REGIONAL CEREBRAL BLOOD FLOW PATTERNS IN UNILATERAL MESIAL TEMPORAL LOBE EPILEPSY: STATISTICAL PARAMETRIC MAPPING OF ICTAL AND INTERICTAL SPECT
Abstract number :
1.235
Submission category :
Year :
2003
Submission ID :
3651
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Seung Bong Hong, Woo Suk Tae, Eun Yeon Joo, Dae Won Seo, Seung Chyul Hong, Moon Hyang Lee, Jee-Hyun Kim Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Neurosurgery, Samsung Medical Center, Sungkyun
To investigate the regional cerebral blood flow of patients with mesial temporal lobe epilepsy (mTLE), we performed the statistical parametric mapping (SPM) analysis with ictal SPECTs of patients and interictal SPECTs of the patients and normal subjects.
Nineteen normal subjects and 38 patients with mTLE (22 left, 16 right) were included. All underwent brain SPECT. For SPM analysis, all SPECT images were spatially normalized with linear 12 parameters affine transformation and then smoothed with 14-mm FWHM (full width at half maximum). The left (mean age: 30.0[plusmn]8.75 years, 7 men, 13 women), and right (mean age: 28.4[plusmn]10.30, 8 men, 8 women) mTLE groups were statistically compared with the normal subjects (mean age: 34.1[plusmn]9.88, 9 men, 10 women) by SPM t-test, and paired t-test was performed between ictal and interictal SPECTs of the patients. The positive and negative contrasts were used to display the regions of hypo- or hyper-perfusion, respectively. The significance level was set to false discovery rate corrected [italic]p[/italic] [lt] 0.05, and spatial extent was set to k [gt] 50.
In interictal state, the ipsilateral hippocampus, both thalami, pericentral gyri, left insula, and both medial frontal lobes showed hypoperfusion, whereas both posterior lateral temporal areas showed hyperperfusion. In ictal state, the rCBF of ipsilateral temporal lobe to the epileptic focus and both prefrontal white matters increased, while both medial frontal lobe showed hypoperfusion. In the right mTLE, the left hippocampus and insula showed hypoperfusion during interictal state. In paired t-test, ipsilateal temporal lobe, hippocampus, thalamus, putamen, insula, and both precentral gyri showed hyperperfusion.
Surprisingly, the hypoperfusion and hyperperfusion patterns of patients with mTLE were similar between interictal and ictal states. These findings indicate that occurrence and propagation of epileptic discharges happen in not only ictal state but also interictal period. The hypoperfusion patterns suggest that the cortico-thalamo-hippocampal-insula circuit was impaired during interictal state while temporal and prefrontal regions showed hypofunction during ictal period.