Radiology for Trigeminal Neuralgia

Abstract

The diagnosis of trigeminal neuralgia (TGN) is mainly based on patient’s history and clinical examination. Classically, the patient presents with characteristic paroxysm of pain, with short and severe episodes, which is typically unilateral, and along the course of the trigeminal nerve. There is a greater predilection towards the right side. Apart from the idiopathic variety, secondary causes of TGN must be ruled out, as neuropathy of trigeminal nerve may involve the nerve anywhere along its course, from the nerve nuclei to the peripheral branches. Since clinical findings alone are not sufficient to localize the site of the causative lesion, magnetic resonance imaging (MRI) must be carried out before any intervention is planned. Imaging may also help to diagnose an enlarged loop of artery or vein compressing the trigeminal nerve, i.e. neurovascular compression (NVC) at the cerebellopontine (CP) angle, plaques in multiple sclerosis (MS), and tumor in the CP angle region. A thorough understanding of the x-ray anatomy of base and lateral view of the skull is important, as majority of the interventions are performed with fluoroscopic-guided techniques. This chapter covers the diagnostic and therapeutic aspects of radiology in patients of TGN.