Contribution of SISCOM Imaging in the Presurgical Evaluation of Temporal Lobe Epilepsy Related to Dysembryoplastic Neuroepithelial Tumors
Article first published online: 20 MAR 2002
Volume 43, Issue 3, pages 270–276, March 2002
How to Cite
Valenti, M. P., Froelich, S., Armspach, J. P., Chenard, M. P., Dietemann, J. L., Kerhli, P., Marescaux, C., Hirsch, E. and Namer, I. J. (2002), Contribution of SISCOM Imaging in the Presurgical Evaluation of Temporal Lobe Epilepsy Related to Dysembryoplastic Neuroepithelial Tumors. Epilepsia, 43: 270–276. doi: 10.1046/j.1528-1157.2002.25101.x
- Issue published online: 20 MAR 2002
- Article first published online: 20 MAR 2002
- Revision accepted December 11, 2001.
- Temporal lobe epilepsy;
- Dysembryoplastic neuroepithelial tumors;
- Cerebral tumors;
- Magnetic resonance imaging;
- Single-photon emission computed tomography
Summary: Purpose: Dysembryoplastic neuroepithelial tumors (DNTs) are a group of glioneuronal supratentorial and intracortical lesions often associated with the early onset of intractable and crippling partial seizures. They are characterized by their location, multinodular architecture, and heterogeneous cell composition, with a specific glioneuronal element in the specific form. Foci of cortical dysplasia may be associated with the tumoral lesion, and identifying the presence and the extent of cortical dysplasia is not always easy on magnetic resonance images (MRIs). The purpose of this article is to evaluate, retrospectively, the usefulness of ictal single-photon emission computed tomography (SPECT) imaging to assess the presence and the extent of cortical dysplasia associated with DNTs in nine patients with intractable temporal lobe epilepsy related to histopathologically confirmed DNTs.
Methods: The results of the subtraction of ictal and interictal SPECT coregistered to MRI (SISCOM) were compared with the results of the examinations of pathological material after surgery.
Results: SISCOM showed a strongly hyperperfused area corresponding anatomically to electroclinical abnormalities and to the location of DNTs on MRI. A circumscribed hyperperfusion was present in DNTs without cortical dysplasia, limited to the location of the tumor on MRI. In cases of associated cortical dysplasia, a widespread hyperperfusion including areas corresponding to normal perilesional regions on MRI was found.
Conclusions: SISCOM, used among presurgical investigations, contributes to detecting cortical dysplasia associated with DNTs. Concordance between the symptomatogenic zone (defined from the medical history and electroclinical data), MRI scans, SISCOM pattern, and complete resection of the epileptic zone was predictive of a good postsurgical outcome.