CT changes after lumbar percutaneous automated nucleotomy.

In order to assess changes occurring in disk hernias and disk spaces following percutaneous nucleotomy a follow-up CT was carried out an average of 6 months after treatment of 69 disks in 60 patients. Forty-three of the disks were also reexamined at an average of 11 months after the first follow-up. Twenty-seven percent of the hernias were reduced in size at the first follow-up. Fourteen percent were reduced and 7% had increased between the first and second follow-ups. The medium-sized and large hernias were more frequently reduced compared to the smaller ones. Reduction of the disk space was found in 29% of the cases at first follow-up. An additional 24% were reduced between the first and second follow-ups. No association was demonstrated between change in size of the herniation or disk space and clinical outcome or amount of nucleus material removed at nucleotomy.