Postherpetic Neuralgia

Postherpetic neuralgia (PHN) after acute herpes zoster ophthalmicus involves unilateral pain persisting or recurring for at least 3 months in the distribution of one or more branches of the trigeminal nerve. Patients often describe the pain associated with PHN as a deep aching or burning, dysesthetic, hyperesthetic, or electric shock-like sensation. The incidence of PHN increases with age and varies from 7 to 27%, depending on age group. 1 A subset of these patients develops medication-refractory PHN and should be referred for neurosurgical evaluation. Motor cortex stimulation (MCS) and trigeminal nucleus caudalis dorsal root entry zone (NC DREZ) lesioning are two therapies that may provide substantial relief to patients suffering from medication-refractory, postherpetic neuropathic facial pain.