Microsurgical DREZ-lesion in the treatment of deafferentation pain

The lesion of the dorsal root entry zone (DREZL) of the spinal cord, recently introduced by Nashold and performed with radiofrequency or with laser, may be carried out with a microsurgical technique. Since 1978 up 1982 we have treated a series of 12 patients suffering from Pancoast's syndrome with a C8-T2 selective posterior rhizotomy (SPR). It has been observed that every deafferentative aspect of the pain was completely relieved. Such effect on the deafferentative aspect of the pain was most probably due to a lesion on the perforating vessels feeding the posterior grey horn. The lesion of this structure was therefore ischemic and this operation had to be indicate for the treatment of such pain. A series of 8 patients, suffering from cancer pain projected to anaesthetic areas, and 2 patients with benign post-thoracotomy pain, underwent to microsurgical DREZ lesion. The relief from pain was complete and no complications concerning pyramidal or posterior pathways involvement was observed. Preliminary good results suggest that a more selective lesion is possible with the microsurgical DREZ. It should be interesting a comparison between more large series of microsurgical DREZL and the more tested radiofrequency lesion.