Learning Objectives
- •
Learn the common causes of facial pain.
- •
Develop an understanding of the unique anatomy of the trigeminal nerve.
- •
Develop an understanding of the sensory innervation of the face.
- •
Develop an understanding of the causes of facial pain.
- •
Develop an understanding of the differential diagnosis of facial pain.
- •
Learn the clinical presentation of trigeminal neuralgia.
- •
Learn testing options to diagnose facial pain.
- •
Learn how to use physical examination to diagnose facial pain.
- •
Develop an understanding of the treatment options for the various types of facial pain.
Brenda Brown
Brenda Brown is a 66-year-old bookkeeper with the chief complaint of “horrible electric shocks in my face.” Brenda stated that for the last 6 weeks, she has been experiencing electric shocks in her right jaw that “come out of nowhere and then go away as quick as they come.” Brenda started crying and said, “Doctor, I just don’t know how much more of this pain I can take! It’s horrible, worse than anything you can imagine.” Between sobs, she said,” I wouldn’t wish this pain on my worst enemy. I can’t eat, drink, or clean my teeth. I’m living on lukewarm oatmeal and even that triggers the shocks.” I asked Brenda if she had ever had anything like this before and she shook her head no. “Any fever or chills?” and again she shook her head no. “Is the pain there all of the time?” I asked. Brenda took a couple of deep breaths in an effort to calm down, then she said, “I am so sorry, Doctor, but I am just so played out. But to answer your question, the pain comes and goes. It hits me out of nowhere. Within a second or two, I am crying out in pain. My face jerks like it’s trying to get away from the pain, and as quick as it comes, it is gone. Then if I sit quietly there is no pain; then out of nowhere, it hits again. It is relentless.”
“Doctor, the pain can hit and wake me up from a sound sleep. If I roll over onto my right side, the touch of the pillow is all it takes to trigger the pain. I have been sleeping in my recliner for the last month. At first, I thought I had a bad tooth, but I went to the dentist and he said he thought the pain was in my nerves. I still have nightmares about the dentist examining me. It was like torture. But honestly, I would let him pull out all of my teeth without local if it would stop this pain.” Brenda started crying again, and the crying triggered paroxysm of pain.
I worked to calm down Brenda, and then asked her to point with one finger to show me where it hurt the most. She pointed to the angle of the right mandible, taking great care not to touch it. “Doctor, this is where the shocks hit, but I really can’t tell where they come from. They come on so fast and with such force that I don’t know which end is up. It takes all of my strength to keep from screaming.”
I told Brenda that we would figure this out and that I would do everything in my power to stop the pain. I asked if I could examine her and she became upset again and said, “Doctor, please don’t touch my jaw! Please don’t. I can’t take much more of this. Go ahead, but please don’t touch my jaw!”
On physical examination, Brenda was afebrile. Her respirations were 18 and her pulse was 84 and regular. Her blood pressure was 148/94. Brenda’s fundoscopic examination was normal as was the remainder of her eye examination. Taking care not to touch her, I had Brenda open her mouth, which triggered another paroxysm of pain. I didn’t see any gross abnormalities, but her dental hygiene was pretty bad. Her cardiopulmonary examination was normal. I did not examine the thyroid or palpate for neck adenopathy in an effort to avoid triggering any more pain. Brenda’s abdominal examination revealed no abnormal mass or organomegaly. There was no costovertebral angle (CVA) tenderness. There was no peripheral edema. Her low back examination was unremarkable. Visual inspection of the face was normal bilaterally. I noted that Brenda experienced facial tics with the paroxysms of pain. A careful neurologic examination of the upper and lower extremities revealed no evidence of peripheral or entrapment neuropathy. Her deep tendon reflexes were normal, and there were no pathologic reflexes or other abnormalities of the neurologic examination. I told Brenda that I was pretty sure I knew what was going on and that the good news was there were many treatment options to begin immediately. Brenda started crying again and kept saying, “Thank you, God. Thank you, God.”
Key Clinical Points—What’s Important and What’s Not
The History
- ◼
No history of previous facial pain
- ◼
No fever or chills
- ◼
Recent onset of unilateral facial pain characterized by electric shocklike pain centered at the angle of the right mandible
- ◼
Onset to peak of seconds to 1 minute
- ◼
Pain is episodic, with pain-free periods
- ◼
Pain triggered by swallowing, chewing, cleaning teeth
- ◼
Trigger areas in the third division of the trigeminal nerve on the right
- ◼
Recent normal dental examination
- ◼
Sleep disturbance
- ◼
High degree of anxiety regarding pain
The Physical Examination
- ◼
Patient is afebrile
- ◼
Trigger areas in the third division of the trigeminal nerve on the right
- ◼
Facial tics associated with pain
- ◼
Poor dental hygiene
- ◼
Otherwise normal neurologic examination
- ◼
Normal fundoscopic examination
- ◼
No fever
Other Findings Of Note
- ◼
Normal cardiovascular examination
- ◼
Normal pulmonary examination
- ◼
Normal abdominal examination
- ◼
No peripheral edema
What Tests Would You Like to Order?
The following tests were ordered:
- ◼
Magnetic resonance imaging (MRI) of the brain with special attention to the brainstem
- ◼
Magnetic resonance angiography (MRA) of the cerebral circulation
- ◼
Erythrocyte sedimentation rate
Test Results
- ◼
MRI of the brain with special attention to the brainstem reveals a neurovascular conflict on the right side with the trigeminal nerve compressed between the supracerebellar artery and the petrosal vein ( Fig. 13.1 ).
- ◼
MRA revealed a dolichoectatic basilar artery, touching the left trigeminal nerve ( Fig. 13.2 ).
- ◼
Erythrocyte sedimentation rate was reported as 14 mm/hr.
fClinical Correlation—Putting It All Together
What is the diagnosis?
Trigeminal neuralgia
The Science Behind the Diagnosis
Anatomy
The trigeminal nerve is the fifth cranial nerve, and it derives its name from its three branches: the ophthalmic (V1), the maxillary (V2), and the mandibular (V3) ( Fig. 13.3 ). The ophthalmic and maxillary nerves are comprised solely of sensory fibers, while the mandibular nerve has both sensory and motor fibers. The trigeminal nerve exits the pons as a single nerve root on each side of the pons. These bilateral nerve roots travel forward and laterally from the pons to form the gasserian ganglion (also known as the trigeminal ganglion), which is located in Meckel cave in the middle cranial fossa ( Fig. 13.4 ). The canoe-shaped gasserian ganglion is bathed in cerebrospinal fluid and is surrounded by dura mater.