A brainstem "mini-discharge" syndrome (anesthesia dolorosa).

Chronic pain consisting of anesthesia dolorosa secondary to bilateral interruption of the trigeminal nerves is presented as a brain stem reticular denervation syndrome. Electrothalamograms revealed fast frequency discharges in the mesothalamic prerubral and centermedian reticular formation. Mesothalamic electrical stimulation attenuated the discharges. Pain and other symptoms presumably of brainstem origin also were attenuated or abolished by therapeutic electrical stimulation twice daily. It is postulated that brain stem-represented behavioral generators are implicated by the reticular discharges in order to produce the complex symptomatology. Consequently the symptom complex is collectively identified as a brainstem "mini-discharge" syndrome. A theoretical discussion is presented to defend the thesis that reticular denervation-induced low threshold discharge system accounts for the episodic states of pain, dyskinesia, mood, and memory disturbances.