Table 3.
Concordance between ALFF clusters and SEEG-defined SOZ sub-classified by clinical characteristics.
| ALFF |
χ 2 | p valuea | |||
|---|---|---|---|---|---|
| Concordant no. (%) | Discordant no. (%) | Negative no. (%) | |||
|
| |||||
| Brain MRI b | 1.29 | 0.78 | |||
| Non-lesional (n=9) | 6 (66.7) | 2 (22.2) | 1 (11.1) | ||
| Lesional (n=10) | 8 (80.0) | 2 (20.0) | None | ||
| Interictal scalp EEG | 2.41 | 0.36 | |||
| With IEDs (n=12) | 10 (83.3) | 2 (16.7) | None | ||
| Without IEDs (n=7) | 4 (57.1) | 2 (28.6) | 1 (14.3) | ||
| Epileptic syndrome | 1.83 | 0.58 | |||
| TLE (n=9) | 7 (77.8) | 1 (11.1) | 1 (11.1) | ||
| ETLE (n=10) | 7 (70.0) | 3 (30.0) | None | ||
| SOZ distribution | 4.98 | 0.07 | |||
| Deep-seated area (n=16) | 13 (81.3) | 3 (18.7) | None | ||
| Convexity of brain (n=3) | 1 (33.3) | 1 (33.3) | 1 (33.3) | ||
| Pathology (n=11) c | 8.99 | 0.36 | |||
| FCD I (n=7 d) | 6 (85.7) | None | 1 (14.3) | ||
| FCD IIA (n=2) | 2 (100.0) | None | None | ||
| FCD IIB (n=1) | None | 1(100.0) | None | ||
| Heterotopia (n=1) | 1(100.0) | None | None | ||
| Surgical outcome e (n=8) | 1.21 | 1.00 | |||
| Seizure-free (n=6) | 4 (66.7) | 1 (16.7) | 1 (16.7) | ||
| Non-seizure-free (n=2) | 2 (100.0) | None | None | ||
Statistical threshold was set at P< 0.05, two tailed.
MRI findings were defined by official radiological report.
FCD lesions were classified based on the ILAE 2016 recommendation of neuropathologic workup of epilepsy surgery brain tissue and the ILAE 2011 FCD classification guidelines.
Two patients with double pathology (P12 and P19 in Table 1), whose concordant ALFF clusters were located in the dysplastic tissue, were included under the FCD category.
Surgical outcome was defined by the ILAE classification and dichotomized as seizure-free (only including ILEA-1) or non-seizure-fee in patients with > 1 year postoperative follow-up.
ALFF= amplitude of low frequency fluctuations; SEEG= Stereoelectroencephalography; SOZ= seizure onset zone; no.= number; MRI= magnetic resonance image; EEG= electroencephalography; IEDs = interictal epileptiform discharges; TLE= temporal lobe epilepsy; ETLE= extratemporal lobe epilepsy; FCD= Focal cortical dysplasia