How is trigeminal neuralgia diagnosed?
Diagnosis is usually made by eliminating other problems that could cause similar pain in teeth, jaw, head, or sinuses. Because patients with the condition tend to avoid trigger points, avoiding chewing, shaving, touching or washing their faces can be a clue to diagnosis of trigeminal neuralgia. The conventional MRI scans used to rule out the presence of a brain tumor or multiple sclerosis as a cause of a patients face pain are not adequate to visualize the trigeminal nerve or an associated blood vessel. Fortunately, the continued improvement in MRI neuro-imaging now makes it possible to visualize both. The technique, which is called 3-D volume acquisition, is performed with contrast injection and utilizes thin cuts (0.8mm), without gaps similar to what was developed for MRI angiography and venography. The trigeminal nerve is easily visualized in the axial plane when the MRI series is centered at the midpoint of the fourth ventricle. To ensure an adequate evaluation, the nerve should be
