✓ The technique of the dorsal selective rhizotomy as originally developed by Professor Fasano and by the author is described. The rhizotomy is performed through a one-level laminectomy at L-1. Exposure of the conus medullaris and the cauda equina at this level is adequate to thoroughly assess the reflex electrical response to stimulation of the lumbosacral roots and to section the selected roots/rootlets. This approach, based on over 100 surgical procedures, obviates the need for an extensive laminectomy in a growing child without compromising the clinical results.
Giancarlo Barolat-Romana and Sanford J. Larson
✓ Motor responses to standardized stimuli were evaluated in 18 comatose patients with abnormal motor reactions. Painful stimuli were applied to three areas: the supraorbital, sternal, and medial aspects of the arm. Stimulations were carried out with the upper limbs first flexed and then extended. The initial position of the arm significantly influenced the posturing pattern. With the arm initially flexed there was a significantly higher percentage of abnormal flexor reactions, and the opposite occurred with the arm initially extended. Supraorbital stimulation yielded a significantly higher number of extensor responses. Arm stimulation, instead, caused a higher percentage of abnormal flexor reactions. When painful stimulation was applied to an arm initially flexed, the percentage of extensor responses was extremely low. Conversely, supraorbital stimulation with the arms extended yielded the highest percentage of extensor responses.
The study shows that, within the frame of abnormal motor responses, the same patient can exhibit different reactions according to the site of stimulation and initial position of the upper extremities. These patterns are fairly constant and should be borne in mind in the evaluation of comatose patients.
Giancarlo Barolat, Dale Schaefer and Sergio Zeme
✓ A 21-year-old woman had recurrent progressive weakness/hypesthesia and pain in both lower extremities. At the age of 5 and 19 years, she had undergone surgical resection of a lipomyelomeningocele at L5—S1. Surgical exploration revealed that the cord was tethered and pulled over to the side by an excessively short right S-1 nerve root. The contralateral L-5 and S-1 nerve roots were markedly stretched. Division of the right S-1 nerve root resulted in prompt disappearance of pain in the lower extremities and improvement in neurological function.
Giancarlo Barolat, Fulvio Massaro, Jiping He, Sergio Zeme and Beth Ketcik
✓ A database is presented of sensory responses to electrical stimulation of the dorsal neural structures at various spine levels in 106 subjects subjected to epidural spinal cord stimulation. All patients were implanted for chronic pain management and were able to perceive stimulation in the area of pain. All patients entered in this study were able to reliably report their stimulation pattern. Several patients were implanted with more than one electrode array. The electrode arrays were placed in the dorsal epidural space at levels between C-1 and L-1. The structures that were likely involved include the dorsal roots, dorsal root entry zone, dorsal horn, and dorsal columns. At the present time, exact characterization of the structure being stimulated is possible only in limited instances. Various body areas are presented with the correspondent spine levels where implanted electrodes generate paresthesias. Areas that are relatively easy targets for stimulation are the median aspect of the hand, the abdominal wall, the anterior aspect of the thigh, and the foot. Some areas are particularly difficult to cover with stimulation-induced paresthesias; these include the C-2 distribution, the neck, the low back, and the perineum.
Giancarlo Barolat-Romana, Dennis Maiman, Paul Dernbach and Hongyung Choi
✓ The authors report a case of subdural metastasis from a prostatic carcinoma presenting as an acute intracranial subdural and intracerebral hemorrhage. The pertinent literature is reviewed.
Giancarlo Barolat-Romana, Joel B. Myklebust, David C. Hemmy, Barbara Myklebust and William Wenninger
✓ Six patients with intractable spasms after spinal cord injury underwent implantation of an epidural spinal cord stimulation system. All the patients experienced good relief postoperatively. In three patients spinal cord stimulation consistently produced immediate inhibition of the spasms. This was evident within less than 1 minute of stimulation. Conversely, the spasms reappeared within less than 1 minute after cessation of the stimulation. The clinical observations were confirmed by polygraphic electromyographic recordings.
Robert F. Traflet, Ashok R. Babaria, Giancarlo Barolat, H. T. Doan, Carlos Gonzalez and Mark M. Mishkin
✓ A case is presented in which a solitary chondroma arose from the clivus of a patient with Ollier's disease. These tumors are rare. The diagnostic value of computerized tomography and magnetic resonance imaging is discussed.