Trigeminal Neuralgia: A Condition to Be Better Understood

I read the paper entitled “Trigeminal Neuralgia: Frequency of Occurrence in Different Nerve Branches”, published in your journal (1). The data presented confirms the findings of previous papers (2-4), as was also mentioned by the author. Such findings help the clinicians to diagnose the disease. However, some other points need to be mentioned; even though this study reports no case of bilateral trigeminal neuralgia, previous publications reported that it may affect 1-5% of the patients (5, 6), and another author mentioned that bilateral cases should suggest a systemic involvement, such as multiple sclerosis (MS) or cranial tumor (7). We can conclude that bilateral cases are rare, but not impossible; and a clinician should be suspicious of a systemic condition when examining a patient with bilateral trigeminal neuralgia (TN). Considering that TN is a clinical diagnosis, the clinician should not only rely on the epidemiologic data,even though it might help on the differential diagnosis.