Ictal and interictal ECD-SPECT for focus localization in epilepsy.
Forty-one ECD (Technetium-99m-ethyl cysteinate dimer) SPECT investigations were undertaken in the course of a presurgical diagnostic work-up in 23 patients with pharmacoresistant focal epilepsy. In 21 patients, both an ictal and interictal SPECT were conducted. In the patients receiving ictal SPECT the tracer was injected between 7 and 30 s after the seizure onset. Of the interictal SPECTs 17 of 23 showed focal hypoperfusion which was consistent in 17 cases (74%) with the area of the electrophysiological focus (EF) and 6 patients had a normal interictal SPECT. Of the ictal SPECTs 18 of 21 (86%) showed regional hyperperfusion, 18 of them in the same location as the EF. Ictal SPECT showed a hypoperfusion similar to that in interictal SPECT in another 3 patients. In these cases seizure duration was short (28-54 s), so that the tracer reached the brain postictally. Our results show that ictal ECD-SPECT is an effective method for demonstrating an epileptogenic focus. Possible reasons for false-negative ictal SPECT results are discussed.
Runge
U
U
Department of Neurology, Ernst-Moritz-Arndt-University of Greifswald, Germany.
Kirsch
G
G
Petersen
B
B
Kallwellis
G
G
Gaab
M R
MR
Piek
J
J
Kessler
C
C
D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply / Q000000981:diagnostic imaging; D002648:Child; D003545:Cysteine / Q000031:analogs & derivatives*; D004569:Electroencephalography; D004827:Epilepsy / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D012039:Regional Blood Flow / Q000502:physiology; D012640:Seizures / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon
D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C059659:technetium Tc 99m bicisate; D003545:Cysteine