Spinal cord infarction due to minor trauma

To the Editor: The use of cerebellar electrical stimulation as a means of improving physical function in cerebral palsy and other central nervous system alterations that affect muscle control has gained considerable attention in the past 2 years. Articles in medical journals and reports in the lay press imply that the improvement is significant for the majority of the people in whom the device was implanted. Review of the literature leads us to a different conclusion. This procedure has not produced as dramatic a change in patients as implied. Critical assessment of Dr. Cooper’s article’ indicates that only 38 percent of the treated patients had significant improvement in function. We met with members of Dr. Cooper’s staff and they indicated that while some people had significant change, the primary difference usually was a feeling of “being more relaxed. ” Actual improvement in function was only a matter of degree. For example, a person might have improved walking but if he was not already an ambulator, insertion of the stimulator did not allow him to become one. If this procedure were innocuous, the improvement noted possibly would be enough to warrant using the device in properly selected persons. However, definite problems exist. Gilman2 and his associates reported that animal studies using cerebellar stimulation for 205 hours revealed “ . considerable damage and loss of Purkinje cells in all specimens examined” and “ . the greatest changes occurring in tissues beneath the cathode and electrode. ” They have since confirmed this work, using stimulation of the same intensity and alternating the current exactly as is done in humans. In addition, there is a reduction in GABA levels in the brain at the site of the implant. Gilles3 stated that there was buildup of connective tissue around the implanted electrodes that “ . was at least half the thickness of the dura of the tentorium. ” It is our understanding that Dr. Cooper and his staff have elected to do no more cerebellar stimulation procedures because of difficulty with the electrical device. It is their intent to observe the 200 persons in whom they have already implanted the stimulator and then report the long-term effects. In view of the above, we believe that the potential dangers of this procedure are too great when weighed against the possible benefits. If, after only 3 years, the risk of adverse effects is this great, it is possible that more difficulty will arise. For these implanted devices to be successful, we should be able to offer long-term benefit with minimum or no adverse effect. We feel it is also important to note that this procedure is not accepted by most third-party carriers for insurance payment. It is also not allowed for payment by government agencies. Therefore, the cost of this procedure is borne by the family and it is our understanding that the charge for surgery alone is at least $1,500. The device costs an additional $3,500. This expense, plus the cost of hospitalization, is a heavy burden for most people. The purpose of the procedure is to improve function. Considering cost, risk of complications, and lack of even a 50 percent chance of success, the adverse effects seem to negate potential benefit. This is especially true when most of the improvement noted could be obtained by judicious use of more conventional and safer procedures, such as properly selected orthopedic surgery, bracing, therapy, and medication. We, therefore, urge that all persons involved in the care of patients with dysfunction of body movements secondary to brain alteration support a ban on insertion of additional cerebellar devices until the long-term results of the approximately 700 procedures already done nationally can be properly assessed.