Introduction: Facial pain comprises a heterogeneous and challenging spectrum of diseases. Although
trigeminal neuralgia (TN) is the most common and well defined facial pain syndrome,
many patients present with symptoms more consistent with glossopharyngeal or geniculate
neuralgia (GPN/GN), while other patients describing multiple or ambiguous symptomatologies.
Neurosurgical treatment of medication-refractory facial pain is variable. Microvascular
decompression (MVD) is the standard first-line treatment for TN, but ablative procedures
and stereotactic radiosurgery (SRS) are widespread; by contrast, many authors advocate
for first-line nerve sectioning in GPN and GN, versus MVD alone. We report a patient
who developed TN 7 years after successful GPN treatment, systematically review the
literature on asynchronous facial pain syndromes, and highlight our approach to neurosurgically
managed facial pain.
Methods: Case report and systematic literature review.
Results: A 55-year-old man presented with acute, intermittent, shock-like, pulsatile right
pharyngeal pain with radiation to the right ear, intensely triggered by swallowing.
Although he initially responded well to carbamazepine and gabapentin, severe pain
recurred within months, and he underwent right retrosigmoid craniotomy, MVD of a compressive
PICA loop, and sectioning of the glossopharyngeal nerve and upper vagal rootlets.
Postoperatively, GPN symptoms resolved completely, and durable pain relief lasted
6 years. At that time, the patient developed new right-sided cheek and eye pain, worse
over V2, with reproducible mechanical triggers and partial improvement on carbamazepine.
The patient was returned to the OR, and via the same retrosigmoid craniotomy the trigeminal
nerve was approached and noted to be under compression from both a large petrosal
vein complex laterally an aberrant SCA loop superiorly. The venous branch in contact
with the nerve was isolated, coagulated, and divided, and SCA loop were mobilized
superiorly and buttressed with pledgets. The patient again made an excellent neurologic
recovery, and remains pain-free as of 6-month follow-up.
In addition to our patient, systematic literature review identified 7 preceding cases
of asynchronous TN and GPN with a true asymptomatic interval and unambiguously discrete
symptomatologies. Overall, TN preceded GPN in 6 (75%), and median time to secondary
syndrome was 24 months (range: 3–92). Symptoms were ipsilateral in 6 (75%) and contralateral
in 2 (25%), with 63% of all symptoms occurring on the left. All patients achieved
durable, complete pain relief, and 6 were able to discontinue all medications (75%).
No major complications or mortalities were reported.
Conclusion: TN, GPN, and GN are complex and mutually confounding syndromes, each of which may
respond to a range of treatments, including MVD, nerve section, ablative procedures,
and SRS. Building on our experience with patients such as the present case, we’ve
developed a comprehensive and reliable approach to planning facial pain treatment
in accordance with both clinical and neuroanatomic features. In the presence of convincing
symptoms, we plan an aggressive treatment—via MVD for TN, or nerve section for GPN
and GN. At surgery, we thoroughly inspect the brainstem root entry zones and VII-VIII
complex during all facial pain operations, and pro-actively MVD any compressive vessels,
independent of symptomatology.
