Department of Neurosurgery ,
Mayo Clinic , Jacksonville , Florida ,
USA
Glossopharyngeal neuralgia (GPN) is a
condition characterized by sudden, severe pain
in the distribution of the glossopharyngeal
nerve. It can be triggered by talking, yawning,
coughing, and swallowing. Classically, patients
experience a unilateral lancinating and
excruciating pain described as electrical
shock-like pain in the areas around the ear,
tongue, or the mandibular angle. Uncommon
manifestations include cardiac arrhythmias and
syncope during pain episodes. Surgery is
indicated in refractory cases. Bilateral GPN is
rare, and definitive surgical treatment for
bilateral GPN has not yet been reported. In this
case report, a young woman with bilateral GPN
who underwent staged surgery bilaterally is
described. She did not develop life-threatening
cardiac abnormalities postoperatively.
La névralgie glossopharyngée
(GPN) est une affection
caractérisée par une douleur
soudaine et sévère dans le
territoire innervée par le nerf
glossopharyngien. Elle peut être
déclenchée en parlant, en
bâillant, en toussant et en avalant.
Classiquement, les patients éprouvent une
douleur lancinante et atroce unilatérale
décrite comme une douleur semblable
à un choc électrique autour de
l'oreille, à la langue ou à
l'angle mandibulaire. Les manifestations rares
incluent les arythmies cardiaques et la syncope
pendant les épisodes de douleur. La
chirurgie est indiquée dans les cas
réfractaires. La GPN bilatérale
est rare, et un traitement chirurgical
définitif pour la GPN bilatérale
n'a pas encore été
rapporté. Dans ce rapport de cas, une
jeune femme affectée d'une GPN
bilatérale qui a subi une chirurgie
bilatérale est rapportée. Elle n'a
pas développé d'anomalies
cardiaques mortelles après
l'opération.
INTRODUCTION
Glossopharyngeal neuralgia (GPN) is a
condition characterized by severe pain in the
distribution of the glossopharyngeal nerve.
Classically, patients experience unilateral
lancinating pain in the areas around the ear,
tongue, tonsillar fossa, and mandibular angle
with rare findings of syncope and cardiac
arrhythmias during pain episodes. Surgery is
indicated only in refractory cases. Bilateral
GPN is extremely rare. Accounts of staged,
bilateral surgeries for bilateral GPN have not
yet been reported. In this case report, a young
woman who underwent staged surgeries for
bilateral GPN is described. The patient had no
post-operative complication at one year
follow-up.
History of present illness
A female in her early twenties with a
history of a chronic complex facial pain
syndrome presented to the clinic with
intractable left-sided facial pain. She
described a shooting quality of pain behind the
mandibular angle and just below the ear without
radiation to the face, ear, oral cavity, or
oropharynx. Pain episodes were brief, occurred
twenty to thirty times per day, and were
triggered by cold winds, cigarette smoke, and
air inhalation. Touching the face or mouth,
eating, swallowing, speaking, chewing, opening
the mouth, or Valsalva maneuvers did not elicit
the pain. She denied tinnitus, vertigo, ptosis,
redness of the eyes, lacrimation, and
rhinorrhea. The patient had no antecedent
traumatic event or rash. Family history was
noncontributory. The following tests were
performed to detect any underlying systemic
disease, all of which were normal: complete
blood count, vitamin B12, folate, ANA, ENA,
thyroid function, prolactin, ACTH stimulation
test, plasma free metanephrines, and urine
N-methyl histamine. The patient had already been
maximally treated medically for her recent
left-sided intractable facial pain, which
included antihistamines, gabapentin,
oxcarbazepine, baclofen, carbamazepine,
sertraline, oxymorphone, and botulinum toxin
injections. Furthermore, procedures such as
transcutaneous electrical nerve stimulation and
stellate/sphenopalatine ganglion blocks did not
provide complete relief. Left glossopharyngeal
blocks, however, only resolved the pain
temporarily. During these blocks, she did not
develop cardiac arrhythmia or dysphagia. The
patient had a long history of a complex facial
pain syndrome since her early teens. She had
undergone staged surgery for bilateral
trigeminal neuralgia, and surgery for
right-sided GPN two years prior. The latter
consisted of a retrosigmoid craniectomy with
sectioning of cranial nerve (CN) IX and the
upper rootlets of CN X. The current left-sided
facial pain was described as being identical to
her previous right-sided GPN.
Imaging
MRI was negative for abnormal mass, vascular
compression, white matter signal change, or
pathologic contrast enhancement in the regions
of the glossopharyngeal nerves bilaterally
(Figure 1), except for changes attributable to
prior surgical interventions for trigeminal
neuralgia. CT of the head showed no evidence of
abnormal calcification or stylohyoid process
elongation (i.e., Eagle's syndrome).
Preoperative oropharyngeal and cardiac
function tests
The patient's preoperative oropharyngeal
functions were evaluated with vocal cord
function tests and fluoroscopy for swallowing. A
full cardiac examination was also conducted to
detect serious arrhythmia. These tests showed no
evidence of an increased risk for developing
postoperative cardiac or oropharyngeal
complications.
As viable surgical options, we considered
minimally-invasive procedures such as pulsed
radiofrequency neurolysis and stereotactic
radiosurgery using gamma knife. These methods
have shown varying degrees of benefit in case
reports. However, given that: 1) this patient
did not previously experience complete relief
from transcutaneous electrical nerve stimulation
nor stellate/sphenopalatine ganglion blocks, and
2) sectioning of CN IX and the upper rootlets of
CN X was effective on the right side, we
ultimately deemed that sectioning of the left CN
IX and upper rootlets of CN X would be
effective.
Left suboccipital craniotomy was performed
for sectioning the left CN IX and upper rootlets
of CN X. Electrodes were used for intraoperative
monitoring of CN VII, VIII, X, and XI. The left
suboccipital region was incised guided by the
scar line from the previous microvascular
decompression performed for trigeminal
neuralgia. Adhesions between the arachnoid and
the dura were carefully lysed, and CN XI was
exposed and followed carefully to the jugular
foramen. CN IX and the upper rootlets of CN X
were electrically stimulated, and this elicited
no reaction in the vocal cords. CN IX was
sectioned along with two upper rootlets of CN X.
No significant bradycardia or cardiac arrest
occurred during the surgery. The patient awoke
with no complications postoperatively and had
complete resolution of the pain within the first
few days after surgery. At one-year follow-up,
the patient maintained continued relief from
pain with no associated dysphagia or cardiac
arrhythmias.
DISCUSSION
Although GPN presenting at a young age such
as in this patient is uncommon, several
features,
including the distribution of pain around
the mandibular angle and just below the ear, the
ruling out of psychologic and organic causes
that could elicit facial pain, and a history of
an identical type of pain on the contralateral
side which was resolved with glossopharyngeal
rhizotomy, ultimately led to the diagnosis of
GPN.
Although speculative, it is possible that
the young age of the patient contributed to the
favorable surgical outcome. Also, the fact that
two years had already passed since the first GPN
surgery may have allowed the patient's body to
"adjust" physiologically to sectioning important
cranial nerves bilaterally. These findings
indicate that bilateral sectioning of CN IX and
X may be done safely when performed in a staged
manner, and only when preoperative functional
testing indicates minimal risk of developing
post-operative oropharyngeal and cardiac
complications (e.g., arrhythmia, hypotension,
and cardiac arrest). An extremely careful
selection of patients is key to make this
invasive procedure safe.
