistern should
opacify. Initiate sensory stimulation at 50 Hz on a 0- to 2-V scale.
Paresthesias are felt at 0.5 to 0.7 V, while around 2 V a contraction
of the masseter muscle is elicited confirming the right positioning of
the needle. Slowly instill 2 to 3 mL of the local anesthetic and
steroid mixture. This is usually followed by the generation of a pulsed
electromagnetic field radiofrequency at 42°C for a 120-second cycle
times two to three cycles. Standard radiofrequency neurolysis can also
be performed at 67°C for 90 seconds. This latter technique, however, is
associated with a risk of sensory loss in the trigeminal nerve
distribution. After the needle is removed, an ice pack is placed on the
patient, and standard monitoring is maintained.
Complications:Masticator muscle weakness, corneal analgesia, seizure, coma,
paralysis, total spinal anesthesia, keratitis, bacterial meningitis,
carotid fistula, intracranial hemorrhage, diplopia, death, and facial
or subscleral hematoma.
Tips-
Initially, the needle is directed
downward and laterally. Then, the needle is aimed medially for the
foramen ovale to avoid mouth entry. -
One finger should be placed in the mouth to prevent intraoral entry of the needle.
-
Prophylactic antibiotics and sedation with midazolam and fentanyl are advised.
-
If bone is contacted, the needle is “walked” posteriorly along the skull into the foramen ovale.
-
A 3-mL or smaller syringe should be used.
-
Free flow of CSF is not usually seen with
a blunt, curved needle. The free flow of CSF simply implies that the
needle is too anterior (i.e., Meckel cave, rather than in the
trigeminal cistern). -
If a sharp needle is used, the needle
should be withdrawn until no CSF leaks back; otherwise there is a risk
of total spinal anesthesia. -
Small amounts of local anesthetic should be slowly injected to avoid the disastrous complication of total spinal anesthesia.
P.444
Suggested Readings
Mathews
ES, Scrivani SJ. Percutaneous stereotactic radiofrequency thermal
rhizotomy (RTR) for the treatment of trigeminal neuralgia. Mt Sinai J Med 2000;67:288–299.
ES, Scrivani SJ. Percutaneous stereotactic radiofrequency thermal
rhizotomy (RTR) for the treatment of trigeminal neuralgia. Mt Sinai J Med 2000;67:288–299.
Raj PP. Trigeminal block and neurolysis. MD Consult Pain Medicine, www.mdconsult.com. January 7, 2002.
Tew JM, Taha JM. Treatment of trigeminal and other facial neuralgias by percutaneous techniques. In: Youmans J, ed. Neurological surgery, 4th ed. Philadelphia: WB Saunders, 1996:3386–3403.
Waldman SD. Blockade of the gasserian ganglion. In: Waldman SD, ed. Interventional pain management, 2nd ed. Philadelphia: WB Saunders, 2001:316–320.