Medicine: Attack on Pain

“The relief of pain is obviously one of the main functions of physicians,” Boston Psychiatrist Frank Ervin noted last week, then added: “Ironically, it’s one of the things we do least well—partly because we don’t understand it.” But Dr. Ervin is one of a Massachusetts General Hospital research team that is using ultramodern brain surgery both to subdue the severest forms of pain and to learn more about pain’s mechanisms.

Several diseases, of which cancer is the commonest, sometimes produce pain so continuous and intense that the most potent narcotics will not relieve it. One approach has been to cut white nerve bundles in the front part of the brain (lobotomy or leucotomy). This makes many victims better able to tolerate their pain, even though its actual intensity may not be reduced. Greatest danger: an overall dulling of the personality. More radical but also more logical is an attack through the thalamus, part of the central nervous system which relays many pain impulses to the higher perception centers. Biggest drawback: the thalamus, tucked away in the middle of the skull, is hard to get at, and early operations on it often missed the target by a fraction of an inch.

Elaborate Technique. At Massachusetts General, Neurosurgeon Vernon H. Mark worked with Psychiatrists Ervin and Thomas P. Hackett to make the operation more precise and predictable. First came refinements of the stereotactic apparatus which plots a point inside the patient’s skull in three dimensions. Then an elaborate technique was developed. In stage one, the surgeon drills a small, carefully plotted hole in each side of the skull to permit injection of dye for making detailed brain X rays. After two or three days comes stage two: another hole is drilled higher up in the skull, and the surgeons insert an insulated steel wire through three inches of brain until its thickened electrode tip lodges in the thalamus. The outer end is anchored to the skull.

Some patients have felt short-lived pain relief merely from implantation of the electrode. But all eventually need stage three: a week after implantation, the doctors send a gentle electric current through the electrode to find out whether the patient feels a tingling in his fingers, arm or foot (always on the side opposite the electrode). This gives yet another check on placement. Finally they use a strong enough current, under anesthesia, to destroy a small part of the thalamus.

Surprising Fact. So far, all but two of the patients treated have lost most of their pain. The exceptions: one with lung cancer, one with “phantom limb” pain after an arm amputation. Best results have been in cancers of the face and neck. The surgeons leave the electrodes in place so that the patients can go home and lead drug-free, lives, as near normal as their disease will permit. They can return for treatment to destroy a further part of the thalamus if pain recurs.

Besides many technical details about the thalamus, the Boston researchers have learned a surprising, basic fact: thalamotomy (as the operation is called) works exactly opposite to lobotomy—it relieves the pain itself, but not the reactions of anxiety, suffering and fear of death.