|
|
|||||||||
Division of Nuclear Medicine, Department of Radiology, and Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia; and Departments of Neurosurgery and Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania
FDG PET is often used to help localize the seizure focus before surgery in patients with medically refractory temporal lobe epilepsy. However, the ability of certain patterns of metabolic landscape to predict postsurgical seizure outcome has not been well characterized. The purpose of this retrospective study was to determine whether FDG PET abnormalities elsewhere in the brain, in combination with those in the temporal lobes, can be used to predict seizure outcome after surgery. Methods: Eighty patients with refractory temporal lobe seizures were imaged with PET after intravenous administration of 115 µCi/kg FDG. Images were interpreted without knowledge of clinical information by an experienced reviewer to determine seizure focus and regional metabolic changes in the brain. Metabolic activity scores were assigned for cortical and subcortical structures using the following criteria: 4 = normal activity, 3 = mildly decreased activity, 2 = moderately decreased activity, 1 = severely decreased activity, and 0 = no activity. A laterality index for each region was calculated using the equation 100 x [right left]/[1/2 x (right + left)]. Seizure focus localization was based on the laterality of temporal lobe metabolic activity and was compared with that determined by scalp and depth electrodes and MRI results. Comparisons were made between asymmetries in metabolic activity in various brain structures and postoperative seizure frequency. Postoperative outcome was determined on the basis of cessation (complete disappearance of seizures) or continuation of seizure activity, regardless of frequency, compared with the preoperative state. Results: All 64 patients who were free of seizures postoperatively had either no thalamic asymmetry or reduced metabolism on the side from which the temporal lobe was removed. In contrast, 5 of 16 patients (31%) with postoperative seizures of any frequency had hypometabolism in the thalamus contralateral to that of the removed temporal lobe. All 5 patients with reverse thalamic asymmetry had postoperative seizures. Patients with thalamic hypometabolism ipsilateral to the removed temporal lobe also had an increased risk of postoperative seizures, but this risk was not as high as in patients with the contralateral abnormality. In these patients, the temporal lobe (which appeared hypometabolic on PET) was determined to be the site of the seizure on the basis of information besides that provided by PET before surgery. Conclusion: This study indicated that, in patients with temporal lobe epilepsy, thalamic metabolic asymmetry, particularly in the reverse direction to that of the temporal lobe asymmetry, was associated with a poor postsurgical outcome compared with no or matched asymmetry. This determination may be important in evaluating patients for, and selecting optimal candidates for, surgical intervention.
Key Words: PET seizure thalamus outcome
Received Dec. 13, 1999; revision accepted Jun. 30, 2000.
For correspondence or reprints contact: Andrew B. Newberg, MD, Division of Nuclear Medicine, 110 Donner Bldg., H.U.P., 3400 Spruce St., Philadelphia, PA 19104.
This article has been cited by other articles:
![]() |
T. J. O'Brien, K. Miles, R. Ware, M. J. Cook, D. S. Binns, and R. J. Hicks The Cost-Effective Use of 18F-FDG PET in the Presurgical Evaluation of Medically Refractory Focal Epilepsy J. Nucl. Med., June 1, 2008; 49(6): 931 - 937. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. P. Hetherington, R. I. Kuzniecky, K. Vives, O. Devinsky, S. Pacia, D. Luciano, B. Vasquez, S. Haut, D. D. Spencer, and J. W. Pan A subcortical network of dysfunction in TLE measured by magnetic resonance spectroscopy Neurology, December 11, 2007; 69(24): 2256 - 2265. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. B. Vinton, R. Carne, R. J. Hicks, P. M. Desmond, C. Kilpatrick, A. H. Kaye, and T. J. O'Brien The extent of resection of FDG-PET hypometabolism relates to outcome of temporal lobectomy Brain, February 1, 2007; 130(2): 548 - 560. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Guye, J. Regis, M. Tamura, F. Wendling, A. M. Gonigal, P. Chauvel, and F. Bartolomei The role of corticothalamic coupling in human temporal lobe epilepsy Brain, July 1, 2006; 129(7): 1917 - 1928. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Benedek, C. Juhasz, D. C. Chugani, O. Muzik, and H. T. Chugani Longitudinal Changes in Cortical Glucose Hypometabolism in Children With Intractable Epilepsy J Child Neurol, January 1, 2006; 21(1): 26 - 31. [Abstract] [PDF] |
||||
![]() |
E. Y. Joo, S. B. Hong, H. J. Han, W. S. Tae, J. H. Kim, S. J. Han, D. W. Seo, K.-H. Lee, S.-C. Hong, M. Lee, et al. Postoperative alteration of cerebral glucose metabolism in mesial temporal lobe epilepsy Brain, August 1, 2005; 128(8): 1802 - 1810. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Blumenfeld and J. Taylor Why do Seizures Cause Loss of Consciousness? Neuroscientist, October 1, 2003; 9(5): 301 - 310. [Abstract] [PDF] |
||||
![]() |
J. Sojkova, P. J. Lewis, A. H. Siegel, A. M. Siegel, D. W. Roberts, V. M. Thadani, and P. D. Williamson Does Asymmetric Basal Ganglia or Thalamic Activation Aid in Seizure Foci Lateralization on Ictal SPECT Studies? J. Nucl. Med., September 1, 2003; 44(9): 1379 - 1386. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | RSS | TABLE OF CONTENTS |
| JOURNAL OF NUCLEAR MEDICINE TECHNOLOGY | THE JOURNAL OF NUCLEAR MEDICINE |