Postcentral Topectomy for Pain Relief: A Historical Review and Possible Improvements

Abstract

Postcentral topectomy is a neurosurgical procedure, practiced in the mid-20th century, in which surgical ablations of the primary somatosensory cortex were used as a therapeutic means of treating patients suffering from intractable chronic pain. While successful in curing some—but not all—patients, the procedure was poorly understood and eventually became displaced by methods that more consistently stopped patient complaints of pain, such as opiates and frontal lobotomies. However, a more recent discovery of a nociresponsive region in the transitional zone between the primary somatosensory cortex and the primary motor cortex (lying in Brodmann Area 3a anterior to its better known proprioceptive region) raises the possibility that the outcome of postcentral topectomy depended in each patient on whether the ablation extended deep enough into the central sulcus to remove this cortical region. Here we review every postcentral topectomy case we could find in the neurosurgical literature in order to evaluate its past effectiveness and to reassess its potential in light of modern knowledge of the cerebral cortex. We found 17 full-text reports from 16 different surgical teams describing outcomes of the procedure in 27 patients. Among those, in only 5 patients the procedure either failed to abolish the targeted chronic pain or the pain returned to its preoperational levels several weeks or months after the surgery. In the other 22 patients, their pain stayed abolished or at least significantly reduced as of the last evaluation by the treating physician (which was one year or more for 9 patients). We propose that the probability of a successful outcome might be brought to near 100% by selective targeting—guided by functional imaging—of the nociresponsive region in Area 3a.