[Relief of intractable post-herpetic neuralgia with gasserian ganglion block using methyl prednisolone acetate and with TENS].

A 58 year old man had been suffering from intractable left ophthalmic post herpetic neuralgia (PHN) for 7 years. He has also been treated for polyarteritis nodosa for 10 years. For pain relief, he was treated initially with frequent (4 times a day) stellate ganglion block (SGB) and peripheral ophthalmic nerve block for a month without relief. Then supraorbital nerve block with neurolytics, TENS and acupuncture were done with a slight relief of his pain. Recently his pain became worse even with imipramine 75 mg and carbamazepine 100 mg a day which relieved effectively the patient from the pain for the last 3 years. The pain was so severe to disturb his usual daily activity. Gasserian ganglion block with methyl prednisolone acetate 10 mg was done. After the block, his ADL improved markedly. Three months after the block, he had no spontaneous pain and slight pain with light touch on the injured skin did not annoy him. Several days before the block, electric stimulation to control his pain was tested. Stimulation with the electricity (4.5 mA, 10 cycle and 400 microseconds) brought him complete relief from the pain during the stimulation. Trigeminal SEP showed no response to the stimulation of injured skin.