Trigeminal neuralgia (TN) can be classified by etiology as:
- classical TN, with neurovascular contact on magnetic resonance imaging (MRI)
- secondary TN due to underlying neurologic disease
- idiopathic TN1,2
Migraine is the most common underlying cause of trigeminal neuralgia
Many underlying diseases cause secondary trigeminal neuralgia, but how often is it caused by migraine? To find out, Octavio Carranza, Vasco de Quiroga University, Mexico, carried out a retrospective review of all cases of TN seen in his clinic between January 2014 and December 2019.
A total of 1604 patients presented with TN and after magnetic resonance imaging, 1205 were diagnosed with classical TN, 147 with idiopathic TN, and 252 with secondary TN.
The patients with secondary TN were found to have 28 different underlying diseases causing TN. Most of these diseases (19) were diagnosed in six or fewer patients, with nine of the diseases being diagnosed only one patient.
Migraine was the most common underlying disease, occurring in 36 (16%) patients.
Epidermoid cyst and postherpetic neuralgia were the second and third most common diagnoses occurring in 12% and 10% of patients, respectively.